余氯对水生生物的影响

氯是滨河、滨海企业冷却水常用的防治污损生物的处理剂。总结近年来国内外氯在企业冷却水中的应用、氯对浮游植物、浮游动物、贝类、鱼类等影响的研究成果,为制定冷却水余氯排放标准和水产养殖的合理布局提供了参考,针对我国大量滨海电厂即将建立的现状,分析了余氯研究在中国海域研究的不足,提出了氯对我国海洋生物影响不同层面的研究方向。认为氯对生物种群的毒性,氯对生物群落组成、结构和生态演替的影响,以及减轻或避免余氯污染的对策是需要进一步解决的科学问题。     

环境因素对鱼类某些生理机能的影响

鱼类生态生理学是渔业生产的重要理论基础,它是研究外在环境因素对鱼类机体的生理机能的影响以及鱼类对环境变化的生理适应过程,近年来发展很快。本文着重介绍环境因素,主要是温度和水污染物对鱼类呼吸、代谢、血液、心脏等机能的影响,并对加强鱼类生态生理学研究的重要性和利用鱼类对水污染物的反应特性作为生物监测手段的问题进行了论述。     

安徽龙窝湖细鳞斜颌鲴的球孢虫病

细鳞斜颌鲴(Plagiognathops microlepis以下简称斜颌鲴)。俗名:黄条、黄尾、沙姑子等。原系野生鱼类,七十年代经水生生物研究所驯化繁育,已成为淡水养殖新品种。据有关方面统计,全国有十九个省、市、自治区试养成功,鄂、赣、湘、苏等省还取得生产性效果,深受群众欢迎。 斜颌鲴疾病较少,初步了解,国内发现的有     

叔丁基对羟基茴香醚和诺氟沙星对水生生物的影响

采用急性毒性试验的方法,研究了叔丁基对羟基茴香醚(Butylated hydroxyanisole,BHA)和诺氟沙星(Norfloxacin,NFLX)对水生生物斜生栅藻和大型溞的毒性效应。结果表明大型溞在BHA和NFLX暴露下48h的LC₅₀分别为3.15mg·L^-1和194.98mg·L^-1。BHA和NFLX对斜生栅藻也有明显的毒性作用,其96h的EC₅₀分别为6.19mg·L^-1和50.18mg·L^-1。大型蚤对BHA暴露的敏感性强于斜生栅藻,而斜生栅藻对NFLX的敏感性比大型溞强。根据化学物质对鱼类和溞类的毒性评价标准,BHA和NFLX分别属于中等和低等毒性的化合物。     

洞穴鱼类——神秘地下世界的定居者

洞穴对于生物来说是一种极端环境,却孕育了一些鲜为人知的特殊生物,洞穴鱼类就是其中的典型代表。依据是否具有洞穴适应特征,洞穴鱼类可分为典型和非典型两大类型。中国是世界上洞穴鱼类物种多样性最丰富的国家,拥有130种有效种,其中有69种为典型洞穴鱼类。受岩溶发育和气候等影响,中国绝大多数洞穴鱼类分布在广西、云南、贵州3个省、自治区。中国的洞穴鱼类面临着严峻的生存威胁,人类经济发展造成的洞穴和地下水环境退化是最主要的威胁因素。     

体重对斜带石斑鱼能量收支的影响

鱼类能量学是研究能量在鱼体内转换的学科,其核心问题之一是能量收支各组分之间的定量关系及其各种因子(如温度[1—5]、盐度[6]、体重[7—11]、性别[12]、摄食水平[13—18]、饵料种类[19,20]等)的影响作用。欧美等发达国家对鱼类能量学研究起步较早,迄今已经初步建立了多种鱼类的能量收支模式[21,22];国内在该领域较系统的研究起始于90年代初[23—25],主要局限于淡水鱼类,近年来又对海水鱼类进行了大量研究[26]。斜带石斑鱼(Epinephelus coioides)俗称青斑,为暖水性中下层鱼类,是广东省海水网箱养殖的主要品种之一。斜带石斑鱼分布于西太平洋的硫球群岛、澳大利亚以及贝劳和菲济群岛的东部,常栖息于大陆沿岸和大岛屿,但在河口和离岸100m深的水域中也可发现[27]。通过本项研究将有助于揭示海洋暖水性中下层鱼类的能量学特征。1材料与方法1·1材料来源与驯养实验用斜带石斑鱼,采自广东省大亚湾水产试验中心。实验用斜带石斑鱼经淡水浸泡10min后,置于室内容积0·5t桶内驯养,待摄食和生长趋于正常后,开始实验。驯化时间为30d。实验于2006年10—11月在广东省大亚湾水产试验中心进行。1...     

