秦岭南坡陕西洋县辖区哺乳动物物种多样性的空间分布格局

物种多样性的空间分布格局一直是生态学和生物地理学研究的一个热点问题。山地生态系统的生境异质性和物种多样性高, 适合研究物种多样性空间分布格局及其相关机制。2016年11月至2017年11月, 本研究选取秦岭南坡陕西洋县辖区作为研究区域, 采用样线法、红外相机法和笼捕/夹捕法, 系统分析了8目21科48种哺乳动物物种多样性的空间分布格局。研究结果发现秦岭南坡洋县辖区哺乳动物物种丰富度的空间分布格局大致是中南部低, 北部和东部高; 物种多样性指数大致是中南部和北部低, 东部高。啮齿类动物和非啮齿类动物的空间分布格局存在差异。哺乳动物物种丰富度和多样性指数的垂直分布格局都符合中峰模式, 但啮齿类动物和非啮齿类动物间存在差异。最优线性模型结果表明, 研究地区哺乳动物物种多样性的空间分布格局受到多种环境因素的共同影响。其中, 年均温与物种多样性的相关性最强, 在6个最优线性模型中贡献都是最大。综上, 秦岭南坡洋县辖区中高海拔区域的物种多样性较高, 应加强对中高海拔地区的保护, 以维系该区域较高的生物多样性。     

中国典型森林生态系统乔木层群落物种多样性的空间分布格局及其影响因素

物种多样性地理分布格局及其成因是生物地理学和宏观生态学研究的核心问题之一,基于中国13个典型森林生态系统乔木层群落植物的调查数据,分析物种多样性随经纬度的变化规律,探讨物种多样性空间分布格局的影响因素。结果表明:(1) 13个典型森林生态系统的4个物种多样性指数均随经纬度上升而下降,其中物种丰富度变化更为显著,而Shannon-Wiener指数、Simpson指数和Pielou指数随经度上升变化不显著;(2)相关性分析结果显示,物种多样性指数与植物特性、能量和水分因子的单因素相关关系并不一致。其中,物种丰富度、Shannon-Wiener指数和Simpson指数与年均温、最冷月均温、温度年较差和潜在蒸散量的相关性最显著(P0.01),Pielou指数与年均温、最冷月均温、实际蒸散量、潜在蒸散量和郁闭度有显著相关关系(P0.05);(3)方差分解结果表明,能量和水分的共同作用对物种多样性指数空间分布格局的解释率最高,达到15%—42%;植物特性、能量和水分因子三者共同作用对物种多样性指数空间分布格局解释率次之,为14%—27%;植物特性与能量因子或水分因子两者之间的共同作用以及植物特性和水分因子独立作用对物种多样性指数空间分布格局的解释率较小,其中能量因子对物种多样性指数空间分布格局的单独解释率高于植物特性或水分因子。研究表明能量和水分共同作用是影响大尺度森林乔木层物种多样性空间分布格局形成的主要因素,但植物特性的差异对物种多样性空间分布格局影响也不可忽视。     

基于耦合模型和遥感技术的江苏中部海岸带生态系统健康评价

以生态系统健康理论为基础,从资源环境、景观生态、人类活动3个方面,按活力、组织力和恢复力3个子系统选取了10个代表性指标,构建了遥感技术支持下的海岸带陆域生态系统健康评价指标体系,并耦合TOPSIS模型和VOR生态系统健康度量模型对江苏中部海岸新洋港至川东港岸段进行了应用评价。研究结果表明:江苏中部海岸生态系统健康状态处于健康和良好的区域占27.62%,一般占60.94%,较差和差占11.44%,整体生态健康状况中等偏好。从地物类型和空间分布来看,斗龙港至四卯酉河岸段以滩涂植被、农田和围海养殖区为主,植被和水体对气候调节有积极作用,整体生态健康状况良好;四卯酉河至王港岸段由于大丰港建设,港区陆域植被覆盖率低、热岛效应强,建筑将原本连通的自然景观隔断,导致斑块数量增多,斑块面积减小,加剧了景观破碎化,对原有海岸带生态系统产生一定的破坏,生态健康状况相对较差;此外,新洋港至斗龙港岸段以及川东港岸段以自然保护区湿地为主,植被覆盖度高,人为干扰程度小,生态健康状况也较好。由于该耦合模型评价方法直接基于遥感监测数据,且无需赋予指标权重,因此研究结果相对更加客观,更能反映海岸带生态系统的实际健康状况。     

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.     

