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1.
This paper presents a spatially explicit trade-off analysis of species conservation in agricultural areas. A spatially explicit model is presented that integrates an applied metapopulation model with a farm management model. The model is used to calculate production possibilities frontiers of net monetary benefits from agriculture and conservation of three species with different habitats. Simulations of spatial habitat allocation under European agri-environment schemes are compared to these production possibilities frontiers. The results suggest that the cost-effectiveness of current conservation policies may be greatly enhanced if the spatial dimension is considered explicitly.  相似文献   

2.
Marine protected areas are not established in an institutional and governance vacuum and managers should pay attention to the wider social–ecological system in which they are immersed. This article examines Islas Choros-Damas Marine Reserve, a small marine protected area located in a highly productive and biologically diverse coastal marine ecosystem in northern Chile, and the interactions between human, institutional, and ecological dimensions beyond those existing within its boundaries. Through documents analysis, surveys, and interviews, we described marine reserve implementation (governing system) and the social and natural ecosystem-to-be-governed. We analyzed the interactions and the connections between the marine reserve and other spatially explicit conservation and/or management measures existing in the area and influencing management outcomes and governance. A top-down approach with poor stakeholder involvement characterized the implementation process. The marine reserve is highly connected with other spatially explicit measures and with a wider social–ecological system through various ecological processes and socio-economic interactions. Current institutional interactions with positive effects on the management and governance are scarce, although several potential interactions may be developed. For the study area, any management action must recognize interferences from outside conditions and consider some of them (e.g., ecotourism management) as cross-cutting actions for the entire social–ecological system. We consider that institutional interactions and the development of social networks are opportunities to any collective effort aiming to improve governance of Islas Choros-Damas marine reserve. Communication of connections and interactions between marine protected areas and the wider social–ecological system (as described in this study) is proposed as a strategy to improve stakeholder participation in Chilean marine protected areas.  相似文献   

3.
We present conceptual and quantitative models that predict changes in fertilizer‐derived nitrogen delivery from rowcrop landscapes caused by agricultural conservation efforts implemented to reduce nutrient inputs and transport and increase nutrient retention in the landscape. To evaluate the relative importance of changes in the sources, transport, and sinks of fertilizer‐derived nitrogen across a region, we use the spatially explicit SPAtially Referenced Regression On Watershed attributes watershed model to map the distribution, at the small watershed scale within the Upper Mississippi‐Ohio River Basin (UMORB), of: (1) fertilizer inputs; (2) nutrient attenuation during delivery of those inputs to the UMORB outlet; and (3) nitrogen export from the UMORB outlet. Comparing these spatial distributions suggests that the amount of fertilizer input and degree of nutrient attenuation are both important in determining the extent of nitrogen export. From a management perspective, this means that agricultural conservation efforts to reduce nitrogen export would benefit by: (1) expanding their focus to include activities that restore and enhance nutrient processing in these highly altered landscapes; and (2) targeting specific types of best management practices to watersheds where they will be most valuable. Doing so successfully may result in a shift in current approaches to conservation planning, outreach, and funding.  相似文献   

4.
Data needed for informed conservation prioritization are generally greater than the data available, and surrogates are often used. Although the need to anticipate threats is recognized, the effectiveness of surrogates for predicting habitat loss (or vulnerability) to land-use change is seldom tested. Here, we compared properties of two different vulnerability surrogates to validated vulnerability—validated prediction of habitat conversion based on a recent assessment of land-use change. We found that neither surrogate was a particularly effective predictor of vulnerability. Importantly, both surrogates performed poorly in places most imminently threatened with habitat conversion. We also show that the majority of areas protected over the last two decades have low vulnerability to the most active threatening process in this biome (habitat conversion). The contrary patterns of vulnerability and protection suggest that use of validated vulnerability would help to clarify protection needs, which might lead to the improvement of conservation decisions. Our study suggests the integration of validated vulnerability into conservation planning tools may be an important requirement for effective conservation planning in rapidly changing landscapes. We apply our results to discuss the practical considerations and potential value of incorporating validated vulnerability into conservation planning tools both generally and in the context of New Zealand’s indigenous grasslands.  相似文献   

