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尹彩春  赵文武 《生态学报》2021,41(23):9536-9542
2021年2月18日,联合国环境署发布《与自然和谐共处:应对气候、生物多样性和污染危机的科学蓝图》。报告指出:气候变化、生物多样性下降和环境污染已经成为全球三大环境紧急情况;人与自然关系面临着社会经济发展压力加剧环境风险、遏制环境恶化的全球承诺尚未兑现、环境风险威胁可持续发展目标等多重挑战;全球亟需开展以联合国可持续发展目标为框架的系统变革,加快应对全球环境危机的重点行动,改革资源环境和经济系统,提高粮食、能源和水系统的环境友好性与可持续性,加强对人体健康与生态环境健康的协同保护,进而推动人与自然的和谐共处以及可持续发展。该报告结合全球环境评估的最新进展,强调了社会-经济-环境可持续发展仍是未来的重要研究课题,对我国社会-生态系统与可持续发展等领域的科学研究有如下启示:(1)创新社会-生态系统的综合集成研究,探寻不同发展路径和气候变化情景下社会-生态系统时空演变特征与趋势;(2)注重科学研究对决策的支撑以及与国际重大议程的衔接,探索和创新可持续发展的中国方案。  相似文献   

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Determining how thermal variability will affect the structure, stability, and function of ecological communities is becoming increasingly important as global warming is predicted to affect not only average temperatures but also increase the frequency of long runs of high temperatures. Latitudinal differences in the responses of ecological communities to changes in their thermal regimes have also been predicted based on adaptations over evolutionary time to different thermal environments. We conducted an experiment to determine whether variability in temperature leads to consistent changes in community structure, temporal dynamics, and ecosystem functioning in laboratory analogues of natural freshwater supralittoral rock pool communities inhabited by meiofauna and zooplankton collected from sub‐Arctic, temperate, and tropical regions. Thermal variability of +4 °C around mean temperature led to increased extinction frequency, decreases in consumer abundance, increases in temporal variability of consumer abundance, and shifts from predominately negative interactions observed under constant temperature to positive interactions in the temperate and tropical communities but not in the sub‐Arctic communities. That sub‐Arctic zooplankton communities may be more robust to thermal variability than temperate or tropical communities’ supports recent studies on macrophysiological adaptations of species along latitudinal gradients and suggests that increasing thermal variability may have the greatest effects on community structure and function in tropical and temperate regions.  相似文献   

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Driven by climate change, marine biodiversity is undergoing a phase of rapid change that has proven to be even faster than changes observed in terrestrial ecosystems. Understanding how these changes in species composition will affect future marine life is crucial for conservation management, especially due to increasing demands for marine natural resources. Here, we analyse predictions of a multiparameter habitat suitability model covering the global projected ranges of >33,500 marine species from climate model projections under three CO2 emission scenarios (RCP2.6, RCP4.5, RCP8.5) up to the year 2100. Our results show that the core habitat area will decline for many species, resulting in a net loss of 50% of the core habitat area for almost half of all marine species in 2100 under the high-emission scenario RCP8.5. As an additional consequence of the continuing distributional reorganization of marine life, gaps around the equator will appear for 8% (RCP2.6), 24% (RCP4.5), and 88% (RCP8.5) of marine species with cross-equatorial ranges. For many more species, continuous distributional ranges will be disrupted, thus reducing effective population size. In addition, high invasion rates in higher latitudes and polar regions will lead to substantial changes in the ecosystem and food web structure, particularly regarding the introduction of new predators. Overall, our study highlights that the degree of spatial and structural reorganization of marine life with ensued consequences for ecosystem functionality and conservation efforts will critically depend on the realized greenhouse gas emission pathway.  相似文献   