京津冀地区生态系统健康评估及时空变化

结合生态系统健康和景观生态学理论, 基于“压力—状态—响应(PSR)”模型构建了京津冀地区生态系统健康评价指标体系, 综合层次分析法和熵权法得到指标权重值。首先模拟了京津冀地区2000年和2015年的生境质量、固碳、水质净化、产水量、土壤保持等生态系统服务功能, 进而评价了京津冀地区2000年和2015年栅格尺度的生态系统健康空间分布和时空变化。研究结果显示: 1)生境质量、固碳功能和水土保持功能的高值主要分布在该区域北部和西部的山地区域, 而低值则主要分布在中部和东南部区域。水质净化功能主要分布在南部, 而产水量功能主要分布在沿海地区。2)京津冀地区生态系统压力主要分布在北京、天津的市区等地。时间上北部压力变化最小, 中部的北京、天津等地增加最大, 西部地区增加较小。3)状态最差的区域是各个地市的城区以及沿海地区, 而最好的地区分布在北部和西部等地的山区。时间上北部地区增加明显, 而南部有明显的降低趋势, 表现出从北向南变差的趋势。4)京津冀地区响应最好的是西部和北部的山地和天津、北京等地, 说明人类社会对于生态系统保护的意识较好。时间上, 南部和北部地区响应增加明显, 而中部的北京、天津等地增加较小。5)生态系统一般健康的区域占绝大多数, 主要分布在京津冀的中部、南部和西北部。良好地区主要分布在该区域的北部和西部的林地区域。时间上, 健康程度变化最大的在该区域的南部和北部, 而增加较小的地区分布在北京、天津周边。     

天山北部拟南芥生存群落物种多样性的空间格局

在对新疆天山北部浅山地带拟南芥（Arabidopsis thaliana）生存分布调查的基础上,研究了13个拟南芥样地（生存群落）的综合物种多样性格局特征及环境因子对其空间格局的影响。结果表明,各样地物种多样性指数差异明显。天山西支婆罗科努山的伊犁地区多样性最大,塔尔巴哈台山额敏地区其次,天山中部8个样地多样性较低且变幅较大,阿尔泰山阿勒泰地区多样性指数处于中等水平,总体上,13个拟南芥样地物种多样性空间格局异质性明显;各样地拟南芥及其邻近种种类及数量不一,以天山中部最多;物种多样性空间格局与降水量变化关系拟合较好,随降水量增加而增大;物种多样性指数的DCCA排序表明,除降水量外,坡向、有效钾及电导率等微环境因子也是影响物种多样性空间格局的重要因素。     

火干扰对大兴安岭北部原始林下层植物多样性的影响

在景观尺度自然火干扰历史研究的基础上,采用1个物种丰富度指数（物种数 S）、2个均匀度指数（Pielou均匀度指数Eh＇和Alatalo均匀度指数E）、3个物种多样性指数（Shannon-Wiener指数H＇,Hill多样性指数N1和N2）共6个？多样性指数,研究了长期火干扰与最近一次火干扰对大兴安岭北部原始林下木层、草本层及下层总体的植物多样性的影响.研究结果表明,本区下层植物的物种数、均匀度指数和多样性指数都以下木层显著大于草本层,因而下木层对下层植物总体生物多样性的贡献最大,也是主要影响因子.火干扰对下木层、草本层和下层总体的物种丰富度和物种多样性有显著影响,而对均匀度的影响不显著.长期的火干扰影响下,下木层、草本层和下层总体的物种数、各类均匀度指数和物种多样性指数都呈现如下格局：高频类＞中频类＞低频类,低强类＞中强类＞高强类.最近一次火干扰影响下,各个生物多样性指数都表现为一致的趋势：低强类＞中强类＞高强类;短期类＞长期类＞中期类.下层植物多样性与火干扰的关系是长期适应的结果.     

