首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 952 毫秒
1.
It is becoming increasingly difficult to manage and expand statutory conservation areas (i.e., parks and formally protected areas). Therefore, alternative opportunities for land conservation merit closer attention. This paper examines the extent to which privately owned conservation areas contribute to biodiversity representation. Gap analyses were performed for a large semi-arid region in South Africa with a comprehensive database of private conservation areas. The distribution of private conservation areas was compared to statutory conservation areas using several landscape characteristics: biome and vegetation variant, elevation class, ecological process area, total area, and threat status (endangerment). Conservation target achievement for the vegetation variants was also assessed, as was the degree to which private conservation areas complemented statutory conservation areas by representing different landscape characteristics. The number of targets achieved nearly tripled if private conservation areas were considered in addition to statutory conservation areas. Further, private conservation areas significantly complemented statutory conservation areas in the types of biomes, elevation classes, and threat status classes conserved. Private conservation areas were especially important in conserving lower elevation habitat, and by association, endangered vegetation. This particular relationship is expected to be common worldwide. Our results indicate that private lands conservation deserves an increased allocation of resources for both research and implementation.  相似文献   

2.
While many countries have developed and expanded efforts to sustain and enhance the protection of biodiversity, the effectiveness of such programs, as well as the manner in which funds are distributed, has been questioned. We examined funding allocation decisions for species conservation in Spain at different governmental scales. Several factors that may impact conservation spending patterns and policy decisions were examined, including available scientific data, current scientific policies, and public awareness and perceptions of conservation needs. Our analyses revealed a strong connection between existing conservation policies and scientific information, research priorities and public concern. We found that there is a substantial bias in the taxa that are studied, the funding levels for those studies and public policy which triggers and supports the studies. The relationships, however, are not strictly cause and effect, but are instead enmeshed in a complex feed-back system in which conventional scientific activity acts as the main driver but is itself influenced by both policy and public perception. By acknowledging both the essential role of science in this system and the critical factors that can influence the acquisition of scientific information, a constructive dialog can be established that will propel conservation activities to a more productive and environmentally sound outcome.  相似文献   

3.
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   

4.
Understanding the causes, processes and ecological consequences of land use change is a conservation priority in fragmented, human dominated landscapes but is often difficult due to insufficient environmental and social data or data at different spatial scales. We assessed changes in the extent of relictual native grasslands in western Victoria, Australia, by comparing native grasslands recorded by targeted vegetation surveys in the 1980s and early 1990s, with those present in 2004. Of the 880 ha of native grassland recorded by the earlier surveys, approximately 225 ha were destroyed by 2004. The area of grassland on road reserves was reduced by 169 ha (36%), with 67 ha (32%) and 18 ha (14%) lost from private property and Crown land, respectively. However, due to incomplete surveys in 1984, the area of private native grassland destroyed is likely to have been severely underestimated. Bayesian logistic regression models determined that social factors had a greater influence on the probability of native grassland destruction than environmental variables (i.e. soil type, distance to stream). The conservation ranking of native grassland patches and the fire brigade area the patch was located in were found to be particularly important. These results highlight the destructive effect of altering roadside fire prevention techniques from controlled burning to herbicide spraying, but suggest that this change is due to a complex interaction of social, economic and cultural factors.  相似文献   

5.
生态移民是新形势下中国扶贫开发的重要战略举措,研究采用参与性农户评估方法,以广西环江县30个典型移民安置屯为例,开展生态移民背景下移民迁入区人地关系研究,将调查农户划分为迁入农户和原驻地农户,通过对比2组农户的现有耕地面积、经济收入以及对移民政策和环境变化的响应等问题,探讨移民迁入区的移民效应和可持续性.研究表明:生态移民工程受到农户的普遍认可与支持,迁入农户占有的耕地资源质量和经济收入较搬迁前有大幅度提高,土地利用与农业种植业结构进一步优化.但仍需关注迁入区移民较原驻民耕地占有量和经济发展速度偏低、迁入区人口增加对土地资源和生态环境可持续利用造成的冲击等问题.  相似文献   

6.
Land degradation is considered to be a major environmental problem by scientific and political institutions in Iceland. In past years, land degradation problems related to sheep and horse grazing have gradually come to the fore in public discussion of environmental questions. However, land degradation is often evaluated in different ways by different groups of people. This has led to a lack of consensus regarding rates and severity of land degradation. Therefore, it is important to study differences in environmental perception, and how these differences can be dealt with in the context of sustainable management. This paper aims to highlight farmers' perception of land degradation in Iceland, as perceptions of the environment determine the basis for human activities related to the land. A total of 100 farmers in NE Iceland were questioned and interviewed for their opinions on land degradation, its history, causes and severity. The results indicate that farmers consider land degradation to be a slow process, and not a catastrophic phenomenon. The understanding of the general ecological processes by the users affects their practices and concern for their environment. This feeds back on the land‐use system and ultimately causes changes in land‐cover. Therefore, if we are to increase our understanding of the processes that lead to land‐cover changes we have to integrate the perceptions of land users and technical experts. In this way we may improve conservation practices and land‐resource management policies. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   

