首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到19条相似文献,搜索用时 125 毫秒
1.
舒金华 《湖泊科学》1993,5(3):261-268
本文在湖水自净能力研究的基础上,根据我国“水污染防治法”和排放水污染物许可证制度的要求,结合各地湖泊污染的实际情况,提出了制订湖泊水污染物排放标准的技术原则、工作程序和计算方法。并附有不同类型湖泊排放标准计算实例,可供各地湖泊管理部门在制订地方水污染物排放标准中参考选用。  相似文献   

2.
城市化对湖泊和港湾环境的影响   总被引:3,自引:0,他引:3  
全球经济的发展必然经历工业化和城市化,在城市化过程中,不可避免地产生工业和生活垃圾,这些垃圾不仅污染土地,也污染河流和湖泊,特别在湖泊和港湾中,由于水流速度变缓,污染物容易随着沉积物沉淀下来,又由于气候变化和人类活动,湖泊和港湾的沉积物会再次释放污染物而污染水体,这些污染物主要是过量的氮、磷、有毒有机物和重金属,由于经济和人文环境的不同,在不同地区污染程度有差异,目前,在发展中国家较为严重,针对这些污染人们用机械的、化学的和生物的方法来治理湖泊和港湾的污染,但根本上要从源头控制污染-减少污染物的排放。  相似文献   

3.
邹锐  吴桢  赵磊  陈异晖  余艳红  刘永 《湖泊科学》2017,29(4):819-826
湖泊氮、磷通量是表征湖泊营养状态的重要指标,也是探究湖泊富营养化机制的重要途径.通过氮、磷通量的计算和质量平衡关系的分析,可以识别出在湖泊富营养化过程中起关键作用的过程.以三维水动力-水质模型为计算平台,模拟湖泊水动力、水质的动态过程,并以模拟结果为基础核算湖泊氮、磷循环通量及其在氮、磷循环整体中的贡献,识别湖泊氮、磷循环关键源汇过程的变化规律.滇池是我国富营养化湖泊的代表,同时其半封闭特性为营养物质循环提供了更为稳定的环境,以滇池为案例,基于前期校正和验证过的滇池水动力-水质模型来分析循环通量计算方法的适用性.结果发现,研究年度内滇池外海总氮的年总输入量(包括外源和内源)为7620.92 t,总输出量(包括出流、反硝化和沉降)为7637.31 t;总磷的年总输入量为(包括外源和内源)450.23 t,总输出量(包括出流和沉降)为429.57 t,其中陆域输入是最主要的氮、磷输入途径,而反硝化和沉降则是主要的输出过程.相较于传统的质量平衡方法,通过三维模型计算所得的营养盐通量平衡结果能更好地揭示湖体内所发生的氮、磷转化过程.  相似文献   

4.
王魏根 《湖泊科学》2018,30(5):1368-1378
周转(一个集合体中的物种在另一个集合体中被其他物种代替)和嵌套(物种贫乏的集合体是物种丰富集合体的严格子集)是形成β多样性的两种途径.本文采用Baselga提出的β多样性加法分解方法,对云南高原湖泊软体动物β多样性及其周转和嵌套组分进行了研究.利用多位点方法计算,结果表明云南高原湖泊软体动物总β多样性为0.8903(S?rensen指数法)和0.9419(Jaccard指数法),周转组分分别占总β多样性的80.93%(S?rensen指数法)和88.92%(Jaccard指数法).总β多样性为瓣鳃类腹足类,金沙江水系南盘江水系澜沧江水系元江水系,浅水型深水型.周转组分占总β多样性的比例为瓣鳃类腹足类,元江水系南盘江水系澜沧江水系金沙江水系,深水型浅水型.采用配对的方法计算结果表明,不同湖泊对软体动物总β多样性及其周转、嵌套成分的值分布形式不同.周转的成分分布比较均匀,嵌套成分呈现一种单峰的分布.周转成分最大值为1,最小值为0,表明湖泊对间β多样性存在着完全的周转和完全的嵌套形式,所以相应地要采取多区域保护和重点保护相结合的策略保护云南高原湖泊软体动物.  相似文献   

