供水管网震后流量监测点的动态分级优化布局研究

为了提高管网地震监测点布局的准确性和合理性，基于管网微观水力计算模型和动态分级法，提出供水管网震后流量监测点的动态分级优化布局模型。首先，利用管网微观水力计算模型计算管段流量的影响系数，构建管段的影响系数矩阵，并利用信息熵确定管段权重；其次，标准化处理影响系数矩阵，通过聚类迭代提出供水管网地震流量监测点优化布局的动态分级方法，对供水管网震后流量监测点进行优化布置分级评定；最后，根据工程实例进行方法实践，结果表明:供水管网中的管线分类较为科学合理，地震监测点在供水管网上分布也比较均匀，而且该模型在一定程度上消除了人为因素的影响，保障了震时管网的监控效果和日常建设的合理性。     

山西省绿色转型发展现状评价及路径研究

从经济、社会、资源、环境保护4个层面构建了切合山西省实际情况的绿色转型发展指标体系,采用熵权法及聚类分析方法对山西省的绿色转型发展现状进行了评价,根据评价结果,结合政策背景,提出了山西省实现绿色转型发展的路径,以实现山西省均衡快速的绿色转型发展。     

河湖水环境问题及管理和治理模式

本文首先介绍了我国当前的河湖水环境现状,分析了我国水资源存在的一系列问题,主要问题包括水体污染和富营养化;河湖面积严重萎缩,河湖水的功能逐渐退化;难以降解的有机污染物污染量加大。有针对性地提出了改善我国河湖水环境的管理以及治理模式,进一步落实了保护河湖水环境工作,加强水资源周围生态环境的文明建设,实现河湖水环境的可持续发展。     

基于生态分区的我国湖泊营养盐控制目标研究

为更好地控制我国湖泊的富营养化水平,在五大湖泊生态分区的基础上,对不同生态分区的100个湖泊总氮(TN)、总磷(TP)、TN/TP与叶绿素a(Chl-a)的关系进行了分析,进而提出了不同生态分区的湖泊营养盐控制目标.结果表明,五大湖泊生态分区中,东北湖区富营养化水平最低,华北湖区富营养化水平最高,近几年五大湖区湖泊富营养水平呈上升趋势.从TN、TP对五大生态分区湖泊Chl-a浓度的影响看,TP是东北和华北湖区湖泊藻类生长的限制性营养盐,而TN和TP同时是中东部、云贵和蒙新湖区湖泊藻类生长的限制性营养盐.从TN/TP判断,在TN/TP<10的湖泊中,除华北湖区外的其他4个湖区湖泊Chl-a均受TN显著影响;TP仅对东北、蒙新湖区湖泊的Chl-a有显著影响.在TN/TP>17的湖泊中,除蒙新湖区外的其他4个湖区湖泊Chl-a均受TP显著影响,而在中东部、云贵和蒙新湖区,TN对Chl-a也有显著影响.在10相似文献   

新安江流域土地利用结构对水质的影响

以新安江上游流域为研究区域,用该流域2010年5月TM遥感影像图作为底图,通过实地野外调查获取了新安江流域的土地利用图.运用ArcGIS的水文、空间分析功能,将流域划分为8个子流域,并分析各子流域的土地利用结构.根据2010年1～12月的水质监测数据,分析TN、TP、高锰酸盐指数、NH4+-N、粪大肠菌群的时空变化特征,以及与土地利用结构之间的定量关系.结果表明,TN和NH4+-N有明显的时间变化特征,为枯时期>丰水期>平水期,而其他几种指标没有明显的时间变化.在空间上,整体上呈现出渔梁、浦口污染最为严重.流域内土地利用结构与水质之间的相关关系表现为:耕地、水体、建筑用地起源作用,林地、草地起汇作用.在年度上看,耕地对TN、NH4+-N、高锰酸盐指数影响最大,草地对TP影响最大;不同水期上,枯水期和丰水期,对各指标影响最大的土地利用类型为耕地,在平水期,对TN、TP、粪大肠菌群影响最大的土地利用类型分别为耕地、草地、林地.     

南岔湖夏季浮游植物初报

对2013年夏季南岔湖的浮游植物进行了初步研究,共鉴定初浮游植物6门,8纲,13目,24科,43属,共94个分类单位。其中优势种6种。南岔湖水体属于中污染。     

陈家大院泡湖泊湿地植物多样性研究

研究陈家大院泡湖泊湿地植物多样性规律对于改善大庆市萨尔图区的生态环境,了解物种群落丰富度具有重要意义.通过野外样地调查,分析了陈家大院泡湖泊湿地植物群落组成,并计算了植物群落多样性特征指数,包括Margalef指数,Simpson指数,Shannon-wiener指数和Pielou均匀度指数,结果表明,研究区湖泊湿地共有38种植物,分别隶属于18科34属,除榆树为木本植物外,有36种草本植物以及1种藓类植物.经数据处理后得出,每个样方平均含有3个物种,植株个体数目平均为115,Margalef指数平均值为0.567,Simpson指数平均值为0.814,Shannon-wiener指数平均值为0.313,Pielou均匀度指数平均值为0.267.由此看出,陈家大院泡湖泊湿地植物多样性水平较低,植物群落组成较为单一,生态环境脆弱.     

