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1.
Economic land use, ecosystem services and microfounded species dynamics   总被引:1,自引:0,他引:1  
In an integrated economy–ecosystem model humans choose their land use and leave the residual land as habitat for three species forming a food chain. The size of habitat determines the diversity and abundance of species. That biodiversity generates, in turn, a flow of ecosystem services with public-good characteristics for human consumption. The ecosystem submodel yields (rather than assumes!) population growth functions with each species’ growth depending on the size of habitat. First the relationship between habitat and species growth (sustenance, decline and extinction) is explored. The laissez-faire economy is shown to result in an underprovision of habitat making the case for land use restrictions for nature protection. The optimal land use policy is characterized with full regard of ecosystem dynamics. Finally, labor-augmenting technical change is introduced to generate ever increasing pressure towards further habitat reductions. In the laissez-faire economy the habitat is consequently squeezed to zero in the long-run so that all species are doomed. Social optimality demands, however, to refrain from using all land for economic purposes despite ever growing labor productivity.  相似文献   

2.
Simulating future land use and ecosystem services in Northern Thailand   总被引:1,自引:0,他引:1  
Enhancing ecosystem services is important as it provides foundation for the wellbeing of people. This paper presents the future land use simulation for enhancing ecosystem services using CLUMondo dynamic spatial model. The land use change was assessed from 1989 to 2013 in Wang Thong watershed of Northern Thailand using GIS and a set of ecosystem services was assessed using the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model. Future land uses until 2030 were projected for three policy scenarios, namely business-as-usual, integrated land use development, and enhancing environmental services with different levels of emphasis on ecosystem services. In business-as-usual scenario, it was observed that ecosystem services will decline by 2030 from the base year of 2013, whereas in integrated land use development scenario, the ecosystem services will increase by 5% compared to base year due to anticipated effective protection of remaining forests in all existing and proposed protected areas of the study area. In enhancing environmental services scenario, the ecosystem services will increase by 15%. Such results can serve as useful information in policy formulation in developing land use options, which help enhance ecosystem services in future.  相似文献   

3.
Concerns over the expropriation of and encroachment on indigenous communities' lands have led to greater formalization of these communities' rights in a number of developing countries. We study whether formalization of indigenous communities' land rights affects the rate of deforestation in both the short and medium terms. Beginning in 1995, the Government of Brazil formalized the rights of several hundred indigenous communities whose lands cover more than 40 million hectares in the Amazon region and provided support for these rights’ enforcement. We study the program's impacts using a long time-series of satellite-based forest cover data. Using both plausibly exogenous variation in the timing of formalization and matched samples of treated and comparison communities, we find no effect of these protections on satellite-based greenness measures. This is true even for communities that received support for surveillance and enforcement of these rights. Notably, we observe low counterfactual rates of deforestation on communities' lands between 1982 and 2010, suggesting that indigenous land rights programs should not uniformly be justified on the basis of their forest protection, at least in the medium term.  相似文献   

4.
It is important for humans to live in harmony with ecosystems. Evaluation of ecosystem services (ES) may be helpful in achieving this objective. In Japan, forest ecosystems need to be re-evaluated to prevent their degradation due to lack of forest management.In order to evaluate the effects of forest management on forest ES, we developed a process-based biogeochemical model to estimate water, carbon, and nitrogen cycles in forest ecosystems (BGC-ES). This model consists of four submodels: biomass, water cycle, carbon-nitrogen (CN) cycles, and forest management. The biomass submodel can calculate growth of forest biomass under forest managements.Several parameters of the model were calibrated using data from observations of evapotranspiration flux and quality of stream flow in forests. The model results were compared with observations of runoff water from a dam catchment site and with carbon flux observations.Our model was coupled with a basin-level GIS database of forests. Evaluations under various forest management scenarios were carried out for forests in a basin contained in the Ise Bay basin (Chubu region, Japan), where plantations (artificial forests) seemed to have degraded from poor forest management.Comparing our simulation results with those of forests without management in the basin, we found that the amounts of absorbed carbon and runoff were larger in managed forests. In addition, the volume of harvested timber was larger and its quality (diameter) was better in managed forests. Changes of ES within the various scenarios were estimated for their economic value and were compared with the cost of forest management.  相似文献   