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Understanding biodiversity changes in the Anthropocene (e.g. due to climate and land‐use change) is an urgent ecological issue. This important task is challenging because global change effects and species responses are dependent on the spatial scales considered. Furthermore, responses are often not immediate. However, both scale and time delay issues can be tackled when, at each study site, we consider dynamics in both observed and dark diversity. Dark diversity includes those species in the region that can potentially establish and thrive in the local sites’ conditions but are currently locally absent. Effectively, dark diversity connects biodiversity at the study site to the regional scales and defines the site‐specific species pool (observed and dark diversity together). With dark diversity, it is possible to decompose species gains and losses into two space‐related components: one associated with local dynamics (species moving from observed to dark diversity and vice versa) and another related to gains and losses of site‐specific species pool (species moving to and from the pool after regional immigration, regional extinction or change in local ecological conditions). Extinction debt and immigration credit are useful to understand dynamics in observed diversity, but delays might happen in species pool changes as well. In this opinion piece we suggest that considering both observed and dark diversity and their temporal dynamics provides a deeper understanding of biodiversity changes. Considering both observed and dark diversity creates opportunities to improve conservation by allowing to identify species that are likely to go regionally extinct as well as foreseeing which of the species that newly arrive to the region are more likely to colonize local sites. Finally, by considering temporal lags and species gains and losses in observed and dark diversity, we combine phenomena at both spatial and temporal scales, providing a novel tool to examine biodiversity change in the Anthropocene.  相似文献   

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  总被引:7,自引:2,他引:7  
Current knowledge of effects of climate change on biodiversity is briefly reviewed, and results are presented of a survey of biological research groups in the Netherlands, aimed at identifying key research issues in this field. In many areas of the world, biodiversity is being reduced by humankind through changes in land cover and use, pollution, invasions of exotic species and possibly climate change. Assessing the impact of climate change on biodiversity is difficult, because changes occur slowly and effects of climate change interact with other stress factors already imposed on the environment. Research issues identified by Dutch scientists can be grouped into: (i) spatial and temporal distributions of taxa; (ii) migration and dispersal potentials of taxa; (iii) genetic diversity and viability of (meta) populations of species; (iv) physiological tolerance of species; (v) disturbance of functional interactions between species; and (vi) ecosystem processes. Additional research should be done on direct effects of greenhouse gases, and on interactions between effects of climate change and habitat fragmentation. There are still many gaps in our knowledge of effects of climate change on biodiversity. An interdisciplinary research programme could possibly focus only on one or few of the identified research issues, and should generate input data for predictive models based on climate change scenarios.  相似文献   

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《生物多样性公约》下的气候变化问题:谈判与焦点   总被引:1,自引:0,他引:1  
近年来,生物多样性与气候变化的关系逐渐成为《生物多样性公约》下的焦点议题,各缔约方就此问题展开了激烈的多边谈判.本文梳理了《生物多样性公约》下气候变化问题谈判的发展历程,探讨了其中的焦点问题及各方的主要立场,指出以欧盟为代表的发达国家和以巴西、哥伦比亚、中国为代表的发展中生物多样性大国是针锋相对的两大主要谈判集团.谈判...  相似文献   

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The global scale and rapidity of environmental change is challenging ecologists to reimagine their theoretical principles and management practices. Increasingly, historical ecological conditions are inadequate targets for restoration ecology, geographically circumscribed nature reserves are incapable of protecting all biodiversity, and the precautionary principle applied to management interventions no longer ensures avoidance of ecological harm. In addition, human responses to global environmental changes, such as migration, building of protective infrastructures, and land use change, are having their own negative environmental impacts. We use examples from wildlands, urban, and degraded environments, as well as marine and freshwater ecosystems, to show that human adaptation responses to rapid ecological change can be explicitly designed to benefit biodiversity. This approach, which we call “renewal ecology,” is based on acceptance that environmental change will have transformative effects on coupled human and natural systems and recognizes the need to harmonize biodiversity with human infrastructure, for the benefit of both.  相似文献   

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Social media plays an outsized role in information dissemination, issue mobilization, and public influence. For environmental nongovernmental organizations (“eNGOs”), social media plays a critical role in fundraising and inspiring engaged audiences using rich media and punchy taglines. Yet, there is little to no accounting of whether and how eNGOs have adopted social media, limiting analyses of how eNGOs are leveraging social media to develop effective communication strategies and campaigns. We analyzed the social media presence of over 100 eNGOs. We evaluated which platforms are used by eNGOs and differences between them in terms of their visibility on social media. 88%–97% of the eNGOs in our sample use four out of the five leading social media platforms. There were marked differences across eNGOs and platforms in terms of public visibility, represented by the number of followers. eNGOs focusing on advocacy, aquatic environments, and species conservation had significantly larger numbers of followers. Our findings indicate that conservation can make more headway on newer, more visually-oriented platforms that also have stronger youth traction. We use our analyses to identify which eNGOs have much larger followings on social media than expected. These leaders can provide lessons on how eNGOs can enhance their social media impact.  相似文献   

