大型底栖动物生物评价指数比较与应用

采用不同生物指数评价河流健康,结果往往有差异,如何识别各种生物指数的关系和适用性成为亟待解决的问题.基于太子河流域大型底栖动物群落研究,比较了5种大型底栖动物生物指数评价结果的差异.结果表明,5种指数具有极显著的相关性,但由于健康等级划分标准差异,造成不同指数的健康评价等级存在一定差异.同时分析了不同指数对不同类型人为活动影响的敏感性,研究其在河流健康评价中的适用性.结果表明在太子河流域中,BI指数与土地利用类型和溶氧具有较好的相关关系,对这两类的干扰具有较好的指示作用;FBI指数对酸污染和氨氮污染具有较强的指示作用;ASPT指数与耗氧相关的水质指标有较强的负相关;B-IBI指数与总氮呈显著的负相关关系,可较好指示氮污染,而且B-IBI指数与其他类型人为干扰活动均呈显著的相关关系,对土地利用和水质污染也具有较好的指示作用.综上所述,大型底栖动物BI指数和ASPT指数应该分别适用于评价流域土地利用和水化学指标对河流生态系统的影响,而B-IBI可用于评估多种类型人为干扰活动.     

庐山地区底栖大型无脊椎动物耐污值与水质生物学评价

自1996年至1999年，对庐山自然保护区22个采样点的底栖大型无脊椎动物进行了调查．完成了庐山底栖大型无脊椎动物大多数科与部分属的耐污值核定工作，在Hilsenhoff(1988)与Lenat(1993)工作基础上，新增73科的耐污值．首次提出了蜚蠊目B1attodea、脉翅目Neuroptera、半翅目Hemiptera及鞘翅目Coleoptera水生类群的耐污值．其它主要水生昆虫11个目，凡在中国有分布记录或可能在中国及邻近地区有分布的科均收入并提出耐污值．摇蚊科中国常见的16属引用了Lenat(1994)推荐的耐污值，增加了甲壳纲Crustacea、寡毛纲O1igochaeta、腹足纲Gastropoda、腮瓣纲Lemellibranchia、蛭纲Hirudinea、涡虫纲Turbellria与蜱螨纲Acarina水螨总科Hydrachnoidea等的耐污值．利用上述耐污值系统，对22个采样点中的13个进行了连续水质生物监测，对其余9个采样点水质进行了评估．1996年5月至1999年9月期间，13个采样点水质由重污染至极清洁排序可分6类：如琴湖、东谷溪流、电站水库属重污染水体；天桥由轻污染至重污染；2级站、1级站、3级站由很清洁或清洁至一般；芦林湖、电站水库南支流很清洁；黄龙潭由很清洁至轻污染；三叠泉、第四纪冰川遗址、大月山水库为极清洁．多数采样点1996年11月水质好于5月份的水质．1999年所有采样点水质均比1996年2次调查时差，说明庐山水质污染呈加重趋势．图2表2参18     

密云水库上游河流底栖动物群落结构与水质评价

于2013年5月至10月对密云水库上游河流中大型底栖无脊椎动物(以下简称底栖动物)进行了采样调查。结果表明,采集到的底栖动物隶属于4门10纲16目45科,其中以节肢动物种类最多,占总数的80%,且水生昆虫占总数的67%,出现频率最高的是节肢动物门蜉蝣目蜉蝣科的昆虫,出现频率达87%;从分布来看,白河流域采集到的底栖动物种类最多、密度最高,而潮河流域采集到的底栖动物生物量最大;以底栖动物为指示生物的水质评价结果显示,密云水库上游河流中50%采样点的水质为Ⅰ级(清洁),其余50%为Ⅱ级(轻微污染),水质整体较好,与现场生境调查和水质监测的结果相吻合。     

Energy-Based Land Use Predictors of Proximal Factors and Benthic Diatom Composition in Florida Freshwater Marshes

