UK37沉积地层记录:三门湾海表温度(SST)和EI Ni(n)o现象及其对大型底栖动物生命活动的影响

应用U^K37估算三门湾（1916～2003年）表层海水温度,SST波动范围在15．97～18．00℃之间,年平均为17．03℃,此计算值比当年实测海水全年平均温度低3．52℃,与秋季海水实测温度相接近。研究显示出,三门湾的EINino事件在大尺度上与东太平洋一样,均受制于气候影响因素,但在变化尺度上又受到地理位置和地方性气候（季风）的影响,事件在形式和年代上相互对应,但其颤动幅度远不如东太平洋强烈。同时通过比较EINino期间（2003／2002）和非EINino期间（2006／2005）大型底栖生物的群落结构变动信号、生物量、栖息密度以及物种多样性等,研究显示出三门湾若干大型底栖生物对EINino事件产生响应迹象,若干大型底栖生物对EINino的响应主要是通过海洋环流的影响来体现生命和生态效应的,主要表现在改变了底栖生物种类数和多样性、以及生命活动及栖息密度分布模式。在EINino影响下,台湾暖流人侵势力加强,2003／2002年底栖生物群落种类数减少与海流人侵及盐度密切相关;通过与同海域浮游动物对比研究,三门湾海域浮游动物和底栖生物对EINino的生态响应均较大,前者可能与三门湾海域水域较浅,外海暖水从底部人侵改变水温和盐度,直接影响底栖生物的生态环境,致使种类数大大减少有关;而后者由于人侵暖水强度增大,携带大量暖水性浮游动物,呈现出在EINino时期浮游动物种类数、生物量和丰度有偏高趋势。     

UK37沉积地层记录：三门湾海表温度(SST)和EI Niño现象及其对大型底栖动物生命活动的影响

应用U K37估算三门湾（1916～2003年）表层海水温度,SST波动范围在15.97～18.00℃之间,年平均为17.03℃,此计算值比当年实测海水全年平均温度低3.52℃,与秋季海水实测温度相接近。研究显示出,三门湾的EI Nio事件在大尺度上与东太平洋一样,均受制于气候影响因素,但在变化尺度上又受到地理位置和地方性气候(季风)的影响,事件在形式和年代上相互对应,但其颤动幅度远不如东太平洋强烈。同时通过比较EI Nio期间（2003/2002）和非EI Nio期间（2006/2005）大型底栖生物的群落结构变动信号、生物量、栖息密度以及物种多样性等,研究显示出三门湾若干大型底栖生物对EI Nio事件产生响应迹象,若干大型底栖生物对EI Nio的响应主要是通过海洋环流的影响来体现生命和生态效应的,主要表现在改变了底栖生物种类数和多样性、以及生命活动及栖息密度分布模式。在EI Nio影响下,台湾暖流入侵势力加强,2003/2002年底栖生物群落种类数减少与海流入侵及盐度密切相关;通过与同海域浮游动物对比研究,三门湾海域浮游动物和底栖生物对EI Nio的生态响应均较大,前者可能与三门湾海域水域较浅,外海暖水从底部入侵改变水温和盐度,直接影响底栖生物的生态环境,致使种类数大大减少有关;而后者由于入侵暖水强度增大,携带大量暖水性浮游动物,呈现出在EI Nio时期浮游动物种类数、生物量和丰度有偏高趋势。     

三门湾健跳港网箱养殖区浮游生物多样性的夏季调查

调查了三门湾健跳港海水养殖区夏季浮游生物的种类组成、密度和多样性指数,并将浮游生物群落指标与水质理化因子进行相关分析。共发现浮游生物29种,其中浮游植物14种,第一优势种为中勒骨条藻(Skeletonema costatum);浮游动物15种,第一优势种为太平洋纺锤水蚤(Acartia pacifica)。表层浮游植物的平均密度为43 328ind·L^-1,Shannon-Weiner多样性指数为0.826;浮游动物平均密度为389ind.m^-3,Shannon-Weiner多样性指数为2.964。相关分析结果表明:无机氮、无机磷促使了浮游植物大量繁殖,并使浮游动物多样性指数提高。网箱养鱼区水体富营养化指数与浮游植物多样性指数之间有一定的正相关关系,与浮游动物多样性指数之间呈显著的正相关关系。     