溧阳地区森林景观的生物多样性评价

对在江苏省南部和太湖流域具有一定代表性的溧阳地区的森林景观开展了森林生态系统多样性的研究,对主要森林生态系统类型分层次进行了植物种多样性的调查分析,基于生态系统和物种两个水平的多样性调查, 以W和Z两个指标对研究区域森林景观的生物多样性特征进行历史的动态评价,结果体现出在近20a的森林经营过程中,溧阳地区森林景观的生物多样性水平有下降的趋势。／     

厦门市重点保护植物空间优先保护格局研究

生物多样性保护对维持城市生态系统功能具有重要意义。以39种厦门市重点保护植物为对象,通过物种分布模型MaxENT获得物种潜在分布栅格图,利用空间保护优先化定量工具Zonation软件识别理论上既适宜重点保护植物生存又能够保证景观连通性的区域,获得本地重点保护植物景观保护等级。根据2020年全球生物多样性目标,将景观保护等级最高的17%区域视为多物种空间优先保护区,结合Zonation模型生成的随景观丧失物种加权灭绝风险曲线,将保护等级最高的8%区域划为一级保护区,保护等级在8%-17%范围内的区域划为二级保护区。利用MaxENT模型中的jackknife刀切法发现海拔是对本地重点保护植物分布影响最大的环境因子,优先保护区集中分布于海拔较低的海岸带区域。将优先保护区与自然保护地建设现状、厦门市生态功能区规划、土地利用规划、城市总体规划对比发现厦门市岛外西部、北部的优先保护区得到了较好保护;岛外的西南部及东南部、岛内的东部及南部海岸带的优先保护区被建设用地大规模占用,已纳入自然保护地范围的区域较少,存在大量的海岸带优先保护区保护空缺;岛外东南部的部分优先保护区虽未被占用,但规划中属发展备用地,缺乏生态保护。为避免优先保护区面积的进一步萎缩,应重点关注海岸带区域优先保护区的生态保护,将目前属于发展备用地的优先保护区转划为生态留白空间,针对一级、二级优先保护区分别实施刚性和弹性的生态保育措施,在保护生物多样性的同时,严控对海岸带区域优先保护区的进一步开发利用,协调优先保护区内保护与开发利用间的关系。     

大兴安岭北部次生林演替过程中物种多样性的变化及其影响因子

物种多样性是生物多样性的重要组成部分。森林演替过程中物种多样性的变化会直接影响生态系统功能和稳定性。因此,揭示森林演替过程中物种多样性变化及其与影响因子之间的关系,对于准确预测森林生态过程和生物多样性格局具有重要意义。该研究选择大兴安岭北部白桦(Betula platyphylla)林(演替前期)、白桦-兴安落叶松(Larix gmelinii)混交林(演替中期)和兴安落叶松林(演替后期)为研究对象,采用空间代替时间的研究方法,分析我国寒温带地区森林演替过程中物种多样性的变化规律及其与影响因子之间的关系。结果表明:(1)大兴安岭北部森林演替过程中物种丰富度和多样性呈显著增加趋势,演替初期Margalef丰富度指数和Shannon-Wiener多样性指数分别为2.42和2.69,演替末期则分别为5.90和3.43;而物种Pielou均匀度指数无显著差异。(2)随森林演替的进行,植物群落的相似性逐渐降低,差异性逐渐增强,Jaccard指数、Sorenson指数和Bray-Curtis指数均减小。(3)森林演替过程中土壤pH、有机质含量、全氮含量和全磷含量对物种多样性存在显著影响,其中全氮含...     

