RS和GIS支持下的四川省生态环境状况评价

以四川省为例,利用RS和GIS技术及相关理论,建立区域生态环境综合评价指标体系与四川省生态环境本底数据库,采用国家环境监测总站2006年颁布的《生态环境状况评价技术规范》,建立生态环境质量评价模型,通过模型的空间叠加分析得到四川省生态环境状况综合评价结果,根据评价结果将四川生态环境分为5级,分级结果表明:四川省生态环境东部明显好于西部,盆地好于山区,三州地区生态环境压力大。这与四川各地的自然条件、气候条件、资源开发与利用等因素具有较好的相关性,也与实地考察和历史资料分析结果相吻合,表明评价模型是科学客观的。     

Effect of Urmia Lake's drying on groundwater corrosion and scaling potential in the northwest of Iran (Case study: Spring and summer, 2015)

The most common problems in water distribution systems are corrosion and scaling, which cause both economic and customer health problems. The aim of the present study is to report the relationship between Urmia Lake's drying and the corrosion and scaling potential of groundwater used as drinking water during the spring and summer of 2015. Groundwater samples were collected from all of the catchments of the Urmia Lake basin, and the characteristics of the water were used to determine the corrosive and scaling indices using the Langelier Saturation Index and the Ryznar Stability Index. The results showed that the total dissolved solids measurement of the samples collected from the islands of Urmia Lake was higher than the maximum value of the standard level. In addition, the hardness in 36% of the zones was higher than that of the maximum suggested level. The concentration of calcium was lower than that of the standard, but the rest of the parameters were in the standard level range. Also, the results showed that the water of the Urmia Lake basin tends to be very scaling and corrosive. In order to control the corrosion and scaling caused by groundwater drawn from the catchments around Urmia Lake, measures should be taken to prevent Urmia Lake's drying and to manage the groundwater around this area. It is also suggested that a laboratory study regarding the condition of the distribution system be carried out to adjust the effective parameters, such as the pH.     

Lake management under severe drought: Lake Mead,Nevada/Arizona

Drought can affect both the quantity and quality of water in lakes and reservoirs, yet larger, highly managed waterbodies, such as Lake Mead, may be somewhat buffered from drought effects. From 2000 to present, Lake Mead has experienced a 71% decline in volume; however, influent water quality has remained high and consistent outflow volumes through Hoover Dam have been maintained. Furthermore, management activities, such as increased removal of phosphorus by wastewater dischargers and legacy contamination cleanup efforts, have been initiated since the drought began. These efforts have led to small improvements in values of water quality parameters, such as phosphorus, nitrogen, and perchlorate, despite loss of volume for dilution of constituents, and consequently, decreased residence time. As the drought continues, Lake Mead is projected to continue declining in volume, inflows are projected to become warmer, and the population of Las Vegas is projected to grow, potentially adding additional stress to the hydrologic system. Maintenance of outflow may mitigate some potentially negative consequences, and understanding the drivers behind continued high water quality despite prolonged drought is important to continue to maintain the health and vitality of the entire Lower Colorado River Basin.     

垃圾渗滤液调节池工艺设计

分析了影响垃圾填埋场渗滤液产生量多少的因素,比较了渗滤液产量的计算方法,并通过工程实例计算了渗滤液产量及调节池容积,在调节池设计上采用了浮盖技术,以满足渗滤液预处理功能和控制蚊蝇滋生及臭气外逸,目的是便于有关人员在使用《生活垃圾卫生填埋技术规范》(CJJ17—2004)标准时能正确理解调节池设计规定。     

汉水流域水环境安全管理对策探讨

汉水是长江中游北岸跨省级行政区的一级支流。汉水流域上游的丹江口水库为规划中的南水北调中线工程水源地 ;流域中下游工农业生产发达 ,人口密集。因此 ,汉水流域水环境安全问题备受人们关注。初步研究了汉水流域水环境安全管理问题 ,首先探讨流域水环境质量的时空变化特征 ,然后就流域水环境安全的主要点源和非点源压力因素进行了识别。结果表明 :在时间上 ,汉水流域水质总体上有逐年恶化的趋势 ,枯水期存在点源污染问题 ,丰水期存在点源和非点源污染问题 ;在空间上 ,上游干流个别江段和整个流域多数支流水质污染严重 ,丹江口水库水质良好 ,中下游干流水质时有污染现象 ;河南 -湖北省界水体存在水质污染问题。最后 ,根据汉水流域水环境质量特征及存在的问题 ,从流域水资源保护体制、法制建设、管理的理论与方法、监测和评价的内容与方法、流域水环境规划与科研、流域生态建设、行政区之间利益分配、现代高新技术的应用等方面提出了国家层次和流域层次的水环境安全管理对策     

