Using fuzzy set theory to address the uncertainty of susceptibility to drought

This paper presents the technical aspects of a new methodology for assessing the susceptibility of society to drought. The methodology consists of a combination of inference modelling and fuzzy logic applications. Four steps are followed: (1) model input variables are selected—these variables reflect the main factors influencing susceptibility in a social group, population or region, (2) fuzzification—the uncertainties of the input variables are made explicit by representing them as ‘fuzzy membership functions’, (3) inference modelling—the input variables are used to construct a model made up of linguistic rules, and (4) defuzzification—results from the model in linguistic form are translated into numerical form, also through the use of fuzzy membership functions. The disadvantages and advantages of this methodology became apparent when it was applied to the assessment of susceptibility from three disciplinary perspectives: Disadvantages include the difficulty in validating results and the subjectivity involved with specifying fuzzy membership functions and the rules of the inference model. Advantages of the methodology are its transparency, because all model assumptions have to be made explicit in the form of inference rules; its flexibility, in that informal and expert knowledge can be incorporated through ‘fuzzy membership functions’ and through the rules in the inference model; and its versatility, since numerical data can be converted to linguistic statements and vice versa through the procedures of ‘fuzzification’ and ‘defuzzification’.     

山东寿光沿海湿地生态系统健康诊断

以寿光沿海湿地为例，运用二级模糊综合评判模型对湿地生态系统的健康进行了综合评价。首先从湿地生态特征、整体功能特征及外部社会环境三方面选取23项评价指标，构建了寿光沿海湿地生态系统健康的综合评价体系，整个指标体系分为单项指标、亚类指标和综合指标三个层次：然后进一步把评价指标划分为很健康、健康、亚健康、疾病4个等级，运用定量、半定量与定性相结合、定性描述等多种手法界定了等级划分标准，确定了各指标的等级隶一度，构造了隶属评判矩阵；通过专家咨询法．确定了各指标的权重，构造了权重向量；最后，运用加权平均型二级模糊综合评判模型对寿光沿海湿地生态系统健康逐级进行评价。评价结果显示，该温地系统在最大隶属程度上处于亚健康状态。     

鄱阳湖典型湿地生态环境脆弱性评价及压力分析

采用理论研究与实地调查、定性和定量相结合的研究方法,建立了完整的鄱阳湖典型湿地生态环境脆弱性评价指标体系,并运用模糊数学的方法对鄱阳湖湿地生态环境脆弱性进行评价。结果表明,鄱阳湖典型湿地生态环境脆弱性为0768,属于轻度脆弱状态;在亚类指标中,生态特征脆弱状态为0732,处于轻度脆弱状态,整体功能脆弱状态为0868,处于微脆弱状态,社会环境脆弱状态为0668,处于轻度脆弱状态。通过压力分析,发现影响鄱阳湖典型湿地生态环境脆弱性的制约因素主要是外部社会环境因素,主要包括围垦、不当的消灭血吸虫病措施、经济贫困与落后的生产生活方式以及亟待加强的湿地管理体制。     

鄱阳湖湿地植物生态系统结构及湖水位对其影响研究

通过对鄱阳湖水文过程和湖盆地形特点的分析,利用3S技术对鄱阳湖湿地进行了分类,研究了各种类型湿地植物生态系统的生境、主要植物群落结构和分布规律。结果表明,鄱阳湖湿地植物生态系统结构复杂,生物多样性极其丰富。湿地植物是以根茎为主要繁殖器官的克隆繁殖植物,以集群分布为主要特点。在宏观尺度上受地形高程、湖水位和洲滩出露时间制约,不同植物群落沿水分梯度分布;在景观尺度上受到土壤含水量、地下水埋深和土壤结构影响,形成水平镶嵌结构;微观尺度上还与微地形和土壤养分密切相关,部分区域表现为复合体结构。湿地植被对水分梯度的敏感性,导致湿地植物生态系统的易变性和脆弱性。近年来,鄱阳湖水位过低且持续时间长,使生态系统遭受一定损害。     