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We present here a method to integrate geologic, topographic, and land-cover data in a geographic information system to provide a fine-scale, spatially explicit prediction of sediment yield to support management applications. The method is fundamentally qualitative but can be quantified using preexisting sediment-yield data, where available, to verify predictions using other independent data sets. In the 674-km2 Sespe Creek watershed of southern California, 30 unique “geomorphic landscape units” (GLUs, defined by relatively homogenous areas of geology, hillslope gradient, and land cover) provide a framework for discriminating relative rates of sediment yield across this landscape. Field observations define three broad groupings of GLUs that are well-associated with types, relative magnitudes, and rates of erosion processes. These relative rates were then quantified using sediment-removal data from nearby debris basins, which allow relatively low-precision but robust calculations of both local and whole-watershed sediment yields, based on the key assumption that minimal sediment storage throughout most of the watershed supports near-equivalency of long-term rates of hillslope sediment production and watershed sediment yield. The accuracy of these calculations can be independently assessed using geologically inferred uplift rates and integrated suspended sediment measurements from mainstem Sespe Creek, which indicate watershed-averaged erosion rates between about 0.6–1.0 mm year?1 and corresponding sediment yields of about 2 × 103 t km?2 year?1. A spatially explicit representation of sediment production is particularly useful in a region where wildfires, rapid urban development, and the downstream delivery of upstream sediment loads are critical drivers of both geomorphic processes and land-use management.  相似文献   

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Measuring the economic value of environmental quality is useful to evaluate policies that affect the use of natural resources. This paper presents the findings of a contingent valuation (CV) survey designed to measure non-use values for the natural coastal environment.This was attempted through evaluating public and scientific values of conservation quality. The results suggest that public perceptions of conservation quality are multidimensional,and that it may be difficult for some individuals to express their preferences for the conservation value of natural resources in monetary terms. Additionally, public and scientific judgments differ concerning some of the physical attributes imparting conservation value. These findings have important implications on efforts to consider environmental quality in land and coastal use decisions.  相似文献   

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野大豆的资源价值及其栽培技术   总被引:4,自引:0,他引:4  
对野大豆的形态习性、资源价值以及栽培技术进行了较为详细的综述,这对保护和合理开发这一濒危野生种质资源,实现生态效益和经济效益的统一具有重要意义。  相似文献   

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Representative Landscapes in the Forested Area of Canada   总被引:1,自引:0,他引:1  
Canada is a large nation with forested ecosystems that occupy over 60% of the national land base, and knowledge of the patterns of Canada’s land cover is important to proper environmental management of this vast resource. To this end, a circa 2000 Landsat-derived land cover map of the forested ecosystems of Canada has created a new window into understanding the composition and configuration of land cover patterns in forested Canada. Strategies for summarizing such large expanses of land cover are increasingly important, as land managers work to study and preserve distinctive areas, as well as to identify representative examples of current land-cover and land-use assemblages. Meanwhile, the development of extremely efficient clustering algorithms has become increasingly important in the world of computer science, in which billions of pieces of information on the internet are continually sifted for meaning for a vast variety of applications. One recently developed clustering algorithm quickly groups large numbers of items of any type in a given data set while simultaneously selecting a representative—or “exemplar”—from each cluster. In this context, the availability of both advanced data processing methods and a nationally available set of landscape metrics presents an opportunity to identify sets of representative landscapes to better understand landscape pattern, variation, and distribution across the forested area of Canada. In this research, we first identify and provide context for a small, interpretable set of exemplar landscapes that objectively represent land cover in each of Canada’s ten forested ecozones. Then, we demonstrate how this approach can be used to identify flagship and satellite long-term study areas inside and outside protected areas in the province of Ontario. These applications aid our understanding of Canada’s forest while augmenting its management toolbox, and may signal a broad range of applications for this versatile approach.  相似文献   

14.
The Threatened Species Conservation (TSC) Act, introduced in 1995, represents a significant attempt to conserve and restore biodiversity within the state of New South Wales, Australia. This Act aims to integrate land use planning and environmental impact assessment legislation by placing increased responsibility on applicants, proponents, consent and determining authorities, and the New South Wales National Parks and Wildlife Service, in the fields of environmental planning, development control and biodiversity conservation. The TSC Act introduced a set of eight factors which have to be considered by decision makers in determining whether a development is likely to have a significant effect upon threatened species, populations, ecological communities or their habitats (the threatened biota) as listed in the Act. These eight factors are commonly referred to as the 'eight-part test'. Fifty environmental impact statements (EISs) containing eight-part tests for development proposals were obtained. The adequacy of scoping and survey exercises, the number of species identified and afforded the eight-part test, and the actual responses to each of the eight factors contained within the test, using a series of criteria, were ascertained. Sixty per cent provided an adequate scoping exercise; 6% of the surveys for flora species, and none for fauna species carried out, were adequate in terms of identifying all threatened species on the development site. Seven hundred and thirty-seven species listed in the Act were identified, 36% of which were omitted from the eight-part test procedure. The eight sections of the eight-part test were completed to a varying degree of adequacy, with none of the EISs completing all eight sections satisfactorily. Both section 4 (regarding the impacts of a development in terms of habitat isolation) and section 8 (regarding the distribution of species potentially affected by a development) were inadequately completed in all 50 EISs.  相似文献   