城镇化背景下深圳典型流域鱼类群落特征及驱动因子

理解城镇的快速发展对河流鱼类群落结构的影响,是城镇河流科学管理和生物多样性保护的关键基础。本研究于2019年丰水期（8月）和枯水期（11月）,选取我国城镇化典型城市-深圳域内两个处于不同城镇化程度的代表性流域,应用多重统计方法比较分析了流域间鱼类群落结构的差异,并探讨了驱动鱼类群落变异的关键环境要素。结果发现,城镇化程度高的观澜河流域其鱼类种类组成、优势类群、生物多样性指数与城镇化程度低的坪山河流域有明显差别。 具体表现为：城镇化程度高的流域土著敏感种类如异鱲、吸鳅等几近消失,优势类群为外来入侵耐受种类,其物种多样性显著低于城镇化程度低的流域（P<0.05）。同时,外来鱼类在城镇河段其数量占比平均达92.5%,广泛分布于深圳城镇河流中。在环境因素方面,城镇化程度高的观澜河流域水体理化指标总氮、总磷、氨氮、化学需氧量、生化需氧量、高锰酸盐指数均显著性高于城镇化程度低的坪山河流域（P<0.05）。基于Bray-Curtis距离的冗余分析显示：城镇用地占比和总氮是影响观澜河和坪山河流域鱼类群落差异的主要因素。城镇化进程中河流生境的改变已影响到土著鱼类的生物多样性。因此,推动以恢复土著鱼类生物多样性的河流生态治理与保护是今后水生态目标管理的重要方向。     

水生生物对重金属吸收和积累研究进展

综述了国内外在水生生物对重金属吸收和积累研究方面的最新进展。着重阐述了重金属毒性影响因素和鱼类对重金属吸收和积累机理方面的研究现状和趋势。     

海南万宁海域海洋生物重金属分析与评价

海洋经济生物体内重金属含量直接影响到人类健康。根据2020年12月对万宁海域12个调查站、10种生物(鱼类7种、软体类1种、甲壳类2种)体内的7种重金属(Cu、Pb、Zn、Cd、Cr、As、Hg)含量监测结果,分析了重金属的含量特征,并分别利用单因子污染指数法和重金属富集系数对重金属污染水平和它在生物体内的富集情况进行了评价。结果表明:(1)各类生物体内重金属含量的高低顺序不一致,但三类生物体内锌和铜的含量均相对较高。生物对必需元素锌和铜的富集明显高于对非必需元素铅、镉和总汞的,主动吸收能力明显。(2)不同类生物同种重金属的含量存在一定差异,甲壳类的高于鱼类和软体类的。万宁海域鱼类和软体类生物重金属单因子污染指数均小于1,部分甲壳类生物的铬单因子污染指数大于1,超标率为41.7%。铬是万宁海域海洋生物的主要污染因子,影响其含量的原因可能是周围的围填海工程,以及所研究物种的生理特性。(3)万宁海域甲壳类生物体内总汞已呈轻污染状态,铬呈重污染状态。(4)甲壳类生物对重金属的富集能力强于鱼类和软体类的,各类生物对Cu的富集能力最高,对As的富集能力最低,且对重金属Cu、Cd和Zn有潜在的严重...     

