1,990 results
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2. The Evolutionary Path and Emerging Trends of Circulating Fluidized Bed Technology: An Integrated Analysis through Bibliometric Assessment and Data Visualization.
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Chen, Qimei, Gou, Yurong, Wang, Tangrong, Liu, Pengbo, and Zhu, Jianguo
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GLOBAL environmental change ,MATERIALS science ,ENVIRONMENTAL degradation ,DATA visualization ,BIBLIOMETRICS - Abstract
Confronted with the significant challenges of global climate change and environmental deterioration, the pursuit of carbon emission peaks and the realization of carbon neutrality have become a collective goal for countries worldwide. As an exemplary combustion technology noted for its efficiency and environmental friendliness, the circulating fluidized bed (CFB) is instrumental in curbing the release of carbon dioxide alongside other deleterious gases. The technology is pivotal in promoting the clean and efficient use of coal, simultaneously expediting the global shift towards a sustainable, green, and low-carbon future. This study employs a bibliometric analysis, a social network analysis, and information visualization techniques to delve into the evolution of CFB technology, leveraging the Web of Science database (SCI-EXPANDED and CPCI-S) and the Derwent Innovations Index (DII). Through a meticulous examination of academic papers and patent literature related to CFB technology, this research unveils the developmental trajectory and trends of CFB technology, providing a scientific foundation and reference for strategic technology planning and focused research in key areas. The findings indicate that, while there is a downward trend in the global publication of academic papers on CFB technology, the number of patent applications continues to grow steadily. CFB technology has achieved significant advancements in enhancing combustion efficiency, environmental protection, energy utilization, and waste management, and is progressing towards a direction of diversification and greater efficiency. Moving forward, the development of CFB technology should concentrate on pivotal areas such as material science, fluid dynamics simulation, environmental impact assessment, system integration, and intelligentization, to foster ongoing innovation and a broad application of the technology. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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3. The role of frames in shaping the representation of local knowledge and concerns in scientific texts.
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Roos, Roxana
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GLOBAL environmental change ,CLIMATE change ,INDIGENOUS peoples ,ENVIRONMENTAL management ,AWARENESS - Abstract
Research teams working with indigenous people or local communities in the field of global environmental change represent local knowledge and concerns related to climate or environmental issues in the resulting scientific texts. However, by highlighting some aspects in particular ways and fading others to the background, every representation simultaneously reveals, conceals, and distorts aspects of what is represented. This paper aims to analytically highlight how frames in scientific texts are at work in emphasizing some aspects of local knowledge and concerns while fading other aspects into the background, which inevitably has micro and macro consequences through how local knowledge is incorporated, represented, and added to the body of knowledge of a given field. I have adapted a widely used frame concept from media studies to make it suitable for the analysis of scientific texts. The proposed method identifies main frames of a paper, maps how devices for achieving selective emphases, such as repetitive formulations and strong words, are at work in the text, and elicits how the frame's key functions occur in papers: (1) identify problems, (2) diagnose causes, (3) make moral judgments, (4) suggest solutions or offer a path toward solutions, and (5) attribute roles. Points (4) and (5) are specifically designed for the analysis of scientific texts. In addition, I have added a step that shows how frames shape representations of local knowledge and concerns in scientific texts. This method is meant to develop reflexive awareness among the scholarly community about their writing practices and promote critical thinking about the unintended impacts that uncritical reproduction of taken-for-granted frames may have through their shaping of representations of local and indigenous knowledge and concerns. To illustrate the potential of the frame concept for analyzing scientific texts, I applied the new method to two papers. Further, the paper discusses the potential of frame analysis as a tool for reflexivity among research teams that work with and within local communities. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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4. Introducing the Anthropocene: The human epoch: This article belongs to Ambio's 50th Anniversary Collection. Theme: Anthropocene.
- Author
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Steffen, Will
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EARTH system science ,SOLAR radiation management ,CARBON cycle ,GEOLOGICAL time scales ,ANTHROPOCENE Epoch ,GLOBAL environmental change ,BIOSPHERE - Abstract
One was the Planetary Boundaries framework, introduced by Johan Rockström and colleagues in 2009, which aims to provide a natural-science based framework for describing a Holocene-like state of the Earth System and the intrinsic boundaries of the Earth System that should not be transgressed if such a stable state is to be maintained (Rockström et al. [10]). Introducing the Anthropocene: The human epoch: This article belongs to Ambio's 50th Anniversary Collection. The other is the polycentric governance systems approach introduced by the late Elinor Ostrom ([9]), which, in the context of the S et al. paper, was proposed as a more appropriate governance system for the Anthropocene than the present governance systems that are driving us deeper towards a planetary crisis. The SCM paper foreshadowed the debate on the start date for the Anthropocene, which became prominent from 2009 with the formation then of the Anthropocene Working Group to explore the Anthropocene as a potential new interval in the Geologic Time Scale (AWG [1]). [Extracted from the article]
- Published
- 2021
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5. Effect of environmental changes on vegetable and legume yields and nutritional quality.
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Scheelbeek, Pauline F. D., Bird, Frances A., Tuomisto, Hanna L., Green, Rosemary, Harris, Francesca B., Joy, Edward J. M., Chalabi, Zaid, Allen, Elizabeth, Haines, Andy, and Dangour, Alan D.
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GLOBAL environmental change ,FOOD security ,LEGUME yields ,VEGETABLE yields ,AGRICULTURAL productivity - Abstract
Environmental changes threaten agricultural production, food security, and health. Previous reviews suggest that environmental changes will substantially affect future yields of starchy dietary staples. To date, no comprehensive global analysis of the impacts of environmental change on (nonstaple) vegetables and legumes--important constituents of healthy diets--has been reported. We systematically searched for articles published between 1975 and 2016 on the effects of ambient temperature, tropospheric carbon dioxide (CO
2 ), and ozone (O3 ) concentrations, water availability, and salinization on yields and nutritional quality of vegetables and legumes. We estimated mean effects of standardized environmental changes using observed exposure-response relationships and conducted meta-analyses where possible. We identified 174 relevant papers reporting 1,540 experiments. The mean (95% CI) reported yield changes for all vegetables and legumes combined were +22.0% (+11.6% to +32.5%) for a 250-ppm increase in CO2 concentration, -8.9% (-15.6% to -2.2%) for a 25% increase in O3 concentration,-34.7% (-44.6% to -24.9%) for a 50% reduction in water availability, and -2.3% (-3.7% to -0.9%) for a 25% increase in salinity. In papers with baseline temperatures >20 °C, a 4 °C increase in temperature reduced mean yields by -31.5% (-41.4% to -21.5%). Impacts of environmental changes on nutritional quality were mixed. In a business-as-usual scenario, predicted changes in environmental exposures would lead to reductions in yields of nonstaple vegetables and legumes. Where adaptation possibilities are limited, this may substantially change their global availability, affordability, and consumption in the mid to long term. Our results stress the importance of prioritizing agricultural developments, to minimize potential reductions in vegetable and legume yields and associated negative health effects. [ABSTRACT FROM AUTHOR]- Published
- 2018
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6. Research into mechanical modeling based on characteristics of the fracture mechanics of ice cutting for scientific drilling in polar regions.
- Author
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Lv, Xinyu, Cui, Zhihao, Wang, Ting, Wen, Yumin, Liu, An, and Wang, Rusheng
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GLOBAL environmental change ,CUTTING force ,ICE cores ,CORE drilling ,ICE mechanics - Abstract
Scientific drilling in polar regions plays a crucial role in obtaining ice cores and using them to understand climate change and to study the dynamics of polar ice sheets and their impact on global environmental changes (sea level, ocean current cycle, atmospheric circulation, etc.). Mechanical rotary cutting is a widely used drilling method that drives the cutter to rotate to cut and drill through ice layers. It is necessary to conduct in-depth research on the brittle fracture behavior of ice and mechanical model and to analyze the factors and specific mechanisms (cutter's angle, rotation speed of the drill bit, and cutting depth) affecting cutting force for the rational design of ice core drill systems, improving the efficiency of ice core drilling and ensuring the drilling process runs smoothly. Therefore, in this paper, the process of ice cutting was observed, the fracture mechanics characteristics of the ice cutting process were analyzed, the formation process of ice chips was divided into three stages, and a mathematical model for the cutting force was established based on the observation results. The paper describes the damage conditions of ice failure and points out the factors and specific laws influencing cutting force. Furthermore, the cutting force generated under various experimental conditions was tested. Based on specified real-time variation curves of cutting force, the characteristics of cutting force were analyzed during the cutting and drilling process. Based on comparison to results of the average cutting force, the influence mechanism of various parameters acting on the cutting force was obtained. This proves the correctness of the mathematical model of the cutting force and provides a theoretical reference for the calculation of the cutting force during ice cutting and drilling in polar regions. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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7. Ecological and Environmental Effects of Land Use and Cover Changes on the Qinghai-Tibetan Plateau: A Bibliometric Review.
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Liang, Ying and Song, Wei
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BIBLIOMETRICS ,LAND cover ,GLOBAL environmental change ,LAND use ,LAND management ,ENVIRONMENTAL security - Abstract
The Qinghai-Tibetan Plateau (QTP), known as the "Third Pole of the Earth", contains fragile ecosystems and is sensitive to global environmental changes. With the intensification of climate change and human activities, the land cover of the QTP is changing significantly, which affects its function as an ecological security barrier. This paper searched 379 papers in the Web of Science core database, conducted a bibliometric analysis, and proposed potential future research directions to gain a macroscopic understanding of the impact of land use and cover change (LUCC) on the regional and global ecological environment of the QTP. The results are as follows. (1) The period from 1995 to 2022 witnessed an overall increase in the number of publications in this field with a high development potential. (2) Climate change, land use, China, impacts, conservation, and management were high-frequency keywords in the field; among these, climate change has received increasing research attention since 2018. (3) The field included three main research directions: the impact of LUCC on biodiversity, the impact of land degradation on ecosystems, and the impact of climate change and land use changes on ecosystem services. (4) The development and evolution of research hotspots were mainly focused on three aspects: the impact of cultivated land expansion and deforestation, the impact of land use management and conservation, and the impact of climate change and human activities on LUCC. (5) Future research should focus on improving the accuracy of land use and cover data on the QTP, assessing and preventing the ecological risks of LUCC, investigating the impacts of human activities on LUCC and the ecological environment, and exploring the interactions between climate change and human activities on the ecological environment. The findings of this paper will help researchers and stakeholders gain a rapid and comprehensive understanding of this research area and thus contribute to the sustainable development of the QTP. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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8. Technical Framework and Preliminary Practices of Global Geographic Information Resource Construction.
