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The change of regional land use structure has important influence on the stability of ecosystem structure and function. As a typical representative of resource-based cities in central of China, original land use structure was changed because of industrial transformation and upgrading in Taiyuan, which has become a key link in ecological environment construction. Using the Environment for Visualizing Images (ENVI), this paper calculates the ecological quality metrics of Taiyuan in the process of industrial transformation and upgrading, and explores the response of ecological quality in Taiyuan to the spatiotemporal evolution of land use structure. The results show that: (1) From 2003 to 2018, the proportion of urban construction land in east and south of Taiyuan continued to increase. (2) The ecological quality of Taiyuan improved generally. The most obvious improvement was achieved in the Fenhe River Valley. Some parts of the valley changed from strongly bad area (RSEI: 0.2–0.4) to strongly good area (RSEI: 0.8–1.0). (3) The ecological quality in Taiyuan was distributed unevenly in space. In 2013, the ecological quality in the south was poorer than that in 2003 and 2008. However, the ecological quality in that region showed a significant rebound in 2018. The research results shed important new light on urban land use structure, ecological quality evaluation, and formulation of ecological protection policies.

This chapter summarizes key ecological issues, synthesizes key integrating variables, and identifies critical issues for future study. Insect ecology includes both insect adaptations to their environment and their effects on environmental conditions. Insects represent the full scope of heterotrophic adaptive life history strategies, from sessile species whose ecological strategies resemble those of plants to social insects whose range of behavioral attributes resembles that of advanced vertebrates. Insects, as well as other organisms, influence their environment in complex, and often dramatic, ways, earning many species the designation of “ecosystem engineers.” The hierarchical organization of this study emphasizes linkages and feedbacks among levels of ecological organization. Linkages and feedbacks are strongest between neighboring levels but are significant even between individual and ecosystem levels of the hierarchy. Adaptations for detecting and acquiring resources are highly developed among insects. Many insects can detect the presence and location of resources from chemical cues, which are carried at low concentrations on wind or water currents. Along with this, ecosystems represent the level at which complex feedbacks among abiotic and biotic processes are integrated. Ecosystems can be viewed as dynamic energy- and nutrient-processing engines that modify global energy and nutrient fluxes.

This chapter discusses controls over ecosystem structure and function, which is a complicated topic, and offers some general observations about ecosystem controls that can be used in both scientific studies and management contexts. Control is defined, and several reasons why this topic occupies a central position in ecosystem science is discussed. Also, a few of the more important conclusions that ecosystem scientists have reached about how ecosystems are controlled are covered.

This research is part of POLARCSIC activities.-- 15 pages, 9 figures, 3 tables, supplementary data https://doi.org/10.1016/j.jmarsys.2019.103268, The flow of non-living carbon (detritus) is considered an important process because it connects ecosystems and fuels benthic communities. In Norwegian kelp forests, 90% of the kelp production is exported to adjacent ecosystems where it can play a significant role in shaping benthic communities. We quantified the major structural and functional traits of an Arctic deep-sea ecosystem associated with kelp exports and assessed the ecological role of kelp export into the deep-sea system. We first developed a food-web model using the Ecopath with Ecosim (EwE) approach to represent the state of the deep (450 m) ecosystem of the Malangen fjord (Northern Norway) in 2017. Subsequently, we used the temporal dynamic model Ecosim to explore the structure and functioning traits of a theoretical deep-sea ecosystem projecting a decrease of kelp detritus biomass reaching the deep-sea ecosystem. Overall, our findings reveal that kelp detritus from shallow coastal areas has a small but noticeable role structuring the deep-sea ecosystem of Malangen. The temporal simulations show important differences depending on the application of mediating effects, which allow considering the detritus as a mediating group in prey-predator interaction, in addition to its direct role in trophic relationships. When mediating effects are applied, biomass increases for benthopelagic shrimps and suprabenthos groups and decreases for rays and skates, velvet belly, rabbitfish and other commercial demersal fishes under the low kelp detritus scenarios. Biomass-based and trophic-based indicators reveal a noticeable impact on the deep-sea ecosystem structure due to depletion of kelp detritus. To further assess future changes of the Arctic deep-sea ecosystems, dependencies with adjacent ecosystems, such as kelp detritus production, should be included, This work was funded by MARINFORSK Norwegian Research Council through the KELPEX project (NRC Grant no. 255085/E40). [...] MC acknowledges partial funding by the European Union's Horizon research program grant agreement No 689518 for the MERCES project, With the funding support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), of the Spanish Research Agency (AEI)

