2008～2013年太湖蓝藻遥感监测成果分析

为了研究太湖蓝藻爆发的发生规律和演变趋势,根据2008~2013年太湖蓝藻MODIS遥感监测成果,分析了太湖蓝藻爆发与同期气象、水质和人类活动等相关因素之间的关系。分析结果表明:1近6 a来太湖蓝藻暴发总体呈现下降的趋势,蓝藻水华主要集中在太湖的西部和北部;2太湖蓝藻年度暴发总面积与年降水量和年日照时数相关性显著,降水增加和光照减少可能是促使蓝藻水华减弱的气象因素;3蓝藻的暴发通常伴随着水质的恶化,近几年太湖水质不断改善的事实说明遥感监测得到同期蓝藻水华减弱的趋势是可信的;4通过蓝藻打捞、生态清淤、引江济太调水工程等措施,对蓝藻水华的发生起到了一定的抑制作用。分析结论对于今后太湖蓝藻的进一步治理和太湖环境的保护具有重要的参考价值。     

人工湖水体富营养化的活性炭处理技术及生态修复建议

通过对包头市两个典型人工湖的水体富营养化现状分析,研究木质和煤基活性炭对人工湖中叶绿素a、COD、浊度、蓝藻、总氮和总磷的去除效果。结果表明:木质活性炭对劳动园人工湖中叶绿素a、COD和浊度的去除率更高(96%);煤基活性炭对总氮和蓝藻的去除率更高(88%),出水达到地表水环境质量标准(GB3838-2002)二级标准。同时,提出了长期治理人工湖水体富营养化的生态修复方案,以期为长期有效治理人工湖水体富营养化提供帮助。     

太湖湖泛预警监测系统及治理技术探析

目前,太湖蓝藻水华特别是太湖湖泛已成为全社会广为关注的一个热点水环境问题。研究表明,蓝藻爆发是一个缓慢的过程,通过采用恰当的预警监测技术,并开展行之有效的防范治理,可对蓝藻水华现象进行控制,甚至消除。本文主要介绍了蓝藻水华预警监测技术,并结合太湖实际情况建立了一个太湖湖泛预警监测系统,并提出了相应的蓝藻水华治理方法。     

太湖蓝藻监测及暴发情况分析

为了及时掌握太湖蓝藻发生和暴发状况,为保障流域供水安全和太湖富营养化治理提供必要的基础信息,以1996-2008年太湖各湖区藻类监测资料为基础,结合蓝藻历史变化状况,对太湖13 a的藻类群落组成、优势种的构成、数量和季节变化,以及蓝藻暴发情况进行分析,并对太湖9个湖区分区进行蓝藻暴发特征分析,探讨治理蓝藻水华的措施.结...     

太湖水富营养化蓝藻水华监测及控制研究

大多数蓝藻在较高温度下表现出最佳的生长速率,伴随着全球气温升高,我国很多地区的水资源遭受富营养化和有毒蓝藻暴发.文章以太湖为研究对象,以综合监测预报系统为基础,在预警的基础上提出了一系列应急措施.利用该综合监测系统,发现了可检测到的最大和平均蓝藻水华面积,说明蓝藻水华持续存在,没有明显缓解.研究表明,蓝藻水华发生在强烈风暴之后,这与蓝藻菌落浮力的增加有关.虽然蓝藻水华在监测期间持续存在,但蓝藻水华引起的黑水团聚的频率和强度有所降低,并没有进一步的饮用水危机.     

镇海水库蓝藻水华的影响因子分析

镇海水库为广东省开平市重要的饮用水源地。近年来大规模速生桉种植、围库养殖以及生活用水污染造成了水库水体的富营养化。2012年2月-2013年5月对镇海水库进行水质监测,通过对监测数据进行分析,发现该水库浮游植物生长基本不受N、P营养盐限制,具备蓝藻水华发生的营养盐基础。对蓝藻水华影响因子分析表明,5月-8月这段时期,水库温度为300℃-32℃,适合蓝藻水华的发生,水温与叶绿素a的浓度具有相关性,较高的水温是蓝藻发生的重要条件之一;且该时期pH值持续保持在8.36-9.99的高水平,较高的pH值也是促成蓝藻水华的重要因素。镇海水库具备引起蓝藻爆发的外在条件。     