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Zhang, Hongwei, Chen, Jiage, Wu, Chenchen, and Chen, Lijun
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INFORMATION resources ,GLOBAL environmental change ,DIGITAL elevation models ,VECTOR data ,TECHNICAL specifications - Abstract
High-precision and real-time global geographic information data are fundamental and strategic resources in various fields such as safeguarding global strategic interests, studying global environmental changes, and planning for sustainable development. However, due to challenges related to ground control and obtaining reference information, the development of global geographic information resources faces significant hurdles in terms of geometric positioning, information extraction, and data mining. This paper starts with the characteristics of domestically produced remote sensing images and proposes a comprehensive technical framework centered around "uncontrolled geometric positioning, intelligent interpretation of typical elements, mining of multi-source data from abroad, and intelligent hybrid collection and compilation of Digital Elevation Models (DEMs)." The paper elaborates on the key technical challenges that need to be overcome and their corresponding solutions. It also outlines the development of relevant data products and production technical specifications. Multiple production-oriented software tools were developed, leading to the creation of a variety of data products in multiple types and scales, including global 30-meter land cover data, DEM data, core vector data, and more. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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9. Co-variation of metabolic rates and cell-size in coccolithophores.
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Aloisi, G.
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COCCOLITHOPHORES ,GLOBAL environmental change ,PHYTOPLANKTON ,PHOTOSYNTHESIS ,CELL size - Abstract
Coccolithophores are sensitive recorders of environmental change. The size of their coccosphere varies in the ocean along gradients of environmental conditions and provides a key for understanding the fate of this important phytoplankton group in the future ocean. But interpreting field changes in coccosphere size in terms of laboratory observations is hard, mainly because the marine signal reflects the response of multiple morphotypes to changes in a combination of environmental variables. In this paper I examine the large corpus of published laboratory experiments with coccolithophores looking for relations between environmental conditions, metabolic rates and cell size (a proxy for coccosphere size). I show that growth, photosynthesis, and to a lesser extent calcification, co-vary with cell size when pCO
2 , irradiance, temperature, nitrate, phosphate and iron conditions change. With the exception of phosphate and temperature, a change from limiting to non-limiting conditions always results in an increase in cell size. An increase in phosphate or temperature produces the opposite effect. The magnitude of the coccosphere size changes observed in the laboratory is comparable to that observed in the ocean. If the biological reasons behind the environment-metabolism-size link are understood, it will be possible to use coccosphere size changes in the modern ocean and in marine sediments to investigate the fate of coccolithophores in the future ocean. This reasoning can be extended to the size of coccoliths if, as recent experiments are starting to show, coccolith size reacts to environmental change proportionally to coccosphere size. I introduce a simple model that simulates the growth rate and the size of cells forced by nitrate and phosphate concentrations. By considering a simple rule that allocates the energy flow from nutrient acquisition to cell structure (biomass) and cell maturity (biological complexity, eventually leading to cell division), the model is able to reproduce the co-variation of growth rate and cell size observed in the laboratory when these nutrients become limiting. These results support ongoing efforts to interpret coccosphere and coccolith size measurements in the context of climate change. [ABSTRACT FROM AUTHOR]- Published
- 2015
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10. A scrutiny of the evidence for pressure-induced state shifts in estuarine and nearshore ecosystems.
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Mac Nally, Ralph, Albano, Christine, and Fleishman, Erica
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GLOBAL environmental change ,MARINE ecology ,ESTUARIES ,MARINE resources conservation ,BIODIVERSITY conservation - Abstract
The concept of nonlinear, sudden responses of ecosystems or species to environmental change has engendered significant interest in the past two decades. Many reviews and theoretical papers have addressed alternative states or stable states, regime shifts, tipping points and phase shifts, but the empirical evidence for these phenomena, which we refer to as stark changes, has not been evaluated in estuaries and nearshore marine ecosystems. We developed standard definitions for these phenomena and examined the functional forms of ecological responses to environmental pressures (i.e. proximate influences on ecosystem state). We searched for publications related to estuaries and nearshore marine ecosystems that included common descriptors of stark change in their keywords. Our search yielded 376 papers, of which we retained 98 that met four criteria: (1) claimed a stepped biological change; (2) inferred change from empirical data; (3) addressed changes that occurred in one or more semi-enclosed, tidally influenced ecosystems; and (4) described a connection to long-term patterns of ecological change. Although there were many instances of changes in ecological states, most were not stark changes. Evidence generally was not derived from time-series data, and many studies inferred temporal change from spatial differences. We describe the eight studies that provided some evidence of stark changes in ecosystem state. We suggest that compelling evidence of stark changes that can be related to pressures requires concurrent time-series data on the ecological response and pressures that were claimed to induce the stark changes. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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11. Capturing Multidimensionality: What does a Human Wellbeing Conceptual Framework Add to the Analysis of Vulnerability?
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Sumner, Andy and Mallett, Richard
- Published
- 2013
12. Statistical modelling of collocation uncertainty in atmospheric thermodynamic profiles.
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Fassò, A., Ignaccolo, R., Madonna, F., and Demoz, B. B.
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COLLOCATION methods ,ATMOSPHERIC thermodynamics ,GLOBAL environmental change ,HETEROSCEDASTICITY ,REGRESSION analysis - Abstract
The uncertainty of important atmospheric parameters is a key factor for assessing the uncertainty of global change estimates given by numerical prediction models. One of the critical points of the uncertainty budget is related to the collocation mismatch in space and time among different observations. This is particularly important for vertical atmospheric profiles obtained by radiosondes or LIDAR. In this paper we consider a statistical modelling approach to understand at which extent collocation uncertainty is related to environmental factors, height and distance between the trajectories. To do this we introduce a new statistical approach, based on the heteroskedastic functional regression (HFR) model which extends the standard functional regression approach and allows us a natural definition of uncertainty profiles. Moreover, using this modelling approach, a five-folded uncertainty decomposition is proposed. Eventually, the HFR approach is illustrated by the collocation uncertainty analysis of relative humidity from two stations involved in GCOS reference upper-air network (GRUAN). [ABSTRACT FROM AUTHOR]
- Published
- 2013
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13. Editorial: The response of microalgae and plankton to climate change and human activities.
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Zhaohe Luo, Kieng Soon Hii, Yanpei Zhuang, and Mohamed, Hala F.
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PLANKTON ,MICROALGAE ,MARINE ecosystem health ,GLOBAL environmental change ,MARINE biology ,DUNALIELLA ,COCCOLITHUS huxleyi - Published
- 2024
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14. “Connecting Better and Wider”: A Constructivist Grounded Theory and Situational Analysis Exploration of Community Resilience in the Anthropocene Among the Transition Network.
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Boisvert, Deanne M. and Suransky, Carolina
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GLOBAL environmental change ,GROUNDED theory - Abstract
For decades qualitative researchers have used grounded theory methodologies in their investigations. Although the grounded theory literature is extensive, less well documented are qualitative studies which incorporate complementary grounded theory approaches into their designs; or studies that validate the use of grounded theory strategies for applied research projects. This paper seeks to add to both margins of the grounded theory literature. First, it provides a detailed methodological account of how constructivist grounded theory and grounded theory situational analysis were used in a Ph.D. study exploring how ecologically concerned networks understand community resilience and respond to current and anticipated challenges of the Anthropocene, the idea that humans are now the primary influencers of global environmental changes. This account is based on a constructivist grounded theory analysis of nine interviews with Europeans active in the Transition Network at the community or regional level; and a grounded theory situational analysis of the network’s written discourse based on twenty-two English-language texts produced by prominent Transitioners, such as founders, headquarters staff, or national hub teams. Furthermore, while the wider Ph.D. study focused on theory building, analysis activities yielded practical insights into addressing real world problems, such as creating and sustaining collective action at the local level. Hence, the paper also discusses a framework that neighborhoods, towns, or other types of communities could adapt for their own collective purposes. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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15. Integration degree of China's the new development pattern of dual circulation and industrial green development.
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He, Jianlin
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SUSTAINABLE development ,GLOBAL environmental change ,INDUSTRIALIZATION ,CLIMATE change ,INDUSTRIAL pollution - Abstract
The long-standing development pattern dominated by international circulation makes China face the risk of "low-end lock-in" and "being decoupling". In addition, the current global climate change and environmental crisis are becoming increasingly severe, coupled with the COVID-19 impact. Chinese enterprises must actively build a green development system for domestic industries in a mutually reinforcing manner in the context of the domestic general circulation, in order to adapt to the new dual circulation environment as soon as possible. This paper analyzes the specific coupling and coordination relationship between the two systems based on the relevant data of China's three major industries from 2008–2014 using Index DEA, entropy value method, gray correlation analysis and coupling coordination model. The results of the study show that: the two systems of dual circulation pattern and industrial green development have a strong correlation and basically present a coupling relationship, but within the industry, there is a problem of the collapse of the tertiary industry. In terms of the type of coupling, the domestic and international circulation in general gradually present the green development leading state, except for the primary industrial segment of the international circulation. On the whole, the coupling quality of the two systems needs to be further improved. Based on this, this paper puts forward the following suggestions: (1) coordinate the internal and external development of the industry; (2) take innovation as the driving force to promote the green transformation of industries; (3) take green sharing as the goal to strengthen the policy orientation of green development; (4) take the opportunity of mutual promotion of dual circulation to stabilize the steady state of green development coupling. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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16. Exploring the relationship between plural values of nature, human well‐being, and conservation and development intervention: Why it matters and how to do it?
- Author
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Carmenta, Rachel, Zaehringer, J. G., Balvanera, P., Betley, E., Dawson, N. M., Estrada‐Carmona, N., Forster, J., Hoelle, J., Lliso, B., Llopis, J. C., Menon, A., Moeliono, M., Mustin, K., Pascual, U., Rai, N. D., Schleicher, J., Shelton, C., Sigouin, A., Sterling, E. J., and Steward, A. M.