5.
生态系统服务内涵、价值评估与GIS表达   总被引:1,自引:0,他引:1  
生态系统服务价值评估是当前生态经济学领域的研究热点,为解决生态系统之于人类的重要性提供了量化的参考,也是生态补偿机制建立的重要依据.近5年国际上SCI论文发表数量以年均40%速度增长,我国研究起步于上世纪90年代末,十年来发展迅速,从对国外研究的简单模仿逐渐转向对评估模型参数的修正及对技术方法的适应性集成与发展.生态系统服务的内涵研究不断推进,在阐释“自然组分-生态过程-生态功能-生态服务.获得利益”关系上呈现多种观点,相应地提出了不同的价值评估指标体系;生态系统服务价值评估以瞬时静态为主,动态评估略显不足;研究对象从大尺度和单一生态系统逐渐转向中尺度区域,评估结果表现形式从单一数值化向基于GIS的空间表达发展.在回顾全球范围生态系统服务评估研究成果的基础上,从研究区域分布与学科特点、内涵及分类、评估方法和GIS技术应用等四大方面进行归纳分析,并从生态系统管理和决策支持需求的角度,指出生态系统评估研究已取得显著进展,但有关生态系统服务的内涵与分类、生态系统服务价值的动态评估及GIS技术的应用研究仍待深入.  相似文献   

6.
Ecosystems are dynamic complexes. These dynamics can be described by different ecophysiological parameters and systems theoretical concepts like succession, thermodynamics, information/network theory, resilience, adaptability and the orientor concept. In this paper, different indicators and concepts are linked to Holling's adaptive cycle metaphor in order to derive hypotheses on potential system trajectories. The hypotheses focus on an exemplary temperate forest ecosystem experiencing the adaptive cycle's four phases of exploitation, conservation, collapse and reorganization after an initializing fire event. The different properties are correlated to the number of total system connections and show varying trajectories. Additionally, the provision of selected forest ecosystem services during the different phases is hypothesized and compared to three other land use types.  相似文献   

7.
Until the last decade, protecting the environment was seen as a factor contributing to human well-being, and conservation of natural ecosystems was considered to be one of the most important factors of environmental protection. Numerous studies have dealt with the benefits of natural ecosystems and in recent years even more so with ecosystem services, as well as interactions of ecosystem services with each other and with the urban and peri-urban environment. This paper suggests an approach to the spatial unity of the Florina region using basic ecosystem services identified by land use. The aim was, first, to describe the spatial distribution of basic ecosystem services and their interactions and, second, to investigate whether they form important statistical correlations with the basic features of the prefecture. A 1 km × 1 km analysis of 10 ecosystem services covering the surface of the prefecture was carried out.  相似文献   

8.
The U.S. Environmental Protection Agency uses environmental models to inform rulemaking and policy decisions at multiple spatial and temporal scales. As decision-making has moved towards integrated thinking and assessment (e.g. media, site, region, services), the increasing complexity and interdisciplinary nature of modern environmental problems has necessitated a new generation of integrated modeling technologies. Environmental modelers are now faced with the challenge of determining how data from manifold sources, types of process-based and empirical models, and hardware/software computing infrastructure can be reliably integrated and applied to protect human health and the environment.In this study, we demonstrate an Integrated Modeling Framework that allows us to predict the state of freshwater ecosystem services within and across the Albemarle-Pamlico Watershed, North Carolina and Virginia (USA). The Framework consists of three facilitating technologies: Data for Environmental Modeling automates the collection and standardization of input data; the Framework for Risk Assessment of Multimedia Environmental Systems manages the flow of information between linked models; and the Supercomputer for Model Uncertainty and Sensitivity Evaluation is a hardware and software parallel-computing interface with pre/post-processing analysis tools, including parameter estimation, uncertainty and sensitivity analysis. In this application, five environmental models are linked within the Framework to provide multimedia simulation capabilities: the Soil Water Assessment Tool predicts watershed runoff; the Watershed Mercury Model simulates mercury runoff and loading to streams; the Water quality Analysis and Simulation Program predicts water quality within the stream channel; the Habitat Suitability Index model predicts physicochemical habitat quality for individual fish species; and the Bioaccumulation and Aquatic System Simulator predicts fish growth and production, as well as exposure and bioaccumulation of toxic substances (e.g., mercury).Using this Framework, we present a baseline assessment of two freshwater ecosystem services-water quality and fisheries resources-in headwater streams throughout the Albemarle-Pamlico. A stratified random sample of 50 headwater streams is used to draw inferences about the target population of headwater streams across the region. Input data is developed for a twenty-year baseline simulation in each sampled stream using current land use and climate conditions. Monte Carlo sampling (n = 100 iterations per stream) is also used to demonstrate some of the Framework's experimental design and data analysis features. To evaluate model performance and accuracy, we compare initial (i.e., uncalibrated) model predictions (water temperature, dissolved oxygen, fish density, and methylmercury concentration within fish tissue) against empirical field data. Finally, we ‘roll-up’ the results from individual streams, to assess freshwater ecosystem services at the regional scale.  相似文献   