5.
樊贤璐  徐国宾 《湖泊科学》2018,30(5):1225-1234
本文首先运用频度分析法构建湖泊生态系统健康评价指标体系;其次,应用变异系数法与信息熵权法相结合的组合赋权法计算指标权重;在此基础上提出了基于生态—社会服务功能协调发展度的湖泊生态系统健康评价方法,并给出从湖泊综合发展水平和湖泊协调发展度两方面度量湖泊生态系统健康水平的等级划分标准.应用此评价方法,以白洋淀生态系统为研究对象,开展其健康状况及协调发展状况的模型实证研究.结果显示:白洋淀生态系统综合发展水平处于不健康病态萎缩状态,湖泊协调发展度属于临界协调发展.该方法综合考虑了生态完整性和社会服务功能两个方面的协调性和发展性进行湖泊健康评价,从协调、发展的角度为湖泊管理建设提供建议.同时研究表明协调发展度湖泊健康评价法具有计算简单、适用性强的特点,同样适用于其他湖泊健康评价.  相似文献   

6.
青藏高原腹地半混合型湖泊的发现及其意义   总被引:2,自引:1,他引:2  
发现青藏高原腹地的兹格塘错湖(海拔4560 m)是一个半混合型湖泊. 分析表明, 湖盆地形的屏障因素是导致半混合现象的主要原因, 淡水入流的作用次之. 作为目前世界上发现的海拔最高的半混合型湖泊, 兹格塘错湖对世界湖泊系统分类研究具有一定意义, 同时为开展湖泊现代过程及纹泥应用研究提供了可能.  相似文献   

7.
基于经验频率曲线的湖泊富营养化随机评价方法及其验证   总被引:9,自引:1,他引:9  
谢平  黎红秋  叶爱中 《湖泊科学》2004,16(4):371-376
本文提出了基于经验频率曲线的湖泊富营养化随机评价方法.该法通过建立水体富营养化评价标准中各项水质指标和评价级别的经验频率曲线,推求实际水体各项水质指标的经验频率,并采用加权平均法推求湖泊富营养化评价级别的经验频率,从而得出湖泊富营养化的评价级别,具有方法简单、图形直观、计算工作量小的特点.经全国30个湖库湖泊实测水质资料的验证,随机评价方法与模糊评价方法和灰色评价方法的计算精度相当.  相似文献   

8.
湖泊沉积物-水界面营养盐释放是研究湖泊环境行为的重点关注对象,但目前对于湖泊通量的估算方法选择缺乏横向定量比较.以南京莫愁湖为研究对象,在冬春夏3季采用静态释放培养法、机械搅拌培养法、流动培养法和间隙水浓度扩散模型法4种常见的湖泊通量培养方法进行氮磷释放对比实验.结果表明,非扩散模型法(静态释放、机械搅拌、流动培养)在冬季存在负通量,随着气温升高,夏季通量估算值为正,且该3种方法通量数值差异不显著.间隙水扩散模型法在三季实验中结果数值无负值,对比非扩散模型组具有显著差异,约低一个数量级.不同方法在培育过程中溶解氧和pH变化差异显著,流动培养法最为稳定.4种方法的通量结果在不同季节变化趋势具有显著相关性,非扩散模型法估算结果作为表观通量值,适用于计算湖泊沉积物营养盐释放总量,其中静态释放法结果稳定性较差,平行组相对标准偏差最高达70%;流动培养法稳定性最好,平行组相对标准偏差最高仅21%.扩散模型法估算结果作为理论释放值,在估算浅水湖泊通量时低于实际释放通量,适于探究深水湖泊沉积物间隙水动态释放过程,有助于分析湖泊沉积物性质.不同培养方法,有其侧重点,根据不同湖泊状况,应选取合适方法进行通量估算.  相似文献   

