Assessing nature's contributions to people Díaz, Sandra; Pascual, Unai; Stenseke, Marie ...
Science (American Association for the Advancement of Science),
01/2018, Letnik:
359, Številka:
6373
Journal Article
Recenzirano
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Recognizing culture, and diverse sources of knowledge, can improve assessments
A major challenge today and into the future is to maintain or enhance beneficial contributions of nature to a good ...quality of life for all people. This is among the key motivations of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), a joint global effort by governments, academia, and civil society to assess and promote knowledge of Earth's biodiversity and ecosystems and their contribution to human societies in order to inform policy formulation. One of the more recent key elements of the IPBES conceptual framework (
1
) is the notion of nature's contributions to people (NCP), which builds on the ecosystem service concept popularized by the Millennium Ecosystem Assessment (MA) (
2
). But as we detail below, NCP as defined and put into practice in IPBES differs from earlier work in several important ways. First, the NCP approach recognizes the central and pervasive role that culture plays in defining all links between people and nature. Second, use of NCP elevates, emphasizes, and operationalizes the role of indigenous and local knowledge in understanding nature's contribution to people.
We reviewed responses of nitrification, denitrification, and soil N2O efflux to elevated CO2, N availability, and temperature, based on published experimental results. We used meta‐analysis to ...estimate the magnitude of response of soil N2O emissions, nitrifying enzyme activity (NEA), denitrifying enzyme activity (DEA), and net and gross nitrification across experiments. We found no significant overall effect of elevated CO2 on N2O fluxes. DEA and NEA significantly decreased at elevated CO2; however, gross nitrification was not modified by elevated CO2, and net nitrification increased. The negative overall response of DEA to elevated CO2 was associated with decreased soil NO3−, suggesting that reduced availability of electron acceptors may dominate the responses of denitrification to elevated CO2. N addition significantly increased field and laboratory N2O emissions, together with gross and net nitrification, but the effect of N addition on field N2O efflux was not correlated to the amount of N added. The effects of elevated temperature on DEA, NEA, and net nitrification were not significant: The small number of studies available stress the need for more warming experiments in the field. While N addition had large effects on measurements of nitrification and denitrification, the effects of elevated CO2 were less pronounced and more variable, suggesting that increased N deposition is likely to affect belowground N cycling with a magnitude of change that is much larger than that caused by elevated CO2.
In 2010, the international community, under the auspices of the Convention on Biological Diversity, agreed on 20 biodiversity-related “Aichi Targets” to be achieved within a decade. We provide a ...comprehensive mid-term assessment of progress toward these global targets using 55 indicator data sets. We projected indicator trends to 2020 using an adaptive statistical framework that incorporated the specific properties of individual time series. On current trajectories, results suggest that despite accelerating policy and management responses to the biodiversity crisis, the impacts of these efforts are unlikely to be reflected in improved trends in the state of biodiversity by 2020. We highlight areas of societal endeavor requiring additional efforts to achieve the Aichi Targets, and provide a baseline against which to assess future progress.
Scenarios for Global Biodiversity in the 21st Century Pereira, Henrique M.; Leadley, Paul W.; Proença, Vânia ...
Science (American Association for the Advancement of Science),
12/2010, Letnik:
330, Številka:
6010
Journal Article
Recenzirano
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.
Global environmental changes are expected to alter ecosystem carbon and nitrogen cycling, but the interactive effects of multiple simultaneous environmental changes are poorly understood. Effects of ...these changes on the production of nitrous oxide (N2O), an important greenhouse gas, could accelerate climate change. We assessed the responses of soil N2O fluxes to elevated CO2, heat, altered precipitation, and enhanced nitrogen deposition, as well as their interactions, in an annual grassland at the Jasper Ridge Global Change Experiment (CA, USA). Measurements were conducted after 6, 7 and 8 years of treatments. Elevated precipitation increased N2O efflux, especially in combination with added nitrogen and heat. Path analysis supported the idea that increased denitrification due to increased soil water content and higher labile carbon availability best explained increased N2O efflux, with a smaller, indirect contribution from nitrification. In our data and across the literature, single-factor responses tended to overestimate interactive responses, except when global change was combined with disturbance by fire, in which case interactive effects were large. Thus, for chronic global environmental changes, higher order interactions dampened responses of N2O efflux to multiple global environmental changes, but interactions were strongly positive when global change was combined with disturbance. Testing whether these responses are general should be a high priority for future research.
Little is known about the combined impacts of global environmental changes and ecological disturbances on ecosystem functioning, even though such combined impacts might play critical roles in shaping ...ecosystem processes that can in turn feed back to climate change, such as soil emissions of greenhouse gases.
