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北京城市湖泊富营养化评价与分析 总被引：24，自引：1，他引：23
根据2006年对北京市区不同功能重点湖泊水体进行的逐月监测,采用综合营养状态指数法,对湖泊富营养化现状进行了评价。结果表明,水源湖泊目前处于中营养状态,但在夏秋季由于温度和光照等气象条件的影响,可接近轻富营养;重要景观湖泊处于轻一中度富营养;一般景观湖泊处于中度一重度富营养状态。湖泊富营养程度随季节变化明显：盛夏和初秋形成高峰,冬、春季最低,总磷、总氮含量与叶绿素a呈显著正相关关系,尤其总磷与叶绿素a的相关性更加显著。由于城市排水管网不健全,雨污分流不彻底,暴雨期大量溢流生活污水直接向湖泊补水河道中排放;湖泊补水沿线降雨径流产生的非点源污染较严重;加上污水处理厂再生水水质较差,加重了补给湖泊富营养程度。 相似文献
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目前,我国湖泊富营养化及蓝藻水华问题十分突出,国家高度重视湖泊的生态环境保护.自“九五”以来,国家就投入太湖、巢湖、滇池“老三湖”等重污染湖泊的治理,但成本巨大,且历经近30年才初见成效.按照湖泊污染程度,湖泊治理与保护可分为“污染治理型”“防治结合型”“生态保育型”3大类.“老三湖”的治理是典型的“先污染、后治理”的模式,水质较好湖泊主要属于生态保育型湖泊,因此,“老三湖”治理模式不适用于水质较好湖泊的保护.本文系统总结了我国水质较好湖泊优先保护理念的形成和水质较好湖泊专项实施的历程.根据水质较好湖泊的特点,及其生态系统退化与修复的一般过程,提出了水质较好湖泊保护的基本思路.从热力学角度,阐明了氮磷营养盐输入湖泊生态系统中是熵增过程,也是湖泊生态系统退化的根本原因,湖泊氮磷污染负荷源头控制是关键.湖泊流域生态安全格局是确保湖泊生态系统健康的基础,从景观生态学角度,阐明了优化湖泊流域水土资源利用、优化发展模式是减轻湖泊环境压力的重要途径.在浅水湖泊生态系统,以沉水植物占优势的“清水态”和以浮游植物占优势的“浊水态”转换过程不是沿着同一条途径,存在上临界阈值和下临界阈值,水生态修复过程表现出一种迟滞的现象.从湖泊水生态系统稳态转换理论角度,阐明了湖泊生态修复工程应在湖泊生态系统发生退化转变之前实施,才能获得较高的环境效益.通过国家财政专项对81个水质较好湖泊的支持,既能促进湖泊流域经济社会发展,又能确保湖泊水环境质量变好,湖泊水生态系统逐步改善.建议加强不同类型湖泊保护模式的总结,深入对水质较好湖泊生态系统演替理论和保护技术研究,支撑国家系统开展水质较好湖泊保护. 相似文献
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Pit lakes of the Central German lignite mining district: Creation, morphometry and water quality aspects 总被引：1，自引：0，他引：1
About 140 pit lakes exist in Central Germany. These have resulted from lignite mining and are important parts of the post-mining landscape in the Central German lignite mining district. Their water quality is mainly influenced by the consequences of pyrite oxidation, i.e., acidification or results of natural or artificial neutralization. The major way of filling as well as a cheap and successful measure against acidification was the diversion of river water into the lakes or their filling with neutral water from mines still operating. Eutrophication, contamination by industrial pollutants and infection with pathogens imported with river water were found to be unimportant threats for the pit lakes in the Central German lignite mining district. Intrusion of naturally saline groundwater from deeper underground resulted in some cases in elevated concentrations of sodium chloride and in meromixis. The diverse uses of the lakes (e.g. recreation, nature conservation, water management) indicate that the pit lakes fulfil widely the typical functions of lakes in a landscape. The creation, the current state of water quality and lessons learned in water quality management are reported upon for the pit lakes of the Central German lignite mining district. 相似文献
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Differences and cause analysis of changes in lakes of different supply types in the north‐western Tibetan Plateau 
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下载免费PDF全文 Most lakes of the Tibetan Plateau were experiencing quick expansion in recent decades; a detailed study on the changes in lakes of different supply types will help to understand the cause of the changes by analysing area change of 34 lakes and water level change of eight lakes in the north‐western Tibetan Plateau. All lakes are classified into three types: non‐glacier‐fed lakes, upstream lakes and glacier‐fed lakes. The glacier‐fed lakes are separated into glacier‐fed_P1 (quick expansion region) and glacier‐fed_P2 (slow expansion region). Combining the changes in precipitation, temperature and evaporation, less precipitation may be the main reason for lake shrinkage from 1976 to 1996 and quickly increasing precipitation led to the lakes' expansion from 1996 to 2000. However, after 2000, upstream lakes remained in a stable state with slight variation, non‐glacier‐fed lakes and glacier‐fed_P2 lakes exhibited a slightly increasing rate with high precipitation and high evaporation, and glacier‐fed_P1 lakes still expanded quickly. On the basis of the assumption of same precipitation and evaporation, glacial meltwater may make an important contribution (>52%) to the increase in water storage of Bangdag Co and Meima Co. The results suggest that glacial meltwater augments the increased rate of glacier‐fed_P2 lakes and plays a much more important role in the expansion of glacier‐fed_P1 lakes compared to other lakes. 相似文献