- Subjects
ENVIRONMENTAL justice ,WELL-being ,GLOBAL environmental change ,FORUMS ,CONSERVATION projects (Natural resources) ,LANDSCAPE changes ,SUSTAINABILITY - Abstract
Globally, land and seascapes across the bioculturally diverse tropics are in transition. Impacted by the demands of distant consumers, the processes of global environmental change and numerous interventions seeking climate, conservation and development goals, these transitions have the potential to impact the relationships and plurality of values held between people and place.This paper is a Synthesis of seven empirical studies within the Special Feature (SF): 'What is lost in transition? Capturing the impacts of conservation and development interventions on relational values and human wellbeing in the tropics'. Through two Open Forum workshops, and critical review, contributing authors explored emergent properties across the papers of the SF. Six core themes were identified and are subsumed within broad categories of: (i) the problem of reconciling scale and complexity, (ii) key challenges to be overcome for more plural understanding of social dimensions of landscape change and (iii) ways forward: the potential of an environmental justice framework, and a practical overview of methods available to do so.The Synthesis interprets disparate fields and complex academic work on relational values, human well‐being and de‐colonial approaches in impact appraisal. It offers a practical and actionable catalogue of methods for plural valuation in the field, and reflects on their combinations, strengths and weaknesses.The research contribution is policy relevant because it builds the case for why a more plural approach in intervention design and evaluation is essential for achieving more just and sustainable futures, and highlights some of the key actions points deemed necessary to achieve such a transition to conventional practice. Read the free Plain Language Summary for this article on the Journal blog. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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17. Species Richness and Diversity of Aquatic Ecosystems: Lessons from a Special Issue.
- Author
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Kotov, Alexey A. and Van Damme, Kay
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AQUATIC biodiversity ,SPECIES diversity ,PHYLOGEOGRAPHY ,BIOLOGICAL classification ,ECOSYSTEMS ,INTRODUCED species ,GLOBAL environmental change - Abstract
In contrast, in more southern regions, in the Transbaikalian Area, " I the branchiopod community in shallow steppe water bodies has been unchanged since at least the Pleistocene, demonstrating long-term morphological and ecological stasis i " [[15]]. Primary research focusing on aquatic biodiversity and ecosystem functioning is key to prioritizing interventions and to safeguard life in and around water. Aquatic ecosystems around the world are under increasing pressure from human activities and global warming, either directly or indirectly. Although the topics of the aforementioned set of papers are very diverse, we believe that the selection is a reflection of recent approaches to the studies of species richness and diversity of aquatic ecosystems. [Extracted from the article]
- Published
- 2022
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18. Fifteen Years of Integrated Terrestrial Environmental Observatories (TERENO) in Germany: Functions, Services, and Lessons Learned.
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Zacharias, Steffen, Loescher, Henry W., Bogena, Heye, Kiese, Ralf, Schrön, Martin, Attinger, Sabine, Blume, Theresa, Borchardt, Dietrich, Borg, Erik, Bumberger, Jan, Chwala, Christian, Dietrich, Peter, Fersch, Benjamin, Frenzel, Mark, Gaillardet, Jérôme, Groh, Jannis, Hajnsek, Irena, Itzerott, Sibylle, Kunkel, Ralf, and Kunstmann, Harald
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TECHNOLOGICAL progress ,EARTH system science ,GLOBAL environmental change ,OBSERVATORIES ,ECOLOGICAL forecasting ,AGRICULTURAL innovations ,ATMOSPHERIC boundary layer ,WATER demand management - Abstract
The need to develop and provide integrated observation systems to better understand and manage global and regional environmental change is one of the major challenges facing Earth system science today. In 2008, the German Helmholtz Association took up this challenge and launched the German research infrastructure TERrestrial ENvironmental Observatories (TERENO). The aim of TERENO is the establishment and maintenance of a network of observatories as a basis for an interdisciplinary and long‐term research program to investigate the effects of global environmental change on terrestrial ecosystems and their socio‐economic consequences. State‐of‐the‐art methods from the field of environmental monitoring, geophysics, remote sensing, and modeling are used to record and analyze states and fluxes in different environmental disciplines from groundwater through the vadose zone, surface water, and biosphere, up to the lower atmosphere. Over the past 15 years we have collectively gained experience in operating a long‐term observing network, thereby overcoming unexpected operational and institutional challenges, exceeding expectations, and facilitating new research. Today, the TERENO network is a key pillar for environmental modeling and forecasting in Germany, an information hub for practitioners and policy stakeholders in agriculture, forestry, and water management at regional to national levels, a nucleus for international collaboration, academic training and scientific outreach, an important anchor for large‐scale experiments, and a trigger for methodological innovation and technological progress. This article describes TERENO's key services and functions, presents the main lessons learned from this 15‐year effort, and emphasizes the need to continue long‐term integrated environmental monitoring programmes in the future. Plain Language Summary: This paper discusses the importance of creating comprehensive environmental observation systems to better understand and address global and regional environmental changes. In 2008, a German research infrastructure named Terrestrial Environmental Observatories (TERENO) was established to build and maintain a network of observatories. The goal is to conduct interdisciplinary, long‐term research on the impacts of global environmental changes on terrestrial ecosystems and their socio‐economic effects. The TERENO network employs advanced methods from environmental monitoring, geophysics, remote sensing, and modeling to study various environmental aspects. Over the past 15 years, four observatories have been part of this network, contributing to valuable experience in overcoming challenges and exceeding expectations. Today, TERENO is a crucial component for environmental modeling and forecasting in Germany, serving as an information hub for practitioners and policymakers. It also fosters international collaboration, supports large‐scale experiments, and drives methodological and technological advancements. The article highlights key lessons learned from this 15‐year effort and emphasizes the importance of continuing such integrated environmental monitoring programs in the future. Key Points: Integrated observatories ensure a holistic Earth Systems perspective, offering data for current and future ecological challengesThe scientific and societal value of observatories is invaluable, but their design, construction and operation require considerable effortFor assured long‐term data collection, research infrastructure must have flexible design for adapting to changing research needs [ABSTRACT FROM AUTHOR]
- Published
- 2024
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19. Application of clustering techniques to study environmental characteristics of microbialite-bearing aquatic systems.
- Author
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Dalinina, R., Petryshyn, V. A., Lim, D. S., Braverman, A. J., and Tripati, A. K.
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STROMATOLITES ,GLOBAL environmental change ,AQUATIC ecology ,WATER alkalinity ,ANIONS - Abstract
Microbialites are a product of trapping and binding of sediment by microbial communities, and are considered to be some of the most ancient records of life on Earth. It is a commonly held belief that microbialites are limited to extreme, hypersaline settings. However, more recent studies report their occurrence in a wider range of environments. The goal of this study is to explore whether microbialite-bearing sites share common geochemical properties. We apply statistical techniques to distinguish any common traits in these environments. These techniques ultimately could be used to address questions of microbialite distribution: are microbialites restricted to environments with specific characteristics; or are they more broadly distributed? A dataset containing hydrographic characteristics of several microbialite sites with data on pH, conductivity, alkalinity, and concentrations of several major anions and cations was constructed from previously published studies. In order to group the water samples by their natural similarities and differences, a clustering approach was chosen for analysis. k means clustering with partial distances was applied to the dataset with missing values, and separated the data into two clusters. One of the clusters is formed by samples from atoll Kiritimati (central Pacific Ocean), and the second cluster contains all other observations. Using these two clusters, the missing values were imputed by k nearest neighbor method, producing a complete dataset that can be used for further multivariate analysis. Salinity is not found to be an important variable defining clustering, and although pH defines clustering in this dataset, it is not an important variable for microbialite formation. Clustering and imputation procedures outlined here can be applied to an expanded dataset on microbialite characteristics in order to determine properties associated with microbialite-containing environments. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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20. An open and extensible framework for spatially explicit land use change modelling in R: the lulccR package (0.1.0).
- Author
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Moulds, S., Buytaert, W., and Mijic, A.
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BIODIVERSITY ,LAND use ,GLOBAL environmental change ,CLIMATE change ,ATMOSPHERIC temperature - Abstract
Land use change has important consequences for biodiversity and the sustainability of ecosystem services, as well as for global environmental change. Spatially explicit land use change models improve our understanding of the processes driving change and make predictions about the quantity and location of future and past change. Here we present the lulccR package, an object-oriented framework for land use change modelling written in the R programming language. The contribution of the work is to resolve the following limitations associated with the current land use change modelling paradigm: (1) the source code for model implementations is frequently unavailable, severely compromising the reproducibility of scientific results and making it impossible for members of the community to improve or adapt models for their own purposes; (2) ensemble experiments to capture model structural uncertainty are difficult because of fundamental differences between implementations of different models; (3) different aspects of the modelling procedure must be performed in different environments because existing applications usually only perform the spatial allocation of change. The package includes a stochastic ordered allocation procedure as well as an implementation of the widely used CLUE-S algorithm. We demonstrate its functionality by simulating land use change at the Plum Island Ecosystems site, using a dataset included with the package. It is envisaged that lulccR will enable future model development and comparison within an open environment. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
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21. Potential and limitations of finite element modelling in assessing structural integrity of coralline algae under future global change.
- Author
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Melbourne, L. A., Griffin, J., Schmidt, D. N., and Rayfield, E. J.
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CORALLINE algae ,HABITATS ,FINITE element method ,GLOBAL environmental change ,ALGAL growth ,ALGAE ecology ,COMPUTED tomography - Abstract
Coralline algae are important habitat formers found on all rocky shores. While the impact of future ocean acidification on the physiological performance of the species has been well studied, little research has focussed on potential changes in structural integrity in response to climate change. A previous study using 2-D Finite Element Analysis (FEA), suggested increased vulnerability to fracture (by wave action or boring) in algae grown under high CO
2 conditions. To assess how realistically 2-D simplified models represent structural performance, a series of increasingly biologically accurate 3-D FE-models that represent coralline algal growth were developed. Simplified geometric 3-D models of the genus Lithothamnion were compared to models created from computed tomography (CT) scan data of the same genus. The biologically accurate model and the simplified geometric model representing individual cells had similar average stresses and stress distributions, emphasizing the importance of the cell walls in dissipating the stress throughout the structure. In contrast models without the accurate representation of the cell geometry resulted in larger stress and strain results. Our more complex 3-D model reiterated the potential of climate change to diminish the structural integrity of the organism. This suggests that under future environmental conditions the weakening of the coralline algal skeleton along with increased external pressures (wave and bioerosion) may negatively influence the ability for coralline algae to maintain a habitat able to sustain high levels of biodiversity. [ABSTRACT FROM AUTHOR]- Published
- 2015
- Full Text
- View/download PDF
22. Differential responses of seabirds to inter-annual environmental change in the continental shelf and oceanic habitats of southeastern Bering Sea.
- Author
-
Yamamoto, T., Kokubun, N., Kikuchi, D. M., Sato, N., Takahashi, A., Will, A., Kitaysky, A. S., and Watanuki, Y.