9.
适宜的生态水位能够反映湖区生态系统的多种需求,是湖泊长期稳定健康运转的基本保障. 目前湖泊适宜生态水位的推求大多侧重恢复天然水位情势. 然而过水型湖泊承担着防洪、供水、航运等多种功能,频繁的人类活动导致湖泊水位情势异常复杂. 同时随着社会经济的快速发展,水质恶化对过水型湖泊生态系统造成了较大的负面影响,仅恢复天然水位情势难以反映过水型湖泊的生态需求. 因此,在IHA-RVA法的基础上,本文针对过水型湖泊吞吐性强的特点,利用水质-水位二元响应关系系统地提出了一套逐月修正过水型湖泊适宜生态水位阈值,并确定适宜水位变动率的方法. 以洪泽湖为应用实例,结果表明:1)根据湖泊水文情势和入湖污染物变化情况,湖泊调度周期可以划分为平水期(1—4月)、泄水期(5—6月)、蓄水前期(7—9月)和蓄水后期(10—12月);2)各时期内,洪泽湖水位和水质呈现较强的相关性,其中平水期、泄水期和蓄水后期水质均随着水位上升而下降,平均Pearson系数达-0.77,仅在蓄水前期水质随水位上升而改善;3)现阶段洪泽湖的自净能力和污染物滞留比例竞争关系激烈,逐月适宜生态水位阈值为:12.92~12.99、12.79~12.99、12.84~12.99、12.86~12.99、12.71~12.89、12.39~12.63、11.97~12.93、12.50~13.07、12.65~13.26、12.90~13.04、12.90~13.04、12.90~13.04 m,除蓄水前期外,基于水位水质关系修正的适宜生态水位范围较IHA-RVA法计算的天然水位范围缩小了73.4 %. 总体而言,基于本文方法设计的湖泊适宜生态水位不仅可以满足生态系统对于水体大小的需求,一定程度上也可以体现湖泊生态系统对于水质的要求,为洪泽湖等过水型湖泊的生态调度、水资源管理提供科学依据.  相似文献   

10.
吴坚 《湖泊科学》1991,3(1):74-81
我国湖泊众多, 极为丰富的湖泊资源在水产、水利、航运、旅游、水屯等国有经济中占有重要地位。湖泊资源的开发与环境保护和预测正受到广泛关注。随着计算机和计算数学的发展, 数值模拟方法被广泛应用于大气、海洋、湖泊或水库等研究中, 数值模拟方法就是借助于计算机, 对基于一定的观测事实和数学物理方法建立的数学模式进行数位计算, 从而对自然过程进行模拟和预测的方法, 它使得湖泊学研究从定性和定进客观分析到定量模拟和预 测, 目前, 它是解决许多复杂的湖泊环境课题不可缺少的一种有力手段。本文评述的重点放在动力学研究方向。  相似文献   

11.
 Volcanic lakes have a wide range of characteristics, and we make an attempt to delineate the limiting physical conditions for several lake classes. The ratio between heat input and heat dissipation capacity of a lake constrains the temperature for perfectly mixed steady-state volcanic lakes. Poorly mixed lakes are also conditioned by this ratio, but their temperature structure is also strongly influenced by the hydrodynamics resulting from different mechanisms of heat transfer. The steady-state temperatures of volcanic lakes are largely determined by the magnitude of the volcanic heat influx relative to the surface area of the lake. Small lakes have only a small capacity for heat dissipation and their temperature rises quickly with only small heat inputs; large lakes are buffered against variations in heat input. Both the heat dissipation and meteoric water input into a lake are functions of lake surface area and therefore each lake water temperature demands a certain precipitation rate for mass conservation, independent of lake size. The results of energy/mass-balance modeling shows that under common atmospheric conditions, most steady-state volcanic lakes are unlikely to maintain a temperature in excess of 45–50  °C. Validation of the volcanic lake model was performed using published data from Yugama Lake (Japan) and the Keli Mutu lakes (Indonesia). Also, the model was applied to 24 natural systems to provide a baseline assessment of energy fluxes under the model assumptions so future work on those systems can identify nuances in individual systems that deviate from the simple model conditions. We recommend the model for use in assessing temperature variations and volcanic lake stability in settings with known physical and atmospheric conditions. Application of the energy/mass balance calculations of model lakes provides a genetic classification scheme largely based on physical process parameters. Received: 28 February 1996 / Accepted: 23 November 1996  相似文献   

