Biodiversity Investigation and Assess，ent of Yihe-Luohe River Basin in Henan Province

选取物种丰富度、生态系统类型多样性、物种特有性、受威胁物种丰富度、外来物种入侵度5个评价指标,以县域为评价单元,对河南省伊洛河流域13个县区展开生物多样性调查并进行综合评价,旨在系统掌握伊洛河流域生物多样性现状,为管理部门制定有效保护策略提供决策依据,并且进一步检验环保部已建立的生物多样性评价指标和方法.结果表明:流域内共有野生维管植物2882种;各类脊椎动物514种;自然分布的生态系统类型114种;中国特有物种1 107种;受威胁物种252种;外来入侵植物53种.上游卢氏、嵩县和栾川生物多样性评价结果为“高”,中游的洛宁、宜阳、伊川为“中”,而下游7个县区生物多样性均为“一般”.流域内生物多样性地域性差异较大.     

东安紫水国家湿地公园植物多样性评价

采用林分结构调查和线路踏查法,对湖南省东安紫水国家湿地公园植物多样性进行了调查,在层次分析法的基础上选取了物种丰富度、生态系统多样性、特有及稀有种和外来物种入侵4项指标,构建了植物多样性评价体系.同时调查统计了东安紫水湿地公园的植物组成、优势科属.结果表明:湖南省东安紫水国家湿地公园生态系统类型多样化且稳定性高,植物资源丰富;维管束植物有195科676属1100种,其中蕨类植物有31科56属92种,裸子植物有7科13属16种,被子植物有157科607属992种;被子植物是东安紫水湿地公园植物的重要组成部分,优势类群主要为禾亚科、菊科、蝶形花科、蔷薇科;植物多样性指数得分为76.92分.     

山东省自然保护区植物多样性研究

对山东省生物多样性较高的25个省级以上自然保护区的植物多样性进行了调查研究,发现共有175科918属2 362种维管束植物,保护了山东省93%以上的维管束植物物种。利用多种生物多样性测度方法分析表明,所研究的25个自然保护区中物种丰富度最高的为青岛崂山省级自然保护区,其次为泰山省级自然保护区和烟台昆嵛山国家级自然保护区。所研究的自然保护区内共有152种珍稀濒危植物,珍稀濒危植物物种丰富度最大的为青岛崂山省级自然保护区。研究区内共发现289种境外外来植物,其中入侵类有98种。所研究的自然保护区均受到了不同程度的境外外来植物入侵,境外外来植物中草本植物的数量远远多于木本植物的数量,且物种较为丰富的自然保护区境外外来植物物种数量也比较多。本研究可为山东省自然保护区植物多样性保护以及自然保护区管理提供科学依据。     

厦门大屿岛白鹭自然保护区外来入侵植物

近年来．入侵物种由于对生态系统、生物多样性以及社会经济造成严重的影响而受到越来越多的重视。入侵物种与全球变化的一些因素相互作用．对自然界和人类社会造成了严重损失．从而使生物入侵这一全球问题倍受关注。在美国．外来物种的扩散是导致生物多样性降低的第二大原因．对49％的濒危物种的生存有不良影响。在夏威夷．接近100％的濒危物种受到外来物种的威胁。美国每年与入侵物种相关的损失达1230亿美元．其中植物入侵占了很大的比例。每年我国几种主要外来入侵物种所造成的经济损失也高达574亿元．     

全球环境变化与生物入侵

全球环境变化将对地球生态系统的物种多样性及其分布产生重要而深远的影响:一方面可能使部分地区的生态系统对外来物种的抗性弱化;另一方面将激活外来物种的活性,导致外来生物的快速扩散和大规模入侵,进而排挤和"杀死"当地乡土物种,减少生物多样性,改变原有生态系统的组成、结构和功能.提出了加强对入侵物种的预测、监控,以及立足于生态系统和整个社会来应对生物入侵的策略,以期为预防和控制生物入侵提供参考.     

