Fish Assemblage Responses to Water Withdrawals and Water Supply Reservoirs in Piedmont Streams

Understanding effects of flow alteration on stream biota is essential to developing ecologically sustainable water supply strategies. We evaluated effects of altering flows via surface water withdrawals and instream reservoirs on stream fish assemblages, and compared effects with other hypothesized drivers of species richness and assemblage composition. We sampled fishes during three years in 28 streams used for municipal water supply in the Piedmont region of Georgia, U.S.A. Study sites had permitted average withdrawal rates that ranged from < 0.05 to > 13 times the stream’s seven-day, ten-year recurrence low flow (7Q10), and were located directly downstream either from a water supply reservoir or from a withdrawal taken from an unimpounded stream. Ordination analysis of catch data showed a shift in assemblage composition at reservoir sites corresponding to dominance by habitat generalist species. Richness of fluvial specialists averaged about 3 fewer species downstream from reservoirs, and also declined as permitted withdrawal rate increased above about 0.5 to one 7Q10-equivalent of water. Reservoir presence and withdrawal rate, along with drainage area, accounted for 70% of the among-site variance in fluvial specialist richness and were better predictor variables than percent of the catchment in urban land use or average streambed sediment size. Increasing withdrawal rate also increased the odds that a site’s Index of Biotic Integrity score fell below a regulatory threshold indicating biological impairment. Estimates of reservoir and withdrawal effects on stream biota could be used in predictive landscape models to support adaptive water supply planning intended to meet societal needs while conserving biological resources.     

秦岭生态补偿理论研究与实践进展

生态补偿是通过经济手段促进生态保护与受益地区利益共享的制度设计,是促进我国生态文明建设的重要举措。秦岭是我国重点生态功能区,国家重要的生态安全屏障。生态补偿作为协调秦岭地区生态环境保护和社会经济发展的制度安排,有助于推动该区生态环境的保护与可持续利用,对实现秦岭地区社会经济可持续发展、促进人与自然和谐共生具有重要意义。本文系统梳理了秦岭生态补偿相关理论研究与实践,主要包括秦岭在区域调水、森林生态效益、生物多样性保护、矿产资源开发等方面的生态补偿研究,以及秦岭生态补偿相关政策法规制定、南水北调、退耕还林（草）以及生态移民搬迁等具体生态保护工程补偿实践,并从补偿对象、补偿标准、公众参与、补偿方式几个角度探讨了秦岭生态补偿存在的问题,提出了秦岭生态补偿研究的建议与对策。     

A Fuzzy Logic Approach to Assess Groundwater Pollution Levels Below Agricultural Fields

A fuzzy logic approach has been developed to assess the groundwater pollution levels below agricultural fields. The data collected for Kumluca Plain of Turkey have been utilized to develop the approach. The plain is known with its intensive agricultural activities, which imply excessive application of fertilizers. The characteristics of the soils and underlying groundwater for this plain were monitored during the years 1999 and 2000. Additionally, an extensive field survey related to the types and yields of crops, fertilizer application and irrigation water was carried out. Both the soil and groundwater have exhibited high levels of nitrogen, phosphorus and salinity with considerable spatial and temporal variations. The pollution level of groundwater at several established stations within the plain were assessed using Fuzzy Logic. Water Pollution Index (WPI) values are calculated by Fuzzy Logic utilizing the most significant groundwater pollutants in the area namely nitrite, nitrate and orthophosphate together with the groundwater vulnerability to pollution. The results of the calculated WPI and the monitoring study have yielded good agreement. WPI indicated high to moderate water pollution levels at Kumluca plain depending on factors such as agricultural age, depth to groundwater, soil characteristics and vulnerability of groundwater to pollution. Fuzzy Logic approach has shown to be a practical, simple and useful tool to assess groundwater pollution levels.     

Use of Maryland Biological Stream Survey Data to Determine Effects of Agricultural Riparian Buffers on Measures of Biological Stream Health

This study was undertaken to determine the importance of riparian buffers to stream ecology in agricultural areas. The original Maryland Biological Stream Survey (MBSS) data set was partitioned to represent agricultural sites in Maryland's Coastal Plain and Piedmont regions. ANOVA, multiple linear regression (MLR), and CART regression tree models were developed using riparian and site catchment landscape characteristics. MBSS data were both stratified by physiographic region and analyzed as a combined data set. All models indicated that land management at the site was not the controlling factor for fish IBIs (FIBI) at that site and, hence, using FIBI to evaluate site-scale factors would not be a prudent procedure. Measures of instream habitat and location in the stream network were the dominant explanatory factors for FIBI models. Both CART and MLR models indicated that forest buffers were influential on benthic IBIs (BIBI). Explanatory variables reflected instream conditions, adjacent landscape influence, and chemistry in the Coastal Plains sites, all of which are relatively site specific. However, for Piedmont sites, hydrologic factors were important, in addition to adjacent landscape influence, and chemistry. Both Coastal Plain and Piedmont CART models identified several hydrologic factors, emphasizing the dominant control of hydrology on the physical habitat index (PHI). Riparian buffers were a secondary influence on PHI in the Coastal Plain, but not in the Piedmont. Between 40% and 70% of the variation in FIBI, BIBI, and PHI was explained by the “easily obtainable” variables available from the MBSS data set. While these are empirical results specific to Maryland, the general findings are of use to other locations where the establishment of forest buffers is considered as an aquatic ecosystem restoration measure.     

东莞运河水环境容量优化研究

本文根据东莞运河的特点,建立了适用运河特点的水环境容量优化模型,求解运河在不同的运行规律下最大的水环境容量值。建立的模型简单,易于求解,求解方程可以直接引用线性规划软件,计算得到的结果正确。      

用原生动物评价黄河兰州段的水质

报导了黄河兰州段的原生动物157种。根据原生动物群落构成特点;优势种群;污生指数和功能类群等指标对水质污染程度进行了评价,其各样点污染顺序是：库心（β_m）＜小川（β_m－α_m）＜新城桥（α_m）＜湟水桥(α_m）＜中山桥、包兰桥（α_m－ｐ_s）。这一评价结果与理化分析、底栖无脊椎动物和大肠杆菌的评价结果基本一致,表明原生动物可以作为宏观评价黄河水体污染程度的指示生物。     

河流水质系统的灰色规划方法和应用

借助于河流水质灰色模型,可以对河流水质系统进行灰色规划。灰色规划考虑了实际河流水质系统中客观存在的不确知因素和偶然因素影响,概述了河流水质系统的灰色规划模型的构造、河流水质系统灰色规划模型的求解及其在四川沱江水质系统规划中的应用。     

珠江三角洲城市供水与水污染整治战略研究

本文在系统分析珠江三角洲水环境水资源特点与经济发展需求的基础上,按照确保水源与合理利用水环境容量并重的原则,提出了三角洲各城市的供水与污水控制的总体布局。这种按水系的整体性确定区域各城市水污染整治战略的方法,对经济开发强度大的地区是普遍适用的,可以收到事半功倍的效果。      

滇池水污染控制系统规划

提出了滇池水污染控制系统规划模型,对污水集中治理措施,厂内治理措施与面源治理措施同时进行了优化,得出了滇池流域综合治理的优化方案,为滇池水污染控制提供了科学依据。      

灰色系统理论在湖泊水质预测建模中的应用

本文将灰色系统理论应用于湖泊水质预测建模研究,提出了湖泊水质预测的建模方法,并建立了某湖化学需氧量(COD)的GM(1,1)预测模型。