12.
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   

13.
The numerous lakes on the Tibetan Plateau play an important role in the regional hydrological cycle and water resources, but systematic observations of the lake water balance are scarce on the Tibetan Plateau. Here, we present a detailed study on the water cycle of Cona Lake, at the headwaters of the Nujiang‐Salween River, based on 3 years (2011–2013) of observations of δ18O and δ2H, including samples from precipitation, lake water, and outlet surface water. Short‐term atmospheric water vapor was also sampled for isotope analyses. The δ2H–δ18O relationship in lake water (δ2H = 6.67δ18O ? 20.37) differed from that of local precipitation (δ2H = 8.29δ18O + 12.50), and the deuterium excess (d‐excess) in the lake water (?7.5‰) was significantly lower than in local precipitation (10.7‰), indicating an evaporative isotope enrichment in lake water. The ratio of evaporation to inflow (E /I ) of the lake water was calculated using both d‐excess and δ18O. The E /I ratios of Cona lake ranged from 0.24 to 0.27 during the 3 years. Observations of atmospheric water vapor isotopic composition (δ A ) improved the accuracy in E /I ratio estimate over a simple precipitation equilibrium model, though a correction factor method provided nearly identical estimates of E /I ratio. The work demonstrates the feasibility of d‐excess in the study of the water cycle for lakes in other regions of the world and provides recommendations on sampling strategies for accurate calculations of E /I ratio.  相似文献   

14.
底泥疏浚能控制湖泊富营养化吗?   总被引:135,自引:20,他引:115  
世界上许多湖泊面临着严峻的富营养化问题,富营养化湖泊底泥中的营养盐比水体中要丰富得多,因此,人们常把疏浚底泥作为治理富营养化湖泊的一种重要措施,它需要巨大的资金投入,但尚未见在中等以上湖泊中通过疏浚底控制湖泊富营养化的明显实例,分析 浚底泥作为水利工程和航道工程措施有重要效用,其改善水质效果与疏浚方法有关,适当的疏浚可在短期内改善水质,但从月和季以上长期段持,疏浚底泥不是控制湖泊富营营养化的充要条  相似文献   

15.
Interactions between lakes and groundwater are of increasing concern for freshwater environmental management but are often poorly characterized. Groundwater inflow to lakes, even at low rates, has proven to be a key in both lake nutrient balances and in determining lake vulnerability to pollution. Although difficult to measure using standard hydrometric methods, significant insight into groundwater–lake interactions has been acquired by studies applying geochemical tracers. However, the use of simple steady‐state, well‐mixed models, and the lack of characterization of lake spatiotemporal variability remain important sources of uncertainty, preventing the characterization of the entire lake hydrological cycle, particularly during ice‐covered periods. In this study, a small groundwater‐connected lake was monitored to determine the annual dynamics of the natural tracers, water stable isotopes and radon‐222, through the implementation of a comprehensive sampling strategy. A multilayer mass balance model was found outperform a well‐mixed, one‐layer model in terms of quantifying groundwater fluxes and their temporal evolution, as well as characterizing vertical differences. Water stable isotopes and radon‐222 were found to provide complementary information on the lake water budget. Radon‐222 has a short response time, and highlights rapid and transient increases in groundwater inflow, but requires a thorough characterization of groundwater radon‐222 activity. Water stable isotopes follow the hydrological cycle of the lake closely and highlight periods when the lake budget is dominated by evaporation versus groundwater inflow, but continuous monitoring of local meteorological parameters is required. Careful compilation of tracer evolution throughout the water column and over the entire year is also very informative. The developed models, which are suitable for detailed, site‐specific studies, allow the quantification of groundwater inflow and internal dynamics during both ice‐free and ice‐covered periods, providing an improved tool for understanding the annual water cycle of lakes.  相似文献   

16.
湖泊热力结构不仅影响湖泊内部生态环境,而且与区域气象和气候系统相互影响,但目前对湖泊垂直温度的观测研究仍非常匮乏.本研究基于青藏高原拉昂错连续的湖温和气象观测,分析了小时尺度和日尺度热力分层规律和混合层深度的变化特征.结果表明:拉昂错为冷多次完全混合型湖泊;湖表温度8月达到最大值,湖面敞水区和沿岸的湖表温度季节震荡相同,但存在一定的空间差异;与空气温度相比,湖表温度变幅小,降温更慢,峰值滞后约1个月.同时发现,拉昂错混合层深度变化较为规律,辐射和风速是影响湖泊混合层深度的主要外界因子.探明真实的高原湖泊分层规律,有利于提高湖泊模拟能力,为优化湖泊参数化方案提供参考.  相似文献   