15.
Increasing oil transportation and severe oil accidents in the past have led to the development of various sensitivity maps in different countries all over the world. Often, however, the areas presented on the maps are far too large to be safeguarded with the available oil combating equipment and prioritization is required to decide which areas must be safeguarded. While oil booms can be applied to safeguard populations from a drifting oil slick, decision making on the spatial allocation of oil combating capacity is extremely difficult due to the lack of time, resources and knowledge. Since the operational decision makers usually are not ecologists, a useful decision support tool including ecological knowledge must be readily comprehensible and easy to use. We present an index-based method that can be used to make decisions concerning which populations of natural organisms should primarily be safeguarded from a floating oil slick with oil booms. The indices take into account the relative exposure, mortality and recovery potential of populations, the conservation value of species and populations, and the effectiveness of oil booms to safeguard different species. The method has been implemented in a mapping software that can be used in the Gulf of Finland (Baltic Sea) for operational oil combating. It could also be utilized in other similar conservation decisions where species with varying vulnerability, conservational value, and benefits received from the management actions need to be prioritized.  相似文献   

16.
菹草的经济价值及其栽培与养鱼技术   总被引:12,自引:0,他引:12  
菹草是渔业水域生态系统中的初级生产者,为渔业生产的重要自然资源之一、根据近年来的试验研究成果,本文探讨了菹草的自明、药用、饲用价值及其在渔业水域中对自然国类资原的增殖与保护作用,介绍了菹草人工栽培与养鱼的技术措施。  相似文献   

17.
在分析北京市生态涵养区在生态补偿制度建设困境的基础上,本文将国内外区域生态系统价值评估模型相结合,运用修正的生态服务价值评估模型,对北京市生态涵养区2016年的生态服务价值进行了估算,并分析了2009-2016年生态服务价值的变动及其影响因素,从科学评估生态服务价值、完善生态补偿标准方法的制定、健全生态保护补偿制度、将绿色GDP纳入生态涵养区绩效考核指标评价体系几个方面探讨了完善生态补偿机制的政策措施。一方面更加直观地揭示了生态涵养区生态服务的重要经济价值,另一方面为建立更加科学的生态补偿机制提供了可参考的依据。  相似文献   

18.
We compared measures of ecosystem state across six adjacent land-tenure groups in the intact tropical savanna landscapes of northern Australia. Tenure groups include two managed by Aboriginal owners, two national parks, a cluster of pastoral leases, and a military training area. This information is of relevance to the debate about the role of indigenous lands in the Australian conservation estate. The timing and frequency of fire was determined by satellite imagery; the biomass and composition of the herb-layer and the abundance of large feral herbivores by field surveys; and weediness by analysis of a Herbarium database. European tenures varied greatly in fire frequencies but were consistently burnt earlier in the dry season than the two Aboriginal tenures, the latter having intermediate fire frequencies. Weeds were more frequent in the European tenures, whilst feral animals were most abundant in the Aboriginal tenures. This variation strongly implies a signature of current management and/or recent environmental history. We identify indices suitable for monitoring of management outcomes in an extensive and sparsely populated landscape. Aboriginal land offers a unique opportunity for the conservation of biodiversity through the maintenance of traditional fire regimes. However, without financial support, traditional practices may prove unsustainable both economically and because exotic weeds and feral animals will alter fire regimes. An additional return on investment in Aboriginal land management is likely to be improved livelihoods and health outcomes for these disadvantaged communities.  相似文献   

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亚硝化控制技术的研究现状与动向   总被引:4,自引:0,他引:4  
本文依据可持续污水处理概念,综述了当前实现亚硝化控制技术的研究现状,分析了存在的问题,并介绍了该领域的研究动向。  相似文献   

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