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11.
对苏州河氨化菌进行了生态调查,并对其进行了生理生化分析。研究结果表明,苏州河水体中氨化菌数量普遍较高,上游至下游氨化菌数量逐步增多。赵屯至北新泾5个断面之间的差异很小,均在104个/mL左右,浙江路桥和武宁路桥的氨化菌数量要比上游的5个断面高出1个数量级。苏州河下游武宁路桥和浙江路桥断面水体中全年氨化菌数量季节变化较大。氯化菌的数量与水体中总氮和氨氮成正比,与硝酸盐成反比。  相似文献   
12.
沉积物中磷负荷及其释放对水质的影响   总被引:6,自引:0,他引:6  
以华东师范大学校河为研究对象,通过野调研与室内模拟实验相结合,研究了校河沉积物中磷负荷量,释放量与释放速度以及温度和水体扰动对其影响,并探讨了沉积物中磷释放对校河水质的影响,为校河的富营养化防治提供科学依据。  相似文献   
13.
苏州河底泥的耗氧量   总被引:5,自引:3,他引:5  
对苏州河底泥耗氧量(SOD)的实验测定结果表明,苏州河底泥(北新泾下游)的夏季耗氧强度是冬季的6倍,最大强度发生在武宁路河段,达7500mg/m2  相似文献   
14.
ABSTRACT: As part of a study of Redwood National Park in north-western California, an investigation was conducted from June to November 1974 on intragravel dissolved oxygen and sediment in three tributaries to Redwood Creek, a major coastal stream that flows through Redwood National Park. Of concern was whether the intragravel environment of streams in logged and unlogged redwood-forested drainage basins was different. The tributary in the unlogged drainage basin had lower percentages of fine streambed sediment than either of the tributaries in logged drainage basins. Concentration and percentage saturation of dissolved oxygen of intragravel water were highest in the stream in the unlogged drainage basin, intermediate in the stream in the patch-cut drainage basin, and lowest in the stream in the clear-cut drainage basin. The differences in intragravel dissolved-oxygen conditions among the three tributaries are attributed chiefly to differences in their interchange of surface and intragravel water. The larger quantities of fine streambed sediment in the two streams in logged basins may have reduced the permeability of the streambeds and hence their capacity to interchange surface and intragravel water. However, differences in the lithology of the three tributary drainage basins examined may contribute to the differences in the percentage of fine sediments observed among the streams, even in the absence of logging.  相似文献   
15.
The Central Niger Delta is made up of a network of rivers and creeks that constitute the inland surface waters. These surface waters have historically influenced settlement patterns and are of diverse use to residents of the Central Niger Delta. Surface water like many ecological system are complex, whose complexity has been associated with seasonal variability. Traditional knowledge (TK), traditional ecological knowledge (TEK) and the traditional eco-livelihood knowledge (TELK) of residents of four rural communities in the Central Niger Delta have been explored in developing a river use profile of rural communities of the Central Niger Delta. A questionnaire survey has been carried out in four communities, two each from the Otuoke and Kolo Creeks. The result shows that river use varies across seasons and affected by: physico-chemical water quality and characteristics of surface water; the hydrological characteristics; the biological/ecological characteristics; cultural use and demand; need for development projects; and access to this vital resource. Fishing constitute one of the major livelihood source in the Central Niger Delta and the TELK of fishers in the sample communities have specifically been explored to understanding fishing patterns across seasons. The five seasons identified from this study are: flood season; flood recession season; dry season; early rainy season; and rainy season. Therefore, the thesis of this paper is that there is the need to balance the current usage of surface water in the developing world such as the Central Niger Delta with the demand for development as well as future use if development is to meet the criteria for equitable development. The river use profile could be a promising tool in planning for equitable development.
M. D. SmithEmail:
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16.
苏州河浮游植物群落结构特征   总被引:2,自引:0,他引:2  
以正在生态恢复进行中的苏州河水体为研究对象,共设黄渡、华漕、北新泾、武宁路桥、长寿路桥和浙江路桥6个采样点,从2000年10月至2002年10月间按春、夏、秋、冬进行了9次采样,另外,在黄渡、华漕和武宁路桥于2002年的5月和6月增加了5次采样,对苏州河浮游植物群落的种类组成和数量特征进行了调查研究,结果表明:苏州河浮游植物的平均个体数达到了 4.7×106 ind/L,细胞密度平均值为 10.2×106 ind/L,生物量均值为 5.73 mg/L。苏州河浮游植物群落结构的定性和定量组分表达均显示绿藻优势,其密度和生物量分别为 5.774 ind/μL 和 2.159 mg/L;属数、种数和生物量结构以硅藻次之。生物量、个体数与细胞数的Shannon Weaver指数均值分别为3.05、3.22和3.28;生物量、个体数与细胞数的Pielou均匀度指数均值则分别为0.73、0.76和0.77,Margalef和Simposon指数均值分别为1.59和0.84.  相似文献   
17.