Contemporary mining creates environments that differ from preexisting conditions, yet those preexisting conditions are expected to be largely re-established during reclamation. As public awareness of impacts of mining increases, regulatory and public expectations of the mining industry advance concurrently. As a consequence, environmental laws that regulate the mining industry have become more complex and challenging. Miners are expected to produce reclaimed mine lands that will support economically viable postmining land uses while protecting environmental quality and, for some uses, to re-establish ecosystem structure and processes that often resembles the premining conditions. It is clear that effective reclamation must be fully integrated with mining operations. Successful reclamation demands engineering, design, and careful reconstruction of the full mining disturbance; and mitigation of mining effects on the land surface, air, and water. A capability to produce lands that can support viable postmining use and sustainable ecosystem processes, as needed to satisfy regulatory requirements, is crucial to the long-term success and profitability of the mining industry. This chapter provides an overview of mine reclamation methods that can be utilized to restore land use capability and environmental quality. Because the experience of the authors is primarily in the USA's Appalachian region, reclamation practices of that region are emphasized. In accord with the book's theme, special consideration is given to reclamation and water management practices that can address emerging regulatory and environmental management challenges that are being faced by the mining industry.

Aquatic mesocosms and microcosms (cosms) are model experimental systems, designed to be representative of specific ecosystems, e.g., small freshwater ponds or lakes. They contain populations and communities of organisms at multiple trophic levels that interact with their environment and each other. In ecotoxicology, they can be used to study the direct and indirect effects of chemicals and other stressors on ecosystem structure and function, recovery from these effects, and to inform ecological risk assessment.

There is increasing concern over the loss of regulating services, which are the benefits obtained from regulatory ecosystem processes. Many regulating services are not marketed, and often there is inadequate knowledge to link changes in ecosystem structure and function to the production of these valuable benefits. These measurement issues are important limitations to the valuation of regulating services. An example of mangrove conversion to shrimp farming in Thailand illustrates the importance of valuing regulating services in land use decisions. Progress has also been made in integrated ecological-economic modelling to determine the value of multiple ecosystem services, including regulating benefits.

Dry subtropical regions, originally hosting xerophytic vegetation, are currently characterized by diverse land cover/use patterns. Using existing biophysical and socio-economic databases, we explored how human contexts influenced land cover, vegetation composition and agricultural production in five distant regions. On average, cultivated areas represented a minor proportion (

Publisher Summary There are two ways in which marine mammals and their ecosystems can interact. One encompasses the effects of the ecosystem on marine mammals; the other, the effects of marine mammals on their ecosystems. Ocean scientists in general and marine mammalogists in particular often consider their worlds from the former perspective. Significant ecological effects of marine mammals are implied from their great abundance, high trophic status, high metabolic rates, and the resulting fact that some of these consumers co-opt great proportions of their ecosystem's primary production. Many marine mammal species have been depleted through overexploitation for protein, oil, and other products. A few others have increased dramatically in recent years due to protection from human harassment or perhaps other factors. If marine mammals are important drivers of ecosystem structure and function, the ecological effects resulting from these changes in their abundance could be substantial.

Existing theories are used to predict responses to anthropogenic changes in riverine ecosystems, but explicit hypotheses on ecosystem behavior in altered landscapes have not been incorporated into these models. This chapter describes the types of responses expected in altered riverine ecosystems as defined by the tenets of the RES. Disturbances changing attributes in one domain will alter attributes of others through secondary or tertiary mechanisms. This chapter addresses broad changes in the nature of riverine ecosystems through direct actions on attributes and provides examples of deviations from expected patterns. The tenets of the riverine ecosystem synthesis (RES) are presented by considering how they can be used to predict changes/responses from population to landscape levels. The tenets provide a framework for applying the RES in situations encountered in altered systems and for understanding how changes in the characteristics of an FPZ influence ecosystem structure and function independent of location along a longitudinal gradient of a riverine ecosystem. A goal of this chapter is to provide key policy makers and river managers with better tools for environmental management and rehabilitation of riverine landscapes.

Publisher Summary This chapter focuses on the less well-documented interactions between silicon and nitrogen in the marine environment across a variety of scales. Toward the end, this review of Si:N interactions focuses primarily on diatoms, starting with newly available genomic information, and continuing on to a review of cellular Si-metabolism, emphasizing interactions with other cellular constituents. This leads naturally to a discussion of physiological and ecophysiological Si:N interactions, with an emphasis on the (un)coupling of Si-metabolism from photosynthesis and C:N assimilation, as well as the modulating effects of trace-metal interactions such as Fe and Zn. The role of Si:N interactions in controlling export production and biogeochemical cycling, both in the modern and paleo ocean is then discussed. Further, there is increasing evidence for fundamental changes in ecosystem structure in response to shifts from diatoms to other organisms as previously predicted. While these shifts in ecosystem structure are not necessarily negative, the long-term consequences of anthropogenic influences on Si:N dynamics are likely to be an overall decrease in fisheries production and an increase in noxious and harmful algal species.