淀山湖浮游动物的群落结构及动态

为帮助利用生物操纵技术进行淀山湖水体富营养化治理,2004年1月至2005年12月对淀山湖浮游动物群落结构,包括种类组成、种群动态、现存量进行了2周年的系统调查.淀山湖浮游动物有128种,其中浮游原生动物23属29种、轮虫23属51种、枝角类15属33种、桡足类15种.年均密度6 965ind/L,原生动物和轮虫分别占62.19%和36.77%,密度高峰出现在春季;生物量年均为6.00mg/L,以轮虫和枝角类占优势,分别占51.65%和38.38%,生物量高峰出现在夏季.4个类群浮游动物多样性指数H'与其均匀度指数J呈显著正相关,原生动物群落多样性指数H'与其密度呈显著负相关.根据浮游动物密度及优势种组成特征判断,淀山湖水质为富营养型.原生动物多样性指数具有较好的水质指示作用.     

钦州湾大型底栖动物生态学研究

通过2008年~2009年在钦州湾及附近海域进行的4个航次的大型底栖动物调查,共获大型底栖动物8门62科94种,软体类最多,其次为多毛类,种类季节变化较大。以优势度指数Y>0.02为判别标准,调查区春季优势种为方格皱纹蛤（Periglypta lacerata (Hanley)）、刺足掘沙蟹（Scalopidia spinosipes Stimpsom）和独齿围沙蚕（Perinereis cultrifera Grube）,夏季优势种为方格皱纹蛤、刺足掘沙蟹和持真节虫,秋季优势种为曲波皱纹蛤和网纹藤壶,冬季优势种为肋鲳螺和方格皱纹蛤。春、夏季优势种变化不大,秋、冬季优势种变化较大,除方格皱纹蛤外均为季节特有种。海区底栖生物平均总密度和平均总生物量分别为439ind./m2和115.14g/m2。与20世纪80年代钦州湾茅尾海调查结果相比,平均栖息密度有所升高,但是平均生物量却有较大程度的降低。底栖动物群落的丰富度指数（D）、Shannon-Wiener多样性指数（H′）和均匀度指数（J′）平均值分别为4.01、1.80和0.73,水平不高。用SPSS软件将各站大型底栖动物的平均密度、平均生物量、多样性指数等生态特征值与水深等理化因子进行了Pearson相关分析,结果表明春季各特征指数与环境因子相关性不显著;夏季丰度、多样性指数和均匀度指数均与水深呈显著负相关,种类数、丰富度和多样性指数与沉积物pH呈显著负相关;秋季密度与硫化物呈显著正相关;冬季生物量与硫化物和有机质均呈显著正相关。     

鲢放养和施肥对盐碱池塘围隔生态系统浮游生物群落的影响

报道了单养链（Hypophthalmichthys molitrix)和施肥对盐碱池塘围隔生态系统浮游生物群落的影响,链的放养使浮游植物丰度,叶绿素a 含量和和初组生产力增大,浮游植物小型化,生物量以小型硅藻和绿藻占优势,裸藻和金藻占有相当比重;浮游动物生物量减少,特别是枝角类的生物量无鱼围隔大于有鱼围隔,且多是较大型的种类,施肥特别是施无机肥能显著地提高浮游植物丰度和初级生产力,浮游动物生物量也增大,施有机肥围隔浮游植物和浮游动物生物量虽高于有鱼对照围隔,但其浮游植物初级生产力,叶绿素a含量,浮游生物多样性指数,P／R系数均较低,链鱼的生长最差,文中讨论了滤食性鱼类和施肥对浮游生物的影响。     