We took advantage of an accidental, low-severity wildfire that burned part of a long-term global change experiment to investigate the interactive effects of a fire disturbance and increases in CO(2) concentration, precipitation and nitrogen supply on soil nitrous oxide (N(2)O) emissions in a grassland ecosystem. We examined the responses of soil N(2)O emissions, as well as the responses of the two main microbial processes contributing to soil N(2)O production--nitrification and denitrification--and of their main drivers. We show that the fire disturbance greatly increased soil N(2)O emissions over a three-year period, and that elevated CO(2) and enhanced nitrogen supply amplified fire effects on soil N(2)O emissions: emissions increased by a factor of two with fire alone and by a factor of six under the combined influence of fire, elevated CO(2) and nitrogen. We also provide evidence that this response was caused by increased microbial denitrification, resulting from increased soil moisture and soil carbon and nitrogen availability in the burned and fertilized plots.
Our results indicate that the combined effects of fire and global environmental changes can exceed their effects in isolation, thereby creating unexpected feedbacks to soil greenhouse gas emissions. These findings highlight the need to further explore the impacts of ecological disturbances on ecosystem functioning in the context of global change if we wish to be able to model future soil greenhouse gas emissions with greater confidence.
Soil and nutrient properties, via their influence on nutrient diffusion rates in the soil, may play a key role in determining the outcome of plant competition for nutrients. We used two models to ...explore the potential contributions of nutrient uptake kinetics, root density, soil properties, and nutrient type to interspecific plant competition for soil nutrients. The first model uses well-known nutrient diffusion and absorption relationships to generate soil nutrient concentration maps and nutrient uptake at the scale of individual roots (PARIS-M). A second model (PARIS-E) was developed based on a fit of the Hill equation to the output of PARIS-M. The PARIS-E model provides an accurate and simple means of determining the relative contributions of sink strength (root surface area x uptake kinetics) vs. space occupation (number of roots per unit area) to competition at equilibrium as modeled by PARIS-M. An analysis based on these two models suggests the following: (1)Diffusive supply (soil nutrient buffer capacity x effective diffusion coefficient) determines the relative importance of space occupation vs. sink strength for nutrient competition. (2) At the low range of reported values of diffusive supply, competition depends on space occupation and, therefore, the species with the most roots per unit area is the most competitive. Sink strength gains in importance as diffusive supply increases and dominates competitive interactions at the high end of the range of reported diffusive supplies. (3) The relative importance of space occupation vs. sink strength depends primarily on soil water content and soil texture, because diffusive supply is sensitive to these factors. Diffusive supply is relatively insensitive to nutrient type. This analysis suggests that nutrient competition models should include the effects of soil properties as a determinant of the relative contributions of sink strength vs. space occupation.
In 2010, the parties of the Convention on Biological Diversity (CBD) adopted the Strategic Plan for Biodiversity 2011–2020 with the mission of halting biodiversity loss and enhance the benefits it ...provides to people. The 20 Aichi Biodiversity Targets (Aichi Targets), which are included in the Strategic Plan, are organized under five Strategic Goals, and provide coherent guidance on how to achieve it. Halfway through the Strategic Plan, it is time to prioritize actions in order to achieve the best possible outcomes for the Aichi Targets in 2020. Actions to achieve one target may influence other targets (downstream interactions); in turn a target may be influenced by actions taken to attain other targets (upstream interactions). We explore the interactions among targets and the time-lags between implemented measures and desired outcomes to develop a framework that can reduce the overall burden associated with the implementation of the Strategic Plan. We identified the targets addressing the underlying drivers of biodiversity loss and the targets aimed at enhancing the implementation of the Strategic Plan as having the highest level of downstream interactions. Targets aimed at improving the status of biodiversity and safeguarding ecosystems followed by targets aimed at reducing the direct pressures on biodiversity and enhancing the benefits to all from biodiversity and ecosystem services, were identified as having the highest levels of upstream interactions. Perhaps one of the most challenging aspects of the Strategic Plan is the need to balance actions for its long-term sustainability with the need for urgent actions to halt biodiversity loss.
Im Jahre 2010 fasste die Biodiversitäts-Konvention einen Beschluss zum Schutz der Biodiversität für die Dekade 2011–2020. Das primäre Ziel dieses Strategischen Plans ist es, den Verlust von Biodiversität zu reduzieren, sowie ihre enorme Bedeutung für die Menschen zu veranschaulichen. In diesen Strategischen Plan sind die “20 Aichi – Ziele” integriert, die in fünf Kernziele kategorisiert sind und als Leitfaden zur Realisierung der Aichi-Ziele dienen. Im Rahmen des Strategieplans ist es an der Zeit die Maßnahmen zu priorisieren, welche maximale Erfolge zum Erreichen der “20 Aichi–Ziele” bis 2020 versprechen. Dabei muss betrachtet werden, dass bestimmte Maßnahmen zur Zielführung möglicherweise andere Ziele beeinflussen (s.g. abwärts gerichtete Interaktionen=“downstream interactions”); im Gegensatz dazu können Ziele wiederum die Maßnahmen beeinflussen (s.g. aufwärts gerichtete Interaktionen=“upstream interactions”).