- Subjects
SEA birds ,GLOBAL environmental change ,CONTINENTAL shelf ,HABITATS - Abstract
Seasonal sea-ice cover has been decreasing in the southeastern Bering Sea shelf, which might affect ecosystem dynamics and availability of food resources to marine top predators breeding in the region. In this study, we investigated the foraging responses of two seabird species, surface-foraging red-legged kittiwakes Rissa brevirostris (hereafter, RLKI) and pursuit-diving foraging thick-billed murres Uria lomvia (TBMU) to the inter-annual change in environmental conditions. Between the study years, winter ice retreated earlier and summer water temperatures were warmer in 2014 compared to those in 2013. At-sea distributions of RLKI and TBMU breeding on St. George Island, the largest seabird colony in the region, were recorded using GPS loggers, and blood samples were taken to examine their physiological condition and isotopic foraging niche in a given year. RLKI foraging occurred mostly over the oceanic basin in both years. TBMU, however, foraged mostly over the shelf, but showed a relatively higher use of the shelf break and oceanic basin in the colder year, 2013. The foraging distances from the colony peaked at 250-300 km in 2013 and, bimodally, at 150-250 and 300-350 km in 2014 for RLKI, and tended to be farther in 2013 compared to those in 2014 for TBMU. Plasma levels of corticosterone did not differ between years in RLKI, but differed in TBMU, showing higher levels of physiological stress incurred by murres during the colder year, 2013. d
13 N (a proxy of trophic level of prey) did not differ between the years in either RLKI or TBMU, while d13 C (a proxy of prey origin) were lower in 2014 than in 2013 in both species, suggesting possible differences in influx of oceanic prey items into foraging areas. These results suggest that the response of ecosystem dynamics to climate variability in the southeast Bering Sea may differ between the ocean basin and continental shelf regions, which, in turn, may generate differential responses in seabirds relying on those habitats for foraging. [ABSTRACT FROM AUTHOR]- Published
- 2015
- Full Text
- View/download PDF
23. Current Status of the Main Olive Pests: Useful Integrated Pest Management Strategies and Genetic Tools.
- Author
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Lantero, Esther, Matallanas, Beatriz, and Callejas, Carmen
- Subjects
INTEGRATED pest control ,GLOBAL environmental change ,OLIVE fly ,PESTICIDE resistance ,PESTS ,PESTICIDES - Abstract
Mediterranean olive cultivation faces challenges in the global environmental change context. Pests and diseases caused by arthropods such as Bactrocera oleae, Prays oleae, and certain vectors of Xylella fastidiosa are expected to increase and spread in part due to this global scenario. The control of these arthropods has relied on synthetic pesticides, the misuse of which has led to pest population resistance and concerns about their negative impacts on biodiversity and global health. Integrated pest management (IPM) methods have emerged through the careful consideration of all available control techniques and the subsequent integration of appropriate measures that discourage the development of pest populations. This paper reviews the IPM guidelines for olive cultivation, prioritizing the use of biological control methods, and the integration of genetics and biotechnology, which bring precision, efficacy, and safety. It evidences the importance of genetic analysis in pest populations, pesticide resistance and in the contributions of predators to pest control. Advances in formulations and delivery systems for pesticides such as Bacillus thuringiensis, plant-incorporated protectants, improved SIT techniques, and the specific efficacy of biologicals pesticides are covered. Finally, this paper explores promising tools such as RNAi and gene drive while recognizing the ethical, environmental, and regulatory challenges associated with their use. Shortly, these innovations have the potential to reduce the environmental impacts of pests while ensuring the long-term viability of the olive industry. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
24. Novelty, Rigor, and Diversity
- Author
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Holling, C.S. (Buzz)
- Published
- 1998
25. Fine-root biomass and fluxes of soil carbon in young stands of paper birch and trembling aspen as affected by elevated atmospheric CO2 and tropospheric O3.
- Author
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King, J. S., Pregitzer, K. S., Zak, D. R., Sober, J., Isebrands, J. G., Dickson, R. E., Hendrey, G. R., and Karnosky, D. F.
- Subjects
GLOBAL environmental change ,ECOLOGY ,CARBON sequestration ,CARBON compounds ,BIOMASS - Abstract
Rising atmospheric CO
2 may stimulate future forest productivity, possibly increasing carbon storage in terrestrial ecosystems, but how tropospheric ozone will modify this response is unknown. Because of the importance of fine roots to the belowground C cycle, we monitored fine-root biomass and associated C fluxes in regenerating stands of trembling aspen, and mixed stands of trembling aspen and paper birch at FACTS-II, the Aspen FACE project in Rhinelander, Wisconsin. Free-air CO2 enrichment (FACE) was used to elevate concentrations of CO2 (average enrichment concentration 535 µl l–1 ) and O3 (53 nl l–1 ) in developing forest stands in 1998 and 1999. Soil respiration, soil pCO2 , and dissolved organic carbon in soil solution (DOC) were monitored biweekly. Soil respiration was measured with a portable infrared gas analyzer. Soil pCO2 and DOC samples were collected from soil gas wells and tension lysimeters, respectively, at depths of 15, 30, and 125 cm. Fine-root biomass averaged 263 g m–2 in control plots and increased 96% under elevated CO2 . The increased root biomass was accompanied by a 39% increase in soil respiration and a 27% increase in soil pCO2 . Both soil respiration and pCO2 exhibited a strong seasonal signal, which was positively correlated with soil temperature. DOC concentrations in soil solution averaged ~12 mg l–1 in surface horizons, declined with depth, and were little affected by the treatments. A simplified belowground C budget for the site indicated that native soil organic matter still dominated the system, and that soil respiration was by far the largest flux. Ozone decreased the above responses to elevated CO2 , but effects were rarely statistically significant. We conclude that regenerating stands of northern hardwoods have the potential for substantially greater C input to soil due to greater fine-root production under elevated CO2 . Greater fine-root biomass will be accompanied by greater soil C efflux as soil respiration, but leaching losses of C will probably be unaffected. [ABSTRACT FROM AUTHOR]- Published
- 2001
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- View/download PDF
26. A Behavioural Approach to Strategic Management.
- Author
-
BALATON, KÁROLY
- Subjects
STRATEGIC planning ,ORGANIZATIONAL behavior ,DECISION making ,REASON ,GLOBAL environmental change - Abstract
The concepts, methods and practices of strategic management have evolved significantly since the beginning of the 20th century. In the 1950s and 60s the use of long-term planning was characteristic. Until the end of the 1980s strategy was perceived as a response to environmental changes. During the 1990s strategy formulation was perceived as a process based on internal resources and capabilities of firms. This radical change with the previously applied concepts was influenced by the accelerated rate of environmental changes. Companies - especially large firms - were unable to change their strategies parallel with changes in their environment. They needed a more stable starting point for developing their strategies. Strategic decision makers intended to make optimal strategic decisions until the end of the 70s. Due to the newly emerged theory of limited rationality it has become accepted as a strong influencing factor of strategic decisionmaking. Parallel with the above mentioned changes the role of managerial behavioural characteristic had emerged as a more broadly accepted factor in strategic decision-making. In the present paper our intention is to present this development process. In preparing the paper the author has relied on his previous publications in the field. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
27. Social innovation that connects people to coasts in the Anthropocene.
- Author
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Celliers, Louis, Mañez Costa, María, Rölfer, Lena, Aswani, Shankar, and Ferse, Sebastian
- Subjects
SOCIAL action ,SOCIAL innovation ,GLOBAL environmental change ,ECOSYSTEMS ,POSTINDUSTRIAL societies ,COASTS ,SOCIAL systems - Abstract
Post-industrial society is driving global environmental change, which is a challenge for all generations, current and future. The Anthropocene is the geological epoch in which humans dominate and it is rooted in the past, present, and future. Future sustainability is building on the momentum of the fundamental importance of studying human dynamics and governance of coupled social and ecological systems. In the Anthropocene, social innovation may play a critical role in achieving new pathways to sustainability. This conventional narrative review uses a qualitative analysis anchored in the Grounded Theory Method and a systematic collection and analysis of papers to identify broad types of social innovations. Scientific journal articles published since 2018 were prioritised for inclusion. The six types of social innovation proposed are (a) authentic engagement; (b) artful and engaging communication; (c) urging and compelling change; (d) governance for social-ecological systems; (e) anticipation in governance; and (f) lived experiences and values. The six innovations proposed in this paper can be embedded within, and form part of, social action using a science-society compact for the sustainable development of coasts in the Anthropocene. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
28. Water use strategies of a young Eucalyptus urophylla forest in response to seasonal change of climatic factors in South China.
- Author
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Zhang, Z. Z., Zhao, P., Oren, R., McCarthy, H. R., Niu, J. F., Zhu, L. W., Ni, G. Y., and Huang, Y. Q.
- Subjects
EUCALYPTUS ,WATER use ,CLIMATE change ,STOMATA ,GLOBAL environmental change - Abstract
To depict the wet (April with a soil water content, SWC, of 37%) and dry (October with a SWC of 24.8%) seasonal changes in the water use and physiological response of a Eucalyptus urophylla plantation in subtropical South China characterized by monsoon climate, the whole-year (June 2012 to May 2013) transpiration of E. urophylla was monitored using the TDP method. Daily transpiration (ET) in October averaged 5.7 ± 2.9 kgd
-1 and was 58.0% higher than that in April (3.6 ± 2.3 kgd-1 ). The difference is consistent with that of the radiation and evaporative demand of the two months, while the nocturnal transpiration (ET-NOC ) in the wet season (0.18 ± 0.021 kgd-1 ) was almost twice that in the dry season (0.11 ±0.01 kgd-1 ). Trees displayed a higher stomatal conductance (GS ) (53.4-144.5 mmolm-2 s-1 ) in the wet season and a lower GS (45.7-89.5 mmol m-2 s-1 ) in the dry season. The leaf-soil water potentials (YL ) of the two months (April and October) were - 0.62 ±0.66 and -1.22 ±0.10 MPa, respectively. A boundary line analysis demonstrated that the slight improvement in the GS by SWC in wet season was offset by a significant decrease in D, and the slope of GS sensitivity to D (dGS/dlnD) in response to GSef (references GS at D = 1 kPa) was affected by the variance of radiation instead of SWC. Specific hydraulic conductivity (ks ) of trees of different sizes decreased by 45.3-65.6% from the wet to the dry season. Combining the decreased maximum reference GS at D = 1 kPa (GSref-max ) by 22.4% with the constant max GS (GSmax ) when YL < -1.2 MPa, we shed some light on the mechanism underlying the high water-use efficiency (WUE) of this Eucalyptus specie. With a slight change in GSref-max and high sensitivity of ks to decreasing ΨL , large trees used water more efficiently than small ones did. In addition, the -m in the dry season (0.53±0.007) was lower than that in the wet season (0.58 ± 0.01) due to the difference in the ratio of GS to the boundary layer conductance (gb) in the two months. The negative relationship between -m (except when light is limited) and Q proved to be a plastic response to environmental changes for E. urophylla but did not change with decreased ks as expected. [ABSTRACT FROM AUTHOR]- Published
- 2015
- Full Text
- View/download PDF
29. Global assessment of Vegetation Index and Phenology Lab (VIP) and Global Inventory Modeling and Mapping Studies (GIMMS) version 3 products.
