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931.
稠油采出水回用热采锅炉供水的处理工艺设计   总被引:3,自引:0,他引:3  
运用混凝沉降、溶气浮选、粗精过滤和弱酸软化方法对稠油采出水进行深度处理。可达到热采锅炉用水指标 ,回用热采锅炉供水 ;生产装置产生的污水、污油、污泥均回收利用。笔者总结了流程选择、工艺配置、新工艺的采用、工艺及自控设计特点 ,为今后污水处理设计提供借鉴。  相似文献   
932.
分指数分级评分叠加法在水质评价中的应用   总被引:1,自引:0,他引:1  
提出了一种新的具有明确物理意义、且计算简单的“分指数分级评分叠加法”,讨论了该方法评价的表示方法,并给出了应用实例。  相似文献   
933.
特征分析方法在江河水质评价中的应用   总被引:7,自引:0,他引:7  
本文着重介绍了特征分析方法的理论模型,并把该模型具体地运用到了吉林省江河水质评价中,依据其分析结果,对我省的江河水质污染程度进行了分级划分,相信对江河治理会起到一定的指导作用。  相似文献   
934.
水资源经济价值影响因素的分析   总被引:1,自引:1,他引:0  
从自然、经济、社会和水环境4个方面定性分析了其对水资源经济价值的影响,并就这些因素所涵盖的主要量化指标实证分析了我国31个省市自治区水资源的经济价值,进而对如何提高水资源经济价值提出了若干建议,旨在促进水资源的可持续发展与利用,以及人与自然的和谐发展。  相似文献   
935.
东莞市近岸海域水环境质量评价及变化趋势分析   总被引:1,自引:0,他引:1  
采用污染分担率法确定污染因子,应用综合污染指数法对2004~2009年东莞市近岸海域水环境质量进行全面评价,并运用秩相关系数法分析其变化趋势。结果表明:CODMn、磷酸盐、无机氮、汞是影响东莞近岸海域水环境质量的主要因子;东莞市近岸海域水环境质量由上游到下游基本呈现依次下降的特征;从2004~2009年,近岸海域环境质量总体呈现好转的态势。  相似文献   
936.
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.  相似文献   
937.
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.  相似文献   
938.
Evans et al. (Journal of Agricultural and Environmental Ethics, 2008) have attempted to enmesh me in their dispute with the Florida Bureau of Invasive Plant Management about a specific system, Kings Bay/Crystal River. In so doing, they repeatedly mischaracterize my positions in order to depict, incorrectly, invasion biology as monolithic and me as a representative of one extreme of a false dichotomy about management of introduced species. In addition, they introduce an issue irrelevant in this case (extinctions) and cite incorrect data. Proposing to manage people, manatees, introduced plants, and cyanobacteria in Kings Bay by participative adaptive management, they ignore the fact that living organisms can both disperse autonomously and hitchhike. Finally, they present few details on any aspect of their management proposal and do not address the myriad problems that have beset previous attempts at scientific adaptive management, especially at large scales. Until such a management approach is fleshed out and implemented, it is impossible to assess its validity for Kings Bay, and it is very premature to suggest it as a general model for dealing with invasive species disputes.  相似文献   
939.
Abstract: Impact of watershed subdivision and soil data resolution on Soil Water Assessment Tool (SWAT) model calibration and parameter uncertainty is investigated by creating 24 different watershed model configurations for two study areas in northern Indiana. SWAT autocalibration tool is used to calibrate 14 parameters for simulating seven years of daily streamflow records. Calibrated parameter sets are found to be different for all 24 watershed configurations, however in terms of calibrated model output, their effect is minimal. In some cases, autocalibration is followed by manual calibration to correct for low flows, which were underestimated during autocalibration. In addition to normal validation using four years of streamflow data for each calibrated parameter set, cross‐validation (using a calibrated parameter set from one model configuration to validate observations using another configuration) is performed to investigate the effect of different model configurations on streamflow prediction. Results show that streamflow output during cross‐validation is not affected, thus highlighting the non‐unique nature of calibrated parameters in hydrologic modeling. Finally, parameter uncertainty is investigated by extracting good parameter sets during the autocalibration process. Parameter uncertainty analysis suggests that significant parameters show very narrow range of uncertainty across different watershed configurations compared with nonsignificant parameters. Results from recalibration of some configurations using only six significant parameters were comparable to that from calibration using 14 parameters, suggesting that including fewer significant parameters could reduce the uncertainty arising from model parameters, and also expedite the calibration process.  相似文献   
940.
Our recent paper advocating adaptive management of invasive nonnative species (INS) in Kings Bay, Florida received detailed responses from both Daniel Simberloff, a prominent invasion biologist, and Mark Sagoff, a prominent critic of invasion biology. Simberloff offers several significant lines of criticism that compel detailed rebuttals, and, as such, most of this reply is dedicated to this purpose. Ultimately, we find it quite significant that Simberloff, despite his other stated objections to our paper, apparently agrees with our argument that proposals for alternative management of established INS (i.e., alternatives to minimization/eradication) should not be rejected on an a␣priori basis. We argue that more specific development and application of adaptive approaches toward INS management, whether in Kings Bay or other appropriate case studies, would be facilitated if ecosystem managers and invasion biologists follow Simberloff’s lead on this key point. While Sagoff largely shares (and, indeed, served as a primary source for developing) our general arguments that challenge common moral and scientific assumptions associated with invasion biology, he does question our suggestion that participatory adaptive management provides an appropriate framework for approaching environmental problems in which science and politics are inherently entangled. We attempt to answer this criticism through a brief sketch of what participatory adaptive management might look like for Kings Bay and how such an approach would differ from past management approaches.  相似文献   
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