邛海湿地流域生物多样性评价

运用生物多样性理论,建立湿地生物多样性评价指标体系和赋值标准,对邛海湿地流域生物多样性进行评价分析。结果表明：邛海湿地流域生物多样性较好,物种丰富,特有属种多,生态系统结构复杂,生境类型较多。此外,“生境开发强度”指标分值相对偏低,表明人类活动对邛海湿地的侵扰较大,尤其是湿地流域内的农业生产活动和旅游开发活动对邛海湿地侵扰破坏较大。     

植物入侵对城市湿地生态系统中本地植物的影响

城市湿地不仅有着重要的生态和经济价值,同时还服务于城市居民的人文、审美需求等社会和文化的各个方面。然而随着经济全球一体化的发展,外来植物入侵对城市湿地生态环境和物种多样性已构成不可避免的威胁。城市湿地入侵植物对城市湿地生态系统中本地植物个体适合度、生理特性、种群遗传结构、种群数量、群落种间关系、本地植物多样性以及本地植物所处的生境等多方面造成严重影响。因此,应根据城市湿地本地植物遭受的影响,加强对城市湿地外来入侵植物的有效管理及对退化城市湿地生态系统的修复。     

我国外来生物入侵现状与生态安全

外来生物在丰富了区域生物物种的同时,也带来了一些负面影响,对生态环境、生物多样性和社会经济造成巨大危害.我国外来生物入侵现象越来越严重,入侵生物种类多,来源广泛;入侵面积大,被入侵的生态系统多;入侵范围不断扩大,潜在生态危害不可忽视.     

神秘生物入侵英国下水道

<正>近日,一种神秘的生物开始入侵英国的河流等水道,民众称其为"杀手虾",目前这个物种已经在英国确定了自己的地位,包括诺福克湖区等一些地方都可以看到这种入侵生物,似乎"杀手虾"已经将英国本土当成了自己的主场。对于英国生态学家而言,这并不是一个好消息,入侵生物在英国没有天敌时就可能出现大规模繁殖,并威胁到本地物种的生存。来自英国剑桥大学的研究人员大卫·奥尔德里奇博士对入侵英国的外来物种进行调查,发现在英     

外来物种入侵的微生物群落多样性研究

随着全球经济不断发展和往来,全球生态环境变化,外来物种入侵的问题正不断影响着地球环境,也是近年来全球持续关注的热点环境问题。人类赖以生存的地球上的生态系统具有丰富的多样性,其中各地的微生物群落有着稳定的生态系统、固定的生物循环,不能被轻易破坏,而外来物种入侵对于稳定的生态系统有着很大的威胁和很多的隐患问题存在,必须使用适当的措施加以整改。该研究以微生物群落为研究对象,探究外来入侵物种对微生物群落的原因、影响因素、入侵机制、近年来国内研究现状等方面,并就产生问题提出相应的防治措施。     

Ecosystem consequences of species richness and composition in pond food webs

Resolving current concerns about the role of biodiversity on ecosystems calls for understanding the separate roles of changes in species numbers and of composition. Recent work shows that primary productivity often, but not always, saturates with species richness within single trophic levels. However, any interpretation of such patterns must consider that variation in biodiversity is necessarily associated with changes in species composition (identity), and that changes in biodiversity often occur across multiple trophic levels. Here we present results from a mesocosm experiment in which we independently manipulated species richness and species composition across multiple trophic levels in pond food webs. In contrast to previous studies that focused on single trophic levels, we found that productivity is either idiosyncratic or increases with respect to species richness, and that richness influences trophic structure. However, the composition of species within richness levels can have equally or more marked effects on ecosystems than average effects of richness per se. Indirect evidence suggests that richness and associated changes in species composition affect ecosystem attributes through indirect effects and trophic interactions among species, features that are highly characteristic of natural, complex ecosystems.     

生物多样性研究发展态势与挑战

在文献调研、专家咨询和文献计量分析的基础上,对国际生物多样性研究的发展历程进行了回顾,分析了国际生物多样性研究的发展态势和挑战。分析结果表明,国际生物多样性研究热点主要集中在植物多样性开发、生态保护、物种丰度、基因多样性、可持续管理、气候变化、森林、土壤、生态系统等方面,并面临以下新的形势与挑战：（1）生物多样性科学已成为联系生物学各学科以及相关科学领域的综合交叉研究领域;（2）人类社会与生物多样性的交互关系是生物多样性研究的核心内容;（3）观测监测网络成为国际生物多样性研究的关键平台;（4）长期、持续和更广泛范围的生物多样性调查和监测成为重要的工作方向;（5）先进技术成为生物多样性研究和保护的重要手段;（6）生物多样性评估工作正成为生物多样性可持续利用的基础性工作。最后,根据国际研究进展与特点提出了加强我国生物多样性研究的建议。     

