GIS支持下北京市海淀区生境服务制图研究

定量化识别生境服务的空间分布是城市生物多样性保护的前提。论文从生境斑块质量和生境格局两方面构建了生境服务的量化指标及其方法框架,并基于遥感影像解译和实地调研数据利用GIS工具对北京市海淀区进行了生境服务制图研究。结果显示,生境服务供给能力最高值主要分布于海淀区西部山区和中部圆明园、颐和园一带以及北部翠湖湿地附近的零星区域,占全区总面积的16.54%。海淀区北部农村地区的绿色基础设施区域生境服务供给能力次之,分散分布于西部山前地带及北部农村村庄外围的人工林地和园地区域,占全区总面积的32.44%。海淀区南部城区及中部城乡交错区的生境服务供给能力最低,占全区总面积的24.68%。海淀区大部分农村居民点所提供的生境服务也较弱,占全区总面积的26.34%。生境服务制图结果可以为城市生物多样性保护决策制定提供一个定量化且直观形象的参考依据。

生境维持服务供给量与需求量研究——以京津冀地区为例

为衡量京津冀地区各行政区的生境维持服务责任与权益,提出以生境适宜性表征供给量,以人类开发建设导致的生境占用以及人类行为辐射导致的生境质量下降表征需求量的方法,计算京津冀地区2000,2008和2013年的生境维持服务供给量和需求量。研究表明,京津冀地区生境维持服务供给量整体上呈现自北向南逐渐减少的趋势,2000—2013年京津冀地区的开发建设需求量呈现增加的趋势,行为辐射需求量呈现下降趋势。承德市和张家口市的供给量远大于需求量,京津冀东南部沿海城市的供给量小于需求量。研究结果与京津冀地区各行政区的生态功能定位和经济发展状况基本上相符,验证了计算方法的合理性。

Influence of Cooperatives’Socialized Services on Agricultural Households’Chemical Fertilizer and Pesticide Use Intensity-Based on the Evidence from Two Counties,Hubei,China

Abuse of chemical fertilizer and pesticide will not only impair the quality of agricultural products,but also damage the agricultural ecological environment.From the perspective of cooperatives’socialized services,this paper studies agricultural households’chemical fertilizer and pesticide use behavior,attempting to provide references for the government’s formulation of relevant policies and cooperatives’adjustment of their operation strategies.The survey data of 518 agricultural households in Zigui County and Badong County,Hubei Province,China are used to examine the influence of cooperatives and their socialized services on agricultural households’chemical fertilizer and pesticide use intensity via propensity score matching.Research reveals that:(1)Joining cooperatives has a significantly negative influence on agricultural households’chemical fertilizer and pesticide use intensity,and the average treatment effect is-341.505 yuan mu^(-1).(2)Agricultural materials supply services and technical support services can significantly bring down agricultural households’chemical fertilizer and pesticide use intensity,and the average treatment effect is-225.966 yuan mu^(-1)and-163.580 yuan mu^(-1),respectively.While the influence of agricultural products sale services on chemical fertilizer and pesticide use intensity is not significant.(3)Grouped investigation is carried out by age,education years and planting scale,and the influence of socialized services on agricultural householders’chemical fertilizer and pesticide use intensity is obviously varied among different groups.The influence of agricultural materials supply services on agricultural households who are elder,with smaller education years and small planting scale is significant;the influence of technical support services on agricultural households who are younger,with higher education years and small planting scale is significant;the influence of agricultural products sale services on agricultural households who are elder is significant.It is necessary to improve the percentage of agricultural households joining cooperatives,increase the supply level of cooperatives’socialized services,and make socialized services of cooperatives more targeted.All this can contribute to further reduction of agricultural households’chemical fertilizer and pesticide use intensity.