The Landscape Development Intensity index (LDI), which is based on non-renewable energy use and integrates diverse land use activities, was compared to other measures of LU (e.g., %agriculture, %urban) to determine its ability for predicting benthic diatom composition in freshwater marshes of peninsular Florida. In this study, 70 small, isolated herbaceous marshes located along a human disturbance gradient (generally agricultural) throughout peninsular Florida were sampled for benthic diatoms and soil and water physical/chemical parameters (i.e., TP, TKN, pH, specific conductance, etc.). Landscape measures of percent agriculture, percent urban, percent natural, and LDI index values were calculated for a 100 m buffer around each site. The strongest relationships using Mantel's r statistic, which ranges from −1 to 1, were found between benthic diatom composition, the combined soil and water variables, and LDI scores (r=0.51, P<0.0001). Although similar, soil and water variables alone (r=0.45, P<0.0001) or with percent agriculture or percent natural were not as strongly correlated (both Mantel's r=0.46, P<0.0001). Little urban land use was found in the areas surrounding the study wetlands. Diatom data were clustered using flexible beta into 2 groups, and stepwise discriminant analysis identified specific conductance, followed by LDI score, soil pH, water total phosphorus, and ammonia, as cluster-separating variables. The LDI explained slightly more of the variation in species composition than either percent agriculture or percent natural, perhaps because the LDI can combine disparate land uses into a single quantitative value. However, the ecological significance of the difference between land use metrics and diatom composition is controvertible, and additional tests including more varied land uses appear warranted.     

Antioxidant responses to benzo[a]pyrene, tributyltin and their mixture in the spleen of Sebasticus marmoratus

It has been reported that there is an interaction between Benzo[a]pyrene （BaP）, a widespread carcinogenic polycyclic aromatic hydrocarbon, and tributyltin （TBT）, an organometal used as an antifouling biocide. This study was therefore designed to examine the potential in vivo influence of BaP, TBT and their mixture on splenic antioxidant defense systems of Sebastiscus marmoratus. The fish were exposed to water containing environmentally relevant concentrations of BaP, TBT and their mixture. Spleens were collected for biochemical analysis after exposure for 7, 25, 50 d and after recovery for 7, 20 d. Cotreatment with BaP and TBT for 7 d potentiated the induction of glutathione peroxidase （GPx） activity by BaP or TBT alone. The cotreatment for 25 and 50 d resulted in inhibition of GPx activity, which was similar to the effect of TBT. Splenic glutathione S-transferase （GST） activities were significantly elevated in S. marmoratus exposed to BaP starting from 7 d and remained high up to 25 d. However, no further activity change was found with prolonged exposure. Cotreatment of BaP and TBT primarily inhibited the GST activity, which was similar to the effect of TBT. Cotreatment with BaP and TBT for 25 or 50 d potentiated the depletion of GSH （glutathione） by BaP or TBT alone. MDA （malondialdehyde） contents in spleen of S. marmoratus were not significantly altered compared with the control during the test period. Spleen, as an immune organ, is sensitive to exposure of BaP or TBT. It should have an effective mechanism to counteract oxidative damage. Antioxidative defense systems in spleen of S. marmoratus should be considered as potential biomarkers. Short-term exposure of BaP or TBT could result in induction of antioxidant defense system. A significant decrease of these indices, such as GSH, GST, GPx might indicate more severe contamination.     

黄海近岸底栖贝类体内典型有机污染物分布

根据第二次全国海洋污染基线凋查数据,确定黄海近岸底栖贝类体内典型有机污染物的含量、分布及其潜在的生态风险.结果表明,在35%以上的站点,物种体内石油烃含量超过国家海洋生物质量第一类标准(15 000 ng/g),大连湾附近海域贝类体内含量甚至高出第二类标准(50 000 ng/g).在威海、大连湾和胶州湾出现多环芳烃和酞酸酯少数相对高值站点(300 ng/g左右),而其它大多数站点贝类体内多环芳烃和酞酸酯的含量都较低.中、高环组分占优指示近岸海区的多环芳烃主要来源于热解过程;二丁基酞酸酯和2-乙基己基酞酸酯是酞酸酯的主要组分.在所有站点,底栖贝类体内PCBs的含量普遍很低(<10 ng/g).贝类体内DDTs含量超过第一类标准(10 ng/g)的站点大部分集中在南黄海沿岸,海州湾内一站点已超出第二类标准(100 ng/g),而组分以代谢产物DDD和DDE为主.在所有站点的贝类体内都有p,p'-DDT检出,尤其在北黄海的大连湾和蓬莱附近海区(比例高于50%),指示周边地区存在潜在的DDT输入源.据此,大连湾、威海、胶州湾沿岸贝类体内石油烃和多环芳烃含量较高,胶州湾、海州湾附近海域贝类体内DDTs含量较高,这些属于较高生态风险区,而大连湾、蓬莱近岸可能的DDT新输入对底栖环境构成一定威胁.     

