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’.     

Effects of Desertification Caused by Lithophaga lithophaga (Mollusca) Fishery on Littoral Fish Assemblages along Rocky Coasts of Southeastern Italy

Abstract:  We surveyed shallow, rocky reefs in southwestern Apulia (Mediterranean Sea) to assess the effects on coastal fish assemblages of the date mussel (  Lithophaga lithophaga ) fishery, an illegal practice that strips the rocky reef bare. We visually sampled fish four times over 15 months at three locations, one affected by date-mussel fishery and two controls. The fish assemblage at the affected location differed significantly from those at the control locations over all sampling times. Herbivorous fishes, sparids, and labrids (genus Symphodus ) contributed most to the differences between the affected location and controls. Lower densities of Symphodus spp. were observed at the affected location, whereas detritivorous fishes were recorded exclusively at control sites. Small serranids and sparids showed temporal trends that differed between the affected location and the control locations. Our results suggest that the date-mussel fishery affects fish assemblages chiefly through reduction of arborescent macroalgae (contributing to habitat complexity and primary production) and emphasize the need for more effective policing against this destructive practice.     

南水北调的资源、环境和社会效应

建设南水北调工程，对中国的水资源在地区间进行合理调配，将带动其他资源的合理配置与利用，还可改善环境，是社会发展的需要，又受社会条件制约，一旦突破建成，将促使社会生产力发生新的飞跃并持续发展。     

项目决策阶段清洁生产分析方法的研究

企业在建设项目决策时就应该按照清洁生产的原则，从源头控制污染。提出了在项目决策中，应从产品选择、工艺路线选择、主要设备选型和节能降耗4个方面进行清洁生产的分析方法，通过此分析方法的应用，可以避免项目决策中的环境失误和降低企业的环境风险。     

大型水利水电工程实施占用耕地补偿制度的思考

本文在分析长江三峡工程用地特点的基础上。对大型水利水电工程实施耕地补偿制度中的问题和困难进行调查研究，认为应从新的视角来认识大型水利水电工程的耕地占补平衡问题。进而探索耕地补偿制度实施的新途径和新方式。应在耕地总量动态平衡政策适当调整的基础上．将“以地补地”和“缴费补地”的方式相结合。既通过土地整理．在提商土地质量的前提下增加耕地的有效面积：又要落实耕地开垦费．扶持库区的土地整理。从而使库区的耕地占补制度顺利实施。     

DDT in fish from the Bulgarian region of the Black Sea

In spite of a worldwide reduction in the utilization of organochlorine pesticides (OCPs), they are still a problem for the aquatic environment and human health. The Black Sea is still being polluted with persistent chemicals, including OCPs. Aquatic organisms (sprat, scad, bluefish, shad, belted bonito, goby, and black mussel) with different feeding behaviours were sampled on a seasonal basis from the Bulgarian region of the Black Sea, and the concentrations of 13 OCP residues were determined. Although many of the OCPs were not detected in the samples, in all samples 1,1,1-trichloro-2,2-bis(4-chlorophenyl) ethane (DDT) was present mainly in the form of its metabolites 1,1-dichloro-2,2-bis(4-chlorophenyl) ethane (DDD) and 1,1-dichloro-2,2-bis(4-chlorophenyl) ethylene (DDE). Only about 12% of the total DDT was present as the parent compound pp-DDT, which suggests that it was not being used recently in the region. The total DDT concentrations were generally below 150 μg kg^-1 fresh weight, but higher levels—up to 354 μg kg^-1 fresh weight—were also measured for fish species with a high fat content. Between-species differences were observed, even when the concentrations were presented on a fat-level basis. DDT concentrations did not show any significant changes over the 2-yr sampling period. Fish sampled in the northern areas of the Bulgarian Black Sea coast seemed to contain higher DDT levels than those from the southern areas, suggesting a major (historical) influence of the Danube River. For permanent monitoring purposes, the utility of Black Sea gobies and scad should be considered.     