7.
Despite their high diversity and importance for humankind, invertebrates are often neglected in biodiversity conservation policies. We identify seven impediments to their effective protection: (1) invertebrates and their ecological services are mostly unknown to the general public (the public dilemma); (2) policymakers and stakeholders are mostly unaware of invertebrate conservation problems (the political dilemma); (3) basic science on invertebrates is scarce and underfunded (the scientific dilemma); (4) most species are undescribed (the Linnean shortfall); (5) the distribution of described species is mostly unknown (the Wallacean shortfall); (6) the abundance of species and their changes in space and time are unknown (the Prestonian shortfall); (7) species ways of life and sensitivities to habitat change are largely unknown (the Hutchinsonian shortfall).Numerous recent developments in taxonomy, inventorying, monitoring, data compilation, statistical analysis and science communication facilitate overcoming these impediments in both policy and practice. We suggest as possible solutions for the public dilemma: better public information and marketing. For the political dilemma: red-listing, legal priority listing and inclusion in environmental impact assessment studies. For the scientific dilemma: parataxonomy, citizen science programs and biodiversity informatics. For the Linnean shortfall: biodiversity surrogacy, increased support for taxonomy and advances in taxonomic publications. For the Wallacean shortfall: funding of inventories, compilation of data in public repositories and species distribution modeling. For the Prestonian shortfall: standardized protocols for inventorying and monitoring, widespread use of analogous protocols and increased support for natural history collections. For the Hutchinsonian shortfall: identifying good indicator taxa and studying extinction rates by indirect evidence.  相似文献   

8.
As China becomes increasingly influential in international affairs, it is important to understand the unique characteristics of Chinese environmental values and policy processes. This is especially true given the rate and scale of China’s environmental impacts on natural ecosystems from local to international levels. Currently, however, Chinese conservation values, policies and practices are not well-integrated. We identify four systemic barriers to conservation in China that contribute to this poor integration: weak rule of law; unclear land tenure; top down government authority; and disconnects between scientific research and management implementation. To advance China toward an environmentally secure future, we suggest that combining traditional Chinese environmental values with contemporary science and international conservation practices will help to create a ‘Conservation with Chinese Characteristics’. We do not believe that traditional values should replace modern science and management. Rather, we suggest that, given the cultural and political conditions in China today, using traditional values to frame contemporary environmental science and ecosystem-based management may create stronger societal support for conservation implementation.  相似文献   

9.
The problems of environmental change and biodiversity loss have entered the mainstream political agenda. Given the call from an increasingly influential environmental lobby for government and wider society to make both financial and personal sacrifices to address these problems, it seems likely that conservation biologists and environmental managers will be asked tough questions of the general form ‘are conservation interventions effective?’ and, ‘are they doing more good than harm?’ Science constantly advances and must remain open to challenge, but managers and policy formers require an interim product (an evidence-base) to underpin their current decision-making. The health services have been using the objective and transparent methodology of systematic review to summarise the evidence-base relating to the effectiveness of interventions. Environmental management has, up until now, had no formal shared evidence-base of this kind. Reviewing recent developments in evidence-based practice, this paper introduces a ‘systematic review’ section for this journal and argues that constructing an evidence-based framework for environment management is possible, the challenge is scaling it up to engage the global scientific community. We draw on the history of evidence-based healthcare, but also on the differences between healthcare and conservation, to set out the challenges in creating a Collaboration for Environmental Evidence that develops a library of systematic reviews on the effectiveness of conservation and environmental interventions.  相似文献   

10.
Human-modified tropical landscapes under semi-natural or agro-ecosystems often harbor biodiversity of significant conservation value. In the Western Ghats of India, these ecosystems also provide connectivity between protected areas and other remnant forests. We investigated the conservation value of these landscapes and agro-ecosystems using results from 35 studies covering 14 taxonomic groups. Large, conspicuous taxonomic groups and tree-covered land-use types have received much focus in this area of research in the Western Ghats. We computed a response ratio defined as the log ratio of species richness in human land use to species richness in forest control site from 17 studies. In a meta-analysis, we investigated variation of this ratio across studies with respect to three variables: taxonomic group, the land-use type sampled and the extent of forest cover within the study landscape. Higher forest cover within the landscape emerged as a major positive influence on biodiversity in human-modified landscapes for vertebrates and vegetation while no patterns emerged for invertebrates. Our results suggest that loss of remnant forest patches from these landscapes is likely to reduce biodiversity within agro-ecosystems and exacerbate overall biodiversity loss across the Western Ghats. Conservation of these remnant forest patches through protection and restoration of habitat and connectivity to larger forest patches needs to be prioritized. In the densely populated Western Ghats, this can only be achieved by building partnerships with local land owners and stakeholders through innovative land-use policy and incentive schemes for conservation.  相似文献   

