土壤重金属生物毒性研究进展

世界范围内土壤重金属污染不断加重,由污染所带来的问题以及如何治理污染已经受到人们越来越多的关注.土壤重金属将对土壤生物产生影响,而土壤生物在重金属的胁迫下也会产生不同的响应.综述了国内外近年来土壤重金属生物毒性的研究进展,介绍了土壤重金属污染对陆地生态系统中植物、动物和微生物生长的影响;土壤重金属生物毒性的影响因素;土壤重金属生物毒性的研究方法;土壤重金属生物毒性的预测模型,最后提出了问题和展望.     

中国东北地区非点源污染研究进展

为掌握东北地区非点源污染研究动态和明确研究中存在的问题和不足,对近20年（1991-2008年）东北地区有关非点源污染研究成果进行检索、分类和统计分析,以便更好地进行区域水环境治理和污染防治.东北地区非点源污染研究总体呈增加趋势;研究内容包括水环境污染源调查分析与评价、污染负荷量化、机理探索、模型模拟和污染防治5类;研究对象包括氮、磷、泥沙、农药和重金属;经验方法估算污染负荷较多,机理模型应用成功实例较少;研究性论文中以农业非点源污染较多,城市非点源污染较少;治理措施停留在水土保持措施层面上,缺乏对水土保持措施的优选评价和对最佳管理措施的评价研究.目前,东北地区非点源污染研究处在理论探索阶段,非点源污染是否是主要污染源还存在争议.今后应着力于措施应用、评价和基础数据收集及区域非点源污染物的确定和污染负荷的量化研究;尝试新技术和多领域交叉合作,为区域水环境治理提供科学依据.     

农业非点源污染模拟不确定性研究进展

随着点源污染控制水平的提高,非点源污染问题日益突出.农业非点源污染由于具有涉及范围广、控制难度大、模拟过程不确定因素多等特点,已成为当前水环境污染防治研究的热点与难点.本文围绕农业非点源污染模拟的不确定性问题,介绍了国内外常用的农业非点源污染模型及其不确定性来源,着重讨论了模型结构、参数和输入信息不确定性的研究方法及其应用进展;提出了今后的研究趋势,指出定量分析非点源污染的不确定性,获取影响非点源污染负荷的关键因子,可以有针对性地进行非点源污染的预防和管理,对于提高非点源污染研究水平和制定有效的污染防治措施均具有重要意义.     

支原体污染细胞的处理方法

<正> 在细胞培养技术中,支原体污染细胞系是一常见问题。受污染细胞的生长和代谢均受到影响,在用该细胞作免疫学试验时。就有可能产生异常结果.尤其在单克隆抗体制备中,污染支原体的骨髓瘤或杂交瘤细胞会导致融合失败或抗体分泌能力下降以至丧失。支原体污染细胞的危害之大,研究建立控制支原体污染的方法也就受到学者们的关注。     

基于增强回归树的流域非点源污染影响因子分析

地表水的非点源污染在点源污染不断得到控制的前提下已经成为水环境污染的首要问题.非点源污染影响因子的复杂性及不确定性一直是流域非点源污染研究的重点和难点.本文利用SWAT(Soil and Water Assessment Tool)模型,以辽河子流域汎河流域为例,模拟了2003—2012年的非点源污染状况,对其空间分布状况进行了分析,并应用增强回归树的方法定量分析各种影响因子(坡度、土地利用类型、高程和土壤类型)对该流域非点源污染的贡献率.结果表明: 在汎河流域,非点源污染呈现较高的空间异质性,其中总氮的空间分布差异较大,总磷的空间分布差异较小.坡度因子与载体泥沙、总氮和总磷均呈极显著正相关关系(P<0.01),对泥沙和总磷有显著影响,其贡献率分别为46.5%、38.2%;土地利用因子对载体泥沙、总磷的负荷量有重要影响,其贡献率分别达到27.2%、35.3%;高程较低、坡度较缓的耕地地区易产生较高的总磷负荷量;褐色土壤最易流失总磷,而草甸土易流失总磷,且易受泥沙侵蚀.本研究利用增强回归树模型克服了流域非点源污染影响因子的复杂性,可加深对非点源污染产生机制的理解.     

