城市浅水型湖泊底泥污染物释放过程模拟试验研究

通过对城市浅水型湖泊(以宁波东钱湖为例)疏浚后上层底泥污染物释放过程模拟试验研究,分析了环境因子对底泥污染物释放特性的影响及其原因,得出了上覆水营养盐水平、水温和扰动对底泥污染物释放的影响曲线.同时,说明了湖泊内源性有机污染源对湖泊水质存在着潜在的危险性,提出了疏浚施工期间的规避措施,为城市浅水型湖泊底泥疏浚和富营养化治理提供依据.     

基于模糊综合评价的流域社会经济活动对太湖生态影响评价研究

太湖是我国的五大淡水湖之一。太湖流域是我国经济最发达、水污染最严重的地区之一，正面临着严重的环境问题。随着太湖流域社会经济的发展，太湖流域生态环境将承受更大的压力。因此，分析人类社会经济活动对太湖流域生态的影响，对研究太湖生态环境具有重要意义。采用系统分析的方法，围绕流域人类社会经济活动对湖泊生态安全的影响，建立湖泊生态安全的评价指标体系，利用层次分析法计算各指标因子的权重。在此基础上，以太湖流域2005年和2006年相关数据为依据，以MATLAB为工具，根据模糊数学的原理，利用多级模糊综合评价的方法对太湖进行生态综合评价，确定流域社会经济活动对整个湖泊生态系统的影响。研究结果表明，3个重要指数得分高低顺序依次为：水体环境状态指数＞水体污染负荷指数＞社会经济压力指数;除了点源污染以外，面源污染也是太湖流域生态环境问题的重要根源。     

生态工业仿真系统经济增长与环境压力关系动态变化分析

运用系统动力学模型和结构分解分析模型,对2005—2020年南通经济技术开发区生态工业仿真系统进行经济增长与环境压力关系的时序变化分析,通过基于物质消耗和污染物排放表征的环境压力的影响程度分析,得出:(1)开发区实施生态工业战略后,由2种驱动因素产生的环境压力一直存在,但环境压力在后期都呈现了较快下降趋势。(2)由物质消耗类型影响产生的环境压力,最大的是劳动力投入因子类型,其次为水耗,后期能耗作用超过水耗因子;由污染物排放产生的环境压力主要为固体废物类型所致,COD产生的环境压力稍大于SO2。(3)土地因素对环境压力正效应的变化影响呈下降趋势,经济因素对环境压力增长有明显的正向效应,而且一直是开发区的主导增长因素,技术因素对环境压力的抑制效应在后期减弱;3种因素对环境压力的影响程度视污染物及物质消耗类型不同而有所差异。     

基于浮游植物完整性指数的阳澄湖生态健康状态评价

为探究在以中华绒螯蟹养殖为主的情况下阳澄湖浮游植物群落结构与湖泊生态系统健康状态,于2022年7月(夏)和12月(冬)进行2次浮游植物样品采集和水环境因子测定,构建浮游植物完整性指数(P-IBI)体系,评价阳澄湖健康状况。结果表明：P-IBI评价显示阳澄湖夏、冬季的健康状态分别为一般、健康状态;夏季健康状况从优至劣依次为东湖、西湖、中湖,冬季则为西湖、中湖、东湖。P-IBI与透明度、流速、硝态氮、总氮呈极显著正相关(P<0.01),与pH、水温、磷酸盐、叶绿素a和高锰酸盐指数呈极显著负相关(P<0.01)。水环境因子直接或间接驱动了浮游植物群落结构和生物完整性的变化。     