Efficacy of extracting indices from large‐scale acoustic recordings to monitor biodiversity

Passive acoustic monitoring could be a powerful way to assess biodiversity across large spatial and temporal scales. However, extracting meaningful information from recordings can be prohibitively time consuming. Acoustic indices (i.e., a mathematical summary of acoustic energy) offer a relatively rapid method for processing acoustic data and are increasingly used to characterize biological communities. We examined the relationship between acoustic indices and the diversity and abundance of biological sounds in recordings. We reviewed the acoustic‐index literature and found that over 60 indices have been applied to a range of objectives with varying success. We used 36 of the most indicative indices to develop a predictive model of the diversity of animal sounds in recordings. Acoustic data were collected at 43 sites in temperate terrestrial and tropical marine habitats across the continental United States. For terrestrial recordings, random‐forest models with a suite of acoustic indices as covariates predicted Shannon diversity, richness, and total number of biological sounds with high accuracy (R² ≥ 0.94, mean squared error [MSE] ≤170.2). Among the indices assessed, roughness, acoustic activity, and acoustic richness contributed most to the predictive ability of models. Performance of index models was negatively affected by insect, weather, and anthropogenic sounds. For marine recordings, random‐forest models poorly predicted Shannon diversity, richness, and total number of biological sounds (R² ≤ 0.40, MSE ≥ 195). Our results suggest that using a combination of relevant acoustic indices in a flexible model can accurately predict the diversity of biological sounds in temperate terrestrial acoustic recordings. Thus, acoustic approaches could be an important contribution to biodiversity monitoring in some habitats.     

上海市青浦区景观格局的粒度效应分析

以上海市青浦区为研究区域，基于ETM遥感影像数据和GIS技术，采用优势规则栅格聚合方法，对分类的ETM数据进行了粒度变换。以景观格局分析程序Fragstats3．3为分析工具，从景观类型水平和景观水平上研究了景观格局的空间粒度效应。研究结果表明：（1）不同的景观类型、不同的景观特征指数对粒度响应存在差异：居住景观和道路景观是对粒度响应最敏感的两种景观类型；形状指数、聚集度指数、斑块数量指数对粒度响应的敏感程度较高，多样性指数、均匀度指数、景观面积比例指数、分维数对粒度响应的敏感程度较低；此外，还发现优势景观随着粒度增加面积增大，形状规则的景观对粒度响应敏感程度低。（2）景观指数的粒度响应曲线存在尺度转折点，且多出现在40、60、80、120m，其中第一尺度区域多为20～40m或20～60m。第一尺度域是选择适宜粒度的较好取值范围，所以本研究中所用景观类型图进行景观指数计算的适宜粒度范围为30-40m。（3）研究发现由不同指数表征相同的生态现象可能会出现相反的粒度效应，在一定程度上体现了景观指数量化景观格局的局限性。     

A SENSITIVITY ANALYSIS OF THE PALMER HYDROLOGIC DROUGHT INDEX1

ABSTRACT: The sensitivity of the Palmer Hydrologic Drought Index to departures from average temperature and precipitation conditions is examined. A time series of zero index values was calculated and then one monthly temperature or precipitation value was perturbed. The resulting time series shows the effects on the index of one anomalous value. Independent series were calculated for temperature anomalies of plus and minus 1, 3, 5, and 10F and for precipitation anomalies of 25, 50, 75, 125, 150, and 200 percent of normal for each calendar month for Colorado, Indiana, Nevada, New York, Oklahoma, South Carolina, South Dakota, Washington, and Wisconsin. Analysis of the time series showed that the period of time required for the index to reflect actual rather than artificial initial conditions could be more than four years. It was also found that the effects of temperature anomalies are insignificant compared to the effects of precipitation anomalies. In some cases, one anomalous precipitation value could result in established wet or dry spells that last for up to two years. Although not examined in detail, the time series suggest that distributions of index values may be asymmetrical and possibly bimodal.     

福州西湖水体富营养化现象分析 Ⅳ、底栖生态与底泥淤积

底泥黑臭，向水面冒气泡是福州西湖水体富营养化现象的一个突出表现。目前，有关管理部门主要靠定期挖泥清淤来控制底泥富营养状况。然而１９９９年秋季福州西湖底栖动物种类和数量调查结果却显示，由于底栖动物贫乏，西湖底泥富营养化问题将由于生态失调而进一步深化。建议将控制入湖泥沙量、减少挖泥频度、恢复底栖生态作为一项治淤措施予以考虑。