滆湖轮虫群落结构与水质生态学评价

研究了浅水湖泊--滆湖的轮虫群落结构,并用轮虫污染指示种类、E/O值、QB/T值和生物多样性指数评价滆湖的水质和营养状况.在两周年的研究中,共发现轮虫69种,污染指示轮虫39种.优势种为萼花臂尾轮虫(Brachionua calyciflorus)、前节晶囊轮虫(Asplanchna priodonta)、针簇多肢轮虫(Polyarthra trigla)、长三肢轮虫(Filinia longiseta)和裂足臂尾轮虫(B.diversicornis).轮虫密度年平均值为1584 ind./L,生物量年平均值为5.982 1 mg/L.密度秋季最高,生物量夏季较高.轮虫物种多样性较低,多样性指数与其密度及生物量正相关.滆湖三个生态功能区轮虫的种类相似;湖区北部与中部的轮虫现存量差异不显著,与南部的差异显著,中部与南部间差异极显著.根据指示生物法、生物指数法和多样性指数法评价滆湖水质及营养类型,涌湖为富营养型.     

湖泊富营养化对轮虫群落结构及物种多样性的影响

2005年7月至2006年6月, 我们对安徽省芜湖市境内5个湖泊中轮虫的群落结构及部分水质特征参数进行了调查, 用相关加权综合营养状态指数(TLIc)评价了各湖泊的营养水平, 分析了其中的轮虫群落结构、多样性指数及其与TLI_C之间的关系。经鉴定, 5个湖泊中共采集到轮虫79种, 隶属18科31属; 不同营养水平湖泊中出现的轮虫种类数有明显的差异(P<0.01)。除龙窝湖外, 其余4个湖泊中的轮虫种类数与TLI_C均呈显著负相关关系(r＝–0.984, P<0.05)。湖泊水体的富营养化进程显著地提高了轮虫总密度和第一优势种的优势度, 降低了轮虫群落的均匀度和物种多样性指数。     

淮北煤矿区塌陷湖大型底栖动物群落结构及水质生物学评价

2013年对淮北采煤塌陷湖(乾隆湖和临涣湖)大型底栖动物群落结构进行了季节性调查。共采集到大型底栖动物26种, 隶属于3门5纲17科. 乾隆湖和临涣湖年平均密度分别为230.85和215.80 ind./m2, 年平均生物量分别为56.11和36.38 g/m2。两湖大型底栖动物以摇蚊幼虫、霍甫水丝蚓和苏氏尾鳃蚓为优势类群, 底栖动物最高密度均出现在夏季(乾隆湖为 278.0 ind./m2, 临涣湖为288.2 ind./m2); 生物量则主要以软体动物和水生昆虫为主, 夏季和秋季大型底栖动物生物量明显高于春季和冬季。运用Shannon多样性指数(H')、Margalef多样性指数(D)和Biotic Index生物学指数(BI)对乾隆湖和临涣湖进行水质生物评价研究, 结果显示Shannon多样性指数不适宜于该两湖的水质生物评价, BI的评价结果与水质状况基本相符。综合 Margalef多样性指数和BI生物指数评价的结果表明: 乾隆湖和临涣湖春季和冬季处于轻度污染状态, 夏季和秋季处于中度污染状态。     

湖北四湖泊营养类型与轮虫群落的关系

对湖北梁子湖水系不同营养类型(中营养型、富营养型)4个湖泊中轮虫的群落结构和物种多样性进行了周年研究,分析比较了不同营养类型湖泊的轮虫种类组成、分布、优势种组成、密度、生物量和多样性指数。结果表明：轮虫的种类数、物种多样性与营养水平呈负相关关系,轮虫密度大体上随营养水平提高而增大,富营养化引起轮虫空间异质性降低,受污染湖泊与非污染湖泊轮虫种类数、寡污性种类数及分布差异尤为明显。用多样性指数评价湖泊营养状态与TLIc方法一致。     