基于云推理和模糊逻辑关系模型的干旱等级预测方法研究

针对月平均降水量时间序列存在模糊性和随机性的特点,给出一种结合云推理和模糊逻辑关系的干旱等级预测方法。采用徐州站1951~2014年逐月降水量数据,通过计算标准化降水指数(SPI),得到实测干旱等级序列,以1952~2013年SPI指数数据作为样本数据,并提取样本模糊时间序列的52条模糊逻辑推理规则,将某月份的SPI指数数据作为输入变量,利用云发生器进行云推理,得到未来相应月份的干旱等级预测结果。结果表明,研究方法对干旱发生具有一定预测能力,尤其是对无旱的预测比较准确,但是对于干旱状态突变的预测能力较弱,主要是由于发生严重旱灾的可能性较少,导致模糊推理规则较少。因此,对于江苏省以轻旱为主的苏北地区,可以作为早期干旱预警的参考。     

Estimation on wetland loss and its restoration potential in Modern Yellow River Delta,Shandong Province of China

Wetland is one of the most important ecosystems with varied functions and structures, and its loss has been a major issue. Wetland loss in Modern Yellow River Delta (MYRD) becomes a serious environmental problem, so its restoration attracts a great deal of attention from academia and governments. This article proposes a GIS-based multi-criteria comprehensive evaluation methodology for potential estimation of wetland restoration, using MYRD as an example. The model uses four kinds of data (hydrology, terrain, soil, and land use) and could be adapted by planners for use in identifying the suitability of locations as wetland mitigation sites at any site or region. In the application of the model in the MYRD, the research developed a lost wetland distributed map taking the better wetland situation of 1995 as the reference, and elevated the overall distribution trends of wetland restoration potential based on wetland polygon. The results indicated that the total area of wetland loss from 1995 to 2014 was 568.12 km², which includes 188.83 km² natural wetland and 21.80 km² artificial wetland, respectively. The areas of lost wetland with low, middle, and high resilience ability are 126.82 km², 259.92 km², and 119.59 km², occupying 25.05%, 51.33%, and 23.62%, respectively. The high-restoration-potential wetland included 98.47 km² of natural wetland and 21.12 km² of artificial wetland, which are mainly bush, reed, and ponds. The high-restoration-potential wetland is mainly distributed in the vicinity of Gudong oil field, the Yellow River Delta protected areas, and the eastern sides of Kenli county and Dongying city.     

长江中下游湿地保护与流域生态管理

湿地是地球上具有多功能的、独特的生态系统,是人类最重要的生存环境之一。长江中下游湿地保护必须从流域管理角度进行规划和保护,应由过去主要是单块湿地保护向按流域系统保护的转变。具体可采取以下措施：在流域内建立统一协调机制,对流域湿地进行保护与合理利用,合理布局,统一规划;按湖泊流域和物种分布整合现有保护区,建立新的湿地保护区,解决目前管理上的制约问题;大力开展湿地修复重建;推进退耕还林、长江防护林等工程建设,发挥森林治理水土流失、涵养水源的作用;在保护的前提下科学合理地利用长江中下游湿地资源,开拓新的生产力;同时加强湿地科学研究。     

湖北省涨渡湖流域湿地变化及其动因分析

基于1987年、1993年、2000年TM卫星遥感数据,在GIS技术支持下,建立了涨渡湖流域土地利用数据库,通过提取湿地信息,对该流域湿地资源动态变化进行了分析,并从人文因素方面阐述了湿地变化的原因。研究表明： ① 涨渡湖流域土地利用格局是以湿地为主,其他用地为辅的形式;②1987～2000年涨渡湖流域地区天然湿地和人工湿地均减少,其中水田减少面积最大; ③ 在1987～2000年14年期间,影响涨渡湖流域湿地结构变化的主要因素是产业结构调整、围湖（滩地、沼泽）造塘、城市化等。     

基于知识的洞庭湖湿地遥感分类方法

湿地遥感影像分类是遥感研究的一大难题。分析洞庭湖不同湿地类型在遥感影像上的光谱曲线规律,利用两个季节的洞庭湖ETM数据,并辅助以物候特征和地面GIS信息,通过遥感软件Erdas Image的专家分类知识库建立决策树分类方法,结合研究区的DEM进行洞庭湖湿地的影像分类,通过专家分类器分层次实现了包括水体、泥沙滩地、防护林滩地、湖草、芦苇滩地和苔草滩地以及其他水体7种湿地类型的分类。相比传统分类方法,专家分类过程以规则为基础,可以同时利用多个条件进行分类,减少了数据处理时间,同时还提高了分类精度,最终得到试验区较为可靠的遥感分类图像。     