Different sources of pollution in Karasu Creek were investigated to obtain the water quality and ratio of contamination in this region. To achieve the main objectives of the present study, water samples were collected from Karasu Creek, starting from flow pattern at the upstream site of Akkaya Dam to the end of the dam, crossing the place where the Creek drains into. Dissolved oxygen, electrical conductivity, temperature and maximum/minimum pH were measured systematically for 12 months in the stations, where the water samples were collected. Chemical analyses of the water samples were carried out by using Cadas 50 S brand UV spectrometer to find out the Pb, Fe, Cu, Zn, Ni, Cr, Cd, S, F and Cn concentrations. These concentration were determined in μg/lt as 80–850; 180–4,920; 10–6,100; 440–25,530; 130–2,400; 120–280; 20–150; 214,250–1,113,580; 1,560–4,270 and 40–690, respectively. To determine metal levels of the water samples, multivariate analyses (element coefficient correlation, coefficient correlation dendrogram, hierarchical cluster analysis dendrogram, model summary and ANOVA) were used. The analyses yielded highly accurate results. There were positive correlations between some elements and their possible sources were the same. The stations which resembled each other along the creek were divided into three groups. The water quality of the creek was low and had toxic qualities. Eutrophication developed in Akkaya Dam along the creek. The source of pollution was thought to be industrial and residential wastes. Absolute (0–100 m), short distance (100–500 m) and medium distance (500–2,000 m) conservation areas should be determined in pollution areas along Karasu Creek and they should be improved.  相似文献   
18.
基于ArcView的空间型苏州河环境信息系统原型研究   总被引:2,自引:0,他引:2  
根据流域污染源调查的大量第一手资料,依据GIS开发设计中原型法的思想,以结构化系统分析为主要技术路线,以ArcView为主要软件平台,采用面向对象的编程语言Avenue所开发的苏州河环境综合整治管理信息系统,探讨了系统开发中的主要技术问题,包括确立系统开发的构想与目标、系统分析与设计、系统开发、系统应用等。笔者认为,流域环境管理信息系统的建立将为苏州河环境综合整治的规划与管理提供高效、科学的信息支持,从而提高规划与管理的水平。   相似文献   
19.
Non-structural streambank stabilization, or bioengineering, is a common stream restoration practice used to slow streambank erosion, but its ecological effects have rarely been assessed. We surveyed bank habitat and sampled bank macroinvertebrates at four bioengineered sites, an unrestored site, and a comparatively less-impacted reference site in the urban Peachtree-Nancy Creek catchment in Atlanta, GA, USA. The amount of organic bank habitat (wood and roots) was much higher at the reference site and three of the bioengineered sites than at the unrestored site or the other bioengineered site, where a very different bioengineering technique was used (“joint planting”). At all sites, we saw a high abundance of pollution-tolerant taxa, especially chironomids and oligochaetes, and a low richness and diversity of the bank macroinvertebrate community. Total biomass, insect biomass, and non-chironomid insect biomass were highest at the reference site and two of the bioengineered sites (p < 0.05). Higher biomass and abundance were found on organic habitats (wood and roots) versus inorganic habitats (mud, sand, and rock) across all sites. Percent organic bank habitat at each site proved to be strongly positively correlated with many factors, including taxon richness, total biomass, and shredder biomass. These results suggest that bioengineered bank stabilization can have positive effects on bank habitat and macroinvertebrate communities in urban streams, but it cannot completely mitigate the impacts of urbanization.  相似文献   
20.
曝气对生物促生剂修复城市黑臭河道水体的影响   总被引:3,自引:0,他引:3  
在实验室条件下研究了曝气对生物促生剂修复城市黑臭河道水体效果的影响,并通过控制曝气时间及强度考察处理效果以确定曝气方式和曝气量。结果表明:在生物促生剂修复城市河道黑臭水体过程中使用曝气协同作用可大大增强生物促生剂的修复作用,加快修复速度。使用间歇曝气协同生物促生剂作用时效果与连续曝气相近,且可以降低运行成本。实验60d后,上覆水COD、NH3-N和TP去除率分别达46.8%、98.7%和73.3%,上覆水pH由7.61提高至7.92;底泥削减达5.49cm,底泥有机质削减率达10.5%。  相似文献   
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