吉安地区典型景观湖泊浮游植物群落特征及其与水环境因子的关系

2012年8月至2013年7月,对吉安地区将军湖、龙湖、庐陵湖和挹翠湖4个景观湖泊水体浮游植物群落及其主要水环境因子进行了调查,并利用生物多样性指数法(Shannon指数H、Margalef指数D和Pielou指数J)和主成分分析(PCA)法分别对湖泊水质和水环境因子进行了评价。结果表明:4个湖泊共鉴定浮游植物7门82属163种,主要优势种为硅藻或绿藻;浮游植物细胞丰度呈季节性变化,秋夏居高,冬春季偏低,平均丰度变化范围为25.45×10~6~54.04×10~6cells·L~(-1);将军湖、龙湖、庐陵湖和挹翠湖的H值分别为1.26~2.08、1.82~2.61、2.27~2.62和1.10~2.32;D值分别为2.03~3.51、2.36~3.71、2.48~3.93和3.12~3.96;J值分别为0.45~0.69、0.59~0.80、0.67~0.77和0.50~0.84。综合评价结果显示,4个湖泊处于富营养化状态、中等污染水平。而对污染较重的庐陵湖水环境因子PCA分析结果表明,水温(WT)、溶解氧(DO)和总氮(TN)是影响小型封闭景观水体浮游植物群落变化的主要因素。建议对小型封闭景观水体进行必要的治理和生态修复。     

以浮游植物评价达赉湖水质污染及营养水平

1987—1988年在30个样点,四季采样,对达赉湖的浮游植物进行了种类组成,生物量、种群数量、优势种、污染指示种、硅藻指数、综合指数等群落生态学的初步研究,应用后五项参数对达赉湖水质污染及营养水平进行了评价。达赉湖浮游植物年均值达54.7×106个/L(细胞数,或个体数为2.3×106个/L),硅藻指数为149.3,综合指数为5.6。群落组成中污染指示种占65%,春季以绿藻的十字藻、卵囊藻为优势种,其它3个季节均以蓝藻中的微囊藻、鱼腥藻、腔球藻占优势,表明达赉湖已受到中等程度污染,属于蓝、绿藻型富营养湖。       

汉城湖浮游动物群落结构特征及与水质关系

为了探究陕西西安汉城湖浮游动物群落结构特征及与水体营养化水平关系, 于2015 年的3、6、9 和12 月份对汉城湖浮游动物进行了调查研究, 运用丰度、生物量、E/O 指数、Q_B/T 指数、E 指数、S 指数、多样性指数和综合营养状态指数(TSI)评价水体营养化程度, 应用典范对应分析法(CCA)分析了环境因子与浮游动物的相关性, 结果显示:共检测出浮游动物21 属28 种, 其中原生动物3 种, 轮虫21 种, 枝角类2 种, 桡足类2 种, 浮游动物丰度为17-48 个·L^-1,生物量为0.012-0.058 mg·L^-1, 优势种有20 种; 丰度和生物量显示水体处于贫营养状态, E/O 指数、Q_B/T 指数、肥度指数(E)和综合营养状态指数(TSI)均显示水体为富营养型, 污生指数(S)和多样性指数显示水体为中营养型, 综合结果表明, 汉城湖整体处于中-富营养水平; 水温、总氮、溶解氧、叶绿素a 和透明度是影响汉城湖浮游动物种群结构的主要环境因子。     

富营养化对小型湖泊浮游甲壳动物群落结构及多样性的影响

2017年3月到2018年2月研究了临涣湖浮游甲壳动物群落结构的季节变化。临涣湖共记录浮游甲壳动物13种,其中枝角类8属8种,桡足类5属5种。短尾秀体溞(Diaphanosoma brachyurum)、广布中剑水蚤(Mesocyclops leuckarti)和象鼻溞(Bosmina sp.)等小型富营养种类是温暖季节的优势种,而近邻剑水蚤(Cyclops vicinus)是冬季的优势种。盔形溞(Daphnia galeata)等大型种类仅在少数月份中被观察到。临涣湖浮游甲壳动物的年平均密度和生物量分别为28.3个/L和0.33 mg/L。营养状态指数(TSI_M)的年平均值为62.6。浮游甲壳动物的Shannon指数、Pielou指数和Simpson指数的年平均值分别为0.86、0.74和0.49,且3种多样性指数均具有显著的季节差异。营养盐水平、营养状态指数和物种多样性指数均表明,临涣湖水体处于富营养化状态。冗余分析结果表明,水温、总磷浓度和叶绿素a浓度是影响临涣湖浮游甲壳动物群落结构变化的上行效应因子。鲢、鳙鱼的捕食压力是临涣湖浮游甲壳动物群落结构小型化的下行效应因子。     