退耕还林工程影响下农林生态系统生态交错带的宽度测定

 生态交错带宽度的测定是定量研究其生态过程的基础,研究利用移动分割窗技术,对退耕还林工程影响下的山地农业生态系统和森林生态系统间的生态交错带宽度进行测定.首先以对生态交错带生物多样性分布趋势有较好体现的4个多样性指数(物种丰富度、Cody指数、群落相异性系数(β_J和β_S))和能体现群落本质特征的重要值为指标,取平方欧氏距离(SED)和Bray-Curtis系数(PD)为距离系数,采用移动分割窗技术分析比较.结果表明,物种丰富度,群落相异性系数β_J和β_S曲线趋势具有很好的重合性,同质区间也体现得较为明显,说明这3个指标生态学意义明显,有较高的实用价值;与PD相比,SED函数划分的结果要好.然后选取物种丰富度、群落相异性系数β_J和β_S作为指标以及SED作为距离系数对交错带的宽度进行测定.撂荒地-云南松林交错带位置约在样带序列25~36 m处,宽度为9 m,属于急变型交错带.     

Changes in plant community diversity and aboveground biomass along with altitude within an alpine meadow on the Three-River source region

The grassland is an important component of terrestrial ecosystems and plays a significant role in biodiversity and ecosystem functions.In the present study,the changes of plant species diversity and aboveground biomass productivity were examined along with the altitude in natural alpine grassland in the source region of three rivers on the Qinghai-Tibetan Plateau.Eleven experimental locations were selected with altitudes ranging from 3862 to 4450 m above sea level(a.s.l.).The results indicated that Kobresia pygmaea meadow,Kobresia humilis meadow and Salix cupularis shrub meadow had higher indices of diversity and aboveground biomass.The distribution of species diversity,richness and aboveground biomass showed similarly unimodal patterns across the altitude gradient with the highest indices appeared at mid-altitudes locations.The changing trend of species diversity,richness and evenness also showed significant unimodal patterns with total aboveground biomass,and the highest species diversity occurred at intermediate level of productivities.This research would provide a valuable reference for the protection of grassland biodiversity and maintaining of the grazing ecosystem function in the source region of the Three Rivers.     

生物多样性熵值测度指标的应用与分析

以一般生物多样性指标为基础．对熵值测度指标进行了研究，用熵值及其他多样性指标分析评价了新疆克拉玛依荒漠植被的生物多样性。结果表明，熵值测度指标与一般生物多样性指标在机理上有对应性，不仅可作为物种多样性、生态优势度、物种丰富度的优良评价指标，而且可以说明系统的物种对系统的贡献大小及其演化方向。     

Bottom-up effects of plant diversity on multitrophic interactions in a biodiversity experiment

Biodiversity is rapidly declining, and this may negatively affect ecosystem processes, including economically important ecosystem services. Previous studies have shown that biodiversity has positive effects on organisms and processes across trophic levels. However, only a few studies have so far incorporated an explicit food-web perspective. In an eight-year biodiversity experiment, we studied an unprecedented range of above- and below-ground organisms and multitrophic interactions. A multitrophic data set originating from a single long-term experiment allows mechanistic insights that would not be gained from meta-analysis of different experiments. Here we show that plant diversity effects dampen with increasing trophic level and degree of omnivory. This was true both for abundance and species richness of organisms. Furthermore, we present comprehensive above-ground/below-ground biodiversity food webs. Both above ground and below ground, herbivores responded more strongly to changes in plant diversity than did carnivores or omnivores. Density and richness of carnivorous taxa was independent of vegetation structure. Below-ground responses to plant diversity were consistently weaker than above-ground responses. Responses to increasing plant diversity were generally positive, but were negative for biological invasion, pathogen infestation and hyperparasitism. Our results suggest that plant diversity has strong bottom-up effects on multitrophic interaction networks, with particularly strong effects on lower trophic levels. Effects on higher trophic levels are indirectly mediated through bottom-up trophic cascades.     