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Coastal upwelling regions, which are affected by equatorward‐wind variability, are among the most productive areas of the oceans. It has been suggested that global warming will lead to a general strengthening of coastal upwelling, with important ecological implications and an impact on fisheries. However, in the case of the Iberian upwelling, the long‐term analysis of climatological variables described here reveals a weakening in coastal upwelling. This is linked to a decrease of zonal sea level pressure gradient, and correlated with an observed increase of sea surface temperature and North Atlantic Oscillation. Weakening of coastal upwelling has led to quantifiable modifications of the ecosystem. In outer shelf waters a drop in new production over the last 40 years is likely related to the reduction of sardine landings at local harbors. On the other hand, in inner shelf and Ria waters, the observed weakening of upwelling has slowed down the residual circulation that introduces nutrients to the euphotic layer, and has increased the stability of the water column. The drop in nutrient levels has been compensated by an increase of organic matter remineralization. The phytoplankton community has responded to those environmental trends with an increase in the percentage of dinoflagellates and Pseudonitzschia spp. and a reduction in total diatoms. The former favors the proliferation of harmful algal blooms and reduces the permitted harvesting period for the mussel aquaculture industry. The demise of the sardine fishery and the potential threat to the mussel culture could have serious socio‐economic consequences for the region.  相似文献   

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Difficulty in characterizing the relationship between climatic variability and climate change vulnerability arises when we consider the multiple scales at which this variation occurs, be it temporal (from minute to annual) or spatial (from centimetres to kilometres). We studied populations of a single widely distributed butterfly species, Chlosyne lacinia, to examine the physiological, morphological, thermoregulatory and biophysical underpinnings of adaptation to tropical and temperate climates. Microclimatic and morphological data along with a biophysical model documented the importance of solar radiation in predicting butterfly body temperature. We also integrated the biophysics with a physiologically based insect fitness model to quantify the influence of solar radiation, morphology and behaviour on warming impact projections. While warming is projected to have some detrimental impacts on tropical ectotherms, fitness impacts in this study are not as negative as models that assume body and air temperature equivalence would suggest. We additionally show that behavioural thermoregulation can diminish direct warming impacts, though indirect thermoregulatory consequences could further complicate predictions. With these results, at multiple spatial and temporal scales, we show the importance of biophysics and behaviour for studying biodiversity consequences of global climate change, and stress that tropical climate change impacts are likely to be context-dependent.  相似文献   

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The catastrophic loss of large-bodied mammals during the terminal Pleistocene likely led to cascading effects within communities. While the extinction of the top consumers probably expanded the resources available to survivors of all body sizes, little work has focused on the responses of the smallest mammals. Here, we use a detailed fossil record from the southwestern United States to examine the response of the hispid cotton rat Sigmodon hispidus to biodiversity loss and climatic change over the late Quaternary. In particular, we focus on changes in diet and body size. We characterize diet through carbon (δ13C) and nitrogen (δ15N) isotope analysis of bone collagen in fossil jaws and body size through measurement of fossil teeth; the abundance of material allows us to examine population level responses at millennial scale for the past 16 ka. Sigmodon was not present at the cave during the full glacial, first appearing at ~16 ka after ice sheets were in retreat. It remained relatively rare until ~12 ka when warming temperatures allowed it to expand its species range northward. We find variation in both diet and body size of Sigmodon hispidus over time: the average body size of the population varied by ~20% (90–110 g) and mean δ13C and δ15N values ranged between −13.5 to −16.5‰ and 5.5 to 7.4‰ respectively. A state–space model suggested changes in mass were influenced by diet, maximum temperature and community structure, while the modest changes in diet were most influenced by community structure. Sigmodon maintained a fairly similar dietary niche over time despite contemporaneous changes in climate and herbivore community composition that followed the megafauna extinction. Broadly, our results suggest that small mammals may be as sensitive to shifts in local biotic interactions within their ecosystem as they are to changes in climate and large-scale biodiversity loss.  相似文献   

