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1.
Payments for environmental services (PES) aim to improve the supply of environmental services by making payments to service providers, which are conditional on the provision of those services. Payments cannot be conditional unless the service can be effectively monitored, making monitoring of service provision a central feature of PES. We introduce a framework for designing monitoring programmes in PES schemes for biodiversity conservation. We suggest that decisions must be made concerning the indicators to be used (e.g. species, threats or positive actions), how they will be monitored (e.g. using ground-based or remote-sensed data) and how the monitoring information will be used to differentiate payments (e.g. trends over time, performance relative to neighbouring sites, performance against a target). We then use this framework to examine the feasibility of monitoring species and threat indicators in a community-based biodiversity payment scheme in Menabe, Madagascar. We find that detecting population changes, differences between sites, or whether a target has been met is only feasible for the most common indicators, suggesting that it may not be possible to base payments on the species conservationists are most interested in. If payments need to be based on relatively common indicators, threat indicators may be more appropriate than common species indicators due to a stronger relationship to the service of interest (presence of a rare species). It is, however, possible to incorporate information from rare indicators using accumulation curves to compare between sites. This study highlights the impact of indicator choice on the monitoring effort required in a biodiversity PES. We urge caution in the design of payment schemes and suggest it can be detrimental to structure a scheme around an indicator that cannot be effectively monitored.  相似文献   

2.
Changes in landscape pattern under the control of agriculture intensification are considered to be an important driver of biodiversity and often a threat for conservation. The response of species to landscape changes is complex, including possible time lags, and depends on the taxonomic group. The search for surrogate species or surrogate data for biodiversity is confronted with this complexity.This study was conducted on two taxonomic groups (birds and vascular plants) for 20 sites each of 1 km2 equally distributed in the Seine valley floodplain. For plants, two habitats were studied: grasslands and hedges. We used a generalised additive model (GAM) and co-inertia analyses to determine whether present or past landscape attributes can best explain the biodiversity components (structure and composition). This study confirms the major role of landscape pattern attributes for predicting some metrics of biodiversity, e.g. species richness. But this study shows that potential drivers of biodiversity come from both the past and present landscape patterns. The quality of surrogates for biodiversity is strongly dependent on understanding the importance of past conditions. This suggests the need for more functional surrogates, taking into account the situation of equilibrium or non-equilibrium between biodiversity and its drivers.  相似文献   

3.
Temperate Australia’s wheat/sheep zone and much of Western Europe have both experienced dramatic declines in native bird populations associated with agricultural landscapes. We compare recent conservation strategies on private land in the context of each region’s historical agricultural development and the ecology of its bird fauna. Specifically, we consider which aspects of the conservation instruments and practices employed in European agricultural landscapes might be used to augment and inform approaches to private-land biodiversity conservation in Australia. Australian biodiversity conservation activities have focussed predominantly on remnant native vegetation and rarely target the agricultural matrix (i.e. land that is primarily used for agricultural production). However, declining species include those that not only primarily inhabit woodland, but also species for which components of the agricultural matrix are important, or even their main, habitat. In contrast, in Europe a range of conservation activities undertaken through agri-environment schemes focus explicitly on the management of the agricultural matrix. Whilst the different approaches to conservation on private land in Australia and Europe reflect the two continents’ different ecologies, land-use histories and political economies of agriculture, there are a number of parallels between bird population declines in the two regions, and an opportunity may exist to incorporate some of the successful aspects of the European agri-environment approach into emerging stewardship schemes in Australia. We suggest that the long-term nature of European agri-environment agreements, the principle of landholder payments more commensurate with reduced production opportunity and management actions specifically targeted at the agricultural matrix, are features of the European scheme that could benefit both woodland- and matrix-inhabiting bird species in Australian agricultural landscapes.  相似文献   

4.
In order to face the large and worrying biodiversity decline in agricultural landscapes, important policy instruments like agri-environmental schemes (AES) have been implemented. Studies that have examined the ecological effects of AES are now numerous and generally use indicators of biodiversity such as species richness and diversity as well as species abundance. Yet, it has been shown that simple metrics such as species richness or abundance may give misleading messages about biodiversity status and fate. Moreover, those indicators cannot detect another important source of biodiversity loss, biotic homogenisation. In this context, taking into account to a wider extent ecological difference among species would be more relevant, as well as focusing on the species specialisation which is known to be linked to higher species vulnerability. A bibliographic review investigating the criteria generally used to assess the success of AES showed that 55% of studies used species richness and/or abundance exclusively without any consideration of specialisation or other ecological traits in their evaluation of AES effectiveness. Based on data from the French breeding bird survey and studies at regional scale in France on farmland birds, we show that: (i) species richness and specialisation are generally negatively correlated in agricultural areas, (ii) habitat heterogeneity does not benefit specialist species, and (iii) monitoring of species diversity should be coupled with the monitoring of specialist species to improve conservation strategies in farming systems. Overall, this study emphasizes the need to account for both community richness and composition when assessing AES or similar conservation planning.  相似文献   

