A Method for Improving the Management of Controversial Wetland

Valley bottom wetlands in agricultural landscapes often are neglected in national and regional wetland inventories. Although these areas are small, located in the bottomlands of the headwater catchments, and scattered in the rural landscape, they strongly influence hydrology, water quality, and biodiversity over the whole catchment area. Valley bottom wetlands often are considered as controversial wetlands. Awareness of the functional role of wetlands is increasing, in parallel with their progressive disappearance in intensive farming landscapes. The need to improve tools for controlling wetland management is a primary consideration for decision makers and land users. This article proposes a method for the inventory of valley bottom wetlands. The method is based on the functional analysis of potential, existing, and efficient valley bottom wetlands (the PEEW approach). Several indicators are proposed for checking the validity of such an approach. Potential wetlands are delineated by means of a topographic index using topographic and pedoclimatic criteria computed from a Digital Elevation Model and easily accessible databases. Existing wetlands are identified from observed surface moisture, the presence of specific wetland vegetation, or soil feature criteria. Efficient wetlands are defined through a given function, such as flow or pollutant regulation or biodiversity control. An analysis of areas at the limits between potential, existing, and efficient wetlands highlights land cultivated or drained in the past, which currently represents negotiating areas in which rehabilitation and other intended management actions can be implemented.     

淮河流域污染治理的思考

淮河流域工业污染源达标排放工作已取得成功。这将为其他流域污染治理提供经验。分析淮河流域污染治理工作中遇到的困难，总结成功经验，并对使淮河水体变清的方法与途径进行了研究和分析。     

长江中下游、浙西地区的上石炭统

本文系统阐述了区内上石炭统地层的分布范围、岩性特征、厚度变化及所含生物群面貌。     

东川小江流域生态环境与可持续发展

小江流域生态环境恶劣、泥石流灾害严重。为此，必须全面规划、控制人口，建设生态保障体系，控制水土流失和砂石化发展，加快综合治理步伐，改善生态环境，走可持续发展的道路。     

澜沧江流域云南段道路网络对生态承载力的影响研究

澜沧江流域道路工程的建设影响着区域土地利用格局和生态系统的空间分布,并进一步影响着区域的生态承载力,辨析道路对生态承载力的影响对区域生态管理具有重要意义.以谰沧江流域各县(市)为研究对象,利用生态足迹法研究了澜沧江流域生态承载力的时空及动态变化;以县域、市域为尺度.提取流域道路网络的结构特点,并进一步利用回归分析研究了道路的网络结构与生态承载力的关系.结果表明,谰沧江流域生态承载力存在着空间分布的不均衡,并呈现逐年降低的趋势;流域道路阿络中不同等级道路的组合结构变化明显,道路密度空间差异显著;县域尺度的回归分析表明,生态承载力与不同等级道路长度符合Gaussian模型、Reciprocal模型.与道路密度均能用ExponentiM Fit模型表示,生态承载力随道路密度的增加而减小;市域尺度上,生态承载力与道路密度的关系与县域尺度相一致.     

Official and folk flood warning systems: An assessment

Recent floods in West Bengal, India, focused public attention on the inadequacies of the flood warning system. This study examines some socioeconomic constraints on the communication of flood warning messages. It then looks at perceptions of, and responses by, villagers in a flood-prone region of West Bengal to official and folk flood warnings.The National Center for Atmospheric Research is sponsored by the National Science Foundation.     

