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1.
The limited resources available for the conservation of biodiversity and ecosystem services call for prioritisation schemes. For instance, in the process of systematic conservation planning site selection is partly determined by efficiency gains. In this paper we present an alternative method for global spatial priority-setting based on ecological indicators, combined with social and economic conditions that influence the effectiveness of conservation, and measures for the long-term persistence of biodiversity. In the analysis the assumption made is that nature conservation should prioritize the effective maintenance of functional ecosystems that do not only provide the most ecosystem services but are also more likely to have a high adaptive capacity towards unavoidable environmental change. Furthermore, the effectiveness and permanence of conservation projects is tied to certain socioeconomic and political conditions that, as we suggest, should be evaluated as part of the conservation priority-setting process. We propose three new priority categories: eco-functionally wise (EcoWise), socioeconomically wise (SocioWise) and proactive allocation of conservation resources considering future climate change (ClimateWise) expressed as indices based on 16 different indicators. Analysing the combined effects of these three categories (EcoSocioClimateWise), in a spatially explicit way highlights the importance of tropical, subtropical but also some temperate and boreal forest areas all of which are characterized by high values of vegetation density, tree height and carbon storage. Our recommendations for policy makers prompt a shift in conservation planning towards advocating the use of ecological and socioeconomic indicators in combination with proxies for the vulnerability to future climate change impacts.  相似文献   

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Future battlegrounds for conservation under global change   总被引:2,自引:0,他引:2  
Global biodiversity is under significant threat from the combined effects of human-induced climate and land-use change. Covering 12% of the Earth's terrestrial surface, protected areas are crucial for conserving biodiversity and supporting ecological processes beneficial to human well-being, but their selection and design are usually uninformed about future global change. Here, we quantify the exposure of the global reserve network to projected climate and land-use change according to the Millennium Ecosystem Assessment and set these threats in relation to the conservation value and capacity of biogeographic and geopolitical regions. We find that geographical patterns of past human impact on the land cover only poorly predict those of forecasted change, thus revealing the inadequacy of existing global conservation prioritization templates. Projected conservation risk, measured as regional levels of land-cover change in relation to area protected, is the greatest at high latitudes (due to climate change) and tropics/subtropics (due to land-use change). Only some high-latitude nations prone to high conservation risk are also of high conservation value, but their high relative wealth may facilitate additional conservation efforts. In contrast, most low-latitude nations tend to be of high conservation value, but they often have limited capacity for conservation which may exacerbate the global biodiversity extinction crisis. While our approach will clearly benefit from improved land-cover projections and a thorough understanding of how species range will shift under climate change, our results provide a first global quantitative demonstration of the urgent need to consider future environmental change in reserve-based conservation planning. They further highlight the pressing need for new reserves in target regions and support a much extended 'north-south' transfer of conservation resources that maximizes biodiversity conservation while mitigating global climate change.  相似文献   

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The representation of root activity in models is here confined to considerations of applications assessing the impacts of changes in climate or atmospheric [CO2]. Approaches to modelling roots can be classified into four major types: models in which roots are not considered, models in which there is an interplay between only selected above-ground and below-ground processes, models in which growth allocation to all parts of the plants depends on the availability and matching of the capture of external resources, and models with explicit treatments of root growth, architecture and resource capture. All models seem effective in describing the major root activities of water and nutrient uptake, because these processes are highly correlated, particularly at large scales and with slow or equilibrium dynamics. Allocation models can be effective in providing a deeper, perhaps contrary, understanding of the dynamic underpinning to observations made only above ground. The complex and explicit treatment of roots can be achieved only in small-scale highly studied systems because of the requirements for many initialized variables to run the models.  相似文献   

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Conservation agriculture (CA) is widely promoted as a sustainable agricultural management strategy with the potential to alleviate some of the adverse effects of modern, industrial agriculture such as large‐scale soil erosion, nutrient leaching and overexploitation of water resources. Moreover, agricultural land managed under CA is proposed to contribute to climate change mitigation and adaptation through reduced emission of greenhouse gases, increased solar radiation reflection, and the sustainable use of soil and water resources. Due to the lack of official reporting schemes, the amount of agricultural land managed under CA systems is uncertain and spatially explicit information about the distribution of CA required for various modeling studies is missing. Here, we present an approach to downscale present‐day national‐level estimates of CA to a 5 arcminute regular grid, based on multicriteria analysis. We provide a best estimate of CA distribution and an uncertainty range in the form of a low and high estimate of CA distribution, reflecting the inconsistency in CA definitions. We also design two scenarios of the potential future development of CA combining present‐day data and an assessment of the potential for implementation using biophysical and socioeconomic factors. By our estimates, 122–215 Mha or 9%–15% of global arable land is currently managed under CA systems. The lower end of the range represents CA as an integrated system of permanent no‐tillage, crop residue management and crop rotations, while the high estimate includes a wider range of areas primarily devoted to temporary no‐tillage or reduced tillage operations. Our scenario analysis suggests a future potential of CA in the range of 533–1130 Mha (38%–81% of global arable land). Our estimates can be used in various ecosystem modeling applications and are expected to help identifying more realistic climate mitigation and adaptation potentials of agricultural practices.  相似文献   