碧山水库藻类群落特征与蓝藻水华风险分析

为掌握碧山水库藻类群落特征及蓝藻水华情况,在碧山水库设置5个点位开展丰水期和枯水期藻类现场调查。结果表明：碧山水库共鉴定出藻类7门44属63种,丰水期藻类及蓝藻丰度、生物量均显著高于枯水期,丰水期多样性指数低于枯水期;丰水期全库发生蓝藻水华,主要水华蓝藻种类是长孢藻和挪氏微囊藻。在水库管理中要注意防范水库蓝藻水华风险,建立蓝藻毒素和异味物质的监测与预警措施,保障饮用水安全。     

天津海河干流蓝藻水华暴发及防治对策探讨

对2012—2014年天津海河干流蓝藻暴发过程及成因、治理措施进行了分析,提出采取生态治理常态化、开展污染防治、科学取排水调度、生态补水常态化以及使用抑制蓝藻药剂等措施,可以有效防治海河干流蓝藻水华暴发.     

富营养化蓝藻水华发生的主要成因与机制研究综述

蓝藻是藻类中最原始的单细胞生物,也是诱发蓝藻水华的最主要藻种,文章基于国内外研究现状,对引发蓝藻水华的六类环境因素(温度、光照、水体pH与透明度、氮磷限制、生物、气候与水文)分别进行了分析。研究表明水温、氮磷和浮游动物为藻类爆发的控制因子,光照和水体pH值对浮游植物生长影响显著,透明度对不同藻类影响不同,气候与水文在一定程度上对藻类生产也有影响,同时蓝藻水华的形成机制复杂,成因多变,不同因素间的相互作用均有可能导致湖泊发生蓝藻水华。     

南方山区饮用水源水库蓝藻爆发的成因机制研究

南方山区饮用水源水库蓝藻水华成为影响当地居民生活的重要问题之一。现以我国南方江西省寻乌县九曲湾水库为例,在水库水质及纳污现状、水库水生态环境现状调查与评价、水生态系统健康状况评估的基础上,对山区饮用水源水库蓝藻暴发的成因与机制进行研究,系统总结和分析其蓝藻爆发的成因机制,以期为今后的治理提供必要的依据。     

Application of flow cytometry for examining phytoplankton succession in two eutrophic lakes

Flow cytometry has potential as a rapid assessment technique to evaluate phytoplankton biomass and species composition. It facilitates for multi-parameter analysis of individual cells on the basis of light scattering effects induced from cellular constituents, as well as auto-fluorescence. Fluorescence emission characteristics may be especially useful in classifying cyanobacteria as they contain phycoerythrin which emits light predominantly in the 550-600 nm waveband, chlorophyll-a (650-700 nm emission) and allophycocyanin (660 nm emission). The objective of our study was to assess the utility of flow cytometry for the rapid identification and sorting of freshwater algae and cyanobacteria species. Using a selection of laboratory-cultured freshwater algae and cyanobacteria species, this study demonstrated unique light scatter and fluorescent characteristics for each species examined, allowing for rapid species identification and sorting of mixed populations of laboratory cultures and samples from two lakes in the Rotorua region (New Zealand). Analysis of lake water samples collected over seven months demonstrated changes in abundance and community composition of phytoplankton in the two lakes and demonstrates that flow cytometry may be a useful technique for examining seasonal changes in phytoplankton composition.     

Seasonal variation in trophic structure and restoration effects in a deep perialpine lake (Lake Lugano,Switzerland and Italy)

Using monitoring data from the South Basin of Lake Lugano (Switzerland and Italy), we examined seasonal responses of phytoplankton and herbivorous zooplankton biomass to nearly three decades (1989–2017) of phosphorus (P) management to ask: [1] what is the trophic structure of the lake, [2] whether trophic structure and the effects of nutrient management varied seasonally, and [3] what are the implications of the existent trophic structure for the restoration of the lake. Trophic structure varied seasonally, including a structure consistent with strong consumer control (exploitation food chain) in spring and fall, and an unexpected structure in summer, characterized by a negative correlation between phytoplankton biomass and phosphorus. This structure was explained by accumulation of inedible phytoplankton (mainly cyanobacteria) at low P concentrations. Owing to a lack of apparent resource (P) control, P-management had no detectable effects on phytoplankton biomass. The trophic structures identified in the lake provides explanations for this lack of response to P-management and for the differences between the responses of the South Basin of Lake Lugano and other perialpine lakes. Based on the results, lake restoration practice would benefit from a greater understanding and an increased ability to predict trophic structure within and across lakes.     