Economic valuation of Shadegan International Wetland,Iran: notes for conservation

Wetlands are among the most productive ecosystems on the earth. They produce various market and non-market goods and services, which have a significant role in human welfare. Despite the great opportunities from sustainable development, wetlands all over the world are under serious threat from a diverse range of non-sustainable activities. One of the major reasons for excessive depletion and the conversion of wetland resources is due to underestimating the non-market values of wetlands during development decisions. Shadegan International Wetland (SIW) in southern Iran is one of these wetland areas that is threatened by undervaluation and overexploitation from commercial activities. This study utilizes the contingent valuation method to estimate the economic benefits of SIW from the view point of peoples’ willingness to pay (WTP). The logit model was defined based on dichotomous choice to measure individuals’ WTP. The estimated mean WTP was US$ 1.74 per household as a onetime donation. This study concludes that the benefits of SIW to society could encourage managers to set priorities to ensure that the health of the ecosystem, its integrity, and its uniqueness would be conserved in a proper manner.     

基于神经元网络模型的崇明东滩湿地生态系统健康评估

崇明东滩湿地位于崇明岛的东端,是全球重要的生态敏感区域,由于受到人类活动的干扰,生态系统健康遭受威胁,因此有必要对其健康进行定量的评价研究。以崇明东滩湿地为研究区域,以生态系统健康理论为基础,选取地形地貌、环境、生物、人类干扰等指标,并将研究区的健康分为五级,建立东滩湿地健康评价指标体系。结合GIS的技术,以网格为评价单元,并在神经元网络模型理论和技术的支持下,提出了一个分布式神经网络湿地生态系统健康评价模型,定量的分析崇明东滩湿地的健康状况,为湿地的合理利用与保护提供决策支持和科学依据。研究结果从空间上显示了崇明东滩湿地不同区域的健康状况,总体来说处于一个比较健康的状态,但健康状态较好的区域面积只占30％,相对一般区占70％,且生态系统健康将呈下降趋势。因此,需要对湿地加强管理,使湿地生态系统可持续发展。     

Wastewater management and the east-bound growth of the city of Kolkata: a compatibility analysis

Kolkata, home of 4.5 million people, is generating 1112 million liters of sewage per day and facing the challenge of managing this wastewater. The 125 km² wide wetland on the eastern fringe of the city, popularly known as the East Kolkata Wetlands is serving as a natural sewage treatment plant for more than a century where nearly 78 % of city sewage goes through an intricately designed canal network. This wetland is a designated RAMSAR site where the sewage treatment process is a rare example of an intertwined symbiotic relation between wastewater treatment and wetland aquaculture, where livelihood dependence of the local people on sewage-fed fisheries becomes of strategic importance in sustainable performance of the system. An aggressive urban expansion in the eastern fringe of the city is disturbing this age-old eco-balance by making this sewage water pisciculture less profitable. There is push factor due to reduced attraction of the wastewater fisheries and a pull factor due to emergence of alternative livelihood options through rapid urbanization. To protect wetland in its original form, the civil society and the administrative authorities are designing active interventions. However, these are not generating expected results as these instruments are targeting to mitigate the push factor only without paying much heed to the push–pull interactions.     

湿地生态系统服务功能评价模式的不足与改进

本文基于对湿地生态系统服务功能评价研究发展历程的回顾,结合湿地资源保护面临的严峻形势以及社会经济发展对评价研究的现实要求,重点剖析了湿地生态系统服务功能的现状评价模式在研究定位、评价内容、评价方式和评价体系建设几个方面存在的主要不足,在此基础上提出相应的改进思路和方案.认为评价模式的改进应当以维持湿地生态系统健康和支撑区域社会经济可持续发展为研究目标,面向湿地生态系统管理方向补充评价内容,完善评价体系,强调人为活动干扰对湿地生态系统服务的影响及反馈分析,重视人类社会对服务功能需求的评价,并详细阐述干扰评价、需求评价和服务功能供需平衡分析的主要内容、方法和难点,总结湿地管理的意识和手段在服务功能评价各环节的体现.     