喀斯特城市新区土地利用时空演变及生态效应分析——以贵阳市观山湖区为例

通过揭示喀斯特城市新区土地利用和生态效应本质联系及变化趋势,基于转移矩阵、动态度模型、生态环境质量指数和生态贡献率,定量分析观山湖区2010—2020年土地利用动态变化特征及其生态效应。结果表明：(1)观山湖区以林地、耕地和建设用地为主要土地利用类型,10年来水田和旱地呈减少趋势,灌木林地和城镇用地面积增长最大,东部城镇用地逐年向西南方向扩张,耕地转出面积最大,2015—2020年综合土地利用动态度达到峰值(0.546%)。(2)生态系统服务功能因林地增加不断增强,土地覆被状况指数与生态环境质量呈正比关系。(3)旱地和其他林地向有林地转移是改善生态环境的主要原因,有林地向旱地、城镇用地转移是导致生态环境恶化的主要驱动因素,2010—2020年观山湖区整体生态效应呈良性发展。     

热力学理论在湖泊富营养化研究中的应用

本文在分析了生态系统进化的热力学理论（最大能量、最大功率、最大优势原理）的基础上，综述了能量、功率和优势值在国内外湖泊富营养化研究中的应用，说明生态系统进化的热力学理论为认识和研究复杂的湖泊生态系统提供了整体性的途径，并指出为把热力学理论有效地用于湖泊富营养化的研究而应加强的科研工作。     

太湖西岸水质变化趋势及主要驱动因子

基于2009—2015年太湖西岸10个监测断面的8个水质指标数据,采用季节性Kendall检验法对其指标的浓度变化趋势进行分析,并用主成分分析法结合相关分析评价历年水质状况,分析影响太湖西岸水质的主要驱动因子。结果表明:(1)2009—2015年太湖西岸COD下降趋势显著,DO非显著上升,电导率、高锰酸盐指数、BOD5、氨氮、TP和TN均表现为高度显著下降趋势。(2)主成分分析从原始信息中提取出两个主成分,共解释了73.645%的结果,分别代表水质氮磷营养盐和有机污染。综合得分表明,2009—2015年太湖西岸水质呈逐年改善趋势。水质污染在空间上表现为北部向南部递减的趋势。(3)相关分析表明,氨氮和COD是影响该区域水质的主要驱动因子。     

基于驱动力-压力-状态-影响-响应模型的粤港澳大湾区惠州海岸带生态安全评价分析

将海岸带复合生态系统作为一个整体,充分考虑海岸带生态风险形成机制和生态环境保护要求,识别影响海岸带生态安全的主要因素。基于驱动力-压力-状态-影响-响应(DPSIR)模型,将海岸带生态安全归纳为驱动力、压力、状态、影响、响应5个准则层,选取26个能够反映生态安全状况的因子来构建海岸带生态安全评价指标体系。对粤港澳大湾区惠州岸段两个沿海县(区)2007、2010、2013、2015、2016年的海岸带生态安全状况进行评价分析,结果表明:(1)惠东县这5年海岸带生态安全等级分别为预警(Ⅲ)、较安全(Ⅱ)、较危险(Ⅳ)、较安全(Ⅱ)、较安全(Ⅱ);大亚湾区海岸带生态安全等级分别为预警(Ⅲ)、预警(Ⅲ)、预警(Ⅲ)、较安全(Ⅱ)、较安全(Ⅱ)。(2)"十二五"规划所采取的环境保护和生态建设措施对惠州海岸带生态环境的改善发挥了重要作用。海岸带生态安全状况于2013年有明显恶化,说明生态环境保护应对措施及力度仍不足以抵消这一时期持续增加的生态环境压力,同时,海岸带生态环境对于响应措施的反应具有一定程度的滞后性。(3)影响惠州海岸带生态安全的主要原因有工业的发展及污染物排放、人类活动密集及人类对海洋区域的大规模开发利用、政府响应措施实施力度、自然和人为原因所造成的海洋灾害和损失。     

农药对藻类的生态毒理学研究Ⅰ:毒性效应

随着现代农业的发展,世界范围内使用的农药品种越来越多,用量不断增加。农药对非靶生物的影响以及农药残留导致环境污染,造成生态系统结构和功能的破坏,早已受到了国内外的广泛关注。有关农药对生态系统中消费者类群毒性效应的研究较多。近年来,农药对于生态系统初级生产者－ 藻类的毒性及其生态毒理学的研究倍受重视。大力开展这方面的研究对于深入了解农药在生态系统中的迁移、转化及整体生态效应以及农药的生态风险评价无疑具有重要的理论意义和应用价值。本文综述了近年来国内外有关农药对单种藻类和藻类群落的毒性效应,影响毒性的环境因子。     