基于DPeRS模型的渭河典型断面汇水区面源污染评估及污染成因分析

近年来甘肃渭河桦林断面月度水质不稳定达标的问题引起了管理部门的广泛关注,掌握桦林断面汇水范围面源污染现状,对控制流域面源污染和促进水质稳定达标具有重要意义。采用遥感分布式污染估算（DPeRS）面源污染评估模型,对2018年黄河流域甘肃桦林断面汇水区面源污染空间分布特征进行分析,开展多类型污染量产排特征解析。结果表明：农业面源污染量方面,2018年甘肃桦林断面汇水区总氮（TN）、总磷（TP）、氨氮（NH⁺₄-N）、重铬酸盐指数（COD_Cr）面源污染排放量分别为11 591,2 697,7 141和1 458 t,入河量分别为2 184,512,1347,263 t;空间分布上,氮型（TN和NH⁺₄-N）排放负荷高值区主要分布在陇西县、武山县县段和岷县县段;武山县县段TP排放负荷较为突出;COD_Cr型面源污染高负荷区主要分布在陇西县、渭源县县段和武山县县段。农业面源污染物入河排放负荷空间分布差异明显,氮磷型（TN、NH⁺₄-N和TP）入河高负荷区主要分布在武山县县段、陇西县、临洮县县段;COD_Cr型面源污染入河高负荷区呈分散分布。漳县西部地区水土流失量较高,漳县西部、陇西县和渭源县县段北部局部地区泥沙负荷量较高。枯水期污染治理仍是保障水质稳定达标的关键期,农田径流是渭河桦林断面所在汇水区氮磷型面源污染的首要污染类型,畜禽养殖是COD_Cr型面源污染的首要污染类型。     

Evaluation of CFSR climate data for hydrologic prediction in data‐scarce watersheds: an application in the Blue Nile River Basin

Data scarcity has been a huge problem in modeling the water resources of the Upper Blue Nile basin, Ethiopia. Satellite data and different statistical methods have been used to improve the quality of conventional meteorological data. This study assesses the applicability of the National Centers for Environmental Prediction's Climate Forecast System Reanalysis (CFSR) climate data in modeling the hydrology of the region. The Soil and Water Assessment Tool was set up to compare the performance of CFSR weather with that of conventional weather in simulating observed streamflow at four river gauging stations in the Lake Tana basin — the upper part of the Upper Blue Nile basin. The conventional weather simulation performed satisfactorily (e.g., NSE ≥ 0.5) for three gauging stations, while the CFSR weather simulation performed satisfactorily for two. The simulations with CFSR and conventional weather yielded minor differences in the water balance components in all but one watershed, where the CFSR weather simulation gave much higher average annual rainfall, resulting in higher water balance components. Both weather simulations gave similar annual crop yields in the four administrative zones. Overall the simulation with the conventional weather performed better than the CFSR weather. However, in data‐scarce regions such as remote parts of the Upper Blue Nile basin, CFSR weather could be a valuable option for hydrological predictions where conventional gauges are not available.     

A Cooperative Approach to Reduce Water Pollution Abatement Cost in an Interjurisdictional Lake Basin

A cooperative approach via transfer fee was developed to improve the cost‐effectiveness of water pollution control in interjurisdictional lake basin management in China. Different from the existing literature that studies water quality trading and pollution reduction at micro levels (i.e., focusing on enterprises and firms), this article explores cooperative pollution reduction strategies from a macro level, targeting multiple jurisdictional regions. The merits of this new approach include: (1) improving the cost‐effectiveness of pollution reduction by making use of the cost differentiation in pollution reduction between industries and municipal sewage plants, and between different administrative areas; (2) managing payments for ecosystem services by horizontal transfer payment; and (3) incorporating the concepts of game, cooperation, coordination, and watershed‐based management in implementation. For empirical demonstration, a bilevel optimization model was built and calibrated using the 2005 data of the Lake Tai basin to work out the optimal solutions for cooperative chemical oxygen demand (COD) reduction. Results show that policies based on this new approach can significantly reduce the overall COD abatement costs for the basin as well as the individual jurisdictional regions compared to the current practice.     

Runoff variation affected by precipitation change and human activity in Hailiutu River basin,China

For recent years,runoff generation and hydrological processes in Hailiutu River basin have been greatly changed by climate change and human activity,especially water and soil conservation construction.In this study,the trends in precipitation,evapotranspiration(ET)and river runoff as well as the effects of precipitation change and human activity on runoff variation have been studied.The results showed that during 1960-2000,annual precipitation and river runoff,monthly precipitation and ET in September and October as well as monthly runoff in all months showed a significant decrease.In addition,peak flow and base flow had a large decrease.Under the joint influence of precipitation change and human activity,the mean annual runoff decreased by 35 million m3 from the baseline period(1960-1985)to the change period(1986-2000),which accounted for 60.9%and 39.1%of the total runoff decrease,respectively.Precipitation change played a primary role in the decrease of annual runoff whereas human activity,particularly water and soil conservation construction,also had remarkable impacts on runoff variation.     

南四湖流域水环境承载力评价指标体系构建

针对目前水环境承载力概念及评价指标体系研究中存在的问题,构建了流域水环境承载力概念模型,根据评价指标筛选原则,建立了南四湖流域水环境承载力评价指标体系,包括水环境承载能力、水环境压力、水环境承载状态和社会经济调控能力4部分,共有57个具体指标,从而为制定流域保护规划和管理政策提供技术支持,为寻求流域水环境承载力的提高途径和措施提供科学依据。