Using a functional approach to wetland valuation: the case of Zazari–Cheimaditida

This study proposes the valuation of wetland functions as an alternative to the conventional approach to wetland valuation, in order to derive indicators for decision-making in wetland management. It is illustrated that these functions can be valuated in terms of the goods and services they provide to society. Using a functional approach, the functions are identified and the goods and services they provide are explicitly allocated among them; then, the latter are valuated with the Contingent Valuation method. Statistical analysis of the data provides welfare measures that reflect the value of these functions. It is argued that the values of separate functions are more useful in policy-making than their aggregated value.

基于BMPs的鄱阳湖区小流域农村面源污染控制

鄱阳湖小流域农村面源污染严重,环境问题不断加剧。通过背景值调查与污染源解析,显示农村生活和种植业是鄱阳湖小流域农村面源污染的主要来源。采取集成式BMPs模式,将源头控制与末端治理相结合,充分利用当地优势,合理搭配植物缓冲带、沟渠湿地、人工湿地,兼性塘等,实现氮、磷流失的有效拦截,达到有效控制示范区小流域农村面源污染目的,从而为鄱阳湖农村面源污染控制提供借鉴。结果表明： BMPs系统污染物去除能力高,运行成本低。系统单位面积削减总量分别为CODcr 71017 kg、SS 11491 kg、TP 408 kg、TN 3593 kg、NO-3 N 474 kg、NH+4 N 1918 kg,而运行成本不到01元/t。整个系统中尤以表面流人工湿地减污效果最好,耐负荷冲击能力最强。沟渠湿地整体去污能力不低,但耐冲击负荷能力弱,易受外界因素的影响。为加强减污效果,可通过完善生态系统尤其是挺水性植物加以改进     

基于CLUE-S模型的湿地公园情景规划——以南京长江新济洲国家湿地公园为例

基于计算机模型的湿地公园规划具有低成本、高效率、多情景等优点,可以为规划研究提供初步方案的评优和选择。将CLUE-S模型运用到湿地公园规划中,结合生态保护情景和旅游开发情景的设定,对新济洲湿地公园进行2020年景观格局模拟预测,最后从湿地鸟类穿越的最小累积阻力模型角度,对两种情景进行了比较分析,得出如下结论:(1)对CLUE-S模型在研究区的适用性进行验证,经过计算,模拟的精度检验指数Kappa值为0.763,表明CLUE-S模型用来做新济洲湿地公园景观格局变化的预测模型具有良好的可靠性;(2)土壤有机质含量是推动新济洲湿地公园景观变化的最重要驱动因子,其影响力度远远高于其他因子;(3)通过建立MCR模型可以发现,两种情景都具有各自的优缺点,对于生态保护情景需要注意的是拓宽湿地鸟类穿越廊道,减少最小累积阻力路线生态缓冲区内的人为干扰。而对于旅游开发情景来说,构建整体的生态串联性则显得尤为重要,需要在中部大阻力区域为湿地鸟类穿越开辟一条良好的保护通道。     

Regional challenges in tourist wetland systems: an integrated approach to the Ria Formosa in the Algarve, Portugal