汞污染土壤植物修复中转基因技术的应用

汞是一种全球性污染物.随着工业的发展、汞矿开采的加速,土壤汞污染日益严峻,给生态环境和人类生活带来了严重的威胁.因此,汞污染土壤的修复问题受到了广大学者的关注.针对受污染的土壤修复问题,植物修复技术具有成本低和不会给环境带来新的危害等特点.本文对目前国内外汞污染土壤修复植物修复技术的研究进行了综述,介绍了转基因技术在汞污染土壤中的应用,探讨了转基因技术在环境治理和环境修复中潜在的应用价值.     

藻类等植物对水污染的监测

目的熟悉用藻类等植物监测水污染的技术和方法,用来监测水污染。器材显微镜、广口瓶、吸管、水生植物(见下)。步骤 1.选学校附近水池或河流4处:1处水严重污染;1处是中等污染;1处是轻度污染;1处     

上海世博会规划区不同土地利用方式下附属绿地的重金属分布

上海世博会规划区是工厂和居民区混杂的典型老城区.对其主要土地利用方式下附属绿地土壤的重金属进行调查分析.结果表明:部分样点的Ni、Cr、Cu、Zn、Pb和Cd含量超标,Hg和As的含量均没有超标;大部分绿地土壤没有出现重金属的污染,其中清洁安全和尚清洁占了69.83%和6.94%,轻度污染、中度污染和重度污染的分别占了12.87%、2.56%和7.81%;周边利用类型不同的附属绿地土壤重金属含量差别很大,居民办公区的绿地土壤没有出现重金属污染,试剂溶剂类工厂局部有重金属污染,重金属污染主要集中在造船厂、机械厂、钢铁厂等重型工厂的附属绿地;利用类型不同绿地土壤重金属的相关性也不同,重金属的相关性基本与产生污染的土地利用类型一致;污染源的距离以及对污染源保护不当是导致绿地土壤重金属污染的主要因素,注意对污染源的集中堆置或采取隔离措施,能有效减少重金属对绿地的污染.     

细胞培养技术简介及避免污染的策略

细胞试验是分子生物学科学研究的重要手段之一,而细胞培养技术又是细胞试验中不可或缺的关键性技术方法.简要地介绍细胞培养的过程,试剂和方法,并着重论述细胞培养中经常出现的污染问题,造成污染的原因,分辨污染的方法.通过从实际工作中总结出来的经验,从环境、试剂和操作诸方面对避免污染的方法进行了讨论.     

菜地土壤氮磷面源污染现状、机制及控制技术

为了提高蔬菜产量,菜农大量施用化肥,菜地氮磷肥用量在一些地区已超过蔬菜实际需求量的数倍;而大多数蔬菜是浅根系和没有庞大根系的作物,菜地土壤已出现明显的氮磷累积现象,从而导致蔬菜作物营养失调,硝酸盐含量严重超标、品质下降,并引起菜地土壤理化性状恶化、地下水硝酸盐污染及地表水富营养化等一系列环境问题.本文综述了菜地土壤氮磷面源污染现状(氮磷累积特征、对水环境及蔬菜污染现状)、污染机制(氮磷来源、转化特征及损失途径)及包括施肥控制技术、应用化学添加剂技术、填闲作物技术、种植制度优化技术、汇源景观组合和生态草带拦截技术等污染控制技术,旨在为菜地土壤氮磷面源污染的深入研究提供借鉴.     

Phytoplankton periodicity in Ogelube Lake,Anambra State,Nigeria during 1979–1980

Ogelube is a tropical oligotrophic lake having a desmid dominated phytoplankton with maximum density during the warmest season. During the rainy season, the lake cools, phytoplankton declines and dominance shifts to algae other than desmids. The lake cools further as harmattan advances, while phytoplankton reaches its minimum, suggesting water temperature to be more important than other environmental conditions. Decrease in phytoplankton density with falling water temperature was probably due to slower reproduction, rather than to increased death rate.     

Residents’ concerns about lake uses and environments: a comparative study of Lakes Kasumigaura,Suwa, and Biwa in Japan

Lakes are a common water resource. This study analyzed residents’ concerns regarding their lake environments to help solve lake environmental problems. The study area comprised three lakes in Japan—Kasumigaura, Suwa, and Biwa—which have different tendencies to change in water quality. A sample of 1200 respondents was evenly distributed among the three lake regions. A questionnaire survey asked about respondents’ proximity to the lake, their concerns about the lakes’ uses and environments, their evaluations of the lakes, and their opinions regarding environmental improvements. The number of options chosen in response to the multiple-answer questions was used to measure the extent of concern. The results found that knowledge of the water environment, general environmental concerns, the amount of travel time to the lake, and the visiting interval were significantly related to concerns about the lake environment. The results of logistic regression analysis found that high environmental concerns positively influenced attitudes toward lake use. Ways to increase concerns for lake environmental problems and the relationship between concerns and attitudes toward solving lake environmental problems are discussed.     