9.
We aimed to identify priority research questions in the field of biodiversity, ecosystem services and sustainability (BESS), based on a workshop held during the NRG BESS Conference for Early Career Researchers on BESS, and to compare these to existing horizon scanning exercises. This work highlights the need for improved data availability through collaboration and knowledge exchange, which, in turn, can support the integrated valuation and sustainable management of ecosystems in response to global change. In addition, clear connectivity among different research themes in this field further emphasizes the need to consider a wider range of topics simultaneously to ensure the sustainable management of ecosystems for human wellbeing. In contrast to other horizon scanning exercises, our focus was more interdisciplinary and more concerned with the limits of sustainability and dynamic relationships between social and ecological systems. The identified questions could provide a framework for researchers, policy makers, funding agencies and the private sector to advance knowledge in biodiversity and ES research and to develop and implement policies to enable sustainable future development.  相似文献   

10.
In the complex causation behind land change, dependent causation can play a central role. A case in point concerns land tenure diversity, where contrasting use rules for different lands may affect the impacts of other drivers on land use outcomes. We therefore evaluate the evolutionary theory of land rights (ETLR), which assumes homogeneous private property rights, in order to test for dependent causation due to distinct use rules among various types of private lands. In the present analysis, we focus on whether land tenure type modifies the effects of highway infrastructure on key outcomes highlighted in the ETLR framework. We take up the case of rural settlements along the Inter-Oceanic Highway in the eastern part of the Brazilian state of Acre, where there is considerable land tenure diversity. Findings from multivariate models for land titling, the castanha nut harvest, and cattle pasture all indicate that the effects of infrastructure depend on land tenure type. These results confirm the importance of dependent causation behind land use and bear implications for theory on land change, infrastructure impacts, and land system science.  相似文献   

11.
广东鹤山林-果-草-鱼复合生态系统生态服务功能价值评估   总被引:1,自引:0,他引:1  
戚英  虞依娜  彭少麟 《生态环境》2007,16(2):584-591
鹤山丘陵地“林-果-草-鱼”复合农林生态系统是1986年建立在退化丘陵地,利用物质与能量循环流动等生态学原理,进行构建和恢复而成功的实例,本文采用物质量和价值量相结合的评价方法,首次选取复合农林业系统进行评价,首次对广东鹤山林-果-草-鱼复合农林生态系统的生态服务功能进行价值评估。结果表明,广东鹤山林-果-草-鱼复合生态系统总体指标显著优越,其服务价值功能达2397.9783万元,在维持大气平衡、固土保肥、涵养水源等方面具有重要的作用。其间接生态服务功能价值远远大于直接生态服务功能价值,比值约为31∶1。而维持大气平衡服务价值是鹤山林-果-草-鱼复合生态系统的主要部分,占总体服务价值的96.626%,而木材生产等直接经济价值仅占总价值的3.135%。由此,直接经济价值并不是其服务价值的主要部分,应充分发挥鹤山林-果-草-鱼复合生态系统的其他生态服务功能,加强对间接生态服务功能价值的理解和保护,从长远策划和开发土地来达到长远而合理的利益收获。  相似文献   

12.
Abstract:  Ecosystem management was formally adopted over a decade ago by many U.S. natural resource agencies, including the Forest Service and the Bureau of Land Management. This approach calls for management based on stakeholder collaboration; interagency cooperation; integration of scientific, social, and economic information; preservation of ecological processes; and adaptive management. Results of previous studies indicate differences in the extent to which particular components of ecosystem management would be implemented within the U.S. Forest Service and the Bureau of Land Management and suggest a number of barriers thought to impede implementation. Drawing on survey and interview data from agency personnel and stakeholders, we compared levels of ecosystem-management implementation in the Forest Service and Bureau of Land Management and identified the most important barriers to implementation. Agency personnel perceived similarly high levels of implementation on many ecosystem-management components, whereas stakeholders perceived lower levels. Agencies were most challenged by implementation of preservation of ecological processes, adaptive management, and integration of social and economic information, whereas the most significant barriers to implementation were political, cultural, and legal.  相似文献   

13.
The seasonal variation and partition of trace metals (Fe, Cu, Zn, Mn, Cd, Cr and Pb) in the surface sediments of the Calabar River are reported. Chemical partition of the metals in the sediments reveals that 2–30% of the total metal load was contributed by the non-detrital (acid-soluble) fraction, while fine-grained host minerals/compounds are the main carriers of the detrital (acid-insoluble) fraction (70–98%). Using multivariate statistical analysis, the seasonal fluctuations in the distribution of some of the metals show significant influence by physio-chemical changes (dissolved oxygen, pH, salinity and conductivity) in the water column. Fe–Mn oxide grain coatings and sulphide materials have been identified as scavengers of some of the non-detrital and detrital trace metals in the sediments. On the basis of index of geoaccumulation (I-geo) and comparison with previous studies, the Calabar River surface sediments have been classified as unpolluted.  相似文献   

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