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Abundance indices from transect surveys for species restricted to prairies and barrens were correlated to test the degree to which these species of conservation concern co-occur. In 56 pair-wise tests among 15 species by subregion, 29 (52%) correlated significantly, all but one positively, and only 17 (37%) of 46 tests involving samples of >60 individuals for each species were non-significant. The species producing the most significant interspecific correlations in prairie were Speyeria idalia (five of ten tests) and Atrytone arogos (four of six tests); in barrens, Euchloe olympia (seven of eight tests) and Hesperia l. leonardus (six of eight tests). Lycaeides melissa samuelis, the butterfly receiving the most conservation attention in these habitats, produced few significant correlations. To explicate these patterns of co-occurrence, case histories were compiled for these species at sites of comparable vegetation by subregion. No management type was clearly favourable for all specialists of a given habitat, although some managements were favourable for more species than others (e.g. haying vs. burning in prairie). Analysis of variance of management at these sites produced more results with significant effects than did correlations of the species' abundance indices with habitat patch size. These results were inconsistent with prevailing ecological theory about the natural maintenance of these habitats; conversely, a single unified (alternative) theory of ecosystem management could not be inferred from these results. These patterns of butterfly co-occurrence suggest an alternative approach to ecosystem conservation that focuses on subsets of species native to a particular ecosystem. These smaller species assemblages significantly co-occur in range, habitat, and management tolerance, and may be amenable to monitoring with indicator species.  相似文献   

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Mangrove conservation: a global perspective   总被引:1,自引:0,他引:1  
Mangroves are of great ecological importance and socio-economic significance as a hub for tropical marine biotope. The mangroves are also one of the world’s richest storehouses of biological and genetic diversity. Furthermore, 90?% of the marine organisms spend part of their life in this ecosystem and 80?% of the global fish catches are dependent on mangroves. In addition, mangroves and their associated biota are identified as a promising source of natural and novel drugs. On the other hand, scientific community finds such an ecosystem as one among the world’s most threatened biome due to human intervention in the long past and on-going climate change. Already many countries lost their huge mangrove wealth within the last two decades. Further, decline of the mangrove cover may cause an irreparable damage of ecosystem service to mankind. Now it is high time to conserve the precious ecosystem in order to maintain a stable and healthy coastal environment.  相似文献   

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Tropical dry forests (TDFs) are ecosystems that present stresses for woody species, and these stresses are expected to filter out many lineages that do not adapt to these stressful environments. In most cases, in the Andes, only small fragments of these forests remain with different conservation conditions in a gradient of altitude and stresses. This work aimed to answer whether taxonomic and phylogenetic diversities increase or decrease with increasing altitude in the Andes TDFs. The working hypothesis was that the variation in altitude determines the taxonomic and phylogenetic diversity of the Andes TDFs. The study was carried out through a floristic census in seven different locations in an Andean slope with altitudes ranging from 282 up to 799 m ASL. In each location, 20 plots of 25-m?×?4-m were established, totaling 140 plots. Taxonomic and phylogenetic diversity indices were estimated. We also used principal component analysis to describe the influence of climatic variables at the seven study sites. We found the influence of environmental filtering in the studied sites. As climatic seasonality increases and altitude decreases, taxonomic and phylogenetic diversity decrease and phylogenetic clustering increases. The major concern in a global warming scenario is that increasing the effects of high temperatures and droughts could extinct species and phylogenetic lineages as TDF fragmentation prevents species from migrating upwards in the mountains. Therefore, to promote connectivity is a priority besides stop habitat loss of TDFs.

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The putative peculiarities of island insects and the factors important in their conservation are noted. Endemism and speciation lessons from island insects have contributed significantly to wider understanding of aspects of insect diversification. The twin complexes of threats to island insects involve (1) internal processes, essentially habitat changes by human activity, and their consequences and (2) externally-imposed effects from alien invasive species, both of these operating in environments that may lack much of the buffer capability present in larger continental areas or in richer communities. Many island insects now persist only in small inaccessible remnant habitats, and protecting these is a key theme in planning insect conservation on islands. The possible effects of climate change may be severe, particularly on ‘low islands’ such as many coral cays.  相似文献   

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Hantaviruses are comprised of tri-segmented negative sense single-stranded RNA, and are members of the Bunyaviridae family. Hantaviruses are distributed worldwide and are important zoonotic pathogens that can have severe adverse effects in humans. They are naturally maintained in specific reservoir hosts without inducing symptomatic infection. In humans, however, hantaviruses often cause two acute febrile diseases, hemorrhagic fever with renal syndrome (HFRS) and hantavirus cardiopulmonary syndrome (HCPS). In this paper, we review the epidemiology and epizootiology of hantavirus infections worldwide.
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Climate change is now considered the greatest long-term threat to coral reefs, with some future change inevitable despite mitigation efforts. Managers must therefore focus on supporting the natural resilience of reefs, requiring that resilient reefs and reef regions be identified. We develop a framework for assessing resilience and trial it by applying the framework to target management responses to climate change on the southern Great Barrier Reef. The framework generates a resilience score for a site based on the evaluation of 19 differentially weighted indicators known or thought to confer resilience to coral reefs. Scores are summed, and sites within a region are ranked in terms of (1) their resilience relative to the other sites being assessed, and (2) the extent to which managers can influence their resilience. The framework was applied to 31 sites in Keppel Bay of the southern Great Barrier Reef, which has a long history of disturbance and recovery. Resilience and ‘management influence potential’ were both found to vary widely in Keppel Bay, informing site selection for the staged implementation of resilience-based management strategies. The assessment framework represents a step towards making the concept of resilience operational to reef managers and conservationists. Also, it is customisable, easy to teach and implement and effective in building support among local communities and stakeholders for management responses to climate change.  相似文献   

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