以浮游植物评价巢湖水质污染及富营养化

对巢湖浮游植物在22个样点,四季采样,进行了种类组成、种群数量、优势种、污染指示种,多样性指数及硅藻指数等群落生态学的初步研究。选用其中种群数量、优势种、污染指示种、硅藻指数对巢湖水质污染及营养水平进行了总评与分区评价。就巢湖总体而论,藻量年均值达111×10~6个/升(细胞数,或个体数为14.7×10~6个/升),硅藻指数96.7,群落组成种类中,污染指示种占64.2％,除冬季外,各样点多以微囊藻、鱼腥藻为主的蓝藻占优势,其分布频度年平均达98.8％,多度年平均达79.7％,而在夏、秋季,两者则分别为100和99.7％,表明巢湖已受到中等程度的污染,属蓝藻型富营养湖泊;与过去巢湖浮游植物的调查资料对比,表明最近几年来,人为富营养化进程在加速。     

河北衡水湖自然保护区水鸟多样性分布格局及其保护优先区

水鸟是反映湿地生态系统状况的指示物种,水鸟多样性保护优先区识别对自然保护区功能区划和湿地保护修复具有重要意义。于2020年5月-2021年4月,开展了衡水湖自然保护区水鸟群落的调查监测,采用GIS软件和结构方程模型等分析其不同区域水鸟群落结构和季节性变化、水鸟多样性分布格局及其驱动因素。结果表明:(1)衡水湖自然保护区不同区域均表现出以雁鸭类等游禽为优势种的水鸟群落特征,衡水湖西湖和滏东排河的水鸟物种丰富度和Shannon多样性指数最高,衡水湖东湖的水鸟种群数量最大,滏阳新河的鸻鹬类种群数量相对较大。(2)不同区域水鸟群落具有明显的季节性变化特征,春夏季涉禽数量明显增多,但仅在衡水湖自然保护区东湖、西湖和滏阳新河成为水鸟群落的优势种;9月之后各区域游禽种数和种群数量占比均明显上升,雁鸭类成为优势种群。(3)水鸟物种丰富度和种群数量较高的区域主要在自然保护区的湿地恢复区、滏东排河和小湖隔堤两侧等地;不同类群水鸟的空间分布格局差异较大,雁鸭类分布较为分散,鸻鹬类、鹤鹳类水鸟分布更为集中;栖息地状况是影响衡水湖水鸟多样性的主要因素。(4)衡水湖水鸟保护优先区包括湿地恢复区及周边区域、南李庄鱼塘、良心庄鱼塘及周边区域、东湖的姊妹东岛、小湖隔堤两侧等5个区域,占保护区总面积的8.94%。研究结果为衡水湖自然保护区的功能区划、水鸟保护策略制定、栖息地保护修复提供了相关依据。     

Macroinvertebrate Diversity in Alpine Lakes: Effects of Altitude and Catchment Properties

