Search

Old-growth tropical forests harbor an immense diversity of tree species but are rapidly being cleared, while secondary forests that regrow on abandoned agricultural lands increase in extent. We assess how tree species richness and composition recover during secondary succession across gradients in environmental conditions and anthropogenic disturbance in an unprecedented multisite analysis for the Neotropics. Secondary forests recover remarkably fast in species richness but slowly in species composition. Secondary forests take a median time of five decades to recover the species richness of old-growth forest (80% recovery after 20 years) based on rarefaction analysis. Full recovery of species composition takes centuries (only 34% recovery after 20 years). A dual strategy that maintains both old-growth forests and species-rich secondary forests is therefore crucial for biodiversity conservation in human-modified tropical landscapes.

The high species richness of tropical forests has long been recognized, yet there remains substantial uncertainty regarding the actual number of tropical tree species. Using a pantropical tree inventory database from closed canopy forests, consisting of 657,630 trees belonging to 11,371 species, we use a fitted value of Fisher's alpha and an approximate pantropical stem total to estimate the minimum number of tropical forest tree species to fall between ∼ 40,000 and ∼ 53,000, i.e., at the high end of previous estimates. Contrary to common assumption, the Indo-Pacific region was found to be as species-rich as the Neotropics, with both regions having a minimum of ∼ 19,000-25,000 tree species. Continental Africa is relatively depauperate with a minimum of ∼ 4,500-6,000 tree species. Very few species are shared among the African, American, and the Indo-Pacific regions. We provide a methodological framework for estimating species richness in trees that may help refine species richness estimates of tree-dependent taxa.

Wetlands are valuable ecosystems because they harbor a huge biodiversity and provide key services to societies. When natural or human factors degrade wetlands, ecological restoration is often carried out to recover biodiversity and ecosystem services (ES). Although such restorations are routinely performed, we lack systematic, evidence-based assessments of their effectiveness on the recovery of biodiversity and ES. Here we performed a meta-analysis of 70 experimental studies in order to assess the effectiveness of ecological restoration and identify what factors affect it. We compared selected ecosystem performance variables between degraded and restored wetlands and between restored and natural wetlands using response ratios and random-effects categorical modeling. We assessed how context factors such as ecosystem type, main agent of degradation, restoration action, experimental design, and restoration age influenced post-restoration biodiversity and ES. Biodiversity showed excellent recovery, though the precise recovery depended strongly on the type of organisms involved. Restored wetlands showed 36% higher levels of provisioning, regulating and supporting ES than did degraded wetlands. In fact, wetlands showed levels of provisioning and cultural ES similar to those of natural wetlands; however, their levels of supporting and regulating ES were, respectively, 16% and 22% lower than in natural wetlands. Recovery of biodiversity and of ES were positively correlated, indicating a win-win restoration outcome. The extent to which restoration increased biodiversity and ES in degraded wetlands depended primarily on the main agent of degradation, restoration actions, experimental design, and ecosystem type. In contrast, the choice of specific restoration actions alone explained most differences between restored and natural wetlands. These results highlight the importance of comprehensive, multi-factorial assessment to determine the ecological status of degraded, restored and natural wetlands and thereby evaluate the effectiveness of ecological restorations. Future research on wetland restoration should also seek to identify which restoration actions work best for specific habitats.

Over the past several decades, a rapidly expanding field of research known as biodiversity and ecosystem functioning has begun to quantify how the world's biological diversity can, as an independent variable, control ecological processes that are both essential for, and fundamental to, the functioning of ecosystems. Research in this area has often been justified on grounds that (1) loss of biological diversity ranks among the most pronounced changes to the global environment and that (2) reductions in diversity, and corresponding changes in species composition, could alter important services that ecosystems provide to humanity (e.g., food production, pest/disease control, water purification). Here we review over two decades of experiments that have examined how species richness of primary producers influences the suite of ecological processes that are controlled by plants and algae in terrestrial, marine, and freshwater ecosystems. Using formal meta-analyses, we assess the balance of evidence for eight fundamental questions and corresponding hypotheses about the functional role of producer diversity in ecosystems. These include questions about how primary producer diversity influences the efficiency of resource use and biomass production in ecosystems, how primary producer diversity influences the transfer and recycling of biomass to other trophic groups in a food web, and the number of species and spatial /temporal scales at which diversity effects are most apparent. After summarizing the balance of evidence and stating our own confidence in the conclusions, we outline several new questions that must now be addressed if this field is going to evolve into a predictive science that can help conserve and manage ecological processes in ecosystems.

