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1.
A Systems Approach to Biodiversity Conservation Planning   总被引:1,自引:0,他引:1  
With a recent media-fueled transition from a scientific to a political perspective, biodiversity has become an issue of ethics and ensuing values, beyond its traditional ecological roots. More fundamentally, the traditional perspective of biodiversity is being challenged by the emergence of a post-normal or systems-based approach to science. A systems-based perspective of living systems rests on the central tenets of complexity and uncertainty, and necessitates flexibility, anticipation and adaptation rather than prediction and control in conservation planning and management. What are the implications of this new perspective? This paper examines these challenges in the context of biodiversity conservation planning. The new perspectives of biodiversity are identified and explored, and the emergence of a new ecological context for biodiversity conservation is discussed. From the analysis, the challenges and implications for conservation planning are considered, and a systems-based or post-normal approach to conservation planning and management is proposed. In light of the new perspectives for biodiversity, conservation planning and management approaches should ultimately reflect the essence of living systems: they should be diverse, adaptive, and self-organizing, accepting the ecological realities of change.  相似文献   

2.
It is generally accepted that for many species, the ability to get around a reserve promotes their long-term persistence. Here, we measure the ease with which species can move by two spatial criteria: (i) the connectivity of the reserve, that is to say, the possibility to go through the whole reserve without leaving it, and (ii) the compactness of the reserve, that is to say, the remoteness of the sites in relation to each other, the distance between two sites being measured by the shortest distance to travel to get from one site to another without leaving the reserve. To protect the reserve of external disturbances, we also impose a connectivity constraint for the area outside the reserve. This article presents a method based on integer linear programming to define connected and compact reserves. Computational experiments carried out on artificial instances with 400 sites and 100 species are presented to illustrate the effectiveness of the approach.  相似文献   

3.
This study explores ecological vulnerability to land-use change in the U.S. Mid-Atlantic Region by spatially extrapolating land and economic development, and overlaying these projections with maps of sensitive ecological resources. As individual extrapolations have a high degree of uncertainty, five methods with different theoretical bases are employed. Confidence in projections is increased for counties targeted by two or more projection methods. A county is considered at risk if it currently supports three or more sensitive resources, and is projected to experience significant growth by the year 2010 by two or more methods. Analysis designated 19 counties and two cities as at risk, highlighting within a large region the priority areas where state and regional efforts would contribute the most to integrating environmental considerations into the process of land development. The study also found that potentially severe ecological effects of future land-use change are not limited to the outskirts of major urban areas. Recreational demands on smaller communities with mountain and coastal resources are also significant, as are initiatives to promote economic development in rural areas of high ecological quality. This approach provides a comprehensive overview of potential regional development, leading to an objective prioritization of high-risk areas. The intent is to inform local planning and decision-making so that regional and cumulative ecological degradation are minimized.  相似文献   

4.
We study Markovian models for population processes in continuous time, addressing questions concerning the behaviour of ensembles of individuals (equilibrium, quasi-equilibrium and time-dependent behaviour) and, in particular, what can be deduced from models for individual behaviour.  相似文献   

5.
This paper presents the design, development and implementation of an integrated GIS-controlled knowledge-based system for environmental monitoring applications, utilizing indigenous flora for assessing quality. The system gathers and combines geographical, ecological, and physicochemical data of organisms' response to pollution within an intelligent computer program that (a) recognises groups of indigenous species suitable for long-term monitoring of a specific pollutant or a combination of pollutants, (b) estimates the ambient concentration of pollutant(s) from the population of the species comprising the bioindicator group and (c) provides biomonitoring capacity indices at national and international/transboundary levels. Significantly, a novel system in the form of a rational framework at the conceptual design level has been developed, that actually contributes towards achieving a cost-effective long-term biomonitoring program, with the flexibility to counter on-course any (anticipated or not) variations/modifications of the surveillance environment: the scheme assumes a robust dynamic cooperation between instrumental and biomonitoring systems, with a view to minimise uncertainty and monitoring costs and increase reliability of pollution control and abatement, aiming eventually at the shifting, partially or totally, from instrumental to natural monitoring. The proposed approach is presently implemented at pilot-scale for establishing a biomonitoring network at a large industrial area in Greece. The results obtained indicate that a cost-effective program can be only attained and maintained under a suitable financial/organizational scheme at the macro level, whereas the micro level viability strongly depends upon careful management of human resources and fixed assets.  相似文献   