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The coastal ecosystems of temperate North America provide a variety of ecosystem services including high rates of carbon sequestration. Yet, little data exist for the carbon stocks of major tidal wetland types in the Pacific Northwest, United States. We quantified the total ecosystem carbon stocks (TECS) in seagrass, emergent marshes, and forested tidal wetlands, occurring along increasing elevation and decreasing salinity gradients. The TECS included the total aboveground carbon stocks and the entire soil profile (to as deep as 3 m). TECS significantly increased along the elevation and salinity gradients: 217 ± 60 Mg C/ha for seagrass (low elevation/high salinity), 417 ± 70 Mg C/ha for low marsh, 551 ± 47 Mg C/ha for high marsh, and 1,064 ± 38 Mg C/ha for tidal forest (high elevation/low salinity). Soil carbon stocks accounted for >98% of TECS in the seagrass and marsh communities and 78% in the tidal forest. Soils in the 0–100 cm portion of the profile accounted for only 48%–53% of the TECS in seagrasses and marshes and 34% of the TECS in tidal forests. Thus, the commonly applied limit defining TECS to a 100 cm depth would greatly underestimate both carbon stocks and potential greenhouse gas emissions from land‐use conversion. The large carbon stocks coupled with other ecosystem services suggest value in the conservation and restoration of temperate zone tidal wetlands through climate change mitigation strategies. However, the findings suggest that long‐term sea‐level rise effects such as tidal inundation and increased porewater salinity will likely decrease ecosystem carbon stocks in the absence of upslope wetland migration buffer zones.  相似文献   

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Time series of environmental measurements are essential for detecting, measuring and understanding changes in the Earth system and its biological communities. Observational series have accumulated over the past 2–5 decades from measurements across the world's estuaries, bays, lagoons, inland seas and shelf waters influenced by runoff. We synthesize information contained in these time series to develop a global view of changes occurring in marine systems influenced by connectivity to land. Our review is organized around four themes: (i) human activities as drivers of change; (ii) variability of the climate system as a driver of change; (iii) successes, disappointments and challenges of managing change at the sea‐land interface; and (iv) discoveries made from observations over time. Multidecadal time series reveal that many of the world's estuarine–coastal ecosystems are in a continuing state of change, and the pace of change is faster than we could have imagined a decade ago. Some have been transformed into novel ecosystems with habitats, biogeochemistry and biological communities outside the natural range of variability. Change takes many forms including linear and nonlinear trends, abrupt state changes and oscillations. The challenge of managing change is daunting in the coastal zone where diverse human pressures are concentrated and intersect with different responses to climate variability over land and over ocean basins. The pace of change in estuarine–coastal ecosystems will likely accelerate as the human population and economies continue to grow and as global climate change accelerates. Wise stewardship of the resources upon which we depend is critically dependent upon a continuing flow of information from observations to measure, understand and anticipate future changes along the world's coastlines.  相似文献   

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Bird species richness is mediated by local, regional, and historical factors, for example, competition, environmental heterogeneity, contemporary, and historical climate. Here, we related bird species richness with phylogenetic relatedness of bird assemblages, plant species richness, topography, contemporary climate, and glacial‐interglacial climate change to investigate the relative importance of these factors. This study was conducted in Inner Mongolia, an arid and semiarid region with diverse vegetation types and strong species richness gradients. The following associated variables were included as follows: phylogenetic relatedness of bird assemblages (Net Relatedness Index, NRI), plant species richness, altitudinal range, contemporary climate (mean annual temperature and precipitation, MAT and MAP), and contemporary‐Last Glacial Maximum (LGM) change in climate (change in MAT and change in MAP). Ordinary least squares linear, simultaneous autoregressive linear, and Random Forest models were used to assess the associations between these variables and bird species richness across this region. We found that bird species richness was correlated negatively with NRI and positively with plant species richness and altitudinal range, with no significant correlations with contemporary climate and glacial–interglacial climate change. The six best combinations of variables ranked by Random Forest models consistently included NRI, plant species richness, and contemporary‐LGM change in MAT. Our results suggest important roles of local ecological factors in shaping the distribution of bird species richness across this semiarid region. Our findings highlight the potential importance of these local ecological factors, for example, environmental heterogeneity, habitat filtering, and biotic interactions, in biodiversity maintenance.  相似文献   