Lakes are common features of alpine landscapes, and the attention given to alpine lakes has increased recently in response to increased recognition of the important role that these freshwaters play as sensible indicators of climate change. Despite this general research interest, there is nevertheless a general lack of information about zoobenthos especially of lakes in the Alps, and only few published data are available, which has made it nearly impossible to draw general conclusions in respect to benthic community structure, profundal and/or littoral food webs. This paper aims to explore the relationships between main environmental/catchment properties of 55 lakes and their littoral benthic fauna across three regions of the Alps. We provide updated information on relative abundance, species richness, distribution and ecology of macroinvertebrates which occur and are typical in the littoral of high-mountain lakes of the Alps. These lakes were located in the Lago-Maggiore Watershed (Italy and Switzerland), in South Tyrol (Italy) and in North/East Tyrol (Austria), between 1840 and 2796 m a.s.l., in catchments undisturbed by human activities. As the studied lakes are situated above the tree line, they were characterised by low nutrient levels indicating an oligotrophic status. Lake water chemistry corresponded closely to the geo-lithology of the catchment and some parameters (especially nutrient concentrations) differed between the regions. The macroinvertebrates were dominated by insects which to a high degree were chironomid larvae and pupae. Other insect orders were typical cold stenotherm species of Ephemeroptera, Plecoptera and Trichoptera. Non-insect macroinvertebrates contributed to the 144 taxa found. Other than lake size and catchment area, the faunal parameters exhibited a clearer pattern along altitude. Macroinvertebrates per sample increased with higher elevation, reached their maximum in lakes between 2400 and 2600 m a.s.l., but decreased strongly above 2600 m. The altitudinal pattern of species richness and Shannon diversity resembled each other being highest between 2001 and 2200 m a.s.l., but decreased when going lower and higher, respectively. Various patterns and trends along altitude were also evident when individual groups were analysed within the individual sampling regions. The somewhat conflicting trends of various biocoenotic indices let assume that factors other than altitude are also responsible for the structure of faunal assemblages in the littoral of alpine lakes. Six variables (“bare rocks” and “nitrate”, “alkalinity”, “ammonia” and “peat bog”) were selected by the CCA analysis where these three groups of lakes were identified: (1) lakes with a higher alkalinity (higher pH, conductivity, ion concentration), a higher relative vegetation cover (compared to the “bare rocks” on the opposite side) and lower nitrate levels; (2) lakes with a higher portion of “bare rocks” in their catchments and higher nitrate levels; and (3) a smaller group of lakes with higher ammonia levels and a boggy environment. Geographical patterns seemed to have weak effects on the presence of taxa while catchment properties had evident impacts on macroinvertebrate communities in these lakes. In this way, the present study contributes to the overall understanding of environmental settings and effects on high mountain lake ecosystems and assists in refining research and conservation strategies for an important landscape aspect in the Alps.     

Response of benthic macroinvertebrates to whole-lake, non-native fish treatments in mid-elevation lakes of the Trinity Alps, California

Introduced fish reduce the abundance and diversity of native aquatic fauna, but the effect can be reduced in complex habitats. We manipulated fish populations in forested mountain lakes to determine whether or not fish affected benthic macroinvertebrate composition across lakes with differing habitat complexity. We compared abundance, biomass, body-length, and community structure of benthic macroinvertebrates from 16 lakes with three treatments (fish stocked, suspended stocking, fish removed) and unstocked fishless “controls”. Over 4 years, we assessed the relative importance of fish and environmental variables influencing the composition of benthic macroinvertebrates. Control lakes had the greatest overall abundance of macroinvertebrates when chironomid midges were excluded. Abundances of insects in the clinger/swimmer functional group and caddisflies were greatest in the control lakes but were primarily influenced by habitat variables including the availability of aquatic vegetation and wood. Total biomass and mean body length of macroinvertebrates were not affected by treatment. Taxon richness of macroinvertebrates was about 40% greater in the control lakes compared to the treatment lakes but did not differ among treatments. Our results suggest that fish reduce susceptible macroinvertebrate richness and abundances, but that changes associated with alterations of fish composition are confounded by other factors in complex lake habitats.     

Interpreting ecological diversity indices applied to terminal restriction fragment length polymorphism data: insights from simulated microbial communities