11.
郑娇琦      王华斌  刘伟玲  张林波 《水土保持研究》2015,22(6):245-249
生态系统功能是指生态系统与生态过程所形成及所维持的人类赖以生存的自然环境条件与效用,与人类的生产生活密切相关。以RS和GIS技术为基础,利用TM遥感影像、植被NDVI以及气象等数据,计算2000—2010年辽河流域土地利用、景观格局、植被覆盖、水源涵养能力、土壤侵蚀强度以及生物多样性保护能力等指标的变化,从而分析近10 a来辽河流域生态系统基本状况以及变化趋势。结果表明:近10 a间,辽河流域城镇在一定程度上有所扩张,但并未破坏生态用地;植被覆盖度、水源涵养能力、生物多样性保护能力都有提高;土壤侵蚀强度有所增加,一定程度受2010年降水量的影响。总体来说,2000—2010年,辽河流域生态系统功能基本处于稳定且有转好的的趋势;但仍需注意城镇的扩张对耕地以及生态用地的影响。  相似文献   

12.
The future food supply of all societies depends on the exploitation of genetic recombination and allelic diversity for crop improvement, and many of the world's farmers depend directly on the harvests of the genetic diversity they sow for food and fodder as well as the next season's seed. On farm conservation is an important component of the global strategy to conserve crop genetic resources, though the structure of costs and benefits from on farm conservation differ from those associated with ex situ conservation in gene banks. A fundamental problem that affects the design of policies to encourage on farm conservation is that crop genetic diversity is an impure public good, meaning that it has both private and public economic attributes. This concept is defined and made operational in order to assist practitioners in identifying (1) least-cost sites for on farm conservation (2) the types of policy instruments that might be appropriate for supporting conservation once a site has been located. Published findings regarding prospects for on farm conservation as economies develop are summarized and empirical examples of suitable policies to support farmers' decisions are placed in the context of economics principles.  相似文献   

13.
Solid waste management arose and persists as a social problem for two fundamental reasons. First, the absorptive media for waste solids — the air, water and land — are communal resources over which private property rights cannot, and properly ought not, be defined and enforced. Secondly, the spillover effects of private waste disposal in populated areas have the inevitable result that private decisions are socially not acceptable. Both the publicness of basic resources and the spillover effects of private behavior result in the failure of the market to achieve social efficiency and optimality. A society that relies on markets to allocate resources and reconcile individual choices must have assurance that markets function to achieve social efficiency. The aim of public policy with regard to solid waste management is to correct the market mechanism so that private behavior is changed and market prices modified to reflect social costs and private preferences. This paper explores some alternative public policies available for manipulating market prices and moving the economy toward a social optimum. I contend that market interference is essential in solving the solid waste problem, but that the aim of such interference is not so much to circumvent markets as it is to utilize them for changing private behavior.  相似文献   

14.
Pasture degradation is one of the major environmental and economic problems of Brazilian livestock production. Based on the estimates of soil loss in 140,297 km2 pasturelands of Goiás State and the Federal District, the effects of land use and management and conservation practices on soil erosion by water were evaluated. Soil loss was estimated with the empirical revised universal soil loss equation model under four scenarios of land use and management of pastures and the implementation of terraces. The effects of converting hilly areas into permanently preserved areas were also evaluated. Well‐managed pastures planted in terraces and highly sloped areas with native vegetation featured a reduction of 709% in the rate of soil erosion by water in comparison with poorly managed pastures without soil conservation practices. The environmental consequences of pasture degradation become particularly important when they are associated with land use in the Amazon and Cerrado biomes because farmers in these regions are forced to open new natural areas. In addition, the high indices of bare soil in degraded pastures contribute significantly to sediment deposition in rivers and dams. The modeling of soil loss is demonstrated to be an important tool for land use planning and supporting public policies focused on the sustainable use of natural resources. The results of these simulations demonstrate the importance of actions to recover degraded pastures, such as the Federal Government's program known as ABC (Low Carbon Agriculture). Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