三维水质模型在城市人工湖设计中的应用

基于人工湖设计的灵活性和后期的可调控性,运用三维水质模型,对人工湖设计方案进行水动力和水质富营养化的预测研究,通过定量计算得到最适的人工湖设计方案。以镇江金山人工湖为实例,对湖形设计、水调控措施等设计方案对水质的影响进行计算模拟,在此基础上完善人工湖设计并制定长效管理措施,建议在不易暴发富营养化的时间段先行引长江水以降低初始营养盐浓度,从而控制叶绿素a浓度的增长。     

浅水湖泊水生态数学模型研究及应用

该文针对珠三角感潮浅水湖泊水环境模拟问题,在二维水流-污染物输移耦合数学模型基础上,结合WASP(water quality analysis simulation program)水生态数学模型原理,考虑溶解氧、氨氮、硝酸盐氮、有机氮、无机磷、有机磷、碳生化需氧量和叶绿素a等8个水质变量及其相互作用的溶解氧平衡子系统、氮循环子系统、磷循环子系统和浮游植物动力学子系统,建立了浅水湖泊水生态数学模型。通过室内实验系统模拟了珠三角某典型感潮人工湖泊外江来水营养条件对蓝藻生长的影响,确定了蓝藻生长速率等关键模型参数,并模拟了湖泊不同换水方案下叶绿素a的时空分布规律,为控制湖泊水体富营养化、预防蓝藻水华爆发提供科学依据。     

Statistical Changes of Lake Stages in Two Rapidly Urbanizing Watersheds

Understanding changes induced by watershed urbanization is integral to developing an effective long-term management strategy. In this research, the authors study statistical changes of lake water surface levels in two urbanizing watersheds by evaluating serial change in time series parameters, autocorrelation, and variance as well as by developing a regression model to estimate weekly lake level fluctuations. The authors fit a seasonal integrated autoregressive moving average model to lake levels over subperiods of the data record to identify trends in parameter values. The authors fit the regression model with rainfall, lake stage, and temperature components for pre-urbanized and urbanized time periods to identify changes in baseflow. The lakes were located in Pasco County, Florida, USA and have not been significantly influenced by changes in rainfall patterns, pumping, surface water extraction or physical modification. Furthermore, the lakes exhibit consistent watershed urbanization and have sufficiently long and complete records. Based upon the research, the authors reach the following general conclusions about lakes in urbanizing watersheds: (1) the statistical structure of lake level time series is systematically altered, (2) in the absence of other forcing mechanisms, autocorrelation and baseflow decrease, (3) the presence of wetlands adjacent to lakes can offset the reduction in baseflow. These conclusions can be applied globally to similar regions that consist of lakes undergoing urbanization in flat, humid, shallow water table environments with wetlands. Furthermore, the methodology utilized can be applied at lakes in both similar and dissimilar environments to those studied in this research.     

云南典型高原湖泊富营养化及其生态修复研究

始于70年代末80年代初的湖泊富营养化问题,严重阻碍了云南社会经济发展,继而引起了人们极大地关注。已有的研究从富营养化特征、机制、演化以及生态、工程修复等方面进行了相关探究,其1980—2010年湖泊水体总磷、总氮、透明度、叶绿素、生化需氧量及营养状况指数等均指示和记录了近30年来云南典型高原湖泊富营养化特征及演化过程。在系统总结前人研究成果的基础上、基于云南高原湖泊富营养化的典型性与差异性、富营养化演化及其修复现状的背景下认为:近年来富营养化水体水质好转大多只是季节性或区域性迹象,云南高原湖泊整体上乃处于持续的富营养化和污染状态,部分湖泊因为周边农业用地和建设的扩展已经导致湖泊处于不可恢复状态,抚仙湖、阳宗海等湖泊周边因开发需水量大,导致湖泊水位出现快速下降和湖容大量减少。进一步对云南高原典型富营养化湖泊开展更大时间尺度的研究,特别是湖泊变化机理的研究和趋势预警的升级是今后努力的重点和方向。     