河湖生态系统生态用水优化研究——以滇池流域为例

生态需水是河流与湖泊生态系统健康的重要基础。湖泊流域的河流与湖泊生态系统之间存在密切的水量联系,目前对流域内生态用水的研究多为单一生态系统生态需水简单相加,忽略了河流和湖泊之间复杂的水量联系。基于河湖复合生态系统之间的水量联系构建了河湖生态系统生态用水优化模型,并以滇池为例分析了河湖生态系统生态用水规律。结果表明：湖泊流域中单一河流或湖泊生态需水计算结果不能满足复合生态系统的生态用水要求,需要综合考虑河流和湖泊之间的水量联系;在当前水质状况下,牛栏江每年的调水量不能满足滇池流域的生态用水要求;滇池流域水体污染对流域内生态用水影响较大,随着水体污染程度的下降,流域生态用水量和调水量呈指数下降,河流生态用水呈线性下降。     

洱海低污染水处理湿地中应用海菜花的可行性

人工湿地因其成本低、效率高、地区适宜性强等特点,成为洱海低污染水处理的优先考虑手段之一。人工湿地的建设及运行不仅仅是技术问题,而是要充分考虑当地的实际,挖掘其资源（植物产品）价值。从技术、环境、生态以及经济角度论证了将乡土经济植物海菜花应用于湿地系统中的可行性,结果表明：1）海菜花人工种植技术较为成熟,能为洱海低污染水处理湿地中海菜花的存活和丰产提供保障;2）洱海气候适宜应用湿地系统,低污染水营养足以保证海菜花生长。而海菜花四季生长旺盛,具有一定的净水能力。就环境可行性来讲,海菜花完全可以应用到洱海低污染水湿地净水系统中去;3）将海菜花应用到洱海低污染水湿地净水系统中,有助于增加洱海的生态景观效益,不仅可以规避外来物种入侵风险,而且有利于濒危物种的恢复,生态可行性较好;4）将海菜花应用到湿地净水系统中,可以充分利用来水中营养盐,变废为宝,同时持续稳定地产生较好地经济效益,为因湿地建设而失地的农民提供生活保障。     

Effects of the discharge of thermal effluent from a power station on Lake Wabamun,Alberta, Canada — Limnological features

The physical and chemical aspects of Lake Wabamum have been described. Modifications to the thermal and dissolved oxygen regimes through the discharge of thermal effluent into the eastern region of the lake are discussed. This discharge has, therefore, changed the environmental conditions under which the biota exists in the eastern portion of the lake. It was also shown that this discharge of heated water had no effect upon the water chemistry while the power station itself contributed silica, in the form of fly ash, to the system. Tables of the phytoplankton, zooplankton, aquatic macrophytes, and fish are provided. From a biological and limnological stand point the lake can be classified as a moderately eutrophic lake, especially in the eastern portion.     

艾比湖流域生态环境演变与人类活动关系初探

艾比湖流域生态环境演变与人类活动关系初探杨云良阎顺贾宝全陈利军（中国科学院新疆地理研究所,乌鲁木齐８３００１１）ＡＰｒｅｌｉｍｉｎａｒｙＳｔｕｄｙｏｎｔｈｅＲｅｌａｔｉｏｎｓｈｉｐＢｅｔｗｅｅｎｔｈｅＥｎｖｉｒｏｎｍｅｎｔａｌＥｖｏｌｕｔｉｏｎａｎｄ...     

生态输水前后台特玛湖生态环境变化探究分析

自上世纪 60 年代以来, 由于塔里木河上中游水资源的不合理开发利用, 导致河流下游及台特玛湖干涸, 干涸的湖底荒漠化快速发展。生态输水后, 湖泊面积恢复并扩大, 生态环境改善, 荒漠化逆转。根据对研究区域多次实地考察、结合前人研究的成果资料、借助GIS(Geographic Information System)和 RS(Remote Sensing)技术对1990-2018年台特玛湖湖区水域面积变化及其对生态环境的影响进行了分析。结果表明: 生态输水后台特玛湖水域面积明显扩大, 生态环境明显改善。深入分析引起台特玛湖区域生态环境变化的原因并进行敏感性评价, 最终提出科学合理的台特玛湖区域生态环境综合治理方案, 为塔里木河下游环境保护管理决策提供科学依据和技术支撑。     