5.
Alpine areas are important biodiversity reservoirs, but are subject to anthropogenic drivers including climate change, nitrogen deposition and changing land use. Alpine vegetation has been proposed as an indicator of climate change impacts, but this requires long-term data since these communities have high inertia. Most studies have focussed on climate impacts in open, high-alpine summit communities; we investigated responses of closed low- and middle-alpine communities to multiple drivers. Scottish alpine vegetation data collected 1963-1987 was used as a baseline to assess biodiversity change across a range of habitats and a wide geographic spread. Change was assessed over a 20-40 years period using a variety of metrics including α- and β-diversity indices and biodiversity changes were contrasted between habitats and areas. We also examined changes in key species′ distribution and cover. Species richness increased in most habitats, while diversity at the plot scale and β-diversity declined, resulting in increased homogeneity of vegetation. This occurred in closed alpine communities over a 20-40 years period, implying that these communities are considerably more dynamic than previously thought. Key northern and alpine species declined while lowland generalist species increased. This change was consistent with predicted impacts of climate change, but other elements of spatial pattern (decline in lichen richness in high deposition areas) were consistent with effects of nitrogen pollution. Assessment of biodiversity change differed according to the metrics used and we argue that biodiversity targets for conservation management need accurate definition and that multiple measures of biodiversity are required to accurately assess long-term change.  相似文献   

6.
Participation by local communities in the assessment and monitoring of efforts to implement global environmental conventions (GECs), such as Convention on Biological Diversity (CBD) and the UN Convention to Combat Desertification (UNCCD), is a topic of growing interest worldwide. Previous implementation efforts were constrained by the lack of a methodological framework that integrates local knowledge and ecological methods. This study, conducted with assistance from Maasai herders in northern Tanzania, evaluated a socio‐economic and ecological framework for integrating local communities into assessments of the GECs. To reach decisions related to CBD, herders used livestock grazing suitability (GS) and proxy indicators of biodiversity, while to reach decisions related to CCD herders used potential grazing capacity (PGC) related to the risk of degradation. We proposed criteria for indicator selection and developed step‐wise research methods to assess performance of the indicators at spatial scales. The ecological and anthropogenic indicators were then analysed using a correlation matrix to evaluate management decisions. We showed that changes in ecological indicators influenced herder decisions. The anthropogenic indicators for potential were more sensitive to changes in soil degradation, range conditions and trends; while the decisions related to GS were more sensitive to the majority of the proxy indicators of biodiversity. The decisions reflected the potential responses to management, which had implications for CBD and CCD. Because decisions constitute a multiplicity of activities, the responses by local communities could be related to the potential role played by each indicator in the implementation of the convention at the local level. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

7.
There are disagreements on the use of standard biodiversity monitoring methods to promote community participation. This study combined three methods to investigate questions why monitor biodiversity, what biodiversity to monitor and how participatory biodiversity monitoring can be promoted in central Uganda in East Africa. The question of why biodiversity should be monitored concerns the justification for monitoring, while the question of what to monitor concerns the choice of biodiversity variables, and the question of how to monitor biodiversity concerns the links between the data generated from monitoring and problems associated particularly with regard to community participation. The study selected landscape and sampling scales (i.e. plots) for participatory monitoring of biodiversity. Herders identified main landscape patches and plant species. Herder value‐weighted indicators, such as invasive species and range condition scores (i.e. composite indicators representing species palatability, composition, cover, density and richness) were used for measuring biodiversity in their grazing lands. To understand what biodiversity to monitor, we interpreted the correlation between biodiversity indicators and herder value‐weighted range conditions. Herders defined biodiversity from a utilitarian perspective, which is inconsistent with the conventional scientific goals of biodiversity conservation which focus on preservation of the total species pool. To address the question of how to monitor biodiversity, evidence from the folk taxonomy of sampled plant species and other proxy biodiversity indicators, including herder value‐weighted range condition scores, were compared to understand scale dependence. We inferred that the landscape scale monitoring was more sensitive to measuring biodiversity than the conventional scales of plots. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

