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基于2018—2021年太湖地区哨兵2号(Sentinel-2)卫星遥感影像和随机森林算法,结合植被敏感指数,开展太湖水生植被分布监测,综合分析了水生植被的时空变化特征,初步揭示了太湖水生植被的动态变化。结果表明,太湖水生植被分布面积有逐年上升的趋势,且年间变化具有明显的单峰型特征,表现为春季沉寂,夏季快速增长,秋季达到暴发期,冬季面积开始减退;太湖水生植被主要分布于东太湖、东部沿岸和贡湖,类型以沉水植被为主,其中浮叶植被主要分布于东太湖,挺水植被主要分布于东太湖沿岸的浅水区域;沉水植被主要分布于东部沿岸和贡湖;水生植被主要分布的东太湖水域,其水质总体优于太湖其他水域。 相似文献
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太湖氮磷大气干湿沉降时空特征 总被引:6,自引:0,他引:6
为了探索太湖氮磷营养盐干湿沉降特征及对太湖营养盐输入的贡献,于2011年不同季节采集太湖不同位点的大气干湿沉降样品,分析干湿沉降中氮(N)和磷(P)的形态和沉降量。研究结果表明,输入太湖的磷以干沉降为主,而氮以湿沉降为主。在太湖干沉降中总无机氮(TIN)占总氮(TN)的77.1%,溶解性磷(DIP)占总磷(TP)的77.9%。干沉降中TIN主要以NH+4-N为主。西太湖是TN与TP通过大气干湿沉降输入太湖的最高湖区。太湖全年大气TN沉降总量为20 978 t,TP沉降总量为1 268 t,因此,氮磷大气干湿沉降是太湖营养盐输入的重要来源之一。 相似文献
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对无锡太湖治理工作进行了总结和回顾,指出目前太湖“藻型生境条件”尚未根本改变,湖体中蓝藻数量仍处于较高水平且随时有大面积暴发的可能,太湖治理将是一项长期的系统性工作。针对太湖基础性研究相对滞后制约科学治太工作推进的问题,提出必须加强“太湖总氮来源及控制措施”“太湖蓝藻水华成因及控制措施”“太湖纳污能力”“太湖水生态修复方法”等7项重点基础性研究的建议。 相似文献
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以2005年以后太湖无锡区域底质为研究对象,分析了太湖底泥中重金属的含量分布及富集状况,采用地积累指数法和潜在生态危害指数法对重金属的生态危害进行评价。结果表明:太湖无锡区域底质受重金属轻度污染,含量高于全国水系沉积物平均值;地积累指数法显示太湖无锡区域底质中重金属污染排序为Cu=As〉Pb〉Zn〉Cr〉Cd〉Hg;金属对太湖无锡区域底质构成的潜在生态危害由强到弱为Hg〉Cu〉As〉Cd〉Pb〉Cr〉Zn;从区域上看,2种评价方法均表明底质中重金属危害程度为宜兴沿岸区〉梅梁湖〉五里湖〉贡湖无锡水域。 相似文献
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李旭文 《环境监测管理与技术》2009,21(3):54-57
利用互联网上USGS提供的公益性Landsat-7SLC—OFFETM遥感数据下载服务,建立了太湖地区2003年-2008年ETM遥感影像数据库,开展蓝藻水华面积解译和暴发特征分析。统计结果表明,2007年和2008年太湖蓝藻水华暴发呈加剧态势。 相似文献
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近日,二艘机动渔船满载着1.5万kg河蚌和1万kg螺蛳,在二艘渔政快艇的引导下,缓缓驶入了紧偎浩瀚太湖的西五里湖,由渔政人员和渔民开始向五里湖投放贝类,标志着无锡市太湖“净水渔业”项目正式启动。 相似文献
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典型湖泊水华特征及相关影响因素分析 总被引:1,自引:0,他引:1
通过2011-2015年对太湖、巢湖和滇池水华高发季节的连续监测,以藻类密度和水华面积为判据评价了3个湖体的水华情况及变化趋势,探讨了水华发生的主要影响因素。结果表明:太湖水华程度以"轻度水华"为主,巢湖水华程度以"轻微水华"为主,滇池水华程度以"中度水华"为主;太湖、巢湖和滇池水华规模均以"零星性水华"为主;太湖和巢湖藻类密度与水温、pH、溶解氧、总氮、总磷和高锰酸盐指数均呈显著正相关,与透明度呈显著负相关,与氨氮无显著相关性;滇池藻类密度与水温、总磷和高锰酸盐指数均呈显著正相关,与透明度和氨氮呈显著负相关,与pH、溶解氧和总氮无显著相关性。 相似文献
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不同水动力条件对景观水体富营养化模拟过程中藻类演替的影响 总被引:3,自引:0,他引:3
采用微宇宙培养法,分析了不同水动力条件(不循环、水循环和泥循环)对微污染景观水体富营养化模拟过程中藻类演替的影响.结果表明,水循环和泥循环使得水体的TP值前期增加后期减少,前期藻类生长主要受TP影响,而后期浊度成了重要的影响因素;水循环引起的TP值减少及蓝藻聚集状态的破坏,导致了藻类的生长明显减缓,但优势种的演化过程却... 相似文献
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Biju A. George Hector M. Malano Ahmad Raza Khan Anju Gaur Brian Davidson 《Environmental Modeling and Assessment》2009,14(6):691-704
To keep pace with population and economic growth, the city of Hyderabad, India, will need to identify and develop new supply
sources almost continually. Increasing population growth rate, declining surface water resources, overexploitation of groundwater,
deterioration of ground water quality and poor sewage treatment are the major water-related issues in Hyderabad. This paper
reviews the current situation facing policy makers who need to come to terms with the problem of restricted water supply and
increasing demand in an urban centre such as Hyderabad, India. The City Water Balance model developed in this study can be
used to analyse different scenarios that include water conservation, urban wastewater reuse and improvement of distribution
and conveyance efficiency. Water conservation programs, which include a 5% conveyance efficiency improvement, reusing 90 million