Development of a visualization platform oriented to Lake water quality targets management - A case study of Lake Taihu

Lake Taihu is well known for its severe environmental degradation. In previous studies of lake quality target management, the water quality targets were poorly correlated with watershed pollutant reduction, and most studies lacked visualized management platform that covered all elements including lakes, in-lake estuaries, rivers and watershed regions. In this study, a browser/server-based visualization platform for lake quality target management was developed. Five models that covered both the watershed and lake scales were integrated based on two critical functions. First, the proposed method can be used to determine watershed pollutant reduction amounts based on certain lake quality target parameters, such as those for TN, TP, NH₃N and COD. Second, the method can simulate the lake quality trends associated with different watershed adjustment plans. The platform was deployed by the Taihu Basin Authority (TBA) of the Ministry of Water Resources. Overall, this platform is a useful tool for watershed-lake environmental management.     

Role of atelomixis in replacement of phytoplankton assemblages in Dom Helvécio Lake, South-East Brazil

Scale and frequency of changes in a lake’s physical structure, light dynamics, and availability of nutrients are closely related to phytoplankton ecology. Since phytoplankton assemblages were first described, phytoplankton ecologists concluded that these assemblages provide insight into phytoplankton responses to environmental changes. Objectives of this study were to investigate ecology of phytoplankton during a complete hydrological cycle in the deepest natural lake in Brazil, Dom Helvécio, and to sort species into the list of assemblages, checking its accordance with environmental changes in a tropical system within the middle Rio Doce Lake district, South-East Brazil. Canonical Correspondence Analysis, t-test, Mann–Whitney U-test, and Kruskal–Wallis test were used to analyze climatological, environmental, and plankton data, which were obtained monthly in 2002. A new phytoplankton assemblage, N_A (atelomixis-dependent desmids), is suggested because atelomixis (robust movement of water occurring once a day) contributed to replacement of species in Dom Helvécio Lake. Stability of stratification, water chemistry, and composition of phytoplankton assemblages characterized two periods. The first period occurred in six rainy months (Jan–Mar and Oct–Dec) when the lake was stratified and phytoplankton was dominated by two assemblages: N_A and F. The second period occurred in six dry months (Apr–Sep) when the lake was nonstratified and phytoplankton was dominated by four assemblages: S2, X1, A, and L_O. Results suggest that phytoplankton in Dom Helvécio Lake was shaped by seasonal and daily changes of water temperature, even with its lower amplitude of variation within 2002 (El Niño year). These changes promoted water column stratification or mixing, reduced light, and increased nutrient availability. Temperature, therefore, is similarly important to phytoplankton ecology in tropical regions as it is in temperate ones. Sorting phytoplankton species into assemblages matched well with environmental changes and periods identified so it is also suggested that this can be further used as an appropriate tool to manage water quality when evaluating tropical lakes.     

Impacts of space,local environment and habitat connectivity on macrophyte communities in conservation lakes

Aim  To assess the relative impacts of spatial, local environmental and habitat connectivity on the structure of aquatic macrophyte communities in lakes designated for their conservation value. Location  Selected lakes of conservation importance all over Scotland, representing a wide variety of lake habitat types and associated macrophyte communities. Methods  Local environmental variables and species occurrence were measured in the field. Spatial variables were generated using principal coordinates of neighbour matrices (PCNM) analysis. Connectivity between each lake and its neighbours was defined as either (i) all lakes within a radius of 5, 10, 25, 50, 75 or 100 km; (ii) all lakes in same river system; or (iii) all lakes in the same catchment and upstream of the lake. Using variance partitioning within canonical correspondence analysis, the relative impact of E = local environment, S = space and C = lake connectivity was compared on submerged (n = 119 lakes) and emergent (n = 96 lakes) macrophyte assemblages. Results  Local environmental conditions, such as total phosphorus, alkalinity/conductivity and the presence of invasive species, as well as spatial gradients were key drivers of observed variation in macrophyte communities; e.g., for submerged macrophytes, a combination of local to moderate factors relating to water chemistry and broad‐scale gradients reflecting elevation and climate are important. Spatially structured environmental variables explained a large portion of observed variation. Main conclusions  Our findings confirmed the need to manage local environmental pressures such as eutrophication, but suggested that the traditional catchment approach was insufficient. The spatial aggregation of environmental and connectivity factors indicated that a landscape scale approach should be used in lake management to augment the risk assessment to conservation species from the deterioration of suitable lake sites over broad biogeographic areas.