8.
Increasing habitats diversity in agricultural landscapes has been proposed as a key measure for reversing the decline of farmland biodiversity in Europe. However, indicators used for assessing such a potential compensation effect usually only rely on species diversity and abundance while ignoring variations in species-specific vulnerability. The extent to which habitat diversity may reverse the decline of specialist species in Europe to farming systems is thus still unclear. In this study, we investigate whether the effect of non-cropped habitat diversity on farmland birds’ occurrences was dependent on species’ specialization for habitats. In particular, we focused on the relative effects of non-cropped habitat diversity on species’ abilities to persist or to colonize new vacant areas. We used a capture-recapture statistical framework to study the spatial dynamics of 20 farmland bird species in France monitored from 2001 to 2007. We found that non-cropped landscape diversity reduces both the probabilities that a species becomes extinct locally and that a species colonizes new vacant areas, and the occupancy rate. Although this suggests a possible stabilizing effect of the surrounding habitat diversity on species occurrence in farming systems, the occupancy was only weakly affected. Moreover, we found that the most specialist species were the more negatively affected by this landscape diversity in terms of colonization abilities. We argue that accounting for the differences in habitat specialization among farmland species can improve conservation policies dedicated to the management of landscape diversity.  相似文献   

9.
A significant policy objective is the need for protection of biodiversity not just within designated Natura 2000 sites, but also in areas that occur outside of these sites. However there is a lack of information on existing semi-natural habitat cover on EU farms, making it difficult to assess whether targets for halting the loss of agricultural biodiversity are being met. To achieve these targets, reliable yet easy-to-use methods are needed for accurately identifying priority areas for conservation actions and monitoring biodiversity on a large spatial scale.Remote sensing, farmland statistics and species data have been used in some EU countries to create maps to estimate the extent of semi-natural habitat cover but these are acknowledged as being too broad scale. In this study, we examined a method of fine-scale prediction of the spatial coverage of semi-natural habitats in lowland farms. A generalized additive model (GAM) was used to investigate the relationships between landscape and farm management variables and the lowland farmland habitat biodiversity on 32 farms outside of conservation designations, in a region of western Ireland. Semi-natural habitat cover on lowland farms could be predicted with a model using stocking density, soil diversity and river and stream length. It is proposed that this model could be used to predict the coverage of semi-natural habitats on farms in other regions of Ireland with similar land-use and landscape. A similar modelling approach could be adapted for application in other regions of Ireland and across Europe with different landscapes to predict semi-natural habitat coverage.  相似文献   

10.
In recent times there has been a growing dichotomy between preservation of single species and broader, ecosystem-based approaches to conservation. Freshwater habitats are among the most highly human-impacted ecosystems. We used a long-term data set on black kites (Milvus migrans), a threatened raptor dependent on aquatic habitats, to explore ways to reconcile single species and biodiversity-driven approaches to conservation. In the pre-Alpine lakes of northern Italy, black kite populations showed medium-low density, extremely low breeding success and widespread declines. Spatio-temporal variations showed density and breeding success to be positively related to ecosystem productivity (as estimated by phosphorus concentrations in lakes), availability of aquatic habitats and grassland, and to be negatively related to extent of farmland and fish harvest by professional fishermen. Fish species richness, used as a surrogate of biodiversity, was highest in one oligotrophic lake, but on average increased with increasing ecosystem productivity (i.e. lake eutrophication). Given expected future declines in ecosystem productivity, kite conservation will be helped by enhancing populations of alternative prey in terrestrial habitats (e.g. through incentives for grassland), and higher regulation of fish harvest. On the other hand, ecosystem management may profit from the use of black kites or other aerial piscivores as indicators of biodiversity and of diffuse ecosystem stress, such as sustainability of fishing practices.  相似文献   

11.
We used dung beetles as an indicator group to identify the most important habitats for biodiversity conservation in a Mediterranean traditional agroecosystem. The relationships between traditional grazing and farming activities and biodiversity were analysed by comparing species richness and temporal turnover across three different habitat types, defined according to vegetation structure and human land use. In this study, both spatial (landscape, among-habitats) and temporal (intra-annual, seasonal) analyses were contemplated at mesoscale.The measurement and use of temporal beta diversity (i.e. an index of temporal species turnover) in conservation biology showed that it is a simple method to characterize and compare different habitat species-assemblages, particularly when time seems to be a significant factor in explaining biodiversity features.Our results showed open mosaic areas as the richest and most temporally heterogeneous habitats. We suggest the maintenance of traditional human activities carried out in these areas, since they have been a significant diversification agent, to avoid the loss of the high Mediterranean biological diversity.  相似文献   