6.
基于RSEI模型的祁连山自然保护区生态环境质量评价   总被引:2,自引:0,他引:2  
基于1988-2018年祁连山国家自然保护区的Landsat系列遥感影像,利用绿度、湿度、热度和干度指标计算获得遥感生态指数(RSEI),并应用RSEI对保护区近30年的生态环境质量作评价.结果表明:近30年来该保护区生态环境质量整体呈好转趋势,RSEI上升0.016,可1998-2018年生态环境质量有所下降;生态环...  相似文献   

7.
The U. S. Environmental Protection Agency's Office of Research and Development (ORD) is continuing research efforts initiated by the Environmental Monitoring and Assessment Program on ecological indicator development. An ORD Ecological Indicators Working Group has been formed with activities in three primary areas. (1) Guidelines and procedures are being developed to evaluate indicators for use in monitoring programs. Indicators will be evaluated on conceptual soundness, implementation, response variability, and interpretation/utility. The evaluation guidelines will be applied in peer review to endorse technically acceptable indicators and will provide research direction for improvements. (2) An ORD strategy for research in ecological indicators is being developed by the Working Group in collaboration with Division research scientists. The strategy will serve to prioritize research based on the greatest importance and uncertainty and identify goals for indicator development in both intramural and extramural programs. The research strategy includes application of the evaluation guidelines to identify relevant research questions. (3) Interactions with indicator client and user groups (states, program offices and regions) are actively being sought for successful development and implementation of indicators. Client indicator priorities are formally included in the research strategy and user feedback on indicators will help to identify relevant research questions. Consultations with users will serve to assist in evaluating, implementing, and interpreting indicators in monitoring programs.  相似文献   

8.
We develop a reserve design strategy to maximize the probability of species persistence predicted by a stochastic, individual-based, metapopulation model. Because the population model does not fit exact optimization procedures, our strategy involves deriving promising solutions from theory, obtaining promising solutions from a simulation optimization heuristic, and determining the best of the promising solutions using a multiple-comparison statistical test. We use the strategy to address a problem of allocating limited resources to new and existing reserves. The best reserve design depends on emigration, dispersal mortality, and probabilities of movement between reserves. When movement probabilities are symmetric, the best design is to expand a subset of reserves to equal size to exhaust the habitat budget. When movement probabilities are not symmetric, the best design does not expand reserves to equal size and is strongly affected by movement probabilities and emigration rates. We use commercial simulation software to obtain our results.  相似文献   

9.
The Ecosystem Management Decision Support (EMDS) system is an application framework for knowledge-based decision support of ecological assessments. EMDS integrates geographic information system and knowledge base system technologies to provide an analytical tool for environmental assessment and monitoring. The basic objective of EMDS is to improve the quality and completeness of environmental assessments and the efficiency with which they are performed. The USDA Forest Service and the U.S. Environmental Protection Agency have cooperatively developed an EMDS knowledge base for watershed condition assessment. Specifically, this knowledge base evaluates watershed processes, patterns, general effects of human activity, and fisheries habitat suitability. Such assessments are based on spatially explicit input data concerning current conditions and reference conditions which are subsequently interpreted by user-defined "fuzzy" membership functions. In this paper we describe basic components of our knowledge base for assessing watershed condition and illustrate its application within northern Idaho and northwestern Montana.  相似文献   

10.
A graphical heuristic was devised for locating upgradient groundwater monitoring wells near landfills. Utilizing computer-simulated contaminant plumes, the heuristic considers the direction of groundwater flow relative to the shape of a landfill, the location of the downgradient migration boundary used for configuring detection wells, and uniformity of spatial coverage. The heuristic positions upgradient wells far enough from a landfill to avoid contamination, but close enough to measure ambient water quality near the landfill. It can be adapted to nonuniform flow fields, nonlinear migration boundaries, and irregularly shaped landfills. An application to a rectangular landfill, oriented at various angles to the direction of groundwater flow, demonstrates the utility of the approach.  相似文献   