- Author
-
Marshall, M., Okuto, E., Kang, Y., Opiyo, E., and Ahmed, M.
- Subjects
VEGETATION monitoring ,PHENOLOGY ,GLOBAL modeling systems ,GLOBAL environmental change ,RAIN forests ,CLIMATOLOGY - Abstract
Earth observation based long-term global vegetation index products are used by scientists from a wide range of disciplines concerned with global change. Inter-comparison studies are commonly performed to keep the user community informed on the consistency and accuracy of such records as they evolve. In this study, we compared two new records: (1) Global Inventory Modeling and Mapping Studies (GIMMS) Normalized Difference Vegetation Index Version 3 (NDVI3g) and (2) Vegetation Index and Phenology Lab (VIP) Version 3 NDVI (NDVI3v) and Enhanced Vegetation Index 2 (EVI3v). We evaluated the two records via three experiments that addressed the primary use of such records in global change research: (1) prediction of the Leaf Area Index (LAI) used in light-use efficiency modeling, (2) estimation of vegetation climatology in Soil- Vegetation-Atmosphere Transfer models, and (3) trend analysis of the magnitude and phenology of vegetation productivity. Experiment one, unlike previous inter-comparison studies, was performed with a unique Landsat 30m spatial resolution and in situ LAI database for major crop types on five continents. Overall, the two records showed a high level of agreement both in direction and magnitude on a monthly basis, though VIP values were higher and more variable and showed lower correlations and higher error with in situ LAI. The records were most consistent at northern latitudes during the primary growing season and southern latitudes and the tropics throughout much of the year, while the records were less consistent at northern latitudes during green-up and senescence and in the great deserts of the world throughout much of the year. The two records were also highly consistent in terms of trend direction/magnitude, showing a 30+ year increase (decrease) in NDVI over much of the globe (tropical rainforests). The two records were less consistent in terms of timing due to the poor correlation of the records during start and end of growing season. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
30. Apparent optical properties of the Canadian Beaufort Sea -- Part 1: Observational overview and water column relationships.
- Author
-
Antoine, D., Hooker, S. B., Belanger, S., Matsuoka, A., and Babin, M.
- Subjects
RADIOMETRY ,GLOBAL environmental change ,SCIENTIFIC observation ,PHOTOSYNTHESIS ,REMOTE sensing ,OPTICAL properties of water - Abstract
A data set of radiometric measurements collected in the Beaufort Sea (Canadian Arctic) in August 2009 (MALINA project) is analysed in order to describe apparent optical properties (AOPs) in this sea, which is subject to dramatic environmental changes for several decades. The two properties derived from the measurements are the spectral diffuse attenuation coefficient for downward irradiance, K
d , and the spectral remote sensing reflectance, Rrs . The former controls light propagation in the upper water column. The latter determines how light is backscattered out of the water and becomes eventually observable from a satellite ocean colour sensor. The data set includes offshore clear waters of the Beaufort basin as well as highly turbid waters of the Mackenzie River plumes. In the clear waters, we show Kd values that are much larger in the ultraviolet and blue parts of the spectrum than what could be anticipated considering the chlorophyll concentration. A larger contribution of absorption by coloured dissolved organic matter (CDOM) is responsible for this high Kd values, as compared to other oligotrophic areas. In turbid waters, attenuation reaches extremely high values, driven by high loads of particulate materials and also by a large CDOM content. In these two extreme types of waters, current satellite chlorophyll algorithms fail. This is questioning the role of ocean colour remote sensing in the Arctic when Rrs from only the blue and green bands are used. Therefore, other parts of the spectrum (e.g. the red) should be explored if one aims at quantifying interannual changes in chlorophyll in the Arctic from space. The very peculiar AOPs in the Beaufort Sea also advocate for developing specific light propagation models when attempting to predict light availability for photosynthesis at depth. [ABSTRACT FROM AUTHOR]- Published
- 2013
- Full Text
- View/download PDF
31. Predicting decadal trends and transient responses of radiocarbon storage and fluxes in a temperate forest soil.
- Author
-
Sierra, C. A., Trumbore, S. E., Davidson, E. A., Frey, S. D., Savage, K. E., and Hopkins, F. M.
- Subjects
CARBON isotopes ,HEAT flux ,FOREST soils ,CARBON in soils ,GLOBAL environmental change ,PREDICTION models ,BIODEGRADATION ,FOREST management - Abstract
Representing the response of soil carbon dynamics to global environmental change requires the incorporation of multiple tools in the development of predictive models. An important tool to construct and test models is the incorporation of bomb radiocarbon in soil organic matter during the past decades. In this manuscript, we combined radiocarbon data and a previously developed empirical model to explore decade-scale soil carbon dynamics in a temperate forest ecosystem at the Harvard Forest, Massachusetts, USA. We evaluated the contribution of different soil C fractions to both total soil CO
2 efflux and microbially-respired C. We tested the performance of the model based on measurable soil organic matter fractions against a decade of radiocarbon measurements. The model was then challenged with radiocarbon measurements from a warming and N addition experiment to test multiple hypotheses about the different response of soil C fractions to the experimental manipulations. Our results showed that the empirical model satisfactorily predicts the trends of radiocarbon in litter, density fractions, and respired CO2 observed over a decade in the soils not subjected to manipulation. However, the model, modified with prescribed relationships for temperature and decomposition rates, predicted most but not all the observations from the field experiment where soil temperatures and nitrogen levels were increased, suggesting that a larger degree of complexity and mechanistic relations need to be added to the model to predict short-term responses and transient dynamics. [ABSTRACT FROM AUTHOR]- Published
- 2012
- Full Text
- View/download PDF
32. Ideas and perspectives: use of tree-ring width as an indicator of tree growth.
- Author
-
Hember, R. A., Kurz, W. A., and Metsaranta, J. M.
- Subjects
TREE-rings ,TREE growth ,BIOINDICATORS ,GLOBAL environmental change ,ENVIRONMENTAL impact analysis - Abstract
By taking core samples, dendroecological studies can reconstruct radial growth over the lifespan of a tree, providing a valuable way to estimate the sensitivity of tree productivity to environmental change. With increasing prevalence of such studies in global change science, it is worth cautioning that the incremental growth rate of a sub-dimension of a tree organ, such as annual ring width (w), does not respond to extrinsic perturbations with the same relative magnitude as the primary production of that organ. For example, if an extrinsic force causes a two-fold increase in the absolute growth rate of stemwood biomass (AGR), it should only theoretically translate into a 1.3-fold increase in w, or a 1.7-fold increase in basal area increment (BAI), when a 2 : 1 ratio in resource allocation to lateral and apical meristems is assumed. Expressing the magnitude of a response in relative terms does not, therefore, provide a valid means of comparing estimates of relative growth derived from measurement of different dimensional traits of the tree. From our perspective, enough conformity to facilitate comparison of environmental sensitivity across studies of tree growth is warranted so we emphasize the benefit of dimension analysis to transform measurements of w and BAI into the AGR. Although conversion to AGR introduces an error from the use of allometric equations, the approach is widely accepted in mainstream ecology and global change science at least partially because it avoids discrepancies in response magnitude owing to differences in dimension. Studies of organ elongation have historically provided invaluable information, yet it must be recognized that they systematically underestimate the response magnitude of primary production, and confound comparisons of growth sensitivity between many dendroecological studies that focus on w and studies of primary production. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
33. Impacts and mass extinctions: papers in honour of Glen Caldwell.
- Author
-
Copper, Paul and Jin, Jisuo
- Subjects
- *
ENVIRONMENTAL sciences , *ECOLOGY , *GLOBAL environmental change , *PERIODICALS , *EARTH sciences - Abstract
Introduces a series of articles regarding the impact of the mass extinction of rare and exotic species on global environment and evolution, published in the 1999 issue "Canadian Journal of Earth Sciences."
- Published
- 2001
- Full Text
- View/download PDF
34. Speciation and dynamics of dissolved inorganic nitrogen export in the Danshui River, Taiwan.
- Author
-
T. -Y. Lee, Y. -T. Shih, J. -C. Huang, S. -J. Kao, F. -K. Shiah, and K. -K. Liu
- Subjects
CHEMICAL speciation ,NITROGEN supersaturation ,GLOBAL environmental change ,AQUATIC ecology - Abstract
Dissolved inorganic nitrogen (DIN, including ammonium, nitrite and nitrate) export from land to ocean is becoming dominated by anthropogenic activities and severely altering the aquatic ecosystem. However, rare observational analyses have been conducted in the Oceania, the hotspot of global DIN export. In this study a whole watershed monitoring network (20 stations) was conducted in 2003 to investigate the controlling factors of DIN export in the Danshui River of Taiwan. The results showed that DIN concentration ranged from ~ 16 μM in the headwater and up to ~ 430 μM in the estuary. However, the dominating DIN species transformed gradually from NO
3 - in the headwater (~ 97%) to NH4 + in the estuary (~ 70%), which well followed the descending dissolved oxygen (DO) distribution (from ~ 8 mg L-1 to ~ 1 mg L-1 ). NO2 - was observed in the transition zone from high to low DO. DIN yield was increasing downstream, ranging from ~ 160 to ~ 6000 kg N km-2 yr-1 as population density increases toward the estuary, from ~ 15 pop km-2 to ~ 2600 pop km-2 . Although the individual DIN export, ~ 2.40 kg N person-1 yr-1 , was comparable to the global average, the close-to-top DIN yield was observed owing to abundant rainfall, dense population, and the sensitive response to population increase. The Danshui River occupies 1.8 x 10-3 % of the land surface area of the Earth but discharges disproportionately high percentage, ~ 60 x 10-3 % (~ 14 000 t N yr-1 ) of the annual global DIN export to the ocean. Through this study, regulating factors and the significance of human population on DIN export were identified, and the regional databases were supplemented to promote the completeness of global models. [ABSTRACT FROM AUTHOR]- Published
- 2014
- Full Text
- View/download PDF
35. Composition and sources of sedimentary organic matter in the deep Eastern Mediterranean Sea.
- Author
-
Pedrosa-Pàmies, R., Parinos, C., Sanchez-Vidal, A., Gogou, A., Calafat, A., Canals, M., Bouloubassi, I., and Lampadariou, N.
