黑龙滩水库水体生态系统酶活力及其生态学意义研究

本文黑龙滩水库水体生态系统中脲酶与磷酸酶活力及其与多种水质参数之间的关系进行了研究，结果表明：（１）酶活力与水质，水温变化呈出现一致的动态变化规律。（２）黑龙滩水库水体中脲酶来源与水生生物关系不大，而磷酸酶主要来自浮游植物和水生细菌。（３）水体中脲酶活力受水中总氮浓度瓣影响，而磷酸酶活力不受水中磷酸盐的抑制。     

利用栗褐芽孢杆菌除藻的试验研究

应用筛选出的溶藻细菌--栗褐芽孢杆菌(Bacillus badius)进行除藻试验,结果表明该溶藻菌种除藻效果显著,对藻类的去除率在70%以上,对氨氮和有机物也有较好的去除效果;栗褐芽孢杆菌通过其分泌的一种特殊物质灭活藻类.     

内源磷的释放作用及影响因素研究进展

水体的富营养化已成为目前环境研究中的焦点问题,磷在湖泊中的浓度高低是衡量湖泊富营养化水平的重要指标,是水生态系统基本营养盐之一,并且是淡水湖泊的最主要限制性营养因子。在外源磷得到有效的控制之后,内源磷的污染仍然能够保持湖泊的富营养化状态,此时内源磷的控制就成为了难点和重点。在底泥中的结合态磷,主要是以无机磷和有机磷的形式存在,有机磷与微生物活性密切相关,无机磷则主要与底泥存在的环境联系紧密。湖泊底泥内源磷释放受到一系列物理、化学、生物过程的控制,其影响因素主要包括扰动、氧化还原电位、pH值等,是多种因子综合作用的结果,同时,扰动引起的底泥再悬浮对内源磷有吸附固定作用。故底泥内源磷的释放机理有待进一步探索,在多种影响因素作用下,进一步研究底泥再悬浮对磷的吸附释放作用,从而明确内源磷的主要来源及吸附释放过程,为内源磷的控制提供理论依据,进而控制水体富营养化。     

阳澄湖氮磷时空变化特征及富营养化评价

基于2015年～2017年的监测数据,分析了氮磷在阳澄湖内的空间分布以及时间变化规律,并采用综合营养状态指数法(TLI)评价了阳澄湖水体的富营养化状态。研究结果表明:①2015～2017年,阳澄湖TN浓度波动不大,但是TP浓度持续升高,特别是中湖和东湖,分别升高了81.7%和113.8%;除2017年外,TN、TP浓度均是西湖最高,东湖最低,2017年中湖TP浓度升至最高;阳澄西、中、东湖每年的TN/TP比较接近,且都逐年下降。②年内变化来看,TN浓度每年1～3月较高,7～9月较低,而TP浓度无明显季节变化规律;TN/TP每年1～4月较高,一般在30以上,每年5～10月较低,一般在7～30之间。③TLI值显示阳澄西湖的富营养化状态有所好转,而中湖、东湖的富营养化状态呈恶化趋势。三年中,西湖、中湖均处于轻度富营养状态,东湖2015年为中营养,2016和2017年转变为轻度富营养。     

环境中的污染物

<正>由于人类的活动所产生的环境污染物,一般可分为化学性、物理性与生物性三大类。化学性污染物主要有无机物(汞、镉、砷、铬、铅、氰化物、氟化物等)、有机物(有机磷、有机氯、多氯联苯、酚、多环芳烃等);物理性污染物主要有噪声、振动、放射性、非电离电磁波、热污染等;生物性污染物主要有细菌、病毒、原虫等病原微生物。     

好氧颗粒污泥降解邻苯二甲酸二甲酯的影响因素研究

本文研究了好氧颗粒污泥系统中,温度、pH、曝气强度、邻苯二酸(Phthalic Acid,PA)及氨氮(NH3-N)对邻苯二甲酸二甲酯(Dimethyl Phthahte,DMP)降解效果的影响,结果表明:好氧颗粒污泥降解DMP的最佳温度、最佳PH值范围、最佳曝气强度分别为25℃～45℃、7.0 ～9.0、1.38 cm/s.当PA浓度为100 mg/L、300 mg/L,PA对DMP降解起促进作用;当PA浓度为500 mg/L、800 mg/L,PA对DMP降解起抑制作用.进水中50 mg/L的氨氮浓度对DMP降解的影响不大.本研究中采用的19种运行工况条件中,除曝气强度为0.33 cm/s以外,其他18种运行工况条件下,当运行时间达到300 min时,DMP的浓度都小于1.0 mg/L,因此,当水力停留时间达到5h以上时,温度、pH、PA、氨氮对DMP降解速率的影响基本上可以忽略不计.     