太湖新港口河口水域生态系统脆弱性及修复的探讨

介绍了新港口河口水域生态系统脆弱性的主要表现并依据湖泊生态学和恢复生态学相关原理，对新港口河口水域生态系统脆弱性根源和特征进行分析，并提出相应修复建议。     

湖泊水生植物管理方案探讨

根据湖泊水生植物的分布面积及生物量差异,大致可以将湖泊分为水生植物过量生长、水生植物适度生长以及水生植物高度退化、消亡三大类型.对这3种湖泊进行了分析研究,分别拟订了具有针对性的湖泊水生植物管理方案,并提出了湖泊水生植物管理方案实施的前提条件和有效保障措施,对目前中国富营养化湖泊的治理,特别是水生植物恢复工程实施后的后续管理具有一定的借鉴意义.     

Methane emission from lakes

A physico-chemical model to describe methane and carbon dioxide emission from lakes was developed. The model describes the emission by diffusion, bubbles and plants. The intensity of the fluxes can be calculated either for total or particular emission in dependence on gas bubbles composition. It was found, that diffusional (Q) and bubble (J) fluxes depend on the methane molar ratio (X) in bubbles as follows: [formula: see text]. The model allows to estimate the role of the methane oxidation by atmospheric oxygen in the total methane flux. It was shown, that the methane oxidation does not influence much methane fluxes to the atmosphere for most of the experimentally observed situations.     

Mercury in fish in Swedish lakes

The aim of this work has been to try to obtain a picture of the past, present and future mercury situation in fish in Swedish lakes, to make an estimate of the number of lakes threatened by 'blacklisting', and to see if the data can be used to reveal anything about the impact of liming on the Hg content in pike. The register contains a broad set of data from 1456 lakes. The main results are as follows. Trend analyses indicate that the Hg content in 1-kg pike seems to increase with time. This is interesting since there has been a significant decrease in mercury emissions from Swedish industries during the last two decades. High Hg contents in 1-kg pike appear in a very characteristic pattern, linked to specific sources of Hg emission. The data indicate that old Swedish 'sins' are still causing a lot of problems. The factors governing the leakage of Hg from soils to water ought to be a very important topic for further studies. The Hg content in pike shows the highest correlation with the following parameters: Hg in surficial sediments, pH, distance from point source and water hardness, lake water alkalinity and conductivity, water retention time, size of drainage area and lake surface. A formula which provides the best possible degree of explanation (r2 = 0.78) has been derived. At present there are about 250 lakes 'blacklisted' in Sweden due to high Hg content in fish. Our data show that there are at least 9400 lakes that ought to be 'blacklisted' today. A successful liming operation will alter the chemical conditions in lakes and also decrease the Hg content in fish.     

Changes in the Chemistry of Small Irish lakes

A re-survey of acid-sensitive lakes in Ireland (initial survey 1997) was carried out during spring 2007 (n = 60). Since 1997, atmospheric emissions of sulfur dioxide and deposition of non-marine sulfate (SO₄ ²⁻) in Ireland have decreased by ~63 and 36%, respectively. Comparison of water chemistry between surveys showed significant decreases in the concentration of SO₄ ²⁻, non-marine SO₄ ²⁻, and non-marine base cations. In concert, alkalinity increased significantly; however, no change was observed in surface water pH and total aluminum. High inter-annual variability in sea salt inputs and increasing (albeit non-significant) dissolved organic carbon may have influenced the response of pH and total aluminum (as ~70% is organic aluminum). Despite their location on the western periphery of Europe, and dominant influence from Atlantic air masses, the repeat survey suggests that the chemistry of small Irish lakes has shown a significant response to reductions in air pollution driven primarily by the implementation of the Gothenburg Protocol under the UNECE Convention on Long-Range Transboundary Air Pollution.     