- Subjects
MARINE sediments ,GLOBAL environmental change ,BIOGEOCHEMISTRY ,CLUSTERING of particles - Abstract
Surface sediments collected from deep slopes and basins (1018-4087m depth) of the oligotrophic Eastern Mediterranean Sea have been analysed for bulk elemental and isotopic composition of organic carbon, total nitrogen and selected lipid biomarkers, jointly with grain size distribution and other geochemical proxies. The distribution and sources of sedimentary organic matter (OM) have been subsequently assessed and general environmental variables, such as water depth and currents, have been examined as causative factors of deep-sea sediment characteristics. Lithogenic and biogenic carbonates are the dominant sedimentary fractions, while both bulk and molecular organic tracers reflect a mixed contribution from autochthonous and allochthonous sources for the sedimentary OM, as indicated by relatively degraded marine OM, terrestrial plant waxes and anthropogenic OM including degraded petroleum by-products, respectively. Wide regional variations have been observed amongst the studied proxies, which reflect the multiple factors controlling sedimentation in the deep Eastern Mediterranean Sea. Our findings highlight the role of deep Eastern Mediterranean basins as depocentres of organic-rich fine-grained sediments (mean 5.4±2.4 µm), with OM accumulation and burial due to aggregation mechanisms and hydrodynamic sorting. A multi-proxy approach is hired to investigate the biogeochemical composition of sediment samples, which sheds new light on the sources and transport mechanisms along with the impact of preservation vs. diagenetic processes on the composition of sedimentary OM in the deep basins of the oligotrophic Eastern Mediterranean Sea. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
36. The Invisible Prevalence of Citizen Science in Global Research: Migratory Birds and Climate Change.
- Author
-
Cooper, Caren B., Shirk, Jennifer, and Zuckerberg, Benjamin
- Subjects
CITIZENS ,BIRD migration ,CLIMATE change ,DATA analysis ,ORNITHOLOGISTS ,GLOBAL environmental change ,ANIMAL classification - Abstract
Citizen science is a research practice that relies on public contributions of data. The strong recognition of its educational value combined with the need for novel methods to handle subsequent large and complex data sets raises the question: Is citizen science effective at science? A quantitative assessment of the contributions of citizen science for its core purpose – scientific research – is lacking. We examined the contribution of citizen science to a review paper by ornithologists in which they formulated ten central claims about the impact of climate change on avian migration. Citizen science was never explicitly mentioned in the review article. For each of the claims, these ornithologists scored their opinions about the amount of research effort invested in each claim and how strongly the claim was supported by evidence. This allowed us to also determine whether their trust in claims was, unwittingly or not, related to the degree to which the claims relied primarily on data generated by citizen scientists. We found that papers based on citizen science constituted between 24 and 77% of the references backing each claim, with no evidence of a mistrust of claims that relied heavily on citizen-science data. We reveal that many of these papers may not easily be recognized as drawing upon volunteer contributions, as the search terms “citizen science” and “volunteer” would have overlooked the majority of the studies that back the ten claims about birds and climate change. Our results suggest that the significance of citizen science to global research, an endeavor that is reliant on long-term information at large spatial scales, might be far greater than is readily perceived. To better understand and track the contributions of citizen science in the future, we urge researchers to use the keyword “citizen science” in papers that draw on efforts of non-professionals. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
37. Small diversity effects on ocean primary production under environmental change in a diversity-resolving ocean ecosystem model.
- Author
-
Prowe, A. E. F., Pahlow, M., Dutkiewicz, S., and Oschlies, A.
- Subjects
MARINE ecology ,PRIMARY productivity (Biology) ,GLOBAL environmental change ,PHYTOPLANKTON ,MATHEMATICAL models ,SENSITIVITY analysis - Abstract
Marine ecosystem models used to investigate how global change affects ocean ecosystems and their functioning typically omit pelagic diversity. Diversity, however, can affect functions such as primary production and their sensitivity to environmental changes. Using a global ocean ecosystem model that explicitly resolves phytoplankton diversity within four phytoplankton functional types (PFTs) we investigate the model's ability to capture diversity effects on primary production under environmental change. An idealized scenario with a sudden reduction in vertical mixing causes diversity and primary-production changes that turn out to be largely independent of the number of coexisting phytoplankton types. The model provides a small number of niches with respect to nutrient use in accordance with the PFTs defined in the model, and increasing the number of phytoplankton types increases the resolution within the niches. The variety of traits and trade-offs resolved in the model constrains diversity effects such as niche complementarity, which operate between, but not within PFTs. The number and nature of the niches formulated in the model, for example via trade-offs or different PFTs, thus determines the diversity effects on ecosystem functioning captured in ocean ecosystem models. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
38. Soil greenhouse gas fluxes from different tree species on Taihang Mountain, North China.
- Author
-
X. P. Liu, W. J. Zhang, C. S. Hu, and X. G. Tang
- Subjects
FORESTS & forestry ,PLANT species ,GREENHOUSE gas mitigation ,GLOBAL environmental change ,BLACK locust ,POMEGRANATE ,SOIL temperature - Abstract
The objectives of this study were to investigate seasonal variation of greenhouse gas fluxes from soils on sites dominated by plantation (Robinia pseudoacacia, Punica granatum, and Ziziphus jujube) and natural regenerated forests (Vitex negundo var. heterophylla, Leptodermis oblonga, and Bothriochloa ischcemum), and to identify how tree species, litter exclusion, and soil properties (soil temperature, soil moisture, soil organic carbon, total N, soil bulk density, and soil pH) explained the temporal and spatial variance in soil greenhouse gas fluxes. Fluxes of greenhouse gases were measured using static chamber and gas chromatography techniques. Six static chambers were randomly installed in each tree species. Three chambers were randomly designated to measure the impacts of surface litter exclusion, and the remaining three were used as a control. Field measurements were conducted biweekly from May 2010 through April 2012. Soil CO
2 emissions from all tree species were significantly affected by soil temperature, soil moisture, and their interaction. Driven by the seasonality of temperature and precipitation, soil CO2 emissions demonstrated a clear seasonal pattern, with fluxes significantly higher during the rainy season than during the dry season. Soil CH4 and N2 O fluxes were not significantly correlated with soil temperature, soil moisture, or their interaction, and no significant seasonal differences were detected. Soil CO2 and N2 O fluxes were significantly correlated with soil organic carbon, total N, and soil bulk density, while soil pH was not correlated with CO2 and N2 O emissions. Soil CH4 fluxes did not display pronounced dependency on soil organic carbon, total N, soil bulk density, and soil pH. Removal of surface litter resulted in significant decreases in CO2 emissions and CH4 uptakes, but had no significant influence on N2 O fluxes. Soils in six tree species acted as sinks for atmospheric CH4 . With the exception of Ziziphus jujube, Soils in all sites acted as sinks for atmospheric N2 O. Tree species had a significant effect on CO2 and N2 O fluxes but not on CH4 uptake. The lower net global warming potential in natural regenerated vegetation suggested that natural regenerated vegetation were more desirable plant species in reducing global warming. [ABSTRACT FROM AUTHOR]- Published
- 2013
- Full Text
- View/download PDF
39. Modelling soil organic carbon stocks in global change scenarios: a CarboSOIL application.
- Author
-
Munoz-Rojas, M., Jordán, A., Zavala, L. M., González-Penaloza, F. A., De la Rosa, D., and Anaya-Romero, M.
- Subjects
CARBON in soils ,GLOBAL environmental change ,ATMOSPHERIC carbon dioxide ,CARBON sequestration ,PREDICTION models ,DECISION support systems - Abstract
Global climate change, as a consequence of the increasing levels of atmospheric CO
2 concentration, may significantly affect both soil organic C storage and soil capacity for C sequestration. In this research we develop a methodology to predict soil organic C (SOC) contents and changes under global change scenarios. CarboSOIL model is a new component of the land evaluation decision support system MicroLEIS, which was designed to assist decision makers to face specific agro-ecological problems. CarboSOIL, developed as a GIS tool to predict SOC contents at different depths, was previously trained and tested in two Mediterranean areas: Andalusia (SW Spain) and Valencia (E Spain). The model was applied under different IPPC scenarios (A1B, A2 and B1) according to different global climate models (BCCR-BCM2, CNRMCM3 and ECHAM5) and output data were linked to spatial datasets (soil and land use) to quantify SOC stocks. CarboSOIL model has proved its ability to predict the short-, medium- and long-term trends (2040s, 2070s and 2100s) of SOC dynamics and sequestration under projected future scenarios of climate change. Results showed an overall trend towards decreasing of SOC stocks in the upper soil sections (0-25 cm and 25-50 cm) for most soil types and land uses, but predicted SOC stocks tend to increase in the deeper soil section (50-75 cm). Soil types as Arenosols, Planosols and Solonchaks and land uses as "permanent crops" and "open spaces with little or no vegetation" would be severely affected by climate change with large decreases of SOC stocks, in particular under the medium-high emission scenario A2 by 2100. The information developed in this study might support decision-making in land management and climate adaptation strategies in Mediterranean regions and the methodology could be applied to other Mediterranean areas with available soil, land use and climate data. [ABSTRACT FROM AUTHOR]- Published
- 2013
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40. A new dataset for systematic assessments of climate change impacts as a function of global warming.
- Author
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Heinke, J., Ostberg, S., Schaphoff, S., Frieler, K., Müller, C., Gerten, D., Meinshausen, M., and Lucht, W.
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CLIMATE change ,GLOBAL temperature changes ,ATMOSPHERIC models ,PHYSIOLOGICAL adaptation ,GLOBAL environmental change - Abstract
The article presents a newly composed dataset of climate change scenario to pacify requirements for global assessments of climate change impacts. It is evident that global mean temperature change has become the yardstick to gauze impact of unavoidable climate change and requirement of adaptation. It is informed that the dataset helps in analyzing impact of climate change and implement climate model.
- Published
- 2012
- Full Text
- View/download PDF
41. Environmental change impacts on the C- and N-cycle of European forests: a model comparison study.
- Author
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Cameron, D. R., Van Oijen, M., Werner, C., Butterbach-Bahl, K., Haas, E., Heuvelink, G. B. M., Grote, R., Kiese, R., Kuhnert, M., Kros, J., Leip, A., Reinds, G. J., Reuter, H. I., Schelhaas, M. J., De Vries, W., and Yeluripati, J.