长江口浮游甲壳动物空间分布特征

2010年研究了长江口南、北支浮游甲壳动物的空间分布特征。共采集到浮游甲壳动物50种,其中桡足类39种,枝角类11种。种类数南支高于北支;平均密度北支高于南支,南、北支分别为1.7 ind./L和61.8 ind./L。基于群落相似性矩阵的CLUSTER聚类和MDS分析显示,在群落相似性为40%时,长江口区域浮游甲壳动物群落可分为北支组、南支组1和南支组2共3组。3组的优势种有差异。浮游甲壳动物的平均密度变化趋势为北支组（61.8±22.11 ind./L）〉南支组1（3.07±2.06 ind./L）〉南支组2（0.72±0.45 ind./L）。盐度、潮汐和径流量是影响长江口南北支浮游甲壳动物种类组成、密度和空间分布差异的重要环境因素。     

Application of specific exergy to macrophytes as an integrated index of environmental quality for coastal lagoons

This work aims to explore the application of specific exergy on macrophytes as an integrated index to assess ecosystem health in coastal lagoons, and to analyse its possible application in view of the implementation of the Water Framework Directive of the European Union (European Commission, 2000). Exergy and specific exergy are calculated as a function of the biomass multiplied by a weighting factor (β), which express the quantity of information embedded in the biomass. Until now only few general values of β have been published. Therefore, we have extended the calculation of β-values for 244 seaweed and seagrass species which are common in Mediterranean coastal lagoons. The estimated β-values have been then compared with macrophyte-based indicators which have been recently developed, namely the Ecological Evaluation Index and the IFREMER classification scheme. Overall, we found a good agreement between β-values and macrophyte indicators. Furthermore, the specific exergy was calculated for 71 sites in coastal lagoons of Southern France and compared with existing classification schemes, finding a good agreement between them. As a result, we argue that specific exergy may be used as an integrated index that is able to synthesize and complement existing approaches.     

River dolphins can act as population trend indicators in degraded freshwater systems

Conservation attention on charismatic large vertebrates such as dolphins is often supported by the suggestion that these species represent surrogates for wider biodiversity, or act as indicators of ecosystem health. However, their capacity to act as indicators of patterns or trends in regional biodiversity has rarely been tested. An extensive new dataset of >300 last-sighting records for the Yangtze River dolphin or baiji and two formerly economically important fishes, the Yangtze paddlefish and Reeves' shad, all of which are probably now extinct in the Yangtze, was collected during an interview survey of fishing communities across the middle-lower Yangtze drainage. Untransformed last-sighting date frequency distributions for these species show similar decline curves over time, and the linear gradients of transformed last-sighting date series are not significantly different from each other, demonstrating that these species experienced correlated population declines in both timing and rate of decline. Whereas species may be expected to respond differently at the population level even in highly degraded ecosystems, highly vulnerable (e.g. migratory) species can therefore display very similar responses to extrinsic threats, even if they represent otherwise very different taxonomic, biological and ecological groupings. Monitoring the status of river dolphins or other megafauna therefore has the potential to provide wider information on the status of other threatened components of sympatric freshwater biotas, and so represents a potentially important monitoring tool for conservation management. We also show that interview surveys can provide robust quantitative data on relative population dynamics of different species.     

长江口轮虫生物多样性特征分析

长江口径流在南北支分布不均导致北支盐度高于南支,因此南北支之间生物群落存在一定差异。2010年在长江口分支前的江段和南北支设置5个断面,开展轮虫生态研究。分支前的太海汽渡断面处共采集到轮虫9种,隶属6科8属,其中优势种为没尾无柄轮虫、暗小异尾轮虫、萼花臂尾轮虫等;长江口南支2个断面共采集轮虫20种,隶属于6科12属,南支优势种为暗小异尾轮虫、盘状鞍甲轮虫和蹄形腔轮虫;长江口北支2个断面共采集轮虫11种,隶属于7科10属,北支优势种为舞跃无柄轮虫、没尾无柄轮虫和盘状鞍甲轮虫。南支轮虫种类、密度、多样性都高于北支,南北支的轮虫群落相似度较低。轮虫与水域环境因子相关性分析显示,盐度的差别影响了轮虫种类组成、密度和空间分布。     