cubic metres (MCM) of urban runoff and adoption of water harvesting by 0.5 million households together with recycling 120
MCM of wastewater recycling wastewater would be sufficient to meet the water demand by 2031, if the population grows at a
rate of 2.5%. 相似文献
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This study focused on the development and application of the new approach 'Total Maximum Daily Load (TMDL) based sustainable basin growth and management strategy' to give better insight for the management of surface waters. The establishment of the proposed decision process mainly comprised: beneficial use designations-targets, interrogation of the ambient water quality, selection of variable(s) for TMDL analysis, water quality modeling, basin growth scenarios development and decision on the basin growth plan. The approach was validated through a systematic application study in a field case in Turkey, known as Tahtali Basin. Results revealed that decision process assists policy makers to develop realistic strategies that take into account the basin specific conditions. 相似文献
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Risk assessment and loading capacity of reclaimed wastewater to be reused for agricultural irrigation 总被引:1,自引:0,他引:1
Chiou RJ 《Environmental monitoring and assessment》2008,142(1-3):255-262
The reuse of treated municipal wastewater should be one of the new water resource target areas. The suitability of the reuse of wastewater for agricultural irrigation has to consider health risk, soil contamination and the influence of the reclaimed water on crop growth. In this work the aim is to use quantitative risk analysis to assess the health effects related to reclaimed water quality and to calculate the loading capacity of reclaimed wastewater in terms of the heavy metal accumulation. The results of chemical risk assessment show there would be slightly significant health risk and what risk there is can be limited within an acceptable level. The following exposure pathway: reclaimed water-->surface water-->fish (shellfish)-->human, and arsenic risks are of more concern. In terms of reuse impact in soil contamination, the most possible heavy metal caused accumulation is arsenic. The irrigative quantity has to reach 13,300 m(3)/ha to cause arsenic accumulation. However, only 12,000 m(3)/ha is essential for rice paddy cropland. The high total nitrogen of reclaimed water from secondary treatment makes it unfavorable for crop growth. The recommended dilution ratio is 50% during the growth period and 25% during the maturity period. 相似文献
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Bacteria play a significant role in water contamination. Chemicals are mostly used for the treatment of bacteriologically contaminated water. The use of bacterial interactions is a new approach to limit the pathogens' growth. Detection of antimicrobial substances produced by lactic acid bacteria against the waterborne pathogens is the objective of this work. Microbiological and biochemical methods were used to identify lactic acid bacteria having an antimicrobial activity. Evaluation of antimicrobial activity with growth kinetic measurements was performed. Four isolates of lactic acid bacteria obtained from whey and