Bioaccumulation of decamethylcyclopentasiloxane in perch in Swedish lakes

Decamethylcyclopentasiloxane (D5), a high production volume chemical used in personal care products, enters the environment both via air and sewage treatment plant (STP) recipients. It has been found in fish, and there is concern that it may be a bioaccumulative substance. In this work D5 was analyzed in perch from six Swedish lakes that did not receive STP effluent, and in perch and sediment from six lakes that received STP effluent. In the lakes receiving the STP effluent, the D5 concentrations in sediment varied over three orders of magnitude and were correlated with the number of persons connected to the STP normalized to the surface area of the receiving body. In the lakes not receiving effluent, the D5 levels in perch were all below the LOQ, while D5 was above the LOQ in almost all perch from lakes that received effluent. The D5 concentrations in perch and sediment from the lakes receiving STP effluent were correlated. This shows that STP effluent is a much more important source of D5 to aquatic ecosystems than atmospheric deposition, and that the risk of adverse effects of D5 on aquatic life will be greatest in small recipients receiving large amounts of STP effluent. The bioaccumulation of D5 was compared to that of PCB 180 on the basis of multimedia bioaccumulation factors (mmBAFs), which describe the fraction of the contaminant present in the whole aquatic environment (i.e. water and surface sediment) that is transferred to the fish. In four of the six lakes the mmBAF of D5 was >0.3 of the mmBAF of PCB 180. Given that PCB 180 is a known highly bioaccumulative chemical, this indicates that the bioaccumulation of D5 in perch is considerable.     

Nutrient dynamics in shallow lakes of northern greece

GOAL, SCOPE, BACKGROUND: Shallow lakes display a number of features that set them apart from the more frequently studied deeper systems. The majority of lakes in Northern Greece are small to moderate in size with a relatively low depth and are considered as sites of high value of the wetland habitat. However, the water quality of these lakes has only been evaluated segmentally and occasionally. OBJECTIVE: The objectives of this study were to thoroughly investigate nitrogen and phosphorus speciation in lakes of a high ecological significance located in N. Greece, in order to evaluate their eutrophication status and possible nutrient limitation factors, and to investigate the main factors/sources that affect the water quality of these systems. METHODS: An extensive survey was carried out during the period from 1998-1999. Water samples were collected on a monthly basis from lakes Koronia, Volvi, Doirani, Mikri Prespa and Megali Prespa located in N. Greece. Water quality parameters (temperature, dissolved oxygen, pH and conductivity), organic indices (COD, BOD5), and N- and P-species (NO3(-), NO2(-), NH4(+), and PO4(3-), Kieldahl nitrogen and acid-hydrolysable phosphorus) were determined according to standard methods for surface water. Statistical treatment of the data was employed. RESULTS AND CONCLUSIONS: The physicochemical parameters determined in the lakes studied revealed a high temporal variation. The trophic state of the lakes ranged from meso- to hypertrophic. The nutrient limiting factor varied among lakes suggesting either P-limitation conditions or mixed conditions changing from P- to N-limitation throughout the year. Urban/industrial activities and agricultural runoff are the major factors affecting all lakes, although with a varying contribution. RECOMMENDATION AND OUTLOOK: This lake-specific research offers valuable information about water quality and nutrient dynamics in lakes of significant ecological value located in N. Greece that can be useful for an effective pollution control/management of these systems. Due to the large intra-annual variability of certain physicochemical parameters, a properly designed monitoring program of lake water is recommended.     