Wir untersuchten die Wechselwirkungen zwischen den Kernzielen und den Zeitintervallen, zwischen den durchgeführten Maßnahmen und dem Eintreten der gewünschten Ergebnisse. Diese Untersuchungen sind notwendig, um die wichtigsten Maßnahmen mit den höchsten Effekten innerhalb aller Ziele zu identifizieren. Dabei identifizierten wir Ziele, welche sich primär mit den Ursachen des Rückgangs biologischer Vielfalt beschäftigen und Ziele, in deren Fokus die Verfolgung des Strategischen Plans steht, als hochgradig abwärts gerichtete Interaktionen. Ziele, die sich vornehmlich mit der Sicherung von Ökosystemen zur Verbesserung der biologischen Vielfalt beschäftigen, gefolgt von denen, deren Schwerpunkt auf der Reduktion von direkten Belastungen auf biologische Vielfalt liegt, und jene, die aufzeigen, welchen Mehrwert biologische Vielfalt und Ökosystemleistungen für alle bieten, weisen die höchsten aufwärts gerichteten Interaktionen auf. Einer der schwierigsten Aspekte bei der Umsetzung des strategischen Plans ist die Notwendigkeit einer Balance zwischen Maßnahmen zur Umsetzung einer langfristigen Nachhaltigkeit und der Umsetzung von notwendigen kurzfristigen Sofortmaßnahmen zu finden, welche den Verlust der biologischen Vielfalt aufhalten.
Despite increasing interest in the effects of climate change on soil processes, the response of nitrification to elevated CO₂ remains unclear. Responses may depend on soil nitrogen (N) status, and ...inferences may vary depending on the methodological approach used. We investigated the interactive effects of elevated CO₂ and inorganic N supply on gross nitrification (using ¹⁵N pool dilution) and potential nitrification (using nitrifying enzyme activity assays) in Dactylis glomerata mesocosms. We measured the responses of putative drivers of nitrification (NH ₄ ⁺ production, NH ₄ ⁺ consumption, and soil environmental conditions) and of potential denitrification, a process functionally linked to nitrification. Gross nitrification was insensitive to all treatments, whereas potential nitrification was higher in the high N treatment and was further stimulated by elevated CO₂ in the high N treatment. Gross mineralization and NH ₄ ⁺ consumption rates were also significantly increased in response to elevated CO₂ in the high N treatment, while potential denitrification showed a significant increase in response to N addition. The discrepancy between the responses of gross and potential nitrification to elevated CO₂ and inorganic N supply suggest that these measurements provide different information, and should be used as complementary approaches to understand nitrification response to global change.
Aim To analyse global patterns of climate during the mid-Holocene and conduct comparisons with pre-industrial and projected future climates. In particular, to assess the exposure of terrestrial ...biomes and ecoregions to climate-related risks during the Holocene–Anthropocene transition starting at the pre-industrial period. Location Terrestrial ecosystems of the Earth. Methods We calculated long-term climate differences (anomalies) between the mid-Holocene (6 ka cal BP, mH), pre-industrial conditions and projections for 2100 (middle-strength A1B scenario) using six global circulation models available for all periods. Climate differences were synthesized with multivariate statistics and average principal component loadings of temperature and precipitation differences (an estimate of climate-related risks) were calculated on 14 biomes and 766 ecoregions. Results Our results suggest that most of the Earth's biomes will probably undergo changes beyond the mH recorded levels of community turnover and range shifts because the magnitude of climate anomalies expected in the future are greater than observed during the mH. A few biomes, like the remnants of North American and Euro-Asian prairies, may experience only slightly greater degrees of climate change in the future as compared with the mH. In addition to recent studies that have identified equatorial regions as the most sensitive to future climate change, we find that boreal forest, tundra and vegetation of the Equatorial Andes could be at greatest risk, since these regions will be exposed to future climates that are well outside natural climate variation during the Holocene. Conclusions The Holocene–Anthropocene climate transition, even for a middle-strength future climate change scenario, appears to be of greater magnitude and different from that between the mH and the pre-industrial period. As a consequence, community- and biome-level changes due to of expected climate change may be different in the future from those observed during the mH.
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