外来养殖鱼类的入侵风险评估及防控对策——以尼罗罗非鱼为例

[目的]筛选合适的指标建立一套外来养殖鱼类的生物入侵风险评估体系,并对外来养殖鱼类的生物入侵防控提出对策建议。[方法]通过文献资料的收集和整理,对外来养殖鱼类中典型入侵物种的入侵过程、影响危害和入侵生物学特性进行分析和归纳,从适应能力、繁殖能力、扩散能力3方面指示其入侵性;从对生物的影响和对环境的影响2方面指示其生态影响;从自然因素和人为因素2方面指示环境可入侵性,以上述3方面为框架进行评估体系构建。[结果]筛选20个指标构建了外来养殖鱼类的生物入侵风险评估体系,并举例说明该评估体系的应用。从法规政策、科学研究、治理技术和公众参与等4个方面针对性地提出外来养殖鱼类生物入侵风险防控对策。[结论]防范和治理入侵生物是一个系统工程。对于外来养殖鱼类的管理,既不能只考虑经济效益而置生态风险于不顾,也不能片面放大外来养殖良种的入侵风险。科学管控的关键在于完善制度建设、加强风险评估、发展防治手段、促进公众参与,使外来鱼类养殖业在严格受控的前提下发挥其经济效益,将其潜在的生态危害效应降到最低。     

Changes in plant species diversity of aquatic ecosystems in the agricultural landscape in West Poland in the last 30 years

The aim of this study was to diagnose changes in species composition and their dynamics caused by human impact in aquatic and marsh vegetation in the contemporary agricultural landscape. The most serious threat was an increase in the nitrogen content of surface waters and groundwater which had resulted from the intensive management of the surrounding areas. Floristic data were collected in a lake, peaty pools and a drainage ditch within agricultural areas in the Wielkopolska region (West Poland) in 2006–2007, and compared with data from 1976–1980. The species richness had significantly increased and the shares of sociological and geographical–historical groups had changed clearly. This was reflected in an increase in the synanthropization index from 32.6 to 48.5. All the changes resulted from human impact, which had caused the acceleration of eutrophication in the water bodies. The natural plant succession, especially in the reed beds and sedge communities, was also accelerated due to human pressure. The vascular plant species richness in aquatic and marsh habitats increased by 40, because 15 species had disappeared and 55 new had appeared. However, six moss and four stonewort species had disappeared and only three new moss species were found. The increase in species richness did not raise the natural value of the flora, because the new species group is composed mainly of synanthropic species: native (apophytes) and alien, whereas all the lost species are endangered and rare native species (spontaneophytes), which occur only in natural or seminatural conditions. On the local scale, as species richness increases, plant communities lose their natural value. As an effect of synanthropization the stenotopic species disappear, while the widespread species spread even more. The increase in species richness is a consequence of appearance of species with a wide ecological scale that are not typical for aquatic ecosystems in patches of emergent vegetation. Finally, the species diversity of the whole landscape declines.     

Facilitating the restoration of aquatic plant communities in a Ramsar wetland

Human activities such as land clearing and intensive land use around water bodies, particularly wetlands, have a detrimental impact on water quality and quantity, aquatic plant communities, and associated wetland fauna. Lake Alexandrina and Lake Albert are internationally significant Ramsar wetlands located at the terminus of the Murray River, Australia's longest river system. Agriculture, water regulation, and extraction and droughts have had a detrimental impact on native plant communities in the lakes. We studied the influence of young (<1–3 years) and old (8–11 years) plantings of a native sedge (bulrush), Schoenoplectus tabernaemontani, to facilitate the establishment of aquatic plant communities in comparison with remnant and control sites. We also measured how planting structure (height, stand width, and stem density) changed with age in comparison with remnant sites. Results suggest that as plantings age they get substantially wider and have a greater maximum height, although do not reach similar stand widths by 11 years when compared to remnant areas. However, old plantings do not differ from remnant habitats in relation to aquatic plant species richness, counts of aquatic plants, and community composition. Young plantings have substantially less abundant and diverse plant communities, but are developing on a similar trajectory to old plantings. It is likely that planting sedges along lake shorelines causes a breakwater effect that facilitates the recolonization of wetland plants between the planted area and the water's edge. Management agencies should consider restoring native sedges to increase aquatic biodiversity, and potentially reduce erosion.     