Quantitative scenarios are coming of age as a tool for evaluating the impact of future socioeconomic development pathways on biodiversity and ecosystem services. We analyze global terrestrial, freshwater, and marine biodiversity scenarios using a range of measures including extinctions, changes in species abundance, habitat loss, and distribution shifts, as well as comparing model projections to observations. Scenarios consistently indicate that biodiversity will continue to decline over the 21st century. However, the range of projected changes is much broader than most studies suggest, partly because there are major opportunities to intervene through better policies, but also because of large uncertainties in projections.

Concern is growing about the consequences of biodiversity loss for ecosystem functioning, for the provision of ecosystem services, and for human well being. Experimental evidence for a relationship between biodiversity and ecosystem process rates is compelling, but the issue remains contentious. Here, we present the first rigorous quantitative assessment of this relationship through meta-analysis of experimental work spanning 50 years to June 2004. We analysed 446 measures of biodiversity effects (252 in grasslands), 319 of which involved primary producer manipulations or measurements. Our analyses show that: biodiversity effects are weaker if biodiversity manipulations are less well controlled; effects of biodiversity change on processes are weaker at the ecosystem compared with the community level and are negative at the population level; productivity-related effects decline with increasing number of trophic links between those elements manipulated and those measured; biodiversity effects on stability measures ('insurance' effects) are not stronger than biodiversity effects on performance measures. For those ecosystem services which could be assessed here, there is clear evidence that biodiversity has positive effects on most. Whilst such patterns should be further confirmed, a precautionary approach to biodiversity management would seem prudent in the meantime.

Knowledge about the biogeographic affinities of the world's tropical forests helps to better understand regional differences in forest structure, diversity, composition, and dynamics. Such understanding will enable anticipation of region-specific responses to global environmental change. Modern phylogenies, in combination with broad coverage of species inventory data, now allow for global biogeographic analyses that take species evolutionary distance into account. Here we present a classification of the world's tropical forests based on their phylogenetic similarity. We identify five principal floristic regions and their floristic relationships: (i) Indo-Pacific, (ii) Subtropical, (iii) African, (iv) American, and (v) Dry forests. Our results do not support the traditional neo- versus paleotropical forest division but instead separate the combined American and African forests from their Indo-Pacific counterparts. We also find indications for the existence of a global dry forest region, with representatives in America, Africa, Madagascar, and India. Additionally, a northern-hemisphere Subtropical forest region was identified with representatives in Asia and America, providing support for a link between Asian and American northern-hemisphere forests.

Relational values are values of desirable relationships between people and nature and among people (through nature). We report on the approach to capture relational values of nature's contributions to people in the regional assessment for Europe and Central Asia of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES). We present a framework considering indicators along four relational value dimensions about people's relationships with nature: security and sovereignty; health; equity and justice; and heritage, social identity and stewardship. The framework has been operationalized for three nature's contributions to people (NCP): regulation of freshwater quality and quantity, food and feed, and physical and psychological experiences derived from nature. We identify ways to empirically assess relational values of nature's contributions to people at regional and continental scales with social-ecological indicators and proxies, ranging from biophysical indicators to indicators that intersect socio-economic with biophysical data. We conclude that many of the identified indicators can be considered as useful proxies of relational values in a quantitative way. The analysis shows that relational values are essential to consider at the science-policy interface as they are an important set of values that people hold about nature and that go beyond instrumental relations. [ABSTRACT FROM AUTHOR]