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In Finland a great number of forest lakes are affected by silvicultural practices such as logging. Logging affects water chemistry and thus the ecological state of lakes by causing nutrient loads and increasing erosion and humic substances in water. Water quality assessment requires definition of natural background conditions and ecological status of water bodies. Therefore it is necessary to determine the impact of these practices on aquatic organisms. In the absence of long-term monitoring data, paleolimnological methods provide a powerful tool for determining human-induced changes in lakes. In this study diatom assemblages, diatom-inferred water total phosphorus and total organic carbon, and sediment chemistry were analyzed from the sediments of six lakes with a logged catchment area (11-53%). According to one-way analysis of similarities (ANOSIM) the diatom communities of three lakes were different before, immediately after and more than 10 years after logging and diatom assemblages in remaining three lakes did not show statistically significant differences between these times. However, all changes were minor, and at present the diatom assemblages and diatom-inferred water chemistry of all the lakes are close to the pre-logging conditions. The minor alterations are probably due to the wide protective zones around the lakes. 相似文献
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Tracing contributions to hydro‐isotopic differences between two adjacent lakes in the southern Tibetan Plateau 下载免费PDF全文
下载免费PDF全文 Hydrological processes of lakes in the Tibetan Plateau are an important indicator of climate change. Due to the high elevation, inaccessibility and limited availability of historical observations, water budget evaluation of typical lake basins has been inadequate. In this study, stable isotopes are used to trace the multiple water sources contributing to two adjacent lakes on the north slope of the Himalayas, Gongmo‐tso and Drem‐tso. The two lakes have nearly the same elevation, lake area and climatic condition. However, the isotopic composition of the two lakes presents significant differences. Qualitative observations attribute the differences to hydrological discrepancies: Gongmo‐tso is a through‐flow lake, whereas Drem‐tso is a terminal lake. Quantitative analyses, including water and isotope mass balance modelling, clarify the fluxes and isotopic compositions among the various hydrological elements. The isotopic composition of input water, calculated as the summation of rainfall and upstream runoff, is estimated using the local meteoric water line (LMWL) combined with the time series of lake water isotope values. The isotopic composition of evaporation is calculated with a linear resistance model using local meteorological data. The results show that Drem‐tso is a closed lake in a hydrological steady state with relatively more enriched lake water isotope values resulting mainly from evaporation. In contrast, through‐flow accounts for more than 88% of the water input into Gongmo‐tso. The large amount of upstream runoff with lower isotopic composition and enrichment due to evaporation are the major contributions to the observed lake water isotope values. Isotopic modelling of the two neighbouring lakes is effective for isotopic and hydrological research in this region with limited in situ observations. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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Effects of Watershed Land Use and Lake Morphometry on the Trophic State of Chinese Lakes: Implications for Eutrophication Control 总被引：1，自引：0，他引：1