Coastal change and coastal erosion have been a long-existing source of environmental changes. Traditionally, regional changes in wetland systems and their relations to agriculture, industry and urbanization are a major cause for concern. Nowadays, coastal distress has reached even global proportions: the problems of coastal change are strongly linked to the loss of fragile ecosystems, eutrophication and loss of biodiversity. Given that over 70 % of all human activity is in coastal areas, it is clear that many environmental and socio-economic changes occur at a local level and manifest themselves in a spatial context. The physical effect on the geographic morphology is evident in the related consequences for land use. A deep understanding of the changes in land use, and simultaneously in coastal erosion, calls for the integrated monitoring of the most relevant effects in fragile regions. The Ria Formosa wetland system is a unique and very special wetland system in the Algarve (Portugal) and has been integrated in the NATURA 2000 network. The strong symbiosis between nature, agriculture and fisheries, as well as tourism, in the Algarve has led to spatial-ecological synergy. By using coastal recession analysis techniques by means of remote-sensed imagery from 1987, 1989, 2000 and 2007 and by combining this information with available data sets on surface erodibility, a cost surface on multitemporal transitions of land-use classes from the CORINE Land Cover data allows us to assess and integrate a decision-making framework by means of GIS. The novelty of this combined approach to land-use management is the blend of spatial analysis and remote-sensing techniques that share important information on ecosystems at risk. Our findings suggest a growing concern to the area brought by anthropogenic activity. This is studied to a spatial accounting of the distribution of land changes and transitions, where (1) a significant loss of coastal area is witnessed along the Ria Formosa, leading in particular to loss of agricultural land. (2) This loss is underpinned by an increase in leisure facilities to respond to the tourism demand of the region of the Algarve, while landscape metrics suggest that these areas are more volatile for coastal erosion. (3) Simulation through Markov chains on the land use and effects of urban, agricultural, forest and wetland dynamics suggests that by 2026, it is expected to continue to have an increase in urban land, leading to an augmented vulnerability of coastal erosion processes brought by the loss of forest areas which protect from erosion given the root system that directly protects from the existing wave energy and helps sedimentation processes. The above methodology and the availability of data that are freely available render such a combined approach interesting for many other regions of the world, where tourism, coastal change and regional balance are of the utmost importance for sustainable development. The advanced research tools presented here are of critical importance for coastal zone degradation management.     

三峡库区湿地生态建设与保护利用

三峡工程的兴建给库周地区带来了前所未有的发展机遇,但同时也给库区的生态环境建设带来了新的问题。水库蓄水将导致库区的人地矛盾更加突出,环 境容量不足等等。三峡水库周边的水位变动区域的干、湿交替区——湿地系统,具有独特的结构、功能和环境景观特点,新建大型水库周边湿地开发利用对库区移民安置及经济发展意义重大,应对其进行有效、合理、安全的综合开发利用。三峡库区湿地的水位具有年内周期性涨落变化特点,以库区水位变动带来划分不同的区域,并结合库区涨落带的坡度、土壤和水文等条件,探索与不同湿地区域段相适宜的保护和开发利用方式。这种因地制宜的湿地生境开发利用途径对缓解库区人地矛盾,改善库区生态环境和景观将发挥积极作用。     

制度分析与发展框架下流域生态补偿的应用规则:基于新安江的实践

探索流域生态补偿是推进生态文明建设、依靠制度保护环境的重要举措。当前,流域生态补偿制度正在广泛地改变流域生态环境和流域水资源利用的使用方式。不过,该制度受到复杂规则体系的约束,这些规则以及规则采取的形式,可能会对该制度的最终结果产生关键影响。本文从制度分析与发展(IAD)框架出发,讨论流域生态补偿的应用规则体系,剖析我国首个跨区域上下游横向生态补偿机制的试点项目——新安江生态补偿,分析有可能实现持续利用流域生态系统服务的应用规则,及其在流域生态补偿中的逻辑关系和具体表现,并从效率、公平、问责、适应性四个方面对规则进行评估。研究表明,流域生态补偿规则体系为规定补偿主体、增加生态系统服务额外性、界定生态补偿的条件性、调节利益分配以及与其他社会目标相适应等行为提供了普遍遵循的规则,为解决流域生态补偿中存在的一般性问题提供解决方向。新安江实践表明,位置规则明晰补偿主体和责任、边界规则选择参与者标准、选择规则规定允许的行动集合、偿付规则创新补偿渠道和分级制裁,是跨区域流域生态补偿机制建立的基石;信息规则确定可用完整的信息、聚合规则适当放权于当地居民、范围规则建立与流域匹配的管理机构,是促进流域生态补偿持续性的重要因素。通过创造责任共担的多元职位规则,改进市场化的边界规则和偿付规则,建设多元化、市场化的流域生态补偿制度,形成有效的补偿规则体系,将有利于流域生态补偿制度在更大范围、更广领域实现成功应用。