11.
Conservation planners are called upon to make choices and trade-offs about the preservation of natural areas for the protection of species in the face of development pressures. We addressed the problem of selecting sites for protection over time with the objective of maximizing species representation, with uncertainty about future site development, and with periodic constraints on the number of sites that can be selected. We developed a 0–1, linear optimization model with 2 periods to select the sites that maximize expected species coverage subject to budget constraints. The model is based on the idea that development uncertainty can be characterized by a set of scenarios, each of which is a possible second-period development outcome for the set of sites. We also suggest that our 2-period model can be used in a sequential fashion that is consistent with adaptive planning. Results are presented for the Fox River watershed in Chicago.  相似文献   

12.
Conservation planners are called upon to make choices and trade-offs about the preservation of natural areas for the protection of species in the face of development pressures. We addressed the problem of selecting sites for protection over time with the objective of maximizing species representation, with uncertainty about future site development, and with periodic constraints on the number of sites that can be selected. We developed a 0–1, linear optimization model with 2 periods to select the sites that maximize expected species coverage subject to budget constraints. The model is based on the idea that development uncertainty can be characterized by a set of scenarios, each of which is a possible second-period development outcome for the set of sites. We also suggest that our 2-period model can be used in a sequential fashion that is consistent with adaptive planning. Results are presented for the Fox River watershed in Chicago.  相似文献   

13.
Indoor radon concentrations depend on building characteristics such as building materials, ventilation and water supply. In this paper, a quantile regression approach is proposed to evaluate the effect of some buildings factors potentially influencing indoor radon concentration. Many of the considered factors, such as soil connection, age of construction and being a single family building, are found to have a statistically significant effect; however, this is far from being constant across the entire support of indoor radon concentration. A potential impact due to geological and geo-physical reasons is also found using the altitude of building locations as a surrogate variable. In addition, a clear local spatial effect is detected by a spatial autoregression approach.  相似文献   

14.
A fuzzy logic approach has been developed to assess the groundwater pollution levels below agricultural fields. The data collected for Kumluca Plain of Turkey have been utilized to develop the approach. The plain is known with its intensive agricultural activities, which imply excessive application of fertilizers. The characteristics of the soils and underlying groundwater for this plain were monitored during the years 1999 and 2000. Additionally, an extensive field survey related to the types and yields of crops, fertilizer application and irrigation water was carried out. Both the soil and groundwater have exhibited high levels of nitrogen, phosphorus and salinity with considerable spatial and temporal variations. The pollution level of groundwater at several established stations within the plain were assessed using Fuzzy Logic. Water Pollution Index (WPI) values are calculated by Fuzzy Logic utilizing the most significant groundwater pollutants in the area namely nitrite, nitrate and orthophosphate together with the groundwater vulnerability to pollution. The results of the calculated WPI and the monitoring study have yielded good agreement. WPI indicated high to moderate water pollution levels at Kumluca plain depending on factors such as agricultural age, depth to groundwater, soil characteristics and vulnerability of groundwater to pollution. Fuzzy Logic approach has shown to be a practical, simple and useful tool to assess groundwater pollution levels.  相似文献   

15.
Ecological Land Classification (ELC) is a scientific endeavour which attempts to organize, stratify and evaluate ecosystems (and complexes of ecosystems) for the purposes of land resource management. Since ecosystems themselves are not easily defined in practical terms, ELC is likewise not a trivial concept. Nonetheless, ELC is a prerequisite for ecosystem management and the conservation of biological diversity simply because ecosystems must be described, characterized and spatially-located before they can be managed. Regarding the current status and future direction of ELC, mainly in relation to forest management: 1) approaches to ELC construction and utilization have shifted considerably over the past 2 decades; 2) there appears to be a current consensus regarding basic approaches to ELC; 3) spatial scale is a critical variable that must be addressed by ELCs; 4) ELCs must strive to more directly address management objectives; 5) natural ecosystem functions need to be better integrated within ELC frameworks; and, 6) the need for quality, georeferenced ELC-related data will continue to grow.  相似文献   