Water quality in lakes is influenced by a large number of watershed and lake characteristics. In this study, we examined the relative effects of watershed land use and lake morphology on the trophic state of 19 lakes in the Yunnan plateau and lower Yangtze floodplain, the two most eutrophic regions in China. Trophic state parameters consisted of total nitrogen, total phosphorus, chemical oxygen demand, chlorophyll‐a, Secchi depth, and trophic state index, while lake morphometric variables included area, maximum depth, mean depth, water residence time (WRT), volume, and length to width ratio. Percentages of forest, grassland, cropland, unused land, built‐up land, and water body in each lake's watershed were extracted from a land use map interpreted from Landsat TM images. A t‐test indicated that lower Yangtze floodplain lakes were shallower and had higher percentages of cropland and built‐up land in watersheds than Yunnan plateau lakes. Pearson's correlation analysis indicated that both watershed land use and lake morphometric variables were significantly related to most of the trophic state parameters. However, stepwise regression analyses demonstrated that the trophic state of the lower Yangtze floodplain lakes was mainly controlled by the percentages of cropland and built‐up land in watersheds, while that of Yunnan plateau lakes was mostly determined by the lake depth and WRT. These results suggest that the relative effects of watershed land use and lake morphology on lake trophic state are dependent on the lake's location. This study can provide some useful information in watershed land use management for controlling eutrophication in Chinese lakes. 相似文献
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B. V. Adamovich T. V. Zhukova T. M. Mikheeva R. Z. Kovalevskaya E. V. Luk’yanova 《Water Resources》2016,43(5):809-817
Variations of the trophic status of lakes Batorino, Myastro, and Naroch were analyzed over a long period of 1978–2013. The lakes form a system of interconnected water bodies with a wide range of trophic states. In the period under consideration, the trophic conditions in the lakes varied from highly eutrophic (Lake Batorino) to oligotrophic (Lake Naroch), making it possible to analyze the long-term changes in the trophic state of the lakes with the use of different variants of evaluating the Carlson index (trophic state index, TSI), to assess the relationship between the three versions of the index with one another, with phytoplankton biomass, and with hydroecological characteristics, such as the concentrations of total N, seston, and organic matter and biochemical oxygen demand. The possibility to evaluate the index by other characteristics, including phytoplankton biomass, was also considered. 相似文献
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云贵高原湖泊水质现状及演变 总被引：16，自引：6，他引：10
利用2008年云贵高原13个湖泊丰水期的全面水质调查数据,系统分析云贵高原湖泊水质现状,通过与历史资料对比,揭示20年来的水质变化,并分析水质变化的原因.同时利用主成分分析将23个水质参数概括为6个主要成分,除程海外所有湖泊水质均与第一主成分密切相关.人类活动影响下的水体富营养化、有机污染以及农业面源污染等是除程海外湖泊污染的主要驱动因子,程海水质变化主要受水体的矿化度增加所驱动.另外,根据各主成分得分,本文也对13个湖泊水质进行了综合评价,并在评价的基础上就湖泊的保护和治理提出建议. 相似文献
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《Limnologica》2017