curd were identified. The predominant species belonging to the Lactobacillus genera are: Lactobacillus rhamnosus, Lactobacillus sakei, Lactobacillus paracasei, and Lactobacillus paraplantarum. The present study revealed that the Lactobacillus consortium is able to inhibit Staphylococcus aureus's growth along with Escherichia coli and Vibrio species. In mixed culture, after 24?h, the Lactobacillus consortium reduces the growth of S. aureus by 2.03 log; moreover, the growth of the latter bacteria totally ceased after 72?h of incubation. The protein produced by the Lactobacillus consortium was responsible for arresting the growth of S. aureus. 相似文献
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In this paper, a novel approach of modelling time series of nitrate concentrations in drinking water by nonlinear growth functions is proposed. An almost constant increase in the average values of nitrate concentrations occurred at the Vinokov??ak wellfield in the county of Vara?din, Croatia, in the period between 1998 and 2013. Our hypothesis was that the time series would be well adjusted to the nonlinear growth function with asymptotic properties after smoothing performed by the moving average method. We used a general growth model which does not have asymptotic properties and the logistic, Gompertz and Richards functions which do have asymptotic properties. Last three growth functions were modified based on the knowledge of a constant presence of basic nitrate concentrations in the drinking water before growth. The fit of growth curves to experimental data was assessed using R 2 and Aikake’s information criterion. The modified growth functions gave the best fit to the smoothed time series of nitrate concentrations with R 2 ranging from 0.9960 to 0.9986. 相似文献
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The aim of the work was to study the influence of the water taken from one of the most polluted parts of the Peter the Great
Bay (the Japan Sea), the Nakhodka Bay, on the growth and chlorophyll a concentration in the cells of microalga P. tricornutum Bohlin (Bacillariophyta). The estimation of the dynamics of cell number growth and chlorophyll a concentration in the cells
of microalga grown in the water from the Nakhodka Bay was made. At the same time, in 2007–2008, the main hydrochemical parameters,
such as water salinity, dissolved oxygen concentration, BOD5, organic and mineral phosphates concentration, anionic surfactants, and total petroleum hydrocarbons, were determined. It
is shown that in July 2007, when most hydrochemical parameters were lower than the maximum permissible level, the culture
growth and chlorophyll a contents in the cells did not differ from the control for certain. In other seasons these indices
differed greatly from the control. The positive correlation between the concentration of dissolved oxygen, phosphates, petroleum
hydrocarbons, and the number of microalga cells, grown in the water from the Nakhodka Bay, was shown. 相似文献
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以常州市典型城市黑臭水体神童浜为对象,采用小球藻和大型溞作为急性毒性测试手段,对整治前、后神童浜4个点位的上覆水和孔隙水的毒性效应进行了对比和评价。结果表明,整治后神童浜上覆水水质明显改善;上覆水在整治前、后对小球藻生长均无抑制作用,反而呈促进作用;对黑臭水体的整治降低了上覆水和孔隙水的生物毒性,但整治后的上覆水仍存在富营养化问题,且孔隙水对水生生物仍具有一定的毒性风险。提出,利用生物毒性测试能反映出黑臭水体整治前、后的毒性变化,可应用于对黑臭水体整治效果的评价。 相似文献