瀛湖水质变化特征及富营养化控制研究

瀛湖作为南水北调中线工程丹江口水库的重要水源地，水环境质量状况日益受到各方关注。对近五年(2016～2020年)瀛湖水质状况及富营养化现状进行综合评价，同时采样SPSS软件对2020年瀛湖366组日均值水质监测数据统计分析，结果表明：近五年(2016～2020年)瀛湖均处于中营养化水平；在气温回升的3月份，瀛湖pH值和溶解氧出现全年最大值，在气温最高的8、9月份水温、浊度、总磷、叶绿素和藻密度浓度为全年最高，水体电导率、总氮浓度为全年最低；总氮和藻密度呈显著负相关，总磷和藻密度呈显著正相关。分析表明磷是瀛湖藻类生长的限制性营养盐，瀛湖富营养化控制应以集中控磷为主。为瀛湖水体富营养化控制和水环境治理提供了科学依据。     

铀吸附实验研究现状

介绍了铀吸附实验的研究现状，对吸附铀的各种载体进行了总结。目前，主要采用静态法（批示法）和动态法（柱法）进行铀的吸附实验研究。吸附铀的载体主要有粘土，金属的水合氧化物等肢体，藻类及菌类，树脂等。主要考察pH值、温度、吸附时间、阴离子、阳离子、细菌浓度、铀浓度等对吸附速率及吸附量的影响。     

PPb级磷的钼兰显色、滤膜吸着、溶剂溶解的分光光度比色法

近年来对环境水和排放水中磷浓度的标准限量不断加严,特别是一类环境水质的磷最高限量定为5μg/L。对此极低浓度的定量法,多数提案在感度、精度方面,以及操作简便、快速方面不能满足要求。日本环境厅公布的μg/L级(即PPb级)磷定量法,从振荡到分层静置,萃取有机层的分离……等操作,既费时又繁复,精度也差。     

篦齿眼子菜对废水中氮和磷的去除行为研究

一些常见的沉水草本植物对水质具有较强的净化作用,能够有效控制氮和磷的浓度.本试验通过模拟氮、磷污染的水质条件,采用篦齿眼子菜对氮、磷营养盐的吸附和去除效果进行研究.结果 表明:设定模拟废水中的初始总氮(TN)浓度在1～50 mg/L范围内,培养30天后的植株对总氮的去除率最高可达85.4％,随着初始培养环境中总氮浓度的...     

Magnesium-rich minerals in sediment and suspended particulates of South Florida water bodies: implications for turbidity

Fine sediments in shallow water bodies such as Lake Okeechobee are prone to resuspension. Predominantly inorganic "mud" sediment that covers approximately 670 km2 of the lake has been recognized as a persistent source of turbidity. The objective of this study was to determine if mineral components of sediments in Lake Okeechobee and water conveyances of the northern Everglades also occur as suspended sediment and hence constitute a potential abiotic contributor to turbidity. Sediment samples were collected from nine stations within the lake and eight locations north of Water Conservation Area 2A in the Everglades. Water samples were also collected at selected locations. The silt and clay mineralogy of sediment and suspended particles was determined using X-ray diffraction, thermogravimetry, scanning-electron microscopy, energy-dispersive X-ray elemental microanalysis, and high-resolution transmission-electron microscopy. Clay fractions of the lake sediment contained the Mg silicate minerals sepiolite and palygorskite, along with smectite, dolomite, calcite, and kaolinite. Sediment silt fractions were dominated by carbonates and/or quartz, with smaller amounts of Ca phosphates and sepiolite. Mineralogy of the mud sediment was similar to that reported for geologic phosphate deposits. This suggests that the mud sediment might have accumulated by stream transport of minerals from these deposits. Suspended solids and mud-sediment mineralogy were similar, except that smectite was more abundant in suspended solids. Everglade samples also contained Mg-rich minerals. The small size, low density, and fibrous or platy nature of the prevalent mud sediment minerals make them an abiotic, hydrodynamically sensitive source of persistent turbidity in a shallow lake. Mitigation efforts focused exclusively on P-induced biogeochemical processes do not address the origin or effects of these minerals. Ecological management issues such as turbidity control, P retention, geologic P input, and suitability of dredging are related to mud-sediment properties and provenance.     