Temperate and tropical shallow lakes differ in several fundamental aspects with respect to management of eutrophication. High altitude tropical shallow lakes are a special case, showing similarities with temperate and tropical lakes. We studied the ecology of the eutrophic high-altitude tropical lake Yahuarcocha in the Ecuadorian Andes and evaluated the potential of biomanipulation to control eutrophication. With a toxin-producing Cylindrospermopsis bloom, low Secchi depth and low submerged macrophyte cover, Yahuarcocha is clearly in a turbid ecosystem state. Relatively low nutrient concentrations should theoretically allow for a shift to a clear water state through biomanipulation. Top-down control of phytoplankton by zooplankton, however, is complicated by the (1) absence of predatory fish, (2) fish community dominated by small poecelid species, (3) lack of a refuge for zooplankton from fish predation within the macrophytes, and (4) persistent, grazing resistant bloom of the cyanobacterium Cylindrospermopsis. In these aspects, lake Yahuarcocha is more similar to tropical shallow lakes, probably because water temperature is high relative to the mean air temperature and because of the absence of a cold season. The fish and macrophyte communities consisted almost entirely of exotic species. The exotic fish species probably stabilized the turbid state in the lake. 相似文献
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全球变化下青藏高原湖泊在地表水循环中的作用 总被引：2，自引：2，他引：0
青藏高原是地球上最重要的高海拔地区之一,对全球变化具有敏感响应.青藏高原作为"亚洲水塔",其地表水资源及其变化对高原本身及周边地区的经济社会发展具有重要的影响.然而,在气候变暖的情况下,构成高原地表水资源的各个组分,如冰川、湖泊、河流、降水等水体的相变及其转化却鲜为人知.湖泊是青藏高原地表水体相变和水循环的关键环节.湖泊面积、水位和水量对西风和印度季风的降水变化非常敏感,但湖泊面积和水量变化在不同区域和时段的响应也不尽相同.湖泊水温对气候变暖具有明显响应,湖泊水温和水下温跃层深度的变化能够对水—气的热量交换具有明显影响,从而影响了区域蒸发和降水等水循环过程.由于湖泊水量增加,高原中部色林错地区湖泊盐度自1970s以来普遍下降.根据60多个湖泊实地监测建立的遥感反演模型研究发现,2000—2019年湖泊透明度普遍升高.对不同补给类型的大湖水量平衡监测发现,影响湖泊变化的气象和水文要素具有较大差异.在目前的暖湿气候条件下,青藏高原的湖泊将会持续扩张.为了深入认识湖泊变化在青藏高原区域水循环和气候变化中的作用,需要全面了解湖泊水量赋存及连续的时间序列变化,需要深入了解湖泊理化参数变化及对湖泊大气之间热量交换的影响,需要更多来自大湖流域的综合连续观测数据. 相似文献
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《Acta Geochimica》2021,(4)
Currently,lakes and artificial reservoirs are increasingly threatened by eutrophication,which is the result of the combined action of many natural and anthropogenic factors.In the past,the effect of nutrient load on the trophic state of water bodies has attracted much attention,while few studies have addressed the effect of hydrological characteristics.Therefore,to reveal the coupling effects of hydrological characteristics and nutrient load in sediments on the trophic state of water bodies,this study collected relevant data from 36 lakes and reservoirs across China.Pearson correlation analysis showed that trophic level index was positively and significantly correlated with nutrient load in sediments and hydraulic retention time,while it was negatively correlated with mean depth and hydraulic load.The principal component analysis showed that the nutrient load was the first major component that influenced the trophic state of water bodies,followed by the mean depth and hydraulic retention time.Eutrophication was prone to occur in water bodies with mean depth less than 7 m and hydraulic retention time greater than 14 d,and the trophic level index regression equation with hydrological characteristics and nutrient load in sediments was derived by multiple regression analysis.This study revealed that the trophic state of water bodies influenced by both nutrient load and hydrological characteristics.It provides a new idea to reduce the occurrence of eutrophication in reservoirs by using the artificial hydrological regulation capacity of reservoirs. 相似文献