UK~(37)沉积地层记录:三门湾海表温度(SST)和EI Nio现象及其对大型底栖动物生命活动的影响

应用UK37估算三门湾(1916~2003年)表层海水温度,SST波动范围在15.97~18.00℃之间,年平均为17.03℃,此计算值比当年实测海水全年平均温度低3.52℃,与秋季海水实测温度相接近。研究显示出,三门湾的EI Nio事件在大尺度上与东太平洋一样,均受制于气候影响因素,但在变化尺度上又受到地理位置和地方性气候(季风)的影响,事件在形式和年代上相互对应,但其颤动幅度远不如东太平洋强烈。同时通过比较EI Nio期间(2003/2002)和非EI Nio期间(2006/2005)大型底栖生物的群落结构变动信号、生物量、栖息密度以及物种多样性等,研究显示出三门湾若干大型底栖生物对EI Nio事件产生响应迹象,若干大型底栖生物对EI Ni o的响应主要是通过海洋环流的影响来体现生命和生态效应的,主要表现在改变了底栖生物种类数和多样性、以及生命活动及栖息密度分布模式。在EI Nio影响下,台湾暖流入侵势力加强,2003/2002年底栖生物群落种类数减少与海流入侵及盐度密切相关;通过与同海域浮游动物对比研究,三门湾海域浮游动物和底栖生物对EI Nio的生态响应均较大,前者可能与三门湾海域水域较浅,外海暖水从底部入侵改变水温和盐度,直接影响底栖生物的生态环境,致使种类数大大减少有关;而后者由于入侵暖水强度增大,携带大量暖水性浮游动物,呈现出在EI Nio时期浮游动物种类数、生物量和丰度有偏高趋势。     

稻鱼共作生态系统浮游植物群落结构和生物多样性

稻鱼共作技术是中国传统农业的精华,通过对稻鱼共作系统水体浮游植物的种类组成、密度、生物量及多样性进行分析,明确该系统中浮游植物数量变化特性,为进一步开发利用这一经典农艺提供理论基础和实践依据。结果表明,稻田生态系统中浮游植物群落包含蓝藻门、甲藻门、隐藻门、裸藻门、绿藻门和硅藻门等6门,共38属93种。稻鱼共作显著增加稻田水体浮游植物的密度和生物量,降低硅藻和蓝藻的优势度,增加绿藻和裸藻的优势度,提高了稻田水体浮游植物多样性指数。     

罗非鱼对盐碱池塘围隔浮游生物群落的影响

本文报道了单养尼罗罗非鱼 (Orecohromisniloticus)对施肥处理下盐碱池塘围隔生态系统浮游生物群落的影响。结果表明 ,罗非鱼的放养使浮游植物丰度、叶绿素a含量和初级生产力增大 ,浮游植物小型化 ,生物量以小型硅藻和绿藻占优势 ,裸藻占有相当比重 ;浮游动物生物量也增大 ,桡足类占优势 ,枝角类小型化 ,原生动物密度增大。施肥特别是施有机肥能显著地提高浮游植物生物量 ,使透明度降低 ,但施无机肥对初级生产力和浮游动物生物量影响不大。施有机肥围隔浮游植物和浮游动物密度、浮游动物生物量和浮游生物多样性指数高于其他有鱼围隔 ,罗非鱼的生长最好。文后讨论了罗非鱼滤食和施肥对浮游生物群落结构的影响 ,并与鲢鱼的实验结果 (赵文 ,1999)进行了比较     