汽车用材料——PA66及其玻璃纤维复合材料在不同介质中的老化行为研究

在三种介质（二次水，汽油，乙二醇，50℃温度）条件下对PA66及PA66／GF进行95天左右的人工模拟材料在汽车使用环境下的加速试验，对不同老化时间的PA66及PA66／GF试样进行了宏观力学测试及吸湿性测试，并进一步利用示差扫描量热法（DSC），红外光谱及扫描电镜等手段分析老化前后试样的微观结构及组织差异。结合老化前后试样的力学性能变化，揭示了PA66及复合材料的老化规律和机理。实验表明，PA66及PA66／GF在三种介质中拉伸强度呈现下降趋势。其主要机理是介质溶液对试样渗入的结果影响，降低了分子间的相互作用力（范德华力）从而使材料机械性能下降；同时未发现化学作用对材料的力学性能有明显的变化。     

基于流域视角的水环境综合治理规划研究——以江苏省淀山湖为例

以流域为单元进行水资源综合规划和管理是实现水环境改善的重要途径。本文以太湖流域第二大省界湖泊—淀山湖为例,在综合分析流域水环境质量基础上,利用GIS 分析工具划分流域治理片区并制定分区管控策略。根据流域所含骨干河流流向、骨干河流与淀山湖交汇特点、上中下游不同河段及镇域行政边界,将淀山湖流域分为吴淞江流域、千灯浦- 淀山湖流域、昆南湖荡流域、元荡湖荡流域、太浦河流域五大片区138 个子评价单元。通过水环境容量与压力两类空间叠加分析,构建形成污染重点减排区、污染综合治理区、产业绿色化提升区、生态环境保育区等四个类型区域,并提出差异化的产业准入和环境治理措施。本研究不仅为以流域为治理单元的水环境治理规划提供了较为可行的技术体系,而且为太湖流域水环境综合整治思路创新提供了可借鉴的案例。     

PHOSPHATE IN WATERS: I. REDUCTION USING NORTHERN LIGNITE FLY ASH1

Fly ashes fiom lignite coal fixed steam electric plants contain appreciable amounts of materials that can, in principle, decrease the phosphorus concentration in surface waters. Typical samples of un-weathered fly ash were used to test efficacies of removal of phosphorus from standard phosphate solutions and actual lake water samples. The effects of changing parameters such as contact time, pH, fly ash/water ratios, and solution temperature are presented. Water soluble and insoluble factors in the ash both appear to be reactive constituents. Trials with municipal waste waters showed near quantitative removal of ortho-phosphate.     

Conditions affecting the release of phosphorus from surface lake sediments

Laboratory studies were conducted to determine the effect of pH and redox conditions, as well as the effect of Fe, Mn, Ca, Al, and organic matter, on the release of ortho-phosphates in lake sediments taken from Lakes Koronia and Volvi (Northern Greece). Results were evaluated in combination with experiments to determine P fractionation in the sediment. The study revealed the major effect of redox potential and pH on the release of P from lake sediments. Both lakes showed increased release rates under reductive conditions and high pH values. The fractionation experiments revealed increased mobility of the reductive P fraction as well as of the NaOH-P fraction, indicating participation of both fractions in the overall release of sediment-bound P, depending on the prevailing environmental conditions. The results were assessed in combination with the release patterns of Fe, Mn, Ca, Al, and organic matter, enabling the identification of more specific processes of P release for each lake. The basic release patterns included the redox induced reductive dissolution of P-bearing metal oxides and the competitive exchange of phosphate anions with OH- at high pH values. The formation of an oxidized surface microlayer under oxic conditions acted as a protective film, preventing further P release from the sediments of Lake Volvi, while sediments from Lake Koronia exhibited a continuous and increased tendency to release P under various physicochemical conditions, acting as a constant source of internal P loading.     