基于InVEST模型的泉州市生态环境质量生态系统服务功能时空变化分析

为了更好地监测和保护生态环境质量(以下简称“生境质量”),本文以泉州市为研究对象,利用InVEST模型分析了生境质量服务功能的时空变化,结合ArcGIS 10.0空间分析模块的重分类工具按生态系统服务功能分级标准,将生境质量服务功能区域划分为4个等级。结果表明:生境质量状况由东南向西北方向逐渐改善。生境质量服务功能一般重要、中等重要、重要和极重要区域的面积分别占总面积的13.47%、1.84%、79.36%和5.33%。通过评估和分析生境质量的时空变化,旨在为泉州市生境质量服务功能的维护和监管提供科学依据。

A Coverage-Aware Unequal Clustering Protocol with Load Separation for Ambient Assisted Living Based on Wireless Sensor Networks

Ambient Assisted Living(AAL) is becoming an important research field. Many technologies have emerged related with pervasive computing vision, which can give support for AAL. One of the most reliable approaches is based on wireless sensor networks(WSNs). In this paper, we propose a coverage-aware unequal clustering protocol with load separation(CUCPLS) for data gathering of AAL applications based on WSNs. Firstly, the coverage overlap factor for nodes is introduced that accounts for the degree of target nodes covered. In addition, to balance the intra-cluster and inter-cluster energy consumptions, different competition radiuses of CHs are computed theoretically in different rings, and smaller clusters are formed near the sink. Moreover, two CHs are selected in each cluster for load separation to alleviate the substantial energy consumption difference between a single CH and its member nodes. Furthermore, a backoff waiting time is adopted during the selection of the two CHs to reduce the number of control messages employed. Simulation results demonstrate that the CUCPLS not only can achieve better coverage performance, but also balance the energy consumption of a network and prolong network lifetime.

Joint Occurrence Period of Wind Speed and Wave Height Based on Both Service Term and Risk Probability

Return periods calculated for different environmental conditions are key parameters for ocean platform design.Many codes for offshore structure design give no consideration about the correlativity among multi-loads and over-estimate design values.This frequently leads to not only higher investment but also distortion of structural reliability analysis.The definition of design return period in existing codes and industry criteria in China are summarized.Then joint return periods of different ocean environmental parameters are determined from the view of service term and danger risk.Based on a bivariate equivalent maximum entropy distribution,joint design parameters are estimated for the concomitant wave height and wind speed at a site in the Bohai Sea.The calculated results show that even if the return period of each environmental factor,such as wave height or wind speed,is small,their combinations can lead to larger joint return periods.Proper design criteria for joint return period associated with concomitant environmental conditions will reduce structural size and lead to lower investment of ocean platforms for the exploitation of marginal oil field.

Implementing a Rainwater Sustainable Control in SaheI-Feedback from ＂Niayes＂ Zone of Dakar

Dakar area landscape is mainly characterized by the existence of the ＂niaye＂-or agricultural depressions located in the sand dunes system. In these depressions, the top-table of quaternary sand groundwater reaches or overflows the soil surface. Because of a recent groundwater level drop, some of the niayes have become runoff-gathering sites. This water ensures various economical, environmental and social services, i.e. urban agriculture, drinking water supply of Dakar and formation of ecosystems supporting biodiversity. Given that rainwater infiltration is the only natural ＂input＂, conception and implemention of rainwater management PPP （Politics, Plan and Program） must necessarily take into account this interrelationl Nowadays, two acute problems are observed in the Dakar area. On the one hand, the niayes are threatened by a hydrological drying process due to the insufficiency of rainwater refill. On the other hand, the dramatic social pressure on the environment has led to the urbanization of these bottom-lands. Furthermore, because of the pluviometry decrease, a worsening of the nuisances （floods and malaria） related to surface waters occurs. Consequently, an appropriate runoff management should integrate both the ＂risk＂ and ＂resource＂ dimensions, thus allowing the protection of natural resources and a secure living environment. According to the limits of＂classicai＂ solutions, this paper provides approach elements for building a sustainability plan focusing on emergent concerns, which would control rainwater in urbanized zones.

Payment for Ecosystem Services Markets and Rural Development in BrazilmA Co-evolutionary Approach

The article discusses the payment for ecosystem or environmental services markets in Brazil with a critical review, based on the ecological economics literature and focused on the concept of co-evolution. It is argued that the mainstream approach which considers ecosystem services as an externality has many shortcomings and fails to consider institutional and political aspects---all very critical for the design and implementation of a PES （Payment for ecosystem services） project or program. The complexity and the diversity of co-evolutionary relations between ecosystem services and socioeconomic activities are spatially or territorially specific. In this sense, different types of PES market have to adapt and coevolve with different ongoing development processes.