12.
Long-term, locally-based biodiversity monitoring programs are essential for understanding and mitigating the effects of global change on tropical biodiversity while providing capacity-building, environmental education, and public outreach. However, these programs are lacking in most tropical countries. Birds are the best-known major group of organism, comprise excellent environmental indicators, are relatively easy to monitor, and are met with enthusiasm and interest by people worldwide. Bird monitoring programs using mist nets and bird banding (ringing) are especially valuable, as these well-established techniques enable the use of capture-mark-recapture (CMR) models to measure population change and other demographic parameters. Equally important for conservation, the ability to capture and release birds makes it possible to provide hands-on ornithological training and educational activities to students, conservationists, villagers, decision-makers, journalists, and other local people. Bird banding programs provide local jobs for research assistants, who often go on to productive careers in conservation, education, research, or ecotourism. Long-term bird banding stations also provide the nuclei, infrastructure, and staff for monitoring, education, and conservation programs focused on other taxa. As successful examples from Costa Rica and Ethiopia show, bird monitoring programs that integrate conservation, ecological research, environmental education, capacity-building, and income generation are cost-effective tools to achieve the goals of community-based biodiversity conservation and poverty reduction in the developing world. Therefore, locally-based and long-term bird monitoring programs should be encouraged, established, and funded throughout the tropics.  相似文献   

13.
Ecological regionalizations, such as ecoregions or environmental clusters, are often used as coarse filters for conservation. To be effective biodiversity surrogates, regionalizations should contain distinct species assemblages. This condition is not frequently evaluated and regionalizations are rarely assessed comparatively. We used a national dataset of Canadian butterfly collections to evaluate four regionalizations (ecoregions, land cover and productivity regime classifications, and a spatial grid) at two thematic resolutions using analysis of similarity (ANOSIM) and species indicator values. Overall, the spatially constrained schemes (ecoregions and grids) best captured patterns of butterfly community composition and species affinities, indicating that butterfly communities are strongly structured by space at the continent scale. In contrast, when comparing regions only within spatial or environmental neighbourhoods (i.e., comparing between regions that are adjacent along geographic or environmental gradients), all regionalizations performed similarly. Adjacency in environmental space is thus as important as physical adjacency at determining community dissimilarity. Productivity regimes and land cover will be useful biodiversity surrogates when considered in conjunction with space or within a spatially constrained area. This finding was confirmed with two ecoregional case studies (of the Algonquin-Lake Nipissing and Thompson–Okanagan Plateau ecoregions), which also revealed that the relative performance of regionalizations depends upon the context of the study area. We conclude that including species data can improve the efficiency of environmental surrogates for systematic conservation planning.  相似文献   

14.
Critical to the conservation of biodiversity is knowledge of status and trends of species. To that end, monitoring programmes have reported on the state of biodiversity using reference conditions as comparison. Little consensus exists on how reference conditions are defined and how such information is used to index intactness. Most use protected areas or an arbitrary year as reference. This is problematic since protected areas are often spatially biased, while arbitrarily defined reference years are often not sufficiently distant in time. We propose an alternative that relies on empirical estimates of reference conditions. Statistical ranges of reference are estimated and compared with observed occurrence and abundance to index status of individual species. When averaged among species, overall intactness is estimated. We demonstrate the approach using 202-winter mammal tracking sites from the boreal forest of Alberta, Canada. Intactness was estimated at 89 out of 100 with the southern boreal having lowest intactness and greatest human footprint. We suggest empirical predictions of reference conditions be used as baselines for comparing changes in the state of species and biodiversity. Reporting can occur at any spatial (e.g., ecosystem) or hierarchical (e.g., species, guilds, taxonomic group, or overall biodiversity) scale and is easily interpreted (scaled from 0-degraded to 100-intact). When used in a long-term monitoring framework, statistical trends in biodiversity intactness can be estimated, individual status of species assessed, and relevant policy evaluated.  相似文献   

15.
In Europe, land use changes follow public policies, and particularly the Common Agricultural Policy. To predict the effect of policies on agricultural practices, landscape, and ultimately biodiversity, requires understanding of the interactions between social, economic and ecological dynamics at regional scale. We studied by means of prospective scenarios the possible effects of agricultural changes on biodiversity in a Mediterranean upland. This area is characterised by extensive grasslands that have been maintained for centuries by agriculture and are now threatened by tree and shrub encroachment. We built four scenarios that describe possible changes in agricultural EU policies by 2030. We selected 15 bird species on the basis of a high natural heritage responsibility of the study area for these species and 45 plant species on the same basis plus local rarity and habitat vulnerability. We analysed how these species were affected by the four scenarios by considering changes in their habitats. For each scenario, we analysed the driving forces that determine land use changes. Landscape dynamics was modelled with a Generalised Linear Model combining environmental and land use factors. Most of the 60 selected species depend on open habitats. Only the scenario where public support was only granted if it provided environmental services had a positive impact on open habitats and their associated biodiversity. This ‘natural heritage’ scenario was also rated positively by local stakeholders. This approach sheds light on the interest of inter/transdisciplinary studies, scenarios, and stakeholder involvement in the definition of public policies for biodiversity conservation.  相似文献   