Ecological diversity indices are frequently applied to molecular profiling methods, such as terminal restriction fragment length polymorphism (T-RFLP), in order to compare diversity among microbial communities. We performed simulations to determine whether diversity indices calculated from T-RFLP profiles could reflect the true diversity of the underlying communities despite potential analytical artifacts. These include multiple taxa generating the same terminal restriction fragment (TRF) and rare TRFs being excluded by a relative abundance (fluorescence) threshold. True community diversity was simulated using the lognormal species abundance distribution. Simulated T-RFLP profiles were generated by assigning each species a TRF size based on an empirical or modeled TRF size distribution. With a typical threshold (1%), the only consistently useful relationship was between Smith and Wilson evenness applied to T-RFLP data (TRF-E(var)) and true Shannon diversity (H'), with correlations between 0.71 and 0.81. TRF-H' and true H' were well correlated in the simulations using the lowest number of species, but this correlation declined substantially in simulations using greater numbers of species, to the point where TRF-H' cannot be considered a useful statistic. The relationships between TRF diversity indices and true indices were sensitive to the relative abundance threshold, with greatly improved correlations observed using a 0.1% threshold, which was investigated for comparative purposes but is not possible to consistently achieve with current technology. In general, the use of diversity indices on T-RFLP data provides inaccurate estimates of true diversity in microbial communities (with the possible exception of TRF-E(var)). We suggest that, where significant differences in T-RFLP diversity indices were found in previous work, these should be reinterpreted as a reflection of differences in community composition rather than a true difference in community diversity.     

Phenology and bathymetric distribution of the profundal chironomid fauna in Starnberger See (F.R. Germany)

Results of the first long-term investigation of the profundal chironomid fauna of Starnberger See, a prealpine lake are reported. Data are presented on the qualitative and quantitative composition of the chironomid fauna in the profundal of Starnberger See, on the spatial variation, and on the phenology of the dominant species, based on pupal occurrence and the seasonal distribution of larval instars. Twenty-five distinct chironomid taxa could be recorded in the profundal zone. Typical inhabitants of the profundal zone of Starnberger See are the larvae of the genus Micropsectra. The maximum abundance of Micropsectra larvae were found at 60 m with 5644 Ind.m⁻². Abundance, distribution and phenology of the dominant chironomid species are discussed in comparison with other lakes.     

Distribution of Chironomidae (Insecta: Diptera) Head Capsules in Recent Sediments of Canadian Arctic Lakes

Thirty-two taxa of chironomid larvae were collected from the sediments of 50 lakes from across the Canadian Arctic Islands. Most chironomid taxa living in the Arctic have wide distributions, with only one taxon, Abiskomyia, showing a clear geographic limitation in this region. Many of these taxa have habitat preferences, among which lake morphometry, pH, nutrients and temperature are important. Due to the complex environmental patterns in the Arctic, lakes in both the northern and southern portion of the Canadian Arctic Archipelago have warmer temperatures and the chironomid assemblages of these two regions resemble each other more than those of the intervening central islands. Chironomid diversity is lowest in the central arctic islands, primarily Devon and Cornwallis Island, where the combination of low nutrients and cold temperatures provide the most severe environment for chironomid survival.     

Diversity as a measure of benthic macroinvertebrate community response to water pollution

The assumption that water pollution causes a depression in the diversity of benthic macroinvertebrates as measured by the Shannon index and similar diversity indices is questioned. An interpretation of the community response of benthic macroinvertebrates to pollution in the Millers River, Massachusetts is developed from species presence-absence and abundance data in conjunction with published information on the species' environmental tolerances as compared to chemical water quality data. This interpretation is compared with one derived solely from diversity index values. The interpretations are quite different; the differences may be attributed to other environmental factors such as impoundments and flow reductions which influence the fauna and thus the diversity index value, but which are not related to pollution. In addition, several intrinsic features of the diversity indices increase their bias.Contribution No. 47 of the Massachusetts Cooperative Fishery Unit jointly supported by the U.S. Bureau of Sport Fisheries and Wildlife, the Massachusetts Division of Fisheries and Game, the Massachusetts Division of Marine Fisheries, and the University of Massachusetts.     