Measures to develop a rich-fen wetland landscape with a full range of successional stages

Species-rich plant communities characteristic for succession from mesotrophic open water to fen are very rare in The Netherlands. These vegetation types used to occur in turf ponds in the low lying peatland area, created by peat dredging and filled with water due to seepage of mesotrophic, well-buffered groundwater. One of the goals of the National Nature Policy Plan is to create new opportunities for the initial terrestrialization communities through ecological engineering, e.g., restoration and creation of open water habitats. Restoration of the abiotic conditions in acidified floating fen communities is only possible by a combined measure of removal of the Sphagnum-layer and superficial drainage of surplus rain water. New turfponds have been excavated. This study showed that the abiotic conditions (i.e., water depth and water chemistry) are favorable for the development of aquatic communities characteristic of mesotrophic conditions. The aquatic plant species found in the new ponds also point in this direction, e.g., Chara major and Ch. delicatula are very abundant as are seven Potamogeton species. It is concluded that a constant discharge of groundwater and a good connectivity between the ponds and the existing remnants of plant communities desired in the area are essential for the conservation and development of these species-rich plant communities.     

干旱对湖北省长湖水生植物多样性的影响

将断面法和地理信息系统（GIS）与全球定位系统（GPS）技术相结合,通过比较湖北省长湖2000年（干旱年）与1999年（非干旱年）的水生植物多样性,探讨了干旱对淡水湖泊水生植物多样性的影响,主要结论如下：（1）干旱对长湖淡水湖泊水生植物物种多样性无影响,但可增加优势种数目（从12个至14个）。（2）干旱使长湖水生植物群丛数目从14个增加至18个,且能显著提高各群丛的Simpson与Shannon-Wiener物种多样性指数。（3）干旱显著提高了长湖水生植被覆盖率与各群丛的盖度,并使全湖水生植被平均单位面积生物量与各群从单位面积生物量显著升高。（4）在干旱年（2000年）,长湖挺水植被消失,但浮水植被面积与沉水植被面积显著扩大：分别从1999年的3.71％与41.32%上升至2000年的12.63%与53.84%（占湖泊总面积的百分比）。（5）干旱条件下淡水湖泊水生植物的生长发育明显加快：2000年7月菹草石芽萌发率、菹草幼株长度和野菱黄叶率显著高于1999年同期值。     

The impact of eutrophication on aquaticmacrophyte diversity in weakly mineralized streams in the Northern Vosges mountains(NE France)

The relationships between water chemistry and aquatic macrophyte species were studied in an attempt to evaluate the impact of eutrophication on aquatic macrophyte diversity in weakly mineralized streams in the Northern Vosges mountains (NE France). The macrophyte specific richness and abundance increased along an upstream to downstream zonation, which was characterized by an increase in mineralization and nutrient levels. A comparison of aquatic macrophyte diversity of two streams has shown the impact of human-induced perturbations (fish-farms, domestic sewage) in such weakly mineralized and poorly buffered waters. Disturbed sites with very high nutrient loading were characterized by a low vascular plant richness and by the presence of filamentous algae. In order to preserve the floristic diversity of weakly mineralized streams, water quality should be improved, the riverbanks restored and discharges reduced.     

高原湿地纳帕海水生植物群落分布格局及变化

采用3S技术与植物群落研究法,对高原湿地纳帕海24a来的湿地植物群落分布格局及变化的研究结果表明：与24a前水生植物群落相比较。纳帕海水生植物群落类型、数量改变,原生群落不断减少或消失,耐污、喜富营养类群如水葱群落（Com．Scirpus tabernaemontani）、茭草群落（Com．Zizania caduciflora）、穗状狐尾藻群落（Com．Myriophyllum spicatum）、满江红（Com．Azolla imbricata）群落等大量出现;群落总数由24a前的9个增至当前的12个,其中挺水植物群落增加2个,浮叶植物群落增加1个,挺水植物群落增幅最大。由东向西、由南向北,纳帕海水生植物群落分布大致呈现出浮叶群落、挺水群落、沉水群落斑块状依次配置的水平格局规律。挺水植物群落分布面积最大,达528．42hm^2,其次是沉水植物群落,分布面积为362．50hm^2,浮叶植物群落分布面积最小,为70．23hm^2。随沉水群落、浮叶群落向挺水群落的演替,群落伴生种数量增加、优势种优势度减小、层次类型改变,群落结构变得更为复杂。纳帕海湿地水生植物群落分布格局及变化是对湿地环境变化的响应,表明了在人为干扰作用影响下,纳帕海湖岸线内移、水量减少、水质恶化等湿地水文条件的改变,致使湿地生态系统功能不断退化。     