苏州工业园区湖泊后生浮游动物群落结构及影响因子

苏州工业园区地处长江流域下游,随着城市化进程的不断推进,园区水生态系统结构与功能的稳定面临严峻考验。浮游动物作为水生态系统的重要组成部分,探究其群落结构的形成机制对生物多样性保护及生态系统健康发展具有重要意义。为深入了解苏州工业园区五个主要湖泊后生浮游动物群落结构的动态变化及影响因子,于2018年7月至2019年6月进行4次调查。研究共检出后生浮游动物112种（轮虫65种、枝角类29种、桡足类18种）,其中优势种12种（轮虫10种、枝角类和桡足类各1种）。Jaccard相似性分析表明,湖泊间后生浮游动物物种组成整体处于中等相似水平。后生浮游动物密度呈现出显著的季节和湖泊差异,而生物量、Shannon-Wiener多样性指数、Pielou均匀度指数以及Margalef丰富度指数仅存在显著的季节差异。聚类分析结果表明,夏季和秋季后生浮游动物群落结构最为相似。RDA分析表明,水温、溶解氧和pH是影响园区湖泊后生浮游动物群落结构的主要环境因子。Pearson相关性分析表明,湖泊面积与后生浮游动物群落结构无显著相关关系,样点近岸距离与生物量具有显著的正相关关系。基于水质评价标准和物种多样性指数可知,园区湖泊水质整体处于轻-中度污染水平。研究表明苏州工业园区五大湖泊后生浮游动物群落结构表现出同质化趋势;季节变化、环境因子以及样点近岸距离是调控群落结构形成的主要因素。     

近15年长江口海域海洋生物变化趋势及健康状况评价

对近15年（2004-2018年）长江口海域海洋生物变化趋势进行分析，评价海洋生物健康状况，并对陆源污染物排放与海洋生物变化进行相关性分析。结果表明，（1）长江口海域海洋生物群落结构组成发生了一定变化，与20世纪90年代末相比，浮游植物种类数有所减少，浮游动物、底栖生物种类数有所增加。浮游植物以硅藻为主，但甲藻占比有所增加，2010年以来硅藻、甲藻群落结构进入新的平衡状态；浮游动物以节肢动物为主，主要类群桡足类占比有所下降；底栖生物种类数明显升高。（2）生物多样性总体水平一般，浮游植物多样性指数总体较低，第一优势种的优势度较高；浮游动物多样性指数和丰富度指数多年呈现下降趋势；底栖生物多样性水平一般，优势种渐趋单一。（3）海洋生物总体处于"不健康"状态，主要影响指标为浮游植物密度偏高，浮游动物密度偏低、生物量偏高，底栖动物密度偏高、生物量偏低。生态系统变化与陆源主要污染物排放、营养结构变化及水体富营养化均具有一定的相关性，其中无机氮（DIN）、石油类入海通量与生物健康指数呈显著负相关关系（P < 0.05），无机磷（DIP）与底栖生物生物量呈显著负相关关系。N/P与浮游植物丰度呈显著负相关，但与浮游植物均匀度和多样性指数呈显著正相关；Si/N与浮游植物多样性指数呈显著负相关。海域严重富营养化面积比例与硅藻甲藻种类数比值呈显著正相关关系。     

Using high‐resolution multi‐spectral imagery to estimate habitat complexity in open‐canopy forests: can we predict ant community patterns?