Sediment accumulation of organic halogens in pristine forest lakes

Sediment accumulation of organic halogen was studied in two forest lakes, one pristine and one which received 30 m³ of biologically purified bleaching wastewater from a kraft pulp mill in 1979 equivalent to ca. 2 kg of adsorbable organic halogen (AOX). Lake sediments were dated with²¹⁰Pb,¹³⁴Cs and¹³⁷Cs and the annual deposition rates of organic halogens and organic matter were calculated. Organic bound halogen contents of the sediment aged 150 years was 180 μg Cl g^?1 d.w. in both lakes. The concentration of organic bound halogen at the topmost 6 cm of the sediments (less than 20-years-old) ranged from 45 to 80 μg Cl g^?1 d.w. This suggests that solvent extractable halogen had enriched in the older sediment layers. The deposition of extractable organic halogen (EOX) in the lakes in 1950’s was 4 to 5 mg Cl m^?2 a^?1. Since then, the depositon of EOX doubled in both lakes. The deposition of organic matter increased concomitantly from 50 g m^?2 a^?1 to 110 g m^?2 a^?1 in Lake Mustalampi and from 35 g m^?2 a^?1 to 62 g m^?2 a^?1 in Lake Pyylampi suggesting that the increase in the deposition of organic halogen followed the increase in the deposition of organic matter. Of the 2 kg of organic halogen discharged into the lake, 5% or less was detected in the sediment in tetrahydrofuran extractable form 15 years later.     

Charge density of total organic carbon in Finnish lakes

Ion balance calculations were used to estimate the charge density of total organic carbon (TOC) and for calibrating the model of Oliver et al. (1983) for Finnish lakes. The database consisted of samples collected in the autumn of 1987 from 955 randomly selected lakes covering the whole country. Organic anion concentrations were estimated as the difference between Sigma cations and Sigma inorganic anions. The charge density of TOC was estimated by dividing the organic anion concentration by TOC. The median charge density was 7.5 microeq (mg TOC)(-1). In lakes with pH values lower than 4.5 the average charge density was 5.2 microeq (mg TOC)(-1) and it increased to 10.3 microeq (mg TOC)(-1) in lakes with pH higher than or equal to 7.0. The calibrated model explained 79% of the observed variability in organic anion concentration. The value for the total amount of acidic functional groups per mol organic carbon in the model of Oliver et al. (1983) was slightly higher compared to the Finnish calibration. At pH values higher than 4.4 the Finnish calibration gives lower organic anion concentrations compared to the model of Oliver et al. (1983).     

Factors affecting trace-metal bioaccumulation in Finnish headwater lakes

Fourteen unpolluted Finnish headwater lakes with pH values varying from 4.8 to 7.0 were studied for trace-metal concentrations in water, sediment, aquatic plants (Nuphar luteum L., Sparganium sp.), aquatic insect larvae (Limnophilus sp., Phryganea sp.) and fish (Esox lucius L., Perca fluviatilis L., Coregonus sp., Salvelinus fontinalis L., Salmo trutta L.). Trace-metal deposition was estimated by analysing the snowpack. Non-parametric correlation analysis was carried out between trace metal concentrations in biota and pH, ANC, TOC, CA + Mg concentration in water and a given metal concentration in water and sediment. Bioaccumulation of several trace metals increased with increasing acidity and decreasing ANC in water. This was especially true for Pb and Cd. Aquatic plants were, in general, the best indicator group concerning differences in trace-metal bioaccumulation in lakes with different acidity. There was some evidence that a higher concentration of TOC in water may reduce bioaccumulation of Pb, Cd and Zn in aquatic plants and fish. The copper concentration in sediment was the only background variable explaining Cu concentration in aquatic insects. Multivariate analysis of the whole background data gave comparable preliminary results. Over 80% of the trace metal concentrations in biota of different lakes was explained by the background variables. In general, elevated concentrations of most of these trace metals can be expected to occur in the biota of acidified low calcareous lakes.     

Morphometry and hydrology of the four large lakes of Sweden

The four largest Swedish lakes V?nern, V?ttern, M?laren and Hj?lmaren all have a tectonic origin with multidirectional fault fissures, which influence the topography of the bottoms and the creation of subbasins. All the four lakes have been subject to several glacials, the latest of which started to recede from central Sweden c. 10,000 years ago. The many differences between the four lakes can be explained by their shapes, sizes and the relation between the sizes of the drainage basins and the size of the lakes. This paper focuses on processes considered relevant to aquatic organisms of the lakes: water balance, water residence time, water temperature, water exchange between subbasins within the lakes, and other internal water movements. Links between pollution, water exchange and retention of nutrients are discussed with an example from Lake V?nern.