- Subjects
GLOBAL environmental change ,ENVIRONMENTAL impact analysis ,CARBON cycle ,NITROGEN cycle ,FORESTS & forestry ,COMPARATIVE studies - Abstract
Forests are important components of the greenhouse gas balance of Europe. There is considerable uncertainty about how predicted changes to climate and nitrogen deposition will perturb the carbon and nitrogen cycles of European forests and thereby alter forest growth, carbon sequestration and N
2 O emission. The present study aimed to quantify the carbon and nitrogen balance, including the exchange of greenhouse gases, of European forests over the period 2010-2030, with a particular emphasis on the spatial variability of change. The analysis was carried out for two tree species: European beech and Scots pine. For this purpose, four different dynamic models were used: BASFOR, Daily Day Cent, INTEGRATOR and Landscape-DNDC. These models span a range from semi-empirical to complex mechanistic. Comparison of these models allowed assessment of the extent to which model predictions depended on differences in model inputs and structure. We found a European average carbon sink of 0.160±0.020 kgCm-2 yr-1 (pine) and 0.138 ±0.062 kgCm-2 yr-1 (beech) and N2 O source of 0.285 ±0.125 kgNha-1 yr-1 (pine) and 0.575 ±0.105 kgNha-1 yr-1 (beech). The European average greenhouse gas potential of the carbon source was 18 (pine) and 8 (beech) times that of the N2 O source. Carbon sequestration was larger in the trees than in the soil. Carbon sequestration and forest growth were largest in central Europe and lowest in northern Sweden and Finland, N. Poland and S. Spain. No single driver was found to dominate change across Europe. Forests were found to be most sensitive to change in environmental drivers where the drivers were limiting growth, where changes were particularly large or where changes acted in concert. The models disagreed as to which environmental changes were most significant for the geographical variation in forest growth and as to which tree species showed the largest rate of carbon sequestration. Pine and beech forests were found to have differing sensitivities to environmental change, in particular the response to changes in nitrogen and precipitation, with beech forest more vulnerable to drought. There was considerable uncertainty about the geographical location of N2 O emissions. Two of the models BASFOR and Landscape DNDC had largest emissions in central Europe where nitrogen deposition and soil nitrogen were largest whereas the two other models identified different regions with large N2 O emission. N2 O emissions were found to be larger from beech than pine forests and were found to be particularly sensitive to forest growth. [ABSTRACT FROM AUTHOR]- Published
- 2012
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- View/download PDF
42. Interactive effects of vertical mixing, nutrients and ultraviolet radiation: in situ photosynthetic responses of phytoplankton from high mountain lakes of Southern Europe.
- Author
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Helbling, E. W., Carrillo, P., Medina-Sanchez, J. M., Durán, C., Herrera, G., Villar-Argaiz, M., and Villafañe, V. E.
- Subjects
ULTRAVIOLET radiation ,PHOTOSYNTHESIS ,PHYTOPLANKTON ,GLOBAL environmental change ,BODIES of water ,SOLAR radiation - Abstract
Global change, together with human activities had resulted in increasing amounts of organic material (including nutrients) received by water bodies. This input further attenuates the penetration of solar radiation leading to the view that opaque lakes are more "protected" from solar ultraviolet radiation (UVR) than clear ones. Vertical mixing, however, complicates this view as cells are exposed to fluctuating radiation regimes, which effects have in general been neglected. Even more, the combined impacts of mixing, together with those of UVR and nutrients input are virtually unknown. In this study, we carried out in situ experiments in three high mountain lakes of Spain (Lake Enol in Asturias, and lakes Las Yeguas and La Caldera in Granada) to determine the combined effects of these three variables associated to global change on photosynthetic responses of natural phytoplankton communities. The experimentation consisted in all possible combinations of the following treatments: (a) solar radiation: UVR+PAR (280-700 nm) versus PAR alone (400-700 nm); (b) nutrient addition (phosphorus (P) and nitrogen (N)): ambient versus addition (P to reach to a final concentration of 30 µgPl
-1 , and N to reach a N: P molar ratio of 31) and, (c) mixing: mixed (one rotation from surface to 3m depth (speed of 1 m every 4 min, total of 10 cycles) versus static. Our findings suggest that under in situ nutrient conditions there is a synergistic effect between vertical mixing and UVR, increasing phytoplankton photosynthetic inhibition and EOC from opaque lakes as compared to algae that received constant mean irradiance within the epilimnion. The opposite occurs in clear lakes where antagonistic effects were determined, with mixing partially counteracting the negative effects of UVR. Nutrients input mimicking atmospheric pulses from Saharan dust, reversed this effect and clear lakes became more inhibited during mixing, while opaque lakes benefited from the fluctuating irradiance regime. These climate change-related nutrients input and increased mixing would not only affect photosynthesis and production of lakes, but might also further influence the microbial loop and trophic interactions via enhanced EOC under fluctuating UVR exposure. [ABSTRACT FROM AUTHOR]- Published
- 2012
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- View/download PDF
43. Dissolved inorganic carbon and alkalinity fluxes from coastal marine sediments: model estimates for different shelf environments and sensitivity to global change.
- Author
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Krumins, V., Gehlen, M., Arndt, S., van Cappellen, P., and Regnier, P.
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ALKALINITY ,MARINE sediments ,GLOBAL environmental change ,CARBON dioxide ,DIFFUSION ,BIOTURBATION ,SENSITIVITY analysis - Abstract
We present a one-dimensional reactive transport model to estimate benthic fluxes of dissolved inorganic carbon (DIC) and alkalinity (A
T ) from coastal marine sediments. The model incorporates the transport processes of sediment accumulation, molecular diffusion, bioturbation and bioirrigation, while the reactions included are the redox pathways of organic carbon oxidation, re-oxidation of reduced nitrogen, iron and sulfur compounds, pore water acid-base equilibria, and dissolution of particulate inorganic carbon (calcite, aragonite, and Mg-calcite). The coastal zone is divided into four environmental units with different particulate inorganic carbon (PIC) and particulate organic carbon (POC) fluxes: reefs, banks and bays, carbonate shelves and non-carbonate shelves. Model results are analyzed separately for each environment and then scaled up to the whole coastal ocean. The model-derived estimate for the present-day global coastal benthic DIC efflux is 126 Tmolyr-1 , based on a global coastal reactive POC depositional flux of 117 Tmolyr-1 . The POC decomposition leads to a carbonate dissolution from shallow marine sediments of 7 Tmolyr-1 (on the order of 0.1 PgCyr-1 ). Assuming complete re-oxidation of aqueous sulfide released from sediments, the effective net flux of alkalinity to the water column is 29 Teqyr-1 , primarily from PIC dissolution (46 %) and ammonification (33%). Because our POC depositional flux falls in the high range of global values given in the literature, the reported DIC and alkalinity fluxes should be viewed as upper-bound estimates. Increasing coastal seawater DIC to what might be expected in year 2100 due to the uptake of anthropogenic CO2 increases PIC dissolution by 2.3 Tmolyr-1 and alkalinity eflux by 4.8 Teqyr-1 . Our reactive transport modeling approach not only yields global estimates of benthic DIC, alkalinity and nutrient fluxes under variable scenarios of ocean productivity and chemistry, but also provides insights into the underlying processes. [ABSTRACT FROM AUTHOR]- Published
- 2012
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- View/download PDF
44. Synthesizing greenhouse gas fluxes across nine European peatlands and shrublands -- responses to climatic and environmental changes.
- Author
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Carter, M. S., Larsen, K. S., Emmett, B., Estiarte, M., Field, C., Leith, I. D., Lund, M., Meijide, A., Mills, R. T. E., Niinemets, Ü., Peñuelas, J., Portillo-Estrada, M., Schmidt, I. K., Selsted, M. B., Sheppard, L. J., Sowerby, A., Tietema, A., and Beier, C.
- Subjects
GREENHOUSE gases ,PEATLANDS ,SHRUBLANDS ,GLOBAL environmental change ,METHANE ,NITROUS oxide ,SOIL respiration - Abstract
In this study, we compare annual fluxes of methane (CH4), nitrous oxide (N2O) and soil respiratory carbon dioxide (CO2) measured at nine European peatlands (n = 4) and shrublands (n = 5). The sites range from northern Sweden to Spain, covering a span in mean annual air temperature from 0 to 16 C, and in annual precipitation from 300 to 1300mmyr-1. The effects of climate change, including temperature increase and prolonged drought, were tested at five shrubland sites. At one peatland site, the longterm (> 30 yr) effect of drainage was assessed, while increased nitrogen deposition was investigated at three peatland sites. The shrublands were generally sinks for atmospheric CH4 whereas the peatlands were CH4 sources, with fluxes ranging from -519 to +6890mg CH4-Cm-2 yr-1 across the studied ecosystems. At the peatland sites, annual CH4 emission increased with mean annual air temperature, while a negative relationship was found between net CH4 uptake and the soil carbon stock at the shrubland sites. Annual N2O fluxes were generally small ranging from -14 to 42mg N2O-Nm-2 yr-1. Highest N2O emission oc- curred at the sites that had highest concentration of nitrate (NO-3 ) in soil water. Furthermore, experimentally increased NO-3 deposition led to increased N2O efflux, whereas prolonged drought and long-term drainage reduced the N2O efflux. Soil CO2 emissions in control plots ranged from 310 to 732 g CO2-Cm-2 yr-1. Drought and long-term drainage generally reduced the soil CO2 efflux, except at a hydric shrubland where drought tended to increase soil respiration. When comparing the fractional importance of each greenhouse gas to the total numerical global warming response, the change in CO2 efflux dominated the response in all treatments (ranging 71--96 %), except for NO-3 addition where 89% was due to change in CH4 emissions. Thus, in European peatlands and shrublands the feedback to global warming induced by the investigated anthropogenic disturbances will be dominated by variations in soil CO2 fluxes. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
45. Response of Nodularia spumigena to pCO2 -- Part I: Growth, production and nitrogen cycling.
- Author
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Wannicke, N., Endres, S., Engel, A., Grossart, H.-P., Nausch, M., Unger, J., and Voss, M.