Food Consumption Patterns and Sustainable Natural Resources Management in the Mediterranean Region

Sustainability of food systems and diets is not simply related to health concerns as it also involves environmental impacts. In fact, diets are major players in biodiversity erosion, natural resources degradation, climate change, etc.. The paper aims at analysing the main environmental impacts of the Mediterranean food consumption patterns on land and water resources and biodiversity. It provides a review on water and land resources and biodiversity in the Mediterranean and an analysis of the livestock sector impacts on ecosystem services. The most recent FAO food consumption statistics and standard impact data from different sources （e.g., Water Footprint Network; Mekonnen ＆ Hoekstra, 2010; Ewing et al., 2010） were used to calculate and discuss environmental impacts, i.e., water, carbon and ecological footprints. Mediterranean diets promote biodiversity use, conservation and sustainable natural resources management. They are more respectful of ecosystems and have lower environmental impacts than Northern Europe and American diets.

Economic Valuation of Environmental Services： Increasing the Effectiveness of PES Schemes in Developing Countries？

Payments for ecosystem service （PES） schemes have spread all over developing countries in the last 20 years or so. PES schemes often have high opportunity costs in terms of foregone uses of goods and services offered by the environment. It is within this scope that economic evaluation of environmental goods and services plays a role. In this paper we surveyed articles and studies that report application of economic environmental valuation procedures in PES schemes. Special attention was paid to data collection and analysis, to theoretical robustness of its procedures and to the aggregation of estimated value. We also scrutinize how these estimates had been incorporated into PES schemes, in particularly in the assessment phase of these schemes. Empirical data from Brazil and other Latin American countries were used, particularly those in the Amazon Basis. Our results reveal a frequent overestimation of the values of ecosystem services calculated through the use of economic valuation methods. Values have been estimated by production function methods （opportunity cost, preventive expenditures, recovering cost or dose-response methods）. As a consequence, estimated values reflect much more willingness to accept compensation by supplier and rarely willingness to pay by consumer of these ecosystem services. Besides this distance between supply and demand, application of valuation methods did not account for problems such as uncertainty, risks, and lack of information. All these limitations have led to wrong decision-making.

Village Woods and Agricultural Biodiversity in South Korea

In South Korea vilage woods are composed of an isolated tree or a number of trees, located near rural vilages and which have an apparent fengshui shape. Vilage woods also function as wildlife habitat and promote agricultural biodiversity. Here vilage woods were classiifed in to four types （natural forest, semi-natural forest, half-natural forest and artiifcial forest） and 23 main tree species（dominant or sub-dominant species） identiifed.Pinus densilfora is dominant at 50 sites, and Zelkova serrata is dominant at 45 sites. Across village woods, emerged plants comprise 125 families, 519 genus and 1081 species. In spite of the extremely small area of village wood, 100 000 km2 or 0.00278% Korea’s territory, this ecosystem has an important biodiversity and habitat conservation function. Vilage woods are not only a base for conserving biodiversity, but also deliver ecosystem services in South Korea.

Human Response to Degradation of Ecosystems

Our ecosystem provides us with essential services, most of which come without a price tag and hence are assumed to be ＂free gifts of nature＂ available in plenty. Much of the neoclassical thought and analysis was based on this assumption until recently. The dynamic rise in population due to rapid industrialisation and urbanization has caused the realisation that ecosystem services are also limited. Environmental degradation is a common term used to describe the loss or impairment of ecosystem services. Migration is often a consequence of environ- mental degradation; when ecosystem services are impaired and survival comes at stake. But is the degradation of essential ecosystem services sufficient to motivate people to relocate？ Through a review of literature on migration and environmental degradation, this paper strives to answer the above question along with exploring ways how monitoring the deterioration of the environment on time can spare human inhabitants of any ecosystem the pains of migration in search of better means of survival and sustenance.