17.
梁新歌  王涵  赵爽  宋春桥 《湖泊科学》2023,35(6):2111-2122
在全球气候变暖和极端气候事件增加的背景下,流域水文循环过程受到的影响越来越强烈,导致湖泊水位变化表现出复杂的时空特征。而泛北极地区是地球上湖泊数量与面积分布最为集中的区域之一,该地区湖泊对气候变化响应非常敏感。因此,了解这些湖泊近期水文变化特征十分必要。本研究共搜集了36个泛北极大型湖泊(>500 km2)基于遥感或站点观测的近20年水位数据,分析其时空变化特征。本文使用线性回归模型来估算湖泊水位的变化趋势,进而利用皮尔逊相关分析了其主要水文影响变量和大气环流机制,并运用Mann-Kendall突变检验法探讨了水位突变的原因。结果表明,泛北极湖泊的水位整体上呈现不同程度上升(平均速率为0.013 m/a),有23个(64%)湖泊的水位呈上升趋势;研究湖泊中有10个通过90%统计显著性检验。其中,水位上升速率最大的湖泊是位于哈萨克斯坦的腾吉兹湖,上升速率为0.078 m/a。泛北极湖泊水位的波动主要与径流有关,有19个(53%)湖泊的水位波动与径流的增加更为相关;相比而言,位于亚洲的极地湖泊水位的上升与流域蒸发的降低显著相关,尤其是库苏古尔湖。从区域大气环流影响来看,泛北极湖泊水位变化主要与厄尔尼诺-南方涛动有关,其次是北极涛动和北大西洋涛动。本研究有助于加深对泛北极湖泊近20年水位变化规律及气候影响特征的科学理解。  相似文献   

18.
“十三五”时期,长江流域水环境质量改善明显,但湖泊水质和富营养化状况改善滞后. 长江中游作为我国淡水湖泊集中分布区域之一,部分湖泊存在水环境质量恶化和富营养化加重问题. 本文以长江中游区域国家开展监测的洪湖、斧头湖、梁子湖、大通湖、洞庭湖和鄱阳湖这6个典型湖泊为研究对象,科学评价其2016—2020年水质和富营养化时空变化特征及关键驱动因素,探讨其成因及治理对策. 结果表明,“十三五”时期长江中游湖泊水质和富营养化程度存在较大差异,与2016年相比,2020年大通湖水质改善最为明显,梁子湖水质变差,总磷是影响长江中游湖泊水质类别的主要因子; 洪湖富营养程度恶化最为严重,斧头湖次之,TLI(SD)对长江中游湖泊富营养化评价贡献最大. 目前长江中游湖泊呈有机污染加重和叶绿素a浓度升高现象,洪湖、斧头湖和梁子湖主要与氮、磷营养盐浓度升高有关,而大通湖、洞庭湖和鄱阳湖受水文过程、流域纳污量和湖泊管理等非营养盐因素影响较大. 总氮和总磷仍然是影响“十三五”时期长江中游湖泊水质和富营养化的最主要驱动力,且各湖泊总氮和总磷浓度变化均具有较强正相关性,建议开展河湖氮、磷标准衔接工作,提出河湖氮、磷标准限值或考核目标,以完善河湖水环境质量标准和生态健康影响评价技术规范. 同时,建议长江中游湖泊在开展截污控源、内源控制和生态修复的同时,进一步深化流域管理,特别是对洞庭湖、鄱阳湖、梁子湖和斧头湖等跨行政区湖泊,以提高湖泊治理与修复的系统性和整体性.  相似文献   

19.
Cyanobacterial dominance in lakes has received much attention in the past because of the great success and frequent bloom formation in lakes of higher trophic levels. In this paper underlying mechanism of cyanobacterial dominance are analyzed and discussed using both original and literature data from various shallow mixed and deep stratifying lakes from temperate and (subtropical regions. Examples include all four ecotypes of cyanobacteria sensu MUR et al. (1993), because their behavior in the water column is entirely different.Colony forming species (Microcystis) are exemplified from the large shallow Lake Taihu, China. Data from a shallow urban lake, Alte Donau in Austria are used to characterize well mixed species (Cylindrospermopsis) while stratifying species (Planktothrix) are analyzed from the deep alpine lake Mondsee. Nitrogen fixing species (Aphanizomenon) are typified from a shallow river-run lake in Germany.Factors causing the dominance of one or the other group are discussed as well as consequences for restoration measures. Existing knowledge on cyanobacterial dominance is summarized.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号