Fast increasing of surface ozone concentrations in Pearl River Delta characterized by a regional air quality monitoring network during 2006-2011

Based on the observation by a Regional Air Quality Monitoring Network including 16 monitoring stations, temporal and spatial variations of ozone(O3), NO2and total oxidant(Ox) were analyzed by both linear regression and cluster analysis. A fast increase of regional O3concentrations of 0.86 ppbV/yr was found for the annual averaged values from 2006 to 2011 in Guangdong, China. Such fast O3increase is accompanied by a correspondingly fast NOx reduction as indicated by a fast NO2 reduction rate of 0.61 ppbV/yr. Based on a cluster analysis, the monitoring stations were classified into two major categories – rural stations(non-urban) and suburban/urban stations. The O3concentrations at rural stations were relatively conserved while those at suburban/urban stations showed a fast increase rate of 2.0 ppbV/yr accompanied by a NO2 reduction rate of 1.2 ppbV/yr. Moreover, a rapid increase of the averaged O3 concentrations in springtime(13%/yr referred to 2006 level) was observed, which may result from the increase of solar duration, reduction of precipitation in Guangdong and transport from Eastern Central China. Application of smog production algorithm showed that the photochemical O3production is mainly volatile organic compounds(VOC)-controlled. However, the photochemical O3production is sensitive to both NOx and VOC for O3pollution episode. Accordingly, it is expected that a combined NOx and VOC reduction will be helpful for the reduction of the O3 pollution episodes in Pearl River Delta while stringent VOC emission control is in general required for the regional O3 pollution control.     

Beyond hypoxia：Occurrence and characteristics of black blooms due to the decomposition of the submerged plant Potamogeton crispus in a shallow lake

Organic matter-induced black blooms(hypoxia and an offensive odor) are a serious ecosystem disasters that have occurred in some large eutrophic shallow lakes in China. In this study, we investigated two separate black blooms that were induced by Potamogeton crispus in Lake Taihu, China. The main physical and chemical characteristics, including color- and odor-related substances, of the black blooms were analyzed. The black blooms were characterized by low dissolved oxygen concentration(close to 0 mg/L), low oxidation-reduction potential, and relatively low pH of overlying water. Notably higher Fe2+and∑S2-were found in the black-bloom waters than in waters not affected by black blooms. The black color of the water may be attributable to the high concentration of these elements, as black FeS was considered to be the main substance causing the black color of blooms in freshwater lakes. Volatile organic sulfur compounds, including dimethyl sulfide, dimethyl disulfide, and dimethyl trisulfide, were very abundant in the black-bloom waters. The massive anoxic degradation of dead Potamogeton crispus plants released dimethyl sulfide, dimethyl disulfide, and dimethyl trisulfide, which were the main odor-causing compounds in the black blooms. The black blooms also induced an increase in ammonium nitrogen and soluble reactive phosphorus levels in the overlying waters. This extreme phenomenon not only heavily influenced the original lake ecosystem but also greatly changed the cycling of Fe, S, and nutrients in the water column.     

基于实测数据与遥感影像的鄱阳湖水体光学分类

鄱阳湖是我国最大的淡水湖泊,受季风气候影响其水体空间动态变化大,且广阔的水域内部差异也较大,因此湖泊水体光学分类对反演湖泊水质参数及监测湖泊水质有着重要意义。以鄱阳湖为研究区,根据实测的反射光谱数据形态特征将鄱阳湖的水体分为4类:特别浑浊、中等浑浊、轻度浑浊和清水区,并分别对每一类结果进行分析。考虑到实测光谱数据局限于湖区某些离散点的情况,不足以观测整个鄱阳湖区域内所有不同水体类型的空间分布和动态变化,从而将该方法利用于遥感影像以便观测整个湖区水体类型。在Landsat OLI遥感影像上任意选取采样点,根据其波谱形态建立基于斜率的分类算法,并应用决策树模型把鄱阳湖水体分为5类:特别浑浊、中等浑浊、轻度浑浊、清水区和特别清澈,影像的分类结果图与实地考察的情况相一致。把模型应用于其他时期的遥感影像进行鄱阳湖水体分类,对比影像的分类结果图表明:2002、2005和2009年鄱阳湖区分别出现3种、4种和4种不同的水体类型,且水体浑浊范围呈现出动态变化。研究表明水体光学类型分类可以更好的监测湖泊水质的时空变异性。