共查询到20条相似文献,搜索用时 15 毫秒
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Effect of irrigation water quality on organic matter, Cd and Cu mobility in soils of Central Mexico. 总被引:1,自引:0,他引:1
Untreated wastewater has been used for irrigation since 1912 at the Irrigation District 03, Central Mexico. Accumulated heavy metals are dominantly bound to the organic soil fraction. In a field study we evaluated the effect of wastewater irrigation on the quality of soil organic matter and the amount of water extractable Cu and Cd. In a column experiment we tested if water treatment affects the leaching of both metals and dissolved organic carbon (DOC) out of soils that have been irrigated for more than 90 years with untreated wastewater. The field study shows that long term irrigation increases the mineralizable carbon fraction and the DOC concentrations. The water extractable Cu and Cd concentrations also increase and correlate with DOC. In the column leachates the Cu concentrations also correlate with DOC, the Cd concentrations correlate with the sum of cations, chloride and DOC concentrations. Water treatment reduced Cd leaching, but it did have no substantial effect on Cu leaching. 相似文献
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Differentiation of wastewater effluent organic matter (EfOM) from natural organic matter (NOM) using multiple analytical techniques. 总被引:4,自引:0,他引:4
Using three analytical techniques of size exclusion chromatography (SEC), fluorescence excitation-emission matrix (EEM), and dissolved organic nitrogen (DON) measurement, differentiating characteristics of effluent organic matter (EfOM) from natural organic matter (NOM) have been investigated. SEC reveals a wide range of molecular weight (MW) for EfOM and high amount of high MW polysaccharides, and low MW organic acids compared to NOM. Clear protein-like peaks using fluorescence EEM were a major feature of EfOM distinguishing it from NOM. Fluorescence index (FI), an indicator to distinguish autochthonous origin from allochthonous origin, differentiated EfOM from NOM by exhibiting higher values, indicating a microbial origin. In EfOM samples, DON present in higher amounts than NOM. 相似文献
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以安徽省合肥市长丰县杜集水库灌区管理体制为例,并结合该灌区内典型用水农户,从效益与风险、现有灌溉制度效率、水资源配置的制度创新等方面进行了分析。 相似文献
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灌区农业水价成本补偿机制探究 总被引:1,自引:0,他引:1
针对宝鸡峡灌区农业供水价格政策性亏损问题,以近10年来供水成本与农产品价格指数上涨、政府水价调整比例、农业供水的特性、地位和作用、价格承受力等因素为基础,结合当前水管单位体制改革情况进行了综合分析,提出了建立灌区农业供水成本补偿机制的建议,供农业供水价格决策部门参考。 相似文献
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根据杭州市节水型农业的发展现状,结合该市的实际情况,提出几种推广节水型灌溉技术以及促进节水灌溉可持续发展的对策。 相似文献
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本文概括地阐述了洮北区的自然地理特点及其发展农业灌溉的必要性,从几方面揭示了当前灌溉存在的主要问题,并且有针对性地提出了对策及建议。 相似文献
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Understanding the fate of effluent organic matter (EfOM) and natural organic matter (NOM) through riverbank filtration is essential to assess the impact of wastewater effluent on the post treatment requirements of riverbank filtrates. Furthermore, their fate during drinking water treatment can significantly determine the process design. The objective of this study was to characterise bulk organic matter which consists of EfOM and NOM during riverbank filtration using a suite of innovative analytical tools. Wastewater effluent-derived surface water and surface water were used as source waters in experiments with soil columns. Results showed the preferential removal of non-humic substances (i.e. biopolymers) from wastewater effluent-derived surface water. The bulk organic matter characteristics of wastewater effluent-derived surface water and surface water were similar after 5 m soil passage in laboratory column experiment. Humic-like organic matter in surface water and wastewater effluent-derived surface water persisted through the soil passage. More than 50% of total dissolved organic carbon (DOC) removal with significant reduction of dissolved oxygen (DO) was observed in the top 50 cm of the soil columns for both surface water and wastewater effluent-derived surface water. This was due to biodegradation by soil biomass which was determined by adenosine triphosphate (ATP) concentrations and heterotrophic plate counts. High concentrations of ATP in the first few centimeters of infiltration surface reflect the highest microbial activity which correlates with the extent of DOC reduction. Good correlation of DOC removal with DO and biomass development was observed in the soil columns. 相似文献
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通过分析平谷区农业节水灌溉的现状,找出平谷区在节水灌溉方面存在的水量计量、重建轻管等八方面的问题,并提出了相应的解决方案,为平谷区农业节水灌溉事业发展、农民增收与构建和谐社会探索出了一条切实可行之路。 相似文献
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针对广西横县农村水利灌溉现状及存在问题,指出横县必须调整农业产业结构,发展节水农业;在搞好水利工程维护,提高水的利用率的同时,采取合理调水、因地制宜配水、改革灌溉制度、加强节水新技术推广应用等对策。 相似文献
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S Zgheib M C Gromaire C Lorgeoux M Saad G Chebbo 《Water science and technology》2008,57(11):1705-1712
The important organic pollution of combined wet weather flows (WWF), its acute impact on receiving waters have been widely demonstrated. The main three possibly origins for this organic pollution are: runoff water (streets and roofs), wastewater and erosion of sewer sediments in combined sewer system. This work, for tracing the origin of organic particles bound in combined sewer system, has been focused on the innovative use of sterols. So, eight sterols have been selected and analysed for each kind of sample. Results are represented in contents of sterols (microg g(-1)) and in sterol profiles (%).The comparison of contents and profiles leads the separation between two groups: runoff water, characterized by the total absence of coprostanol, epicoprostanol and coprostanone, and the group of sewer deposits (gross bed sediment (GBS), organic layer (OL), biofilms) and wastewater. Moreover, sewer deposits and wastewater can be distinguished by their sterol contents and profiles. To evaluate their contribution to WWF a comparison between sterol signatures is done which shows that these effluents have a strong similarity in profiles and in contents of sterols to the organic layer. 相似文献
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M. Menenti J. Chambouleyron J. Morábito L. Fornero L. Stefanini 《Water Resources Management》1992,6(3):185-199
A new approach on the functioning of an irrigation scheme has been presented. A mathematical representation of the irrigation system based on measured system properties, such as losses due to percolation and to poor management, in only a part of the system is used. This mathematical representation is termed an equivalent irrigation network. The merit of this approach is that it reduces the number of required streamflow measurements.When water amounts are measured for a number of paths in the irrigation network, so-called path efficiencies are obtained. The path efficiency is a measure of the amount of water lost along the way. The numerical model that simulates the operation of the irrigation system is based on the path efficiencies. This simulation model in turn is used to calculate different objective functions, corresponding with different optimization goals, like uniform water distribution, minimum groundwater extraction, minimum cost of water supply.This paper gives the theoretical background of the approach. The application to an actual irrigation scheme will be discussed in a second paper. 相似文献