16.
Ecological regionalization according to the USDA Forest Service National Hierarchical Framework of Ecological Units was undertaken for the New England-New York region. A topdown, map-overlay approach was used to map sections and subsections. Where available, landscape level units (LTAs) were aggregated and evaluated to supplement the subsection mapping. A regional collaborative effort was undertaken to counterbalance the shortfalls of a purely mechanistic approach. As a result of this process, 17 section and 58 draft subsection units were delineated for the New England-New York region. The sub-regional units developed reflect the strong correspondence among climate, topography and geography at this scale. Geologic factors, due to their influence on landform and mineral availability, are also reflected in the ecological unit boundaries. Efforts to apply the multifactor model at the sub-regional level have been hampered by the lack of scale appropriate information on a number of factors particularly meso-scale climate and potential natural community composition and distribution. Further research and investigation are required before these criterion are adequately met.  相似文献   

17.
针对中国目前环境应急资源储备体系不成熟的现状,从制度建设、人力保障、物资及装备配置、信息平台构建等方面,提出了储备体系的构建方案,为中国建立科学的环境应急资源储备体系、提高环境应急处置能力提供重要指导。同时,就中国环境应急救援体系现存问题,提出了制定环境应急法、信息共享、救援队伍整合等具体的完善建议。  相似文献   

18.
The results of a biodiversity monitoring program conducted in the Ogawa Forest Reserve and its vicinity, situated in a cool temperate region of Japan, identified three different patterns for species richness. Forests of the region are characterized by a mosaic of secondary deciduous stands of various ages scattered among plantations of conifers. The three different types of change in species richness observed in response to the stand age are as follows: Type I (butterflies, tube-renting bees and wasps, hoverflies, fruit flies, and longicorn beetles), the species diversity was highest in open areas, just after clear-cutting, decreasing with the stand age; Type II (mushrooms and mites associated with them), older stands showed greater diversity than younger stands; and, Type III (moths, oribatid mites, collembolas, carabid beetles, and ants), the number of species did not change greatly with the stand age, though ordination analysis revealed that there was variation in species compositions. These results indicate that combinations of stands of different ages, or heterogeneously arranged stands, can contribute to the maintenance of insect biodiversity at the landscape level.  相似文献   

19.
An understanding of the behavior of the groundwater body and its long-term trends are essential for making any management decision in a given watershed. Geostatistical methods can effectively be used to derive the long-term trends of the groundwater body. Here an attempt has been made to find out the long-term trends of the water table fluctuations of a river basin through a time series approach. The method was found to be useful for demarcating the zones of discharge and of recharge of an aquifer. The recharge of the aquifer is attributed to the return flow from applied irrigation. In the study area, farmers mainly depend on borewells for water and water is pumped from the deep aquifer indiscriminately. The recharge of the shallow aquifer implies excessive pumping of the deep aquifer. Necessary steps have to be taken immediately at appropriate levels to control the irrational pumping of deep aquifer groundwater, which is needed as a future water source. The study emphasizes the use of geostatistics for the better management of water resources and sustainable development of the area.  相似文献   

20.
The development of major linear infrastructures contributes to landscape fragmentation and impacts natural habitats and biodiversity in various ways. To anticipate and minimize such impacts, landscape planning needs to be capable of effective strategic environmental assessment (SEA) and of supporting environmental impact assessment (EIA) decisions. To this end, species distribution models (SDMs) are an effective way of making predictive maps of the presence of a given species. In this paper, we propose to combine SDMs and graph-based representation of landscape networks to integrate the potential long-distance effect of infrastructures on species distribution. A diachronic approach, comparing distribution before and after the linear infrastructure is constructed, leads to the design of a species distribution assessment (SDA), taking into account population isolation. The SDA makes it possible (1) to estimate the local variation in probability of presence and (2) to characterize the impact of the infrastructure in terms of global variation in presence and of distance of disturbance. The method is illustrated by assessing the impact of the construction of a high-speed railway line on the distribution of several virtual species in Franche-Comté (France). The study shows the capacity of the SDA to characterize the impact of a linear infrastructure either as a research concern or as a spatial planning challenge. SDAs could be helpful in deciding among several scenarios for linear infrastructure routes or for the location of mitigation measures.  相似文献   

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