鄱阳湖国家级自然保护区浮游生物群落结构及空间分布

为评价春季大旱后鄱阳湖国家级自然保护区浮游生物现状,对保护区所辖 8 个子湖及赣江和修河部分河段的浮游生物进行调查和分析。调查共发现浮游植物 53 属 97 种、浮游动物 23 属 42 种（包括原生动物 13 种、轮虫 23 种、枝角类 3 种和桡足类 3 种）,其中大湖池和朱市湖是浮游生物种类数最多的 2 个子湖。各子湖及赣江和修河间浮游生物现存量差异较大,其变化范围分别为260（8.18106）cells/L（浮游植物）、363073173 ind./L（浮游动物）,赣江以西区域的子湖和修河的浮游生物现存量显著高于赣江及其以东区域的子湖。调查水域优势度值（Y）大于 0.02 的浮游生物包括蓝藻 1 种、绿藻 2 种、硅藻 5 种、原生动物 4 种及轮虫 5 种。浮游生物 Shannon-Wiener 多样性指数（H'）和均匀度指数（J）的最大值均分别为 2.41 和 0.96,而其丰富度指数（Dm）值均小于 3。3 种多样性指数综合评价表明,保护区各子湖与修河和赣江水体受污染程度较轻,除蚌湖和梅西湖外,均处于中污状态。       

Pelagic food web interactions among benthic invertebrates and trout in mountain lakes

1. Benthic chironomid larvae and the amphipod Gammarus lacustris have been observed in the pelagic habitats of many mountain lakes. The main goal of this study was to determine if chironomid larvae and gammarids potentially affect predator–prey and nutrient dynamics in pelagic food webs of mountain lakes. 2. Eighty‐six mountain lakes were surveyed in Alberta and eastern British Columbia during the years 1965–1984, 1991–2004 and 2005–2007. Pelagic chironomid larvae were found in 86% of these lakes, and pelagic gammarids were found in 29% of lakes. Densities of pelagic chironomid larvae were 92% lower in lakes with pelagic gammarids and 76% lower in lakes with trout (P < 0.05). Intraguild predation of trout on gammarids appeared to reduce predation pressure on chironomid larvae. Gammarids consumed in vitro about 1 chironomid per gammarid per day or about 20% of their body mass in chironomid biomass per day. 3. Concentrations of total dissolved P and N, particulate C, and chlorophyll‐a increased with increasing densities of pelagic gammarids and chironomid larvae in situ (R² = 0.14 ± 0.19 SD, P < 0.1) and in vitro (P < 0.001). 4. Our findings suggest that gammarids and chironomid larvae are linked as predators and prey in pelagic food webs, possibly stimulating phytoplankton abundance via nutrient release.     

Diversity and abundance of littoral cladocerans and copepods in nine Ecuadorian highland lakes

The diversity and abundance of littoral cladocerans and copepods were studied in nine lakes at Reserva Ecológica Cayambe-Coca (Páramo de Guamaní), Ecuador. Six samples were taken in the littoral zone of each lake using a 500 microm mesh plankton conic net. One species of cladocerans (Ephemeroporus acanthoides) is reported for the first time in Ecuador. The diversity (H') and evenness (E) of the lakes were determined and correlated with PCA axes based on their environmental variables. The principal parameters that distinguished these lakes were altitude and pH, an unexpected finding considering that the altitudinal range was very small. Lake size is of secondary importance for this group of lakes. None of the environmental axes correlated with H' or E; nevertheless, a larger than expected species richness was found in a small oligotrophic lake with a high level of DO. Based on our results, we hypothesize that altitude and pH are important factors determining the zooplankton diversity (directly or indirectly) in highland lakes.     

Effects of common carp (<Emphasis Type="Italic">Cyprinus carpio</Emphasis>) and bream (<Emphasis Type="Italic">Abramis brama</Emphasis>) on the structure of the littoral community in a mesotrophic lake (Mesocosm Experiments)

The effect of common carp and bream on hydrochemical parameters, abundance, and structure of phyto-, zooplankton, and macrozoobenthos has been studied in semienclosed mesocosms installed in the littoral zone of a mesotrophic lake. Significant differences in the biomass of different algal groups in mesocosms with fish in respect to the control were established only for diatoms and were not found for other phytoplankton groups. Common carp had a greater effect on the abundance of large zooplankton species (Diaphanosoma brachyurum) compared to bream. The abundance of the small Bosmina longirostris increased in mesocosms both with bream and common carp. The macrozoobenthos biomass reduced at higher rates in mesocosms with common carp than in those with bream, with the strongest effect of common carp on mayfly larvae. The differences between the consumption of chironomid and oligochaete larvae were not established in mesocosms with common carp. Bream mainly affected the larvae of mayflies and oligochaetes and, to a lesser degree, the chironomid larvae.