Ecosystem services (ES) provide a range of benefits to people, but landowners that produce ES are often separate from those receiving benefits. As a result, landowners bear the costs of managing ecosystems, but often share the benefits with others. Accounting for these private and external costs and benefits would improve the effectiveness of payments for ES management.We develop a spatially explicit ES modelling approach to evaluate the alignment of private and external benefits resulting from habitat enhancement for pollinators. After testing the model on synthetic landscapes, we applied it to Yolo County, California, using information on crop type, value per acre and dependence on pollination. Detailed data on parcel ownership allowed us to distinguish private and external costs and benefits of enhancing habitat on any parcel.We found that around 13% of the landowners would generate private benefits that exceed private costs, 47% would generate external benefits greater than private costs, and the remaining 40% would generate neither private nor external benefits greater than private costs. Landowners generating private net benefits had larger fields, more valuable crops and more pollinator‐dependent crops than the other owners.These results reveal mis‐alignments between private and external incentives. Just over half of the Yolo County landowners' pollinator enhancements would produce external benefits, but only 25% of these would have private incentives to do so. We estimated that enhancements by those acting privately could increase the private net present value of crops by $495,309 and provide a total external benefit of $1,193,345. The remaining 47% of landowners' enhancements generated $1,409,247 in additional net external benefits.Accounting for heterogeneity in enhancement benefits due to ownership and crop characteristics allows one to distinguish contexts where enhancements should be managed by groups as a common‐pool resource or by individuals. Rather than fund a PES program to pay for enhancements, effort could be directed towards communicating with landowners about potential private benefits and facilitating common‐pool resource management. Overall, this analysis reveals the importance of partitioning private and external benefits of actions designed to provide ES. A free Plain Language Summary can be found within the Supporting Information of this article. A free Plain Language Summary can be found within the Supporting Information of this article. [ABSTRACT FROM AUTHOR]

Abstract: Ecosystem services science has developed at a fast rate in Latin America, a region characterized by a high biological and cultural diversity, strong emphasis in foreign investment, and high socioeconomic inequities. Here we conducted the following analyses at the regional and national scales: (1) how and when did the study of ecosystem services arise in each country?, (2) what is our present understanding of ecosystem service supply, delivery to societies, and social and economic values?, (3) what is the state of the art in integrating tradeoffs among services and in using interdisciplinary perspectives?, and (4) how has ecosystem service research been connected to policy design or management for sustainability? A large literature review (>1000 references) showed that in Latin America ES supply and links to policy have been the most frequently assessed. Overall, emphasis has been placed on a few services, namely carbon and water. Payments for ecosystem services have received considerable attention in the region, though with strong differences across nations and with important limitations in their application. The future of the ecosystem service paradigm in Latin America will largely depend on its capacity to demonstrate effectiveness in meeting both conservation and development goals. [Copyright &y& Elsevier]

Earth's life-support systems are in flux, yet no centralized system to monitor and report these changes exists. Recognizing this, 77 nations agreed to establish the Group on Earth Observations (GEO). The GEO Biodiversity Observation Network (GEO BON) integrates existing data streams into one platform in order to provide a more complete picture of Earth's biological and social systems. We present a conceptual framework envisioned by the GEO BON Ecosystem Services Working Group, designed to integrate national statistics, numerical models, remote sensing, and in situ measurements to regularly track changes in ecosystem services across the globe. This information will serve diverse applications, including stimulating new research and providing the basis for assessments. Although many ecosystem services are not currently measured, others are ripe for reporting. We propose a framework that will continue to grow and inspire more complete observation and assessments of our planet's life-support systems. [ABSTRACT FROM AUTHOR]

Copyright of Biotropica 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.)

The article discusses that according to Global Assessment Report by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services, millions of species are threatened with extinction due to carbon footprints and many benefits that the humans get from the nature have declined since last five decades and will continue till at least 2050.

This metadata set contains 761 effects of biodiversity on ecosystem, community, or population response variables reported in 137 publications from 1974 to June 2004. All data were obtained in experimental studies. Relationships between species richness or other biodiversity measures and response variables are described by their shape, direction, significance, and if available, the simple (regression) or multiple (analysis of variance) correlation coefficient. We classified response variables into groups according to the ecosystem function or service to which they were related, the trophic level at which they were measured, and several other classification schemes. Similarly, we classified studies into groups according to ecosystem type, experimental system (bottle/pot, greenhouse, field), range and trophic level of biodiversity treatments, and further design variables. Covariates include location of study, number of plots, and number of species used in the biodiversity treatments. Analyses of these metadata have shown, for example, that biodiversity effects on community (and ecosystem) variables are often positive, and those on population variables negative, that stocks are more responsive than rates to biodiversity manipulation, and that bottom-up biodiversity effects in multi-trophic studies are often negative. This metadata set gives a representative overview of the results of a first generation of biodiversity experiments and allows a quantitative assessment of the influence of a number of biological and design variables on the significance and shape of the relationship between biodiversity and response variables. [ABSTRACT FROM AUTHOR]

Editorial. Examines whether different objectives for conservation conflict with or reinforce each other. Biodiversity conservation for its own sake; Safeguarding of ecosystem services for humanity's sake; Goals of the Millennium Ecosystem Assessment.