金沙江河谷大气二氧化碳浓度变化特征及影响因子

大气CO₂是重要的温室气体,其浓度变化与气候变化、植物生长、人类活动等密切相关.为了解高原地区近自然状态下大气CO₂浓度变化及其影响因子,选取气象要素变化较明显、人为干扰较少的金沙江河谷为研究对象,在谷底江岸边的稀树草坪上设置观测点,对大气CO₂浓度和主要气象要素进行连续对照观测,经数据计算并采用Pearson相关系数对其相关性进行分析.结果表明:①研究区大气c（CO₂）日变化和年变化均具有波动性,日最高值（316.2 μmol/L）和最低值（291.0 μmol/L）分别出现在09:00和13:00左右,年最高值（338.9 μmol/L）和最低值（228.5 μmol/L）分别出现在10月和7月;季节性变化呈春、夏两季低于秋、冬两季的特征.②研究区大气c（CO₂）与温度呈显著负相关（r=-0.97,P < 0.01）,即白天温度高而大气c（CO₂）低,夜间温度低而大气c（CO₂）高.研究区大气c（CO₂）与相对湿度呈显著正相关（r=0.97,P < 0.01）,00:00-07:00大气c（CO₂）和相对湿度均缓慢上升,09:00-12:00大气c（CO₂）和相对湿度均快速下降.研究区大气c（CO₂）与风速呈显著负相关（r=-0.93,P < 0.01）,其与风对大气c（CO₂）有扩散作用相关;不同季节大气c（CO₂）最高值或最低值所对应的风向有所不同.研究显示,金沙江河谷大气c（CO₂）的时间变化特征明显,其与温度、相对湿度、风速、风向等气象要素的变化密切相关.      

云南怒江流域可持续发展对策研究

论述了云南怒江流域可持续发展的战略意义 ,分析了该区域生态经济格局与资源环境特征 ,并提出了怒江流域可持续发展的对策建议。     

Environmental Contaminants in Blood, Hair, and Tissues of Ocelots from the Lower Rio Grande Valley, Texas, 1986–1997

The ocelot (Felis pardalis) isan endangered neotropical cat distributed within asmall range in the Lower Rio Grande Valley (LRGV), inTexas, U.S.A. Studies of the impacts of environmentalcontaminants in wild cats are few. Approximately onefourth of the estimated population (about 100) ofocelots in the LRGV was sampled to evaluate theimpacts of chlorinated pesticides, polychlorinatedbiphenyls, and trace elements on the population. Hairwas collected from 32 ocelots trapped between 1986–1992,and blood was collected from 20 ocelots trappedbetween 1993–1997. A few blood samples were obtainedfrom individuals recaptured two or three times. Tissue samples from 4 road-killed ocelots were alsoanalyzed. DDE, PCBs, and Hg were some of the mostcommon contaminants detected in hair and blood. MeanHg levels in hair ranged from 0.5 to 1.25 g g^-1 dw,Se from 1.5 to 3.48 g g^-1 dw, and Pb from 0.56 to26.8 g g^-1 dw. Mean DDE concentrations in plasma ranged from 0.005 g g^-1 ww to 0.153 g g^-1 ww, and PCBs ranged from 0.006 g g^-1 ww to 0.092 g g^-1 ww. Mean Hg levels in red blood cells rangedfrom 0.056 g g^-1 dw to 0.25 g g^-1 dw. Concentrations of DDE, PCBs, or Hg, did not increasesignificantly with age, although the highestconcentrations of DDE and Hg were found in olderanimals. Overall, concentrations of DDE, PCBs, and Hgwere low and at levels that currently do not pose anythreat to health or survival of the ocelot. This isfurther supported by good reproduction of the ocelotin the LRGV, where adult females averaged about 1.5kittens/litter. Thus, it seems that the current majorthreat to recovery of the ocelot in the LRGV may behabitat loss, although potential impacts of newgeneration pesticides, such as organophosphorus andcarbamate insecticides need further study.     

水中亚硝酸根的现场测定及在地下水污染调查中的应用

以对氨基苯磺酸为重氮组分,α-萘胺为显色剂,采用便携式分光光度计,建立了环境水体中亚硝酸盐氮的现场快速测定方法,并将其用于玛纳斯河流域地下水污染调查评价。结果表明:亚硝酸盐氮在0.010~0.200 mg/L时有良好的线性关系,方法检出限为0.003 mg/L,加标回收率(n=5)为90.0%~104.0%,相对标准偏差为0.54%~1.27%,测定结果能够准确反映不同位置环境水体中亚硝酸盐的污染程度。该方法测试成本低,操作简便、快捷,尤其适用于地表水及地下水水质污染调查评价及污染事故的应急监测分析等领域。