长江口潮间带底栖生物生态及变化趋势

基于长江口3个区域潮间带(崇明东滩、南汇边滩和嵊山岛)监测数据,对长江口区域潮间带底栖生物生态现状及变化趋势进行评价。结果表明,2019年长江口海域泥相和岩相潮间带共鉴定大型底栖生物9门57种,软体动物、甲壳类和多毛类构成主要类群。崇明东滩、南汇边滩两个泥相潮间带底栖生物平均栖息密度分别为96.4个/m~2和160.4个/m~2,平均生物量分别为68.42 g/m~2和45.71 g/m~2;嵊山岛岩相潮间带平均栖息密度和生物量分别为488.9个/m~2和763.72 g/m~2。各断面多样性、丰富度和均匀度指数分别位于1.36—3.24、0.75—2.88和0.48—0.77,泥相潮间带低潮区生物多样性优于中潮区和高潮区,岩相潮间带中潮区生物多样性最好。聚类分析可见长江口海域潮间带底栖生物分为泥相和岩相2个大组群,物种分布存在明显的分潮区现象,高潮区站位成群或与个别中潮区站位成群,低潮区站位成群或与个别中潮区站位成群,表明底质类型和潮汐是影响潮间带大型底栖生物群落结构的主要因子。近30年来,崇明东滩和南汇边滩底栖生物种类数存在一定波动,嵊山后陀湾断面生物种类数明显下降;3个区域潮间带...     

Cyanobacteria dominance influences resource use efficiency and community turnover in phytoplankton and zooplankton communities

Freshwater biodiversity loss potentially disrupts ecosystem services related to water quality and may negatively impact ecosystem functioning and temporal community turnover. We analysed a data set containing phytoplankton and zooplankton community data from 131 lakes through 9 years in an agricultural region to test predictions that plankton communities with low biodiversity are less efficient in their use of limiting resources and display greater community turnover (measured as community dissimilarity). Phytoplankton resource use efficiency (RUE = biomass per unit resource) was negatively related to phytoplankton evenness (measured as Pielou's evenness), whereas zooplankton RUE was positively related to phytoplankton evenness. Phytoplankton and zooplankton RUE were high and low, respectively, when Cyanobacteria, especially Microcystis sp., dominated. Phytoplankton communities displayed slower community turnover rates when dominated by few genera. Our findings, which counter findings of many terrestrial studies, suggest that Cyanobacteria dominance may play important roles in ecosystem functioning and community turnover in nutrient‐enriched lakes.     

Structural characteristics of phytoplankton assemblages in tidal and non-tidal freshwater systems: a case study from the Schelde basin, Belgium

1. The Schelde estuary, its side basins and their tributaries were sampled in August 1995 and April 1996 for phytoplankton abundance, biomass, diversity and species composition. In order to clarify the underlying causes of differences in phytoplankton communities, the results were related to some important abiotic variables.
2. Although species richness and diversity did not differ significantly between the riverine and the freshwater tidal stations, multivariate ordination techniques based on species abundances differentiate between these two ecosystems. While in the rivers phytoplankton standing stocks were as high in summer as in spring, standing stocks in the freshwater tidal estuary were significantly higher in the August samples.
3. It is postulated that due to the resuspension of suspended solids by estuarine currents, light is limiting phytoplankton development in the freshwater tidal reaches in spring. At that stage, phytoplankton populations have already developed in the rivers. In summer, zooplankton prevent any further increase of riverine phytoplankton populations. In the freshwater tidal estuary, however, increased light levels, a higher residence time compared to rivers and the absence of zooplankton due to low oxygen concentrations permit phytoplankton populations to bloom.     

大亚湾石化排污海域生态系统健康评价

基于近海生态系统健康评价模型,以2011—2012年间海洋生态环境调查数据为基础,对大亚湾石化排污海域的生态系统健康状态进行了综合评价。结果表明:丰水期(2011年8月),大亚湾石化排污海域生态系统健康综合指数为0.808,健康状态为"好",空间分布为近岸海域健康状况好于远岸海域,其中底栖生物多样性综合指数是影响该海域生态系统健康的主要负面因子。枯水期(2012年1月),石化排污海域生态系统健康综合指数为0.767,健康状态为"一般",远岸海域健康状况好于近岸海域,浮游植物多样性综合指数和底栖生物多样性综合指数是影响该海域生态系统健康的主要负面因子。与2006—2007年相比,大亚湾石化排污海域生态系统的健康状况正向"一般"状态退化。     

Ecosystem Functions across Trophic Levels Are Linked to Functional and Phylogenetic Diversity