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Vertical distribution of average annual temperature of water in lakes in the period of maximum water heating is analyzed as a function of zonal climatic factors and lake morphometry. Regression analysis is applied to hydrometeorological data on water temperature measurements at standard horizons made from 1958 to 1989 in 58 lakes in northwester Russia and eight lakes in Finland. The temperature of the top five-meter layer is found to depend mainly on the latitude. The major factors at a depth of 10 and lower are the lake morphometry and river water inflow. 相似文献
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气候变化对湖库水环境的潜在影响研究进展 总被引：4，自引：3，他引：1
本文着重归纳气候变化对湖库热力特性、冰期、溶解氧、营养盐、浮游植物和水生植物等方面的影响规律,探讨气候变化对湖库水环境潜在影响的区域差异,讨论现有研究方法的优缺点和发展前景.研究表明,气候变暖对湖库物理过程的影响最为显著;热带草原气候和温带海洋性气候对于气候变暖和降雨变化的响应较其他气候类型突出;气候变化对湖库水环境的影响效果具有两面性.通过分析各气候类型中气候变暖对磷水平的潜在影响差异表明,亚热带季风气候的湖库更可能受气候变暖的影响趋于富营养状态.在今后研究中,建议深入开展各气候类型中区域性气候变化对湖库水环境影响的实例研究. 相似文献
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Perturbations of the lake water balance, inputs of heavy metals to lakes, and intensifying fertilization of lakes through
input and accumulation of phosphorus—these three classes of phenomena are among the more important background processes in
lake restoration. Lake restoration consists of a series of measures animed at producing a homeostatic response of a lake system
to external perturbations. The success of its implementation is affected by the morphometric and edaphic parameters of different
types of lakes. The relationship between the volume (V) and mean-depth
of fresh-water lakes indicates a trend of
. Glacial lakes occuring on or near crystalline shields have relatively shallow depths, whereas volcanic lakes, rift valley
and deep valley lakes have relatively greater depths for the same volume. For saline lakes (21 lakes, V>1 km3) that undergo cycles of expansion and shrinkage, the V to
relationship is closer to power 1. Water residence times (τ) of small and big fresh-water lakes show a trend of τ approximately
linear in
or τ∝V0.3. Volcanic lakes and Maare have longer residence times in comparison to other lakes of similar volumes. For the major inorganic
chemical species and heavy metals, the regulatory upper-limit concentrations in drinking water in the USA and EEC are from
several times to more than 100 times higher than their concentrations in a global mean river water. Only three elements (Fe,
P, and Al) occur in river water at concentrations approaching such upper-limit recommendations. Rates of accumulation of phosphorus
in lake water and sediments, computed as the difference between input and ouflow removal rates for 23 fresh-water lakes, are
generally lower for lakes of longer water residence time. The rate of accumulation is a measure of homeostatic response of
the lake system to input load: it is equivalent to the rate of all the removal processes needed to maintain phosphorus concentration
in lake water at a steady state. 相似文献
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西藏湖泊水体中主要离子分布特征及其对区域气候变化的响应 总被引：3，自引：0，他引：3
于2009 2010年对西藏34个湖泊表层水体进行采样和水质参数测量,测试不同湖泊水体主要离子浓度,分析其分布特征和对区域气候变化的响应.研究表明,不同湖泊水体的主要离子浓度及其水质参数存在差异,西藏大部分湖泊离子浓度高于全国甚至全球湖泊平均水平.湖泊的水化学类型主要为氯化物型,少部分是硫酸盐型.西藏湖泊受强烈蒸发作用的影响,水化学类型从东南到西北依次为碳酸盐型-硫酸钠型-硫酸钾型-氯化物型.对比1990s前的研究发现,大部分湖泊水体的主要离子浓度较上世纪有所降低,且部分湖泊水化学类型也发生了变化,该变化反映了过去几十年来西藏湖泊水化学对区域气候变化的响应. 相似文献
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为探究“十三五”期间武汉市湖泊水质变化特征及规律,分析当前武汉市湖泊水环境的主要问题及成因,为武汉市水生态环境保护“十四五”规划提供科学支撑,以武汉市166个湖泊为研究对象,根据武汉市环境监测中心2015-2019年对各个湖泊的监测数据,采用水质综合污染指数、富营养化状态评价、动态度分析等方法,对武汉市湖泊水环境进行综合评价.结果表明：1）2015-2019年武汉市湖泊水质总体好转,2019年全市湖泊综合污染指数较2015年下降7.74%,多数湖泊营养状态呈现稳中向好趋势,但湖泊水质较难实现持续改善.2）武汉市湖泊主要超标污染物总磷、氨氮、化学需氧量和高锰酸盐指数平均质量浓度在2015-2019年间均呈下降趋势,但2019年有47%湖泊总磷浓度劣于Ⅳ类评价标准,磷元素是制约湖泊水质的主要因素.3）2015-2019年武汉市中心城区湖泊综合污染指数下降,湖泊富营养化状态好转,但青山北湖、南湖等湖泊综合污染指数较高,排口排污、底泥内源污染是影响中心城区湖泊水质的主要因素.新城区湖泊水质改善仍面临一定压力,东西湖水系重度富营养化湖泊数量增多,后湖水系湖泊综合污染指数上升,农业面源、工业生产对新城区湖泊水质影响较大,湖泊破碎化导致的自净能力降低也是影响湖泊水质的重要因素. 相似文献