15.
试论将“水土保持”改称“水土生态保持”的科学性   总被引:3,自引:9,他引:3  
我国“水土保持”一词的提出已有60多年的历史,而治理水土流失的历史则可以追溯到西周初期(公元前16~11世纪)。水和土是陆地生态系统重要的生态因子,而以水和土为首要立地条件的生态植被,是陆地生态系统的第一性生产者,也是水土保持生态效益的直接承担者,所以植被的保护和恢复是水土保持不可或缺的重要部分,生态保护和生态与环境的改善愈来愈成为水土保持不可分割的重要内容。从水土保持的历史和当今不断丰富的水土保持实践来看,应将传统的“水土保持”称谓改称“水土生态保持”,这样更符合水土保持学科发展的需要,能够反映当前水土保持实践,有利于提高全社会对水土保持生态建设的认知度,有利于水土保持的行业管理。  相似文献   

16.
This study tests a rapid, user-friendly method for assessing changes in erosion risk, which yields information to aid policy development and decision-making for sustainable natural resources management. There is currently a lack of timely, up-to-date and current information to support policy development on sustainable natural resources management in Uganda. The study was carried out in the Ngenge watershed, a typical catchment in the Ugandan Highlands, characterised by deforestation in favour of subsistence agriculture without adequate soil and water conservation measures. The watershed is experiencing soil erosion, sedimentation and flooding problems which are threatening agricultural productivity and food security. Sustainable management of environmental resources is needed to ensure a livelihood for the rural population which is dependent on the land. Historical erosion risk was evaluated in three steps using multi-temporal satellite data. First, current erosion risk was assessed by combining slope and vegetation cover during periods of high intensity rainfall. The data used for the assessment was obtained from public (free) satellite images. Erosion risk was then linked to land use and finally to the change in vegetation cover over the years 1980-2000. The analysis of erosion risk using rainfall, slope and NDVI (Normalised Difference Vegetative Index) as a proxy for vegetation cover gives an indication of the current erosion risk in the area. The results of historical vegetation cover change analysis indicate an overall increase in areas under erosion risk in the study area from 1980 to 2000. This method of erosion risk mapping provides a quick and straightforward means for identifying priority areas for interventions for soil and water resource management. Considering that resources are limited, the interventions to be appropriate have to be focused mainly on areas affected by degradation.  相似文献   

17.
Scheduling conservation action is necessary when the available resources for conservation are insufficient to adequately protect all of the natural features (e.g. species, vegetation types, ecosystems) in a region, at least in the short-term. We propose an approach to scheduling conservation action in production landscapes. It is based on two characteristics of potential conservation areas. The first is vulnerability — the likelihood or imminence of destruction or alteration of native vegetation. The second is irreplaceability — the likelihood that an area will be needed to contribute to a set of conservation targets nominated for the region's features. We argue that highest priority for conservation action should go to those areas with both high vulnerability (urgent protection needed to avoid destruction) and high irreplaceability (few or no alternatives if destroyed). To establish the context and rationale for our approach, we review some previous methods for scheduling nature conservation. We then apply our approach to the Western Division of New South Wales, a region of about 325,000 km2, by deriving information on the vulnerability of 248 land systems to two threatening processes (clearing and cropping) and measuring the irreplaceability of potential conservation areas. Our results are maps of areas where conservation action is most urgently needed if regional conservation targets are not to be compromised.  相似文献   

18.
发达国家化肥减量政策的适用性分析及启示   总被引:2,自引:0,他引:2  
通过梳理和分析欧盟、美国和日本等代表性国家(地区)化肥减量政策的具体做法、实施效果和适用条件,以期发现化肥减量政策在环境取向制定时的共同规律和一般条件,从而为中国化肥减量政策的制定提供可行的政策建议。研究表明,各个国家(地区)的化肥减量政策各有优缺点且适用条件不同,其中欧盟的命令控制型政策适用于涉及农户少、农业种植类型或农场类型同一的情况,美国的经济激励型政策适用于涉及农户较多、农产品市场体制比较完善、价格形成机制灵敏的情况,日本的公众参与型政策适用于相关农业团体较多、经济实力较强的地区。因此,中国在制定化肥减量政策时,应对各国的政策手段取长补短、综合选择;为此,应从完善农产品价格机制和无公害农产品认证制度和积极培育新型农业经营主体等方面着手,通过市场机制的引导促进环境友好型技术的采纳、通过化散为整确保环境标准的有效执行、通过协同带动和宣传引导提高农民的环境意识,从而保证命令控制型、经济激励型和公众参与型等化肥减量政策的有效实施。  相似文献   

19.
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   

20.
坝上植被恢复建设分区研究   总被引:1,自引:0,他引:1  
在半干旱地区 ,水资源量是植被生态建设的主要限制因子 ,也是农牧交错区生态恢复与重建的基本依据。以河北坝上为例 ,分析了降水因子对植被分布的影响 ,结合立地条件与土地退化区域分布现状 ,参照坝上植被生态建设相关成功经验 ,探讨了坝上分区植被恢复建设方略  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号