In experimental systems, it has been shown that biodiversity indices based on traits or phylogeny can outperform species richness as predictors of plant ecosystem function. However, it is unclear whether this pattern extends to the function of food webs in natural ecosystems. Here we tested whether zooplankton functional and phylogenetic diversity explains the functioning of 23 natural pond communities. We used two measures of ecosystem function: (1) zooplankton community biomass and (2) phytoplankton abundance (Chl a). We tested for diversity-ecosystem function relationships within and across trophic levels. We found a strong correlation between zooplankton diversity and ecosystem function, whereas local environmental conditions were less important. Further, the positive diversity-ecosystem function relationships were more pronounced for measures of functional and phylogenetic diversity than for species richness. Zooplankton and phytoplankton biomass were best predicted by different indices, suggesting that the two functions are dependent upon different aspects of diversity. Zooplankton community biomass was best predicted by zooplankton trait-based functional richness, while phytoplankton abundance was best predicted by zooplankton phylogenetic diversity. Our results suggest that the positive relationship between diversity and ecosystem function can extend across trophic levels in natural environments, and that greater insight into variation in ecosystem function can be gained by combining functional and phylogenetic diversity measures.     

富营养化水体生物净化效应的研究进展

水体富营养化治理已成为当今世界性难题,解决水体富营养化问题的关键是调控水生生态系统结构,使其恢复自然、健康和稳定的水生生态系统功能,提高水生生态系统的生物净化能力,水生高等植物及水生植被是水生生态系统中最重要的初级生产者,它们个体大、生长周期长、吸取和储存营养物质的能力强,保持和恢复一定数量的水生植物种群可抑制浮游植物的生长,提高系统的生物多样性,使水生生态系统结构更加稳定,水生动物在水生生态系统物质和能量循环中处于十分重要的地位,浮游动物和底栖动物可直接捕食浮游植物,控制浮游植物的数量;而改变鱼类种群结构可提高浮游动物的生物量,从而间接控制浮游植物的大量繁殖,达到治理水体富营养化的目的,我国的生物净化研究还处于起步阶段,今后在水生高等植物及水生植被生物净化的关键技术及优化水产养殖新模式技术研究方面有待提高,这将对我国水体富营养化治理及水体可持续利用有着重要的意义。     

Littoral species diversity and biomass: concordance among organismal groups and the effects of environmental variables

Biomass and species diversity (richness and evenness) of littoral organisms were explored in 27 sites in three basins of the large Lake Saimaa system in eastern Finland. The basins differed in degree of nutrient loading and trophic status. Six organismal groups, i.e., phytoplankton, periphyton, macrophytes, crustacean zooplankton, benthic macroinvertebrates and fish were studied. Factors affecting the biomass and diversity of these groups were explored by multiple stepwise regression analysis. The biomass of different groups was explained by the same variables, mainly nutrients, while diversity was associated with different environmental factors among the studied groups. The biomass of periphyton, phytoplankton, zooplankton, and fish correlated significantly with each other. There was also an apparent association between the biomass of macrophytes and that of benthic invertebrates. However, no significant correlations were found among the diversity of the studied groups. In accordance with previous studies, our results did not support the existence of species-rich hotspots or the possibility of using any surrogate taxon to reveal overall biodiversity. Thus, for conservation planning, biological surveys should include extensive collection of taxonomic groups and organisms at all trophic levels.     

Temporal variations and pond age effect on plankton communities in semi-intensive freshwater marron (Cherax cainii,Austin and Ryan, 2002) earthen aquaculture ponds in Western Australia

The abundance and diversity of the plankton community represents the health of the aquatic ecosystem, and plays an important role in the growth of cultured animals under aquaculture conditions. The temporal variations of plankton abundance, taxonomic composition, diversity, evenness and species richness were studied in three old and three new semi-intensive marron (Cherax cainii, Austin and Ryan, 2002) ponds. Water parameters such as temperature, dissolved oxygen, pH, turbidity, TAN, nitrite, nitrate and reactive phosphate were recorded, and plankton samples were collected every two months, for one year of juvenile production cycle. A total of twenty-six phytoplankton and seven zooplankton genera were recorded. Chlorophyceae was the dominant class of phytoplankton throughout the year, followed by Trebouxiophyceae. Rotifera comprised 49.8% of the total zooplankton community (individuals L^?1), the largest proportion of any group. Temporal variations impacted the plankton abundance and community structure, and plankton abundance were more abundant during summer. The pond age did not influence the phytoplankton abundance, whereas zooplankton abundance was higher in older ponds.     