- Subjects
CYANOBACTERIA ,CARBON dioxide ,NITROGEN cycle ,GLOBAL environmental change ,NITROGEN fixation ,STOICHIOMETRY - Abstract
Heterocystous cyanobacteria of the genus Nodularia form extensive blooms in the Baltic Sea contributing substantially to the total annual primary production. Moreover, they dispense a large fraction of new nitrogen to the ecosystem, when inorganic nitrogen concentration in summer is low. Thus, it is of great ecological importance to know how Nodularia will react to future environmental changes, in particular to increasing carbon dioxide (CO
2 ) concentrations and what consequences there might arise for cycling of organic matter in the ocean. Here, we determined carbon (C) and dinitrogen (N2 ) fixation rates, growth, elemental stoichiometry of particulate organic matter and nitrogen turnover during batch growth of the heterocystous cyanobacterium Nodularia spumigena under glacial (180 ppm), present (380 ppm), and future (780 ppm) CO2 concentrations. Our results demonstrate an overall stimulating effect of rising pCO2 on C2 and N2 fixation, as well as on cell growth. An increase in pCO2 resulted in an elevation in growth rate, C and N2 fixation by 23%, 36% and 25%, respectively (180 ppm vs. 380 ppm) and by 27%, 2% and 4%, respectively (380 ppm vs. 780 ppm). Additionally, elevation in the carbon and nitrogen to phosphorus quota of the particulate biomass formed (POC:POP and PON:POP) was observed at high pCO2 . Our findings suggest that rising pCO2 stimulates the growth of heterocystous diazotrophic cyanobacteria, in a similar way as reported for non-heterocystous diazotrophs. Implications for biogeo-chemical cycling and food web dynamics, as well as ecological and socio-economical aspects in the Baltic Sea are discussed. [ABSTRACT FROM AUTHOR]- Published
- 2012
- Full Text
- View/download PDF
46. Observations of the uptake of carbonyl sulfide (COS) by trees under elevated atmospheric carbon dioxide concentrations.
- Author
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Sandoval-Soto, L., Kesselmeier, M., Schmitt, V., Wild, A., and Kesselmeier, J.
- Subjects
METEOROLOGICAL observations ,GLOBAL environmental change ,SULFIDES ,PLANT communities ,ATMOSPHERIC carbon dioxide ,CARBOXYLASES ,PLANT species ,ATMOSPHERIC aerosols ,EUROPEAN beech ,VEGETATION & climate - Abstract
Global change affects ecosystems to adapt to elevated atmospheric concentrations of carbon dioxide (CO
2 ). We understand that carbonyl sulfide (COS), a trace gas which is involved in building up the stratospheric sulfate aerosol layer, is taken up by vegetation with the same triad of the enzmyes which are metabolizing the CO2 , i.e. Ribulose-1,5-bisphosphate Carboxylase-Oxygenase (Rubisco), Phosphoenolpyruvate Carboxylase (PEP-Co) and carbonic anhydrase (CA). Therefore, we discuss a physiological/ biochemical adaptation of these enzymes to affect the sink strength of vegetation for COS. We investigated the adaption of two European tree species, Fagus sylvatica and Quercus ilex, grown inside chambers under elevated CO2 and determined the exchange characteristics and the content of CA after a 1-2 yr period of adaption from 350 ppm to 800 ppm CO2 . We could demonstrate that the COS compensation point, the CA activity and the deposition velocities may change and cause a decrease of the COS uptake by plant ecosystems. As a consequence, the atmospheric COS level may rise leading to higher input of this trace gas into the stratosphere and causing a higher energy reflection by the stratospheric sulfur aerosol into space, thus counteracting the direct radiative forcing by the tropospheric COS. [ABSTRACT FROM AUTHOR]- Published
- 2012
- Full Text
- View/download PDF
47. Lomborg and the Litany of Biodiversity Crisis: What the Peer-Reviewed Literature Says.
- Author
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BINI, LUIS MAURICIO, ALEXANDRE, JOSÉ, DINIZ‐FILHO, FELIZOLA, CARVALHO, PRISCILLA, PINTO, MIRIAM PLAZA, and RANGEL, THIAGO FERNANDO L. V. B.
- Subjects
BIODIVERSITY ,BOOKS & reading ,GLOBAL environmental change ,SCIENTIFIC literature ,CONSERVATION of natural resources ,BIOTIC communities ,EMPIRICAL research ,ENVIRONMENTAL protection - Abstract
Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2005
- Full Text
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48. How to learn more about hydrological conditions and phytoplankton dynamics and diversity in the eastern English Channel and the Southern Bight of the North Sea: the Suivi Régional des Nutriments data set (1992–2021).
- Author
-
Lefebvre, Alain and Devreker, David
- Subjects
REGIONS of freshwater influence ,GLOBAL environmental change ,PHYTOPLANKTON ,TERRITORIAL waters ,COASTS ,WATER quality - Abstract
This article describes a 30-year data series produced by the SRN ("Suivi Régional des Nutriments" in French; Regional Nutrients Monitoring Programme) network managed by Ifremer. Since 1992, the SRN network has been analysing phytoplankton species and measuring physicochemical (temperature, salinity, oxygen, suspended matter, nutrients) and biological (chlorophyll a , phytoplankton abundance) parameters at 10 different stations distributed along three different transects located in the eastern English Channel and the Southern Bight of the North Sea. This geographic coverage allows for the study of three distinct ecosystems, i.e. three transects (estuary, coastal region under freshwater influence, and coastal region), as well as the investigation of coastal to offshore water gradients. The SRN collects a maximum of 184 samples per year (3687 samples spread over 10 stations during the studied period) and detects up to 291 taxa, including harmful algal bloom species (HABs), with a bi-weekly to monthly sampling frequency (depending on the location and the season). The objectives of this monitoring programme are to assess the influence of continental inputs on the marine environment and their implications for possible eutrophication processes. It also aims to estimate the effectiveness of development and management policies in the marine coastal zone by providing information on trends and/or shifts in pressure, state, and impact variables. The regular acquisition of data allows the establishment of long-term monitoring of the evolution of coastal water quality as well as the observation of the consequences of large-scale alterations mainly driven by climate change and modifications that are more related to local/regional anthropogenic activities. This paper provides an overview of the main characteristics of SRN data (descriptive statistics and data series main patterns) as well as an analysis of temporal trends and shifts. We also propose to the data user a specific numerical tool available as an R package to optimize the data pre-processing and processing steps. Users will then have easy access to statistics, trends, and anomalies as proposed in this paper. The main results of several research projects based on SRN data and dealing with hydrology, phytoplankton blooms, HABs, phenology, and niches are also highlighted, providing the readers with examples of what can be done with such a data set. We hope that this synthesis will also save data users time by allowing them to jump right into a deeper analysis based on previous conclusions and perspectives or to investigate new scientific key challenges. These data should also be used at a wider geographical scale, combined with other data sources, to define more global patterns of environmental changes in a moving world subject to strong anthropogenic pressures. Data can also be used by the remote sensing (ocean colour observation) and modelling communities to calibrate or validate products in this complex and vital coastal region. The SRN data set is publicly available: 10.17882/50832 (SRN – Regional Observation and Monitoring program for Phytoplankton and Hydrology in the eastern English Channel, 2022). [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
49. Direct and indirect effects of vertical mixing, nutrients and ultraviolet radiation on the bacterioplankton metabolism in high-mountain lakes from southern Europe.
- Author
-
Durán, C., Medina-Sánchez, J. M., Herrera, G., Villar-Argaiz, M., Villafañe, V. E., Helbling, E. W., and Carrillo, P.
- Subjects
VERTICAL mixing (Earth sciences) ,BACTERIOPLANKTON ,AQUATIC organisms ,GLOBAL environmental change ,AQUATIC microbiology ,BACTERIAL metabolism - Abstract
As a consequence of global change, modifications in the interaction among abiotic stressors on aquatic ecosystems have been predicted. Among other factors, UVR transparency, nutrient inputs and shallower epilimnetic layers could alter the trophic links in the microbial food web. Currently, there are some evidences of higher sensitiveness of aquatic microbial organisms to UVR in opaque lakes. Our aim was to assess the interactive direct and indirect effects of UVR (through the excretion of organic carbon -- EOC -- by algae), mixing regime and nutrient input on bacterial metabolism We performed in situ short-term experiments under the following treatments: full sunlight (UVR+ PAR, > 280 nm) vs. UVR exclusion (PAR only, > 400 nm); ambient vs. nutrient addition (phosphorus (P; 30 µg PL
-1 ) and nitrogen (N; up to final N:P molar ratio of 31)); and static vs. mixed regime. The experiments were conducted in three high-mountain lakes of Spain: Enol [LE], Las Yeguas [LY] and La Caldera [LC] which had contrasting UVR transparency characteristics (opaque (LE) vs. clear lakes (LY and LC)). Under ambient nutrient conditions and static regimes, UVR exerted a stimulatory effect on heterotrophic bacterial production (HBP) in the opaque lake but not in the clear ones. Under UVR, vertical mixing and nutrient addition HBP values were lower than under the static and ambient nutrient conditions, and the stimulatory effect that UVR exerted on HBP in the opaque lake disappeared. By contrast, vertical mixing and nutrient addition increased HBP values in the clear lakes, highlighting for a photoinhibitory effect of UVR on HBP. Mixed regime and nutrient addition resulted in negative effects of UVR on HBP more in the opaque than in the clear lakes. Moreover, in the opaque lake, bacterial respiration (BR) increased and EOC did not support the bacterial carbon demand (BCD). In contrast, bacterial metabolic costs did not increase in the clear lakes and the increased nutrient availability even led to higher HBP. Consequently, EOC satisfied BCD in the clear lakes, particularly in the clearest one [LC]. Our results suggest that the higher vulnerability of bacteria to the damaging effects of UVR may be particularly accentuated in the opaque lakes and further recognizes the relevance of light exposure history and biotic interactions on bacterioplankton metabolism when coping with fluctuating radiation and nutrient inputs. [ABSTRACT FROM AUTHOR]- Published
- 2014
- Full Text
- View/download PDF
50. Diversity of Arctic Pelagic Prokaryotes with an emphasis on photoheterotrophic bacteria: a review.
- Author
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Boeuf, D., Humily, F., and Jeanthon, C.
- Subjects
HETEROTROPHIC bacteria ,PROKARYOTES ,GLOBAL environmental change ,BIOGEOCHEMISTRY ,CLIMATE change - Abstract
The Arctic Ocean is a unique marine environment with respect to seasonality of light, temperature, perennial ice cover and strong stratification. Other important distinctive features are the influence of extensive continental shelves and its interactions with Atlantic and Pacific water masses and freshwater from sea ice melt and rivers. These characteristics have major influence on the biological and biogeochemical processes occurring in this complex natural system. Heterotrophic bacteria are crucial components of marine food webs and have key roles in controlling carbon fluxes in the oceans. Although it was previously thought that these organisms relied on the organic carbon in seawater for all of their energy needs, several recent discoveries now suggest that pelagic bacteria can depart from a strictly heterotrophic lifestyle by obtaining energy through unconventional mechanisms that are linked to the penetration of sunlight into surface waters. These photoheterotrophic mechanisms may play a significant role in the energy budget in the euphotic zone of marine environments. We can suspect that this role could be of greater importance in the Arctic Ocean where environmental changes triggered by climate change could favor the photoheterotrophic lifestyle. Here we review advances in our knowledge of the diversity of marine photoheterotrophic bacteria and discuss their significance in the Arctic Ocean gained in the framework of the Malina cruise. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
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