16.
17.
Effective biodiversity conservation requires an analysis of the existing reserve system. In temperate and boreal regions, plant diversity has a strong positive association with soil pH. Consequently, in order to protect plant diversity effectively, a relatively large proportion of protected areas should be on high pH soils. Since biodiversity data are never complete for all taxa, biodiversity indicators, e.g., threatened species, should be used. We studied soil pH distributions in protected areas in Northern Europe and tested whether soil pH requirement differs between threatened and non-threatened bryophyte and vascular plant species. As result, the proportion of high pH soils in protected areas was significantly greater than the proportion of these soils in general. This ensures that a large regional pool of plant species preferring high pH soils is relatively well protected. Threatened and non-threatened species in Northern Europe did not differ in their soil pH requirements, but threatened species required a narrower soil pH range than non-threatened species. Consequently, threatened species diversity can be used for indicating overall plant diversity.  相似文献   

18.
Conservation biology is mainly interested in prioritizing sites on the basis of their high biodiversity. Although species richness is a commonly used criterion, it does not take other crucial aspects of identifying conservation priority sites into account, such as rarity or taxonomic distinctness. Additionally, management efforts are usually focused on the conservation of a small number of species, mainly vertebrates. However, the biodiversity patterns of these faunal groups and the main factors which determine them cannot be generalized to other faunal groups (e.g. aquatic invertebrates). Therefore, the objectives of the present study are: (1) to compare the response of 11 biodiversity metrics in order to know which ones are redundant, (2) to identify key environmental factors for biodiversity, and (3) to find out whether sites with high biodiversity values also have a good habitat condition and high protection status. The study was done at assemblage level (crustaceans and insects) in 91 wetlands in the NE Iberian Peninsula. Regression tree models were used to identify the key factors influencing biodiversity, including water, wetland and landscape characteristics as explanatory variables. Generalized Linear models were used to establish the relationship between biodiversity metrics and protection status and habitat condition. The results obtained by the two sampled seasons were compared. Conductivity was the main factor influencing biodiversity metrics. Positive significant relationships were found between some biodiversity metrics and wetland habitat condition, whereas there were none for protection status, indicating the inadequacy of conservation policies to protect wetland aquatic invertebrate biodiversity.  相似文献   

19.
中国的农业生物多样性保护及持续利用   总被引:16,自引:0,他引:16  
中国农区内分布有丰富的野生珍稀濒危物种、生境和遗传基因资源,是农业生物多样性保护的重点。中国农业栽培、繁殖及野生生物物种种类繁多,其物种和生境类型都具特有性,由于农业土地的过度开发和不合理利用,以及农业生态环境污染、过量采集等因素,造成我国农业生物多样性品种和分布面积缩小或消失。我国从50 年代开始保护生态系统的工作,特别是在改革开放以来,我国政府在就地保护、迁地保护、保护规划、法制建设、机构建设、宣传培训等方面,采取了一系列的保护措施,农业生物多样性保护和持续利用取得了显著成效。  相似文献   

20.
Since the second half of the 20th century, the intensification of land-use practices and the associated decline in semi-natural habitats have been the major drivers of farmland biodiversity loss. In many marginal agricultural systems, a structural transformation of farms, from small and traditional to large and intensive, has also been observed. We unravelled the impact of farm size and slope on plant, orthopteran and butterfly diversity in 132 hay meadows in a region of the Italian Alps. We defined three farm size classes representing different levels of intensification and used mixed models to test the influence of farm size along with topographic slope. The diversity of plants, orthopterans and butterflies declined with management intensity at the field scale, which mainly depended on farm size and grassland topography. We found a positive effect of slope and a negative influence of farm size on species richness of the three taxonomic groups. Large farms were strongly associated with higher production of organic fertilizers and higher soil fertility than small traditional farms, irrespective of meadow slope. At the regional scale, we found that large farms managed flatter meadows (slope = 9.0) than small traditional farms (slope = 13.5), contributing to the abandonment of steep species-rich grassland areas. Regional stakeholders should consider targeted conservation schemes to prevent the ongoing substitution of small farms with large intensive farms. A complementary solution could be to target future conservation measures to support farms with low production of organic fertilizers and to reward the maintenance of the current management of steep meadows.  相似文献   

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