The structure and composition of arthropod assemblages are strongly associated with habitat complexity. Accurate, time efficient estimates of habitat complexity may provide insights for biodiversity management in natural systems. We obtained high-resolution (0.7 m pixel) multi-spectral aerial imagery of National Parks 20 km north and 20 km south of Sydney, Australia. We explored both the Normalised Difference Vegetation Index (NDVI) and the standard deviation of reflectance in the near-infrared spectrum (stdevR_NIR) as indicators of low and high habitat complexity in sandstone forests north of Sydney. We then tested described predictions of ant community patterns (based on a previous study) using sites selected from high-resolution multi-spectral imagery in sandstone forests south of Sydney. Ground-scored habitat complexity was positively correlated with NDVIs and, to a lesser extent, stdevR_NIR values in sandstone forests north of Sydney. As predicted, ant species richness was negatively correlated with NDVIs in forests to the south of Sydney. Also, ant species composition was different in areas with contrasting NDVIs. The ant species driving composition differences responded to habitat complexity in a similar way in forests to the north, and south, of Sydney. The strong association we detected between NDVIs and habitat complexity, most likely reflects the relatively exposed nature of the vegetative layers in the forests we sampled. Remote sensing, integrated with quantitative research testing predictive faunal responses to vegetation structure and biomass at landscape scales, may provide efficient means of estimating biodiversity for management in particular habitats.     

Estimation of ecological exergy using weighing parameters determined from DNA contents of organisms – a case study

We studied the changes of exergy and specific exergy with data of benthic macrofauna communities, periodically sampled along an estuarine gradient of eutrophication in the Mondego estuary (Western Portugal). Exergy estimates were calculated from organism biomass, based on weighing factors for the relative content of exergy per unit of biomass determined from DNA contents of organisms. Results were discussed in terms of both the macrofauna biomass production and the structural organisation of the system. Estimates for the exergy indices provided useful indications for the evaluation of environmental impact due to the eutrophication process. Different average values for the indices of exergy and specific exergy were estimated relatively to areas with different levels of eutrophication, in the spatial gradient of eutrophication. Higher exergy levels and lower exergy content per unit of biomass (specific exergy) were associated to populations more stabilized or areas less perturbed. Additionally, the index of specific exergy seemed capable of providing indications for the qualitative alterations in the communities (in temporal and spatial terms) that go in the direction of the observations made in this ecosystem.     

Exergy as an indicator: Observations of an aquatic ecosystem model

Exergy is considered as a goal function or ecological orientor. Normally at the edge of oscillation exergy reaches to its maximum value when the ecosystem had no adaptation on it. To study the variation of exergy in different states of ecosystem, a simple three species (phytoplankton, zooplankton and fish) food chain model has been considered. From the model it is shown that the system moves from steady state to chaotic state by decreasing zooplankton body volume in turn increasing its grazing rate. By the property of self-adaptability the system tries to overcome this situation. Two such possible processes are described here: (i) by the toxic effect of phytoplankton and (ii) by reducing half saturation constant of fishes. In both this cases exergy value reduces and the system reaches to stable state. Through the analysis of exergy variation in all these situations this paper shows that the system chose the process in which the reduction of exergy will be the minimum.     

Exploring spatial indicators for biodiversity accounting

In the context of the System for Environmental-Economic Accounting, biodiversity accounting is being developed as a tool to monitor and increase the understanding of human impacts on biodiversity. Biodiversity accounting aims to structurally measure, monitor and map changes in multiple biodiversity components, as an integral part of a larger system of ecosystem accounts. Both indicators relevant for ecosystem functioning and indicators that reflect the non-use values of biodiversity can be included in biodiversity accounting. In this paper we focus on the latter, and we test the potential applicability of a set of species indicators for developing a biodiversity account in Limburg province, the Netherlands. In particular, we map and analyse a range of indicators reflecting species richness, the presence of rare and threatened species and species diversity. We test spatial correlation to identify the minimum set of indicators that would need to be included in the account. We also evaluate individual indicators using eight different criteria. We show that, in Limburg province, a set of indicators covering at least five species groups is required, and that it would be most meaningful to have indicators reflecting the occurrence of threatened species. However, data availability as well as the most suitable set of indicators are likely to differ between areas, and case studies in other countries are required to support the selection of indicators for biodiversity accounting in an international framework.