A participatory approach to ecosystem conservation: fuzzy cognitive maps and stakeholder group analysis in Uluabat Lake,Turkey

Fuzzy cognitive mapping was used to develop a participatory ecosystem management plan for Uluabat Lake, Turkey. Interviews were conducted with stakeholders belonging to six different groups. Lake pollution was the most central and most mentioned variable for stakeholders. Stakeholder groups agree that lake pollution is negatively affecting ecosystem health and thereby local economies. Thus, reducing lake pollution was chosen as the overall goal for the management plan. Possible ways to reduce lake pollution and increase ecosystem health were seen differently by the different groups. Hunters, factory managers, NGO personnel, and local people thought industry was the main cause of lake pollution, while officials from the government and local municipalities thought roads and urban development contributed the most to lake pollution. Generally the stakeholder groups did not perceive their own actions as affecting the lake as strongly as other groups thought. For example, factory managers viewed factory pollution as negatively affecting the lake but less strongly than the other groups did. According to policy option simulations, reducing lake pollution had positive effects on all variables, especially fish, birds, animal husbandry, irrigation, agriculture, and the ecological balance of the lake. Results of this analysis were used to facilitate meetings among stakeholder groups and to develop a participatory ecosystem management plan. The analysis was useful for pointing out the similarities as well as the differences among the groups. It also helped the facilitators understand the focus of each stakeholder group and enabled them to suggest activities in which each group would want to participate.     

Lake rehabilitation: A status report

The widespread recognition of lake degradation as a major environmental concern has led to accelerated efforts to better protect and manage lake resources. Where it is too late for avoidance strategies, lake rehabilitation is receiving increasing attention as a natural resources management option. In recent years, a significant number of lake rehabilitation experiences has been documented throughout the world, and many nations and states have embarked upon major lake rehabilitation programsLake rehabilitation is not a ready-to-go technology at this time and still must be regarded as partly experimental. Nevertheless, there have been a number of notably successful lake rehabilitation experiences. Reducing or halting the influx of undesirable materials is the sine qua non for lake rehabilitation. In most successful experiences to date, this has been accomplished by diversion and/or wastewater treatment. A number of in-lake strategies have also been employed to rehabilitate degraded lakes, often as part of an overall restoration plan. Techniques that appear to be most useful include dredging and nutrient inactivation. Several examples of successful applications are noted.Although efforts to rehabilitate lakes have produced a mixed record, there are encouraging results that suggest the viability of this approach. Lake rehabilitation, however, is no substitute for environmental management strategies that provide for protection of lake ecosystems in the first place.     

REMOTE MONITORING OF SELECTED GROUND‐WATER DOMINATED LAKES IN THE NEBRASKA SAND HILLS1

ABSTRACT: The Landsat‐Muitispectral Scanner (MSS) data were used to measure lake area fluctuations (1972–1989) for 130 ground‐water dominated lakes in the Western Lakes Region of the Nebraska Sand Hills. In general, the pattern shown in lake area hydrographs was similar to that for in‐situ lake elevations. In‐situ lake‐elevation data verify that remote monitoring of surface‐area fluctuations, even at relatively coarse spatial resolution, is not only practical and useful, but also it elucidates the hydrologic characteristics of groundwater‐dominated lakes of the Sand Hills. The apparent differences in behavior between lakes in the northern and southern portions of the study area may be related to both their location in the regional ground water system and the substantial local hydrologic complexity.     

东洞庭湖世界涉危鸟类多样性的分析研究

为了探讨湿地自然保护区综合措施的实施对鸟类多类性的影响,本文分析比较了东洞庭湖自1992年加入国际《湿地公约》后,在1992-1996年间世界濒危鸟类多样性的动态变化。自1992年加入国际《湿地公约》后,尽管对洞庭湖湿地及其内栖息的生物采取了诸多保护措施,但仍发现世界濒危鸟类多样性的值并未如人们所期望迅速有所回升,而是呈弱递减趋势。东洞庭湖湿地的世界濒危鸟类多样性大小状况为:1992-1993>1993-1994>1994-1995>1995-1996。因为湿地环境的客观改善勿容质疑,为此得出结论:鸟类多样性的恢复存在滞缓期。并且作者对退化湿地生态系统的恢复途径进行了讨论,提出合理化建议:(1)应该根据湿地演替的规律进行认为辅助演替。(2)保证湿地环境的稳定性,增加净生产力,使鸟类的基础饵料丰富充足。