柳江流域大型底栖动物群落结构及其与水质因子的关系

以柳江流域23个点位为例,研究了不同水文季节(3月和6月)水质因子(DO、COD_Mn、NH₃-N、As、Hg、Cd、Pb)对底栖动物群落结构的影响,2次调查共鉴定出底栖动物4门7纲16目54科68属(种),种类相似系数为83.76%,物种丰富度表现为枯水期略高于丰水期,底栖动物优势种在枯、丰水期分别有4种和2种,具有明显的季节演替. DCA和TWINSPAN分析结果显示:柳江流域底栖动物群落结构在时空分布上存在一定差异,主要表现为枯、丰水期均有3个不同的底栖动物类群大致依次分布在该流域干流及支流的源头、中上游及下游,群落内指示物种呈现出由清洁种逐渐过渡到耐污种的变化. 指示物种分析结果(ISA)显示:在枯水期,共有8种底栖动物能作为柳江源头和大环江上游群落的指示种,分别为四节蜉属(Baetis sp.)、锯形蜉(Serratella sp.)、溪泥甲一属(Zaitzevia sp.)、短脉纹石娥属(Cheumatopsyche sp.)、蜗虫(Dugesia sp.)、朝大蚊属(Antocha)、摇蚊属(Chironomus sp.)和细蜉属(Caenis sp.),其他类群无显著指示种;在丰水期,共有5种底栖动物能作为群落划分的指示种,其中,方格短沟蜷(Semisulcospira cancellata)、钉螺(Oncomelania sp.)是柳江中上游的指示种,汉森安春蜓(Amphigomphus hansoni)、河蚬(Corbicula fluminea)、卷扁螺(Gyraulus compressus)是柳江下游的指示种. CCA分析结果显示:COD_Mn和DO是枯、丰水期均对柳江流域底栖动物群落分布有重要影响的水质驱动因子,而重金属因子(Cd、Pb、Hg)在枯水期对底栖动物分布影响较大, NH₃-N在丰水期对底栖动物分布影响较大.     

内蒙古草原锡林河流域植物群落生物量及多样性沿土壤水分含量梯度的变化

在内蒙古草原锡林河流域土壤水分含量梯度上,测定土壤含水量并调查植物群落样方,探讨植物群落生物量及多样性沿水分梯度的变化.发现植物群落地上生物量和物种丰富度与土壤含水量之间呈显著的单峰关系;而香侬威纳指数和Pielous均匀度指数与土壤含水量之间不存在显著的相关关系.植物群落物种丰富度和香侬威纳指数与地上生物量之间呈显著的正相关关系;而Pielous均匀度指数与地上生物量之间不存在显著的相关关系.结果表明土壤含水量对半干旱草原植物群落的丰富度和生产力的影响极为显著,但不同土壤含水量对群落均匀性的影响有限,说明除土壤含水量外还有其他因素影响草原植物群落的结构.     

转基因农作物对生物多样性的影响

自 198 3年第一例转基因植物问世以来 ,转基因作物种类迅猛增加 ,种植的面积在不断扩大 ,也给人类带来了非常明显的经济效益。与此同时 ,人们已经注意到转基因作物对生物多样性已经或可能产生的影响 ;对遗传多样性的影响 ;对生态系统多样性的影响 ;对物种多样性的影响。     

High plant diversity is needed to maintain ecosystem services

Biodiversity is rapidly declining worldwide, and there is consensus that this can decrease ecosystem functioning and services. It remains unclear, though, whether few or many of the species in an ecosystem are needed to sustain the provisioning of ecosystem services. It has been hypothesized that most species would promote ecosystem services if many times, places, functions and environmental changes were considered; however, no previous study has considered all of these factors together. Here we show that 84% of the 147 grassland plant species studied in 17 biodiversity experiments promoted ecosystem functioning at least once. Different species promoted ecosystem functioning during different years, at different places, for different functions and under different environmental change scenarios. Furthermore, the species needed to provide one function during multiple years were not the same as those needed to provide multiple functions within one year. Our results indicate that even more species will be needed to maintain ecosystem functioning and services than previously suggested by studies that have either (1) considered only the number of species needed to promote one function under one set of environmental conditions, or (2) separately considered the importance of biodiversity for providing ecosystem functioning across multiple years, places, functions or environmental change scenarios. Therefore, although species may appear functionally redundant when one function is considered under one set of environmental conditions, many species are needed to maintain multiple functions at multiple times and places in a changing world.