不同低碳氮比废水中好氧颗粒污泥的长期运行稳定性

为了研究好氧颗粒污泥系统处理低碳氮比废水的长期运行稳定性,采用低碳氮比（C/N）条件下逐步增加碳氮负荷的进水方法,分别在反应器A和B中接种好氧颗粒污泥,考察其长期运行过程中的理化性质、处理性能及应对冲击负荷的稳定性.其中A反应器的碳氮比一直维持在2,而B则由4逐步降至2.结果表明,在4℃存储30d的好氧颗粒污泥,经过25d的培养,其活性基本恢复,A、B反应器化学需氧量（COD）和氨氮（NH₄⁺-N）的去除效率均达到90%以上.在其后的稳定阶段,B反应器COD和NH₄⁺-N去除率达到90%以上,实现了完全硝化;而A反应器COD去除率仅80%左右,虽然NH₄⁺-N去除率最终也达到90%以上,但仅实现短程硝化.在冲击负荷阶段,A和B反应器COD去除率仍维持在80%以上,但是NH₄⁺-N去除受到很大冲击.A反应器NH₄⁺-N去除效率恶化,B反应器仅实现了部分硝化.整个运行过程,好氧颗粒污泥的物理性质受到的影响不大,A和B反应器的污泥容积指数（SVI₃₀）分别维持在60 mL ·g^-1和75 mL ·g^-1左右,混合液悬浮固体（MLSS）在5g ·L^-1和3.7g ·L^-1左右.颗粒污泥微生物群落分析表明,B反应器相对于A反应器丰富度和多样性更高.同时B反应器具有更高丰度的Zoogloea属,在颗粒中能产生更多的胞外蛋白促使颗粒结构更稳定,保证系统的长期稳定运行.以上结果表明,与C/N为2的好氧颗粒污泥系统相比,C/N为4的系统脱碳硝化效果好,抗冲击负荷能力强,更有利于颗粒污泥的长期稳定运行.     

黄海麻坑群沉积物磷的保存与转化及环境效应

基于对北黄海典型麻坑群海域某单位麻坑内部和外缘沉积物中不同赋存形态的磷、甲烷（CH₄）和硫化物等参数的分析,探讨了麻坑独特的环境中磷的转化与埋藏机制、沉积物-水体系磷的释放及对区域磷循环的影响.研究表明,沉积物中碎屑态磷（Det-P）是磷主要的赋存形态（>50%）,其次是有机磷（Org-P）、铁结合态磷（Fe-P）和自生态磷（Auth-P）,交换态磷（Exch-P）对总磷的贡献较小;麻坑内部与麻坑外缘处沉积物中溶解态活性磷（DRP）向水体的释放通量分别为2.84μmol/（cm²·a）和1.03μmol/（cm²·a）,对上层水体的贡献依次为19.6%和3.03%,是上层水体磷的重要来源.麻坑内外磷的埋藏速率与转化过程存在不同;研究区地下水的渗漏是磷的沉积速率和释放通量都普遍高的原因.北黄海麻坑区沉积物中磷的保存与转化还与浅层CH₄的逸出相关,潜在提高黄铁矿的生成速率.较高的沉积物-水界面磷通量必然对区域富营养化等生态环境问题产生深远影响,值得关注.     

平原农区村民居住空间特征与迁居意愿——以江苏省淮安市为例

选择地处苏北平原农区的淮安市所有15510个自然村和872414户农户全样本入户调查数据为分析对象,采用占比统计法和GIS空间分析,对村民居住空间特征与迁居意愿进行研究。主要结论如下：（1）在村落层面,平均规模小,单村独户多且村落分散,多数自然村远离镇区,近一半自然村位居“九靠近一滞洪”区域内。该格局是自然地理条件和人文因素综合影响形成的。（2）在住房层面,农村老旧住房比例高,全市40%农户在城乡同时拥有住房,但在城镇拥有住房率与到城区距离呈负相关,而农村住房空关率则呈现相反的空间格局。（3）在迁居意愿方面,54.1%的农户愿意集中居住且多意向实物安置,较低补偿标准和不便务农是不愿迁居的主要原因;移居城镇是货币安置农户的主要去向,留村和入镇集中居住是实物安置农户的主要去向。在迁居意向农户中,近90%选择政府统建方式,近80%愿意有偿退出宅基地和流转承包地。（4）村民居住空间特征和迁居意愿都存在明显的空间差异,两者之间存有内在联系且均受多种因素影响。     

南海浮游植物对沙尘和灰霾添加的响应

通过2016年5月~6月在南海3个站位开展的船基围隔培养实验,研究了沙尘和灰霾添加对南海浮游植物生长和群落结构变化的影响.结果发现,沙尘和灰霾添加由于提供了N、P等营养盐,整体上促进了浮游植物的生长,且促进程度与添加量密切相关.通过定量计算营养盐指数和叶绿素a累积浓度,发现培养期间叶绿素a累积浓度与沙尘添加浓度呈显著正相关关系（R²=0.87,P<0.01）;低浓度灰霾添加的作用与沙尘添加类似（R²=0.91,P<0.01）,但当灰霾浓度增大时,叶绿素a累积浓度的增加受到一定程度的抑制,这可能与灰霾中含有较高含量的毒性物质有关.各粒级浮游植物叶绿素a浓度的变化表明,沙尘和低浓度灰霾添加使浮游植物优势种群由超微型向小型和微型转变;在高浓度灰霾添加组,由于营养盐与毒性物质的综合作用,浮游植物粒级结构变化不明显.超微型浮游植物细胞丰度测定结果表明,沙尘对聚球藻、原绿球藻和超微型真核浮游植物均表现出促进作用,高浓度灰霾添加能够抑制聚球藻和超微型真核浮游植物的生长.