Spatial and temporal variations reveal the response of zooplankton to cyanobacteria

The effects of cyanobacteria on zooplankton abundance, structure and diversity were investigated, based on a systematic study on spatial and temporal variations of cyanobacteria and zooplankton in Lake Taihu from 1998 to 2007. It was found that similar increasing trends of cyanobacteria/phytoplankton ratios were accompanied by different trends in biomass, composition and biodiversity of zooplankton in different regions of the lake; the cladocerans benefitted from the increase in cyanobacteria; however, rotifers and protozoans were negatively affected by cyanobacteria. The biomass-based biodiversity of phytoplankton and zooplankton was negatively affected by cyanobacteria as well, and the adverse effects were in proportion to the cyanobacteria/phytoplankton ratio. These results indicated interestingly that higher amounts of cyanobacteria do not necessarily reduce zooplankton biomass, as the biomass of larger zooplankton such as cladocerans was positively related to cyanobacteria. The findings are essential to understand the complex ecological effects of cyanobacteria blooms in lakes.     

Species richness vs evenness: independent relationship and different responses to edaphic factors

The main components of species diversity are richness and evenness. Species richness has been the subject of biodiversity studies more often than species evenness. Some simulated models suggest that the relationship between these two components is equal and predictable in a stable environment. This study was conducted in a human-shaped and unstable environment in arable field boundaries. A total of 30 sampling plots were laid out at random in the boundaries. Vegetation at the sites was of meadow type. The relationship between species richness and evenness, and their responses to edaphic nutrient factors in the field boundaries, were examined by correlation analysis and an ordination method. Correlation analyses demonstrated that no consistent pattern was present in the relationship between species evenness and species richness in this human-shaped ecosystem. Species richness and evenness also had different responses to edaphic factors, with species richness being negatively correlated with phosphorus, and species evenness negatively correlated with the ratio of organic carbon to total nitrogen in soil. The results indicate that different and independent ecological processes determine species richness and evenness. The relationship between these two components may be site-specific, reflecting variation in resource utilization by plant species. The pattern thus reflects the spatial heterogeneity of disturbances or 'patchiness' of resources between sites in a semi-natural ecosystem.     

Resource stoichiometry and consumers control the biodiversity-productivity relationship in pelagic metacommunities

Recent theory suggests that both biodiversity and productivity are constrained by resource supply rates and ratios and that resource stoichiometry is the key to understanding the relationship between biodiversity and productivity. We experimentally tested this theory using pelagic metacommunities. We amended existing predictions by explicitly considering evenness as an aspect of biodiversity and including control of algal biomass by consumption in addition to competition. The metacommunities received a different phosphorus (P) supply and the three patches within each metacommunity differed in their nitrogen (N) supply, which created different N∶P ratios (2, 16, and 128). All patches were inoculated with a phytoplankton assemblage consisting of five species, and half of the metacommunities received two ciliate species as consumers. At the level of the entire metacommunity, algal biomass increased with increasing P supply, whereas species richness and evenness decreased with increasing P supply. Without consumers, resource use efficiency (RUE; realized biomass per unit of P) increased with increasing richness and evenness. Consumer presence reduced overall biomass and richness and precluded a correlation between RUE and biodiversity. At the patch level, local evenness correlated with higher RUE at both imbalanced N∶P ratios (2 and 128) but not at a balanced N∶P ratio. In conclusion, overall P supply constrained realized biomass and altered diversity, whereas resource stoichiometry shaped the relationship between biodiversity and RUE.