The article examines the post-2020 global biodiversity framework by the United Nations Convention on Biological Diversity and ways for it to support transformative change in food systems. It discusses the causes of biodiversity loss, targets and indicators for sustainable food production and consumption, and barriers and opportunities for implementation in Great Britain and Peru.

Stakeholder groups are not homogeneous across individuals and through time, especially in relation to the importance of ecosystem services. However, the approaches commonly used to characterize the average importance and values of stakeholder groups overlook the heterogeneity in the individual priorities. This heterogeneity is particularly relevant for smallholders, who play a key role in ecosystem management but are more vulnerable to globalization than owners of large plots. We analyzed the priorities differentially assigned to ecosystem services and the reasons associated with the importance attributed to those services by individual cattle ranchers on the Pacific Coast of Mexico. We interviewed 27 cattle ranchers from neighboring rural communities. The services perceived by each rancher were identified from selected regional photographs. These services were then arranged in order of importance by interviewees, who were asked to provide the reasons for their choices. We used multivariate methods to examine the relationship between priorities for services and the livelihood of the individual. Interpretative qualitative methods elicited the reasons associated with the relative importance of the prioritized services. We identified 54 different services. Overall, individuals prioritized provisioning services directly related to their ranching activity. Individuals with the highest level of education and greatest diversity of productive activities (e.g., farmer, mason, merchant) also prioritized cultural services associated with ecotourism potential. The reasons associated with the importance attributed to the prioritized services varied widely among individuals. The list of ecosystem services perceived was context-specific, strongly influenced by the salient characteristics of the ecosystem and of the ranching way of life. A generational change in livelihoods has affected priorities. The reasons behind the importance of the prioritized services were diverse among individuals. By revealing the heterogeneity among individuals, we emphasize the need to make flexible policies that integrate diverse values and contexts to accomplish smallholder inclusivity. [ABSTRACT FROM AUTHOR]

Human beings manage ecosystems to obtain ecosystem services. Through selected interventions they modify ecosystem condition to increase the provisioning services of interest to people. We analyzed the effect of livestock management regime components (duration, grazing period, number of burns and slashes and stocking density) on ecosystem services (provisioning, regulating and supporting) in seeded pastures in a tropical dry region. Our main questions were: (1) How is livestock management duration related to the magnitude of service supply?; (2) How are the different components of the livestock management regime and site conditions related to the magnitude of ecosystem service supply?; and (3) How do the components of management regime, the site conditions and the magnitude of ecosystem service supply interact? We quantified 15 service indicators within 24 plots (20 × 50 m) chosen along a 40-year gradient of livestock management duration. Livestock management regime was documented with semi-structured interviews to landowners. Simple linear regressions showed that increasing livestock management duration was related to increasing forage amount ( p = 0.03) and to decreasing forage quality ( p = 0.05), soil structure ( p = 0.002), and several biodiversity indicators ( p = 0.002-0.03). Stepwise multiple regression analyses showed that the increase in the total number of burns was related to decreases in foliar and soil nitrogen ( p < 0.05), carbon stock ( p < 0.001), as well as woody, herbaceous, and seedling richness or evenness ( p < 0.001). Increased frequency of slashes and of the grazing period also decreased soil fertility regulation and biodiversity. The canonical correspondence analysis showed a prominent role of the number of burns (which is correlated with duration, slashing frequency and grazing period) in promoting forage production, but in reducing most indicators of regulating and supporting services. Increased shallow soil moisture was related to increasing regulating and supporting services. Canopy covers inside the plot and in the surrounding forest were positively related to woody and seedling richness or evenness, but were independent of the effects of other management regime components. Our study suggests a conflict between the short-term management decisions such as burning to foster forage production and the long term sustainability of the management regime of these seeded pastures. [ABSTRACT FROM AUTHOR]