This chapter focuses on ecosystem structure. Ecosystem can be viewed as how the sun's energy is captured and passed from plants to animals and then from animals to animals and the strategies that animals have evolved to capture a share of that energy, use it, and flourish in the Gulf of Alaska. Marine animals thrive in the Gulf of Alaska (GOA) for two basic reasons: (1) the ecosystem is productive, and a lot of food is available to animals living there, and (2) a small number of successful species in the Gulf made the most of the available energy by organizing themselves, as revolving body forms, physiology, and behaviors that allow them to successfully withstand the rigors of the subarctic ocean, capture food, grow, and reproduce faster than they themselves are eaten, harvested, or fall victims to contaminants or disease. The chapter explores the changing structure of the ecosystem during a typical year. The survival strategies of the key species of fish, birds, and mammals that tie them to their habitats are also discussed.

The unique physical characteristics of Arctic and Antarctic polynyas often make them highly productive marine environments. Here I focus on four major polynyas (the NEW and NOW polynyas in the Arctic and the Ross Sea and Mertz Glacier polynyas in the Antarctic) and compare and contrast the major physicochemical features that control rates of phytoplankton growth and primary production in each. Included in this analysis are the effects of temperature, solar radiation (including ultraviolet), and nutrient delivery. Also discussed is the positive feedback that exists between cloud cover and polynya size as well as the importance of the timing of polynya formation on ecosystem structure.

It has been proposed that the Gulf of Guinea Large Marine Ecosystem can be divided into three subsystems, however, the limits of this system and its constituent subsystems have only been defined arbitrarily. This study uses principal components analysis to investigate the variance structure of remotely sensed SST data for the Gulf of Guinea in an attempt to define important ecosystem structures and boundaries using the natural variability of the system. The results are interpreted in terms of underlying physical dynamics and boundaries of the large marine ecosystem and its subsystems are determined. Inter and intra-comparison of SST in these new subsystems is then used to successfully validate the new subsystems.

“Critical loads” have been defined as the highest deposition of compounds that will not cause chemical changes leading to long-term harmful effects on ecosystem structure and function. European maps of critical loads of acidity, sulphur and nitrogen have been produced to assess the sensitivity of forest soils and surface waters. These maps can be compared with present and projected levels of pollutant emissions, allowing assessment of the effects of various emission abatement strategies. Parts of central and northwest Europe currently receive 20 times or more acidity than their critical loads, thus affecting the long-term sustainability of these ecosystems. It is shown that stringent emission reductions are needed to protect large parts of European forests and surface waters against acidification.

Publisher Summary This chapter discusses the findings from the acidification of forests in the Netherlands (ACIFORN) monitoring projects and from a number of related projects carried out as part of the Dutch Priority Programme on Acidification. The results are used to evaluate hypotheses on possible cause, mechanisms, and effects of forest decline under conditions in the Netherlands. The hypotheses relate to traditional factors, to effects of ozone, to combined effects of SO2, NOx, and NH3, to soil acidification, and to excess nitrogen deposition. An intensive monitoring programme can have a twofold aim: to describe and analyze internal ecosystem structure from a functional point of view and to provide a comparative analysis of comparable monitoring carried out under different conditions. Within ACIFORN, the main emphasis has been on the description and analysis of internal system structure and the accompanying functional relationships. Hence, the ACIFORN results alone cannot be used to compare processes in stands at different stages of decline; they merely serve to increase the understanding of forest functioning under ambient levels of air pollution and soil acidification.

The most successful models of marsh/estuarine systems are more than an academic exercise in summarizing large data sets. They are also useful tools for formulating new testable hypotheses, for guiding large ecosystem-level research programs and for guiding the management of coastal habitats. Reviewed here are six simulation models of coastal marsh/estuarine systems that are representative of both management-and research-directed efforts. The authors exemplify the diversity of objectives, approaches and usefulness of these models. The utility of sensitivity analysis as a means to reveal factors controlling certain ecosystem behaviors is analyzed and shown to be strongly limited by the initial abstraction or conceptualization of the ecosystem structure.