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Coastal groundwater-dependent ecosystems (GDEs), such as wetlands, estuaries and mangrove forests, are globally important habitats that promote biodiversity, provide climate regulation and serve as refugia for plant and animal communities. However, global warming, coastal development and over-abstraction threaten the availability and quality of groundwater in coastal aquifers and, by extension, the ecohydrological function of dependent ecosystems. Because ecohydrological knowledge of coastal groundwater is disparate across disciplines and habitat types, we begin by summarising the physiochemical, biological and hydrological processes supported by groundwater across coastal watersheds. Groundwater makes a significant but poorly recognised contribution to the function and resilience of coastal ecosystems and will play an essential role in climate change mitigation and adaptation. This review then explores how critical ecosystem processes supported by groundwater will be affected in areas of the humid subtropics that are expected to be impacted by climatic drying. Where rainfall is predicted to decrease, reduced groundwater recharge will interrupt the hydrology of coastal GDEs, while anthropogenic pressures, such as land-use intensification and pollution, will diminish the quality of remaining groundwater. The challenges of managing groundwater for multiple purposes under climate change predictions are highlighted. To improve the management of coastal GDEs, research should be aimed at developing robust conceptual models of coastal groundwater systems that quantify biophysical linkages with ecological communities across relevant spatiotemporal scales.  相似文献   

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Sea level rise (SLR) threatens coastal wetlands worldwide, yet the fate of individual wetlands will vary based on local topography, wetland morphology, sediment dynamics, hydrologic processes, and plant‐mediated feedbacks. Local variability in these factors makes it difficult to predict SLR effects across wetlands or to develop a holistic regional perspective on SLR response for a diversity of wetland types. To improve regional predictions of SLR impacts to coastal wetlands, we developed a model that addresses the scale‐dependent factors controlling SLR response and accommodates different levels of data availability. The model quantifies SLR‐driven habitat conversion within wetlands across a region by predicting changes in individual wetland hypsometry. This standardized approach can be applied to all wetlands in a region regardless of data availability, making it ideal for modeling SLR response across a range of scales. Our model was applied to 105 wetlands in southern California that spanned a broad range of typology and data availability. Our findings suggest that if wetlands are confined to their current extents, the region will lose 12% of marsh habitats (vegetated marsh and unvegetated flats) with 0.6 m of SLR (projected for 2050) and 48% with 1.7 m of SLR (projected for 2100). Habitat conversion was more drastic in wetlands with larger proportions of marsh habitats relative to subtidal habitats and occurred more rapidly in small lagoons relative to larger sites. Our assessment can inform management of coastal wetland vulnerability, improve understanding of the SLR drivers relevant to individual wetlands, and highlight significant data gaps that impede SLR response modeling across spatial scales. This approach augments regional SLR assessments by considering spatial variability in SLR response drivers, addressing data gaps, and accommodating wetland diversity, which will provide greater insights into regional SLR response that are relevant to coastal management and restoration efforts.  相似文献   

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Despite the increasing impact of atmospheric nitrogen (N) deposition on terrestrial greenhouse gas (GHG) budget, through driving both the net atmospheric CO2 exchange and the emission or uptake of non-CO2 GHGs (CH4 and N2O), few studies have assessed the climatic impact of forests and grasslands under N deposition globally based on different bottom-up approaches. Here, we quantify the effects of N deposition on biomass C increment, soil organic C (SOC), CH4 and N2O fluxes and, ultimately, the net ecosystem GHG balance of forests and grasslands using a global comprehensive dataset. We showed that N addition significantly increased plant C uptake (net primary production) in forests and grasslands, to a larger extent for the aboveground C (aboveground net primary production), whereas it only caused a small or insignificant enhancement of SOC pool in both upland systems. Nitrogen addition had no significant effect on soil heterotrophic respiration (RH) in both forests and grasslands, while a significant N-induced increase in soil CO2 fluxes (RS, soil respiration) was observed in grasslands. Nitrogen addition significantly stimulated soil N2O fluxes in forests (76%), to a larger extent in grasslands (87%), but showed a consistent trend to decrease soil uptake of CH4, suggesting a declined sink capacity of forests and grasslands for atmospheric CH4 under N enrichment. Overall, the net GHG balance estimated by the net ecosystem production-based method (forest, 1.28 Pg CO2-eq year−1 vs. grassland, 0.58 Pg CO2-eq year−1) was greater than those estimated using the SOC-based method (forest, 0.32 Pg CO2-eq year−1 vs. grassland, 0.18 Pg CO2-eq year−1) caused by N addition. Our findings revealed that the enhanced soil C sequestration by N addition in global forests and grasslands could be only marginally offset (1.5%–4.8%) by the combined effects of its stimulation of N2O emissions together with the reduced soil uptake of CH4.  相似文献   

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