邵伯湖水生态状况及改善建议

过水型湖泊在承担防洪、保障人民生命财产安全的基本任务前提下,在用水、航运、旅游及维系区域生态平衡方面也发挥着巨大作用,通过对常规水质指标以及微生物指标的研究,探索过水型湖泊富营养化的微生物评价方法,针对湖泊水生态更替规律开展基础性研究,提升湖泊水生态管理水平。     

Application of artificial neural networks for classifying lake eutrophication status

Several artificial neural network architectures were ‘trained’ on data from the Eastern Lake Survey – Phase I of the Environmental Protection Agency's National Surface Water Survey in order to investigate which physical–chemical parameters are possibly of greatest importance in determining the eutrophication status of lakes. From the 110 available lake parameters in the Survey, 60 were chosen as input to the neural networks. The traditional eutrophication classification scheme of Vollenweider was used for comparative purposes. The various artificial neural network simulations showed that, in addition to total phosphorus and inorganic nitrogen, turbidity, specific conductance, lake elevation and hydrogen ion concentration were identified as the most significant parameters affecting the classification of lakes in regard to their eutrophication status. These results suggest a conceivable association between these parameters and lake eutrophication, thereby indicating a need for further study on these relationships. A model simulation utilizing an unsupervised neural network did not provide much insight into the lake eutrophication status, but did show that the available physical–chemical lake data could be categorized according to physical region, thereby providing an indication that the lake data used in this study were region‐dependent.     

青藏高原湖泊分布特征及与全国湖泊比较

我国青藏高原分布着地球上海拔最高、数量最多、面积最大,以盐湖和咸水湖集中为特色的高原湖群区,形成与长江中下游平原稠密淡水湖群区遥相呼应之势。据统计,仅西藏和青海两省(区)面积大于1 0km2的湖泊就有1091个,约占全国湖泊总面积的49 4%。其中,面积大于10 0km2的湖泊有346个,占两省(区)湖泊总面积的95 2%。在区域气温不断升高、冰川融解退缩的情况下,通江和依赖冰川补给的湖泊扩张淡化。另一方面,众多的降水径流补给的湖泊退缩、咸化及至消亡。青藏高原环境变化趋势,既是响应全球气候变化的结果,又是其通过自身调整寻求新的动态平衡的反映。     

Seasonal dynamics of physico-chemical characteristics and biological responses of Lake Chilwa,Southern Africa

Lake Chilwa is shared by Malawi and Mozambique, it supports an important fishery and its watershed is undergoing rapid population growth and increasing utilization for agricultural production. It is a shallow, closed basin lake with extensive surrounding wetlands; and it has suffered several desiccation events in the last century. To better understand the current condition of the lake, we monitored a suite of physical, chemical and biological parameters at approximately monthly intervals over an annual cycle in 2004–2005. The limnology of the lake was extremely sensitive to seasonal changes in the lake's seasonal hydrological cycle. The physico-chemical parameters, temperature, electrical conductivity, and total suspended solids exhibited clear seasonal patterns driven by the highly seasonal rainfall and resultant lake levels. In response, phytoplankton and zooplankton abundance, as well as biologically dependent oxygen concentrations and pH, exhibited several maxima levels over the year. The peaks of phytoplankton and zooplankton were out of phase suggesting a lag in the zooplankton grazing in response to pulses in primary productivity. Chlorophyll concentrations can exceed 1 mg/L in surface waters indicative of hypereutrophic conditions, but they fell dramatically during zooplankton peaks. This hydrologically driven, shallow and mesohaline lake is a productive and critical resource to the region. Its management poses challenges arising from the dependence of its limnology and fishery on the lakes hydrology, catchment land use and climate variability.