河套灌区六排域植物物种多样性研究

为了研究河套灌区六排域植物物种多样性。于2010 年8-9月进行调查, 以排沟等级为原则, 在干沟、支沟、斗沟或农沟的上、中、下游设置调查断面, 每断面沿沟道垂直剖面从沟底到边坡共设置0.5 m 0.5 m的草本样方101个、边坡设置5 m 5 m的灌木样方22个, 调查样方内的植物种类和数量。研究结果表明, 河套灌区六排域植物由22个科, 41个属, 43个种组成; 其中禾本科、菊科和豆科植物所占比重最大; 植物群落主要以芦苇为主的草本组成型; 干沟、支沟和斗/农沟的多样性指数、优势度指数、丰富度和均匀度指数值分别为0.79、0.37、3.20和0.55, 0.90、0.54、4.37和0.62, 0.89、0.53、4.25和0.63。随着排沟等级的降低, 多样性指数值随之增加; 边坡较沟底有明显较高的物种多样性。       

在水生与气生状态下石莼光合作用对光照和温度的响应

如何对付由于高潮时的水生状态与低潮时的气生状态高频率循环所导致的不同环境条件,是潮间带海藻的光合作用所面临的独特问题。对采自汕头沿岸的石莼(Ulva lactuca)在水生和气生不同状态下光合作用对光照和温度的响应特性进行了测定,以探讨这种常见的潮间带绿藻在潮汐循环背景下的光合特性。在气生状态下,光饱和净光合速率(Pmax)随气生暴露时间的变化模式可以很好地用三次方程进行描述,而温度影响方程的系数;当水分损失为15％时,石莼的Pmax增加至最大值,然后Pmax随进一步脱水而下降,在水分损失为80％时下降至0。温度对Pmax的影响在水生状态下比在气生状态下更大。气生状态下（充分水化）Pmax在10℃时显著小于水生状态下的值,而在30℃时则相反。在10℃时,气生干出时间在6 h 以内,或在20℃时,气生干出时间在2.2 h 以内,石莼的净碳固定量在气生状态下比在水生状态下要大;而在30℃时,在气生状态下的净碳固定量比总是小于在水生状态下的净碳固定量。认为石莼在低潮气生状态下与在高潮水生状态下光合特性及净碳固定存在差异,但这种差异与环境温度及叶状体的水分状态有关。     

The Impact of Conservation Management on the Community Composition of Multiple Organism Groups in Eutrophic Interconnected Man-Made Ponds

Ponds throughout the world are subjected to a variety of management measures for purposes of biodiversity conservation. Current conservation efforts typically comprise a combination of multiple measures that directly and indirectly impact a wide range of organism groups. Knowledge of the relative impact of individual measures on different taxonomic groups is important for the development of effective conservation programs. We conducted a field study of 28 man-made ponds, representing four management types differing in the frequency of periodic pond drainage and the intensity of fish stock management. We disentangled the relative importance of direct and indirect effects of pond management measures on the community composition of phytoplankton, zooplankton, aquatic macro-invertebrates, submerged and emergent vascular plants. With the exception of phytoplankton, pond management had strong effects on the community composition of all investigated biota. Whether management affected communities directly or indirectly through its impact on fish communities or local environmental conditions in the pond varied between organism groups. Overall, the impact of pond drainage regime and fish community characteristics on the community composition of target organism groups were more important than local environmental conditions. The majority of taxa were negatively associated with fish density, whereas multiple emergent plant species and several taxa of aquatic macro-invertebrates were positively affected by increased drainage frequency. The effects of fish community and drainage tended to be largely independent. The present study indicates that pond drainage is an important element for biodiversity conservation in eutrophicated shallow and interconnected man-made ponds.