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111.
生物多样性监测指标体系构建研究进展   总被引:13,自引:1,他引:13  
陈圣宾  蒋高明  高吉喜  李永庚  苏德 《生态学报》2008,28(10):5123-5132
生物多样性监测是为确定与预期标准相一致或相背离的程度,而对生物多样性进行定期或不定期的监视,目前已成为生物多样性研究和保护的热点问题。生物多样性监测指标则是一些简化的生物或环境特征参数,说明生物多样性现状和变化趋势,以及人类活动压力对生物多样性的影响,以促进科学界、政府和公众间的沟通,提高生物多样性管理水平。近10年来,国际组织、政府机构和各国学者对生物多样性指标体系的构建进行了大量的探索工作,取得了很多进展,其中有些指标已经应用于实际监测项目。本文综述了生物多样性监测指标筛选的一般标准和指标体系构建的主要理论,梳理目前已提出或应用的主要生物多样性监测指标,以期为我国构建国家或区域尺度生物多样性监测指标体系提供参考。在此基础上分析提出:生物多样性概念的泛化、指标含义模糊以及知识和数据的缺乏是构建生物多样性监测指标的主要困难。我国未来的生物多样性监测指标体系构建需要关注以下两个方面:(1)紧密联系实际,构建适应性的监测指标体系,加强对典型生态系统区域的监测;(2)发展经济社会发展方面的指标,分析生物多样性变化的驱动力,为生物多样性保护和区域可持续发展提供科学依据。  相似文献   
112.
Summary In the fragmented agricultural landscapes of temperate southern Australia, broad‐scale revegetation is underway to address multiple natural resource management issues. In particular, commercially‐driven fodder shrub plantings are increasingly being established on non‐saline land to fill the summer‐autumn feed gap in grazing systems. Little is known of the contribution that these and other planted woody perennial systems make to biodiversity conservation in multifunctional landscapes. In order to address this knowledge gap, a study was conducted in the southern Murray Mallee region of South Australia. Selected ecological indicators, including plant and bird communities, were sampled in spring 2008 and autumn 2009 in five planted saltbush sites and nearby areas of remnant vegetation and improved pasture. In general, remnant vegetation sites had higher biodiversity values than saltbush and pasture sites. Saltbush sites contained a diverse range of plants and birds, including a number of threatened bird species not found in adjacent pasture sites. Plant and bird communities showed significant variation across saltbush, pasture and remnant treatments and significant differences between seasons. This study demonstrates that saltbush plantings can provide at least partial habitat for some native biota within a highly modified agricultural landscape. Further research is being conducted on the way in which biota, such as birds, use available resources in these dynamic ecosystems. An examination of the effects of grazing on biodiversity in saltbush would improve the ability of landholders and regional natural resource management agencies in making informed land management decisions.  相似文献   
113.
《植物生态学报》1958,44(8):842
倒木是森林生态系统维持健康和更新的重要组成部分, 在倒木不同腐解阶段, 倒木上定植的苔藓植物组合的差异尚不清楚。为深入探讨倒木上苔藓植物组合变化规律及其影响因素, 该文对西藏色季拉山同一地点不同腐解程度的4株华山松(Pinus armandii)倒木上的苔藓植物进行了样方调查和数据分析。结果表明: 4株倒木上40个样方共有苔藓植物22科52种, 其中藓类13科38种, 苔类9科14种; 以恒有优势种为特征进行划分, 共得到14个物种组合。随着倒木腐解程度加大以及周围环境的不断改变, 生长其上的苔藓植物物种多样性逐渐增加, 但组合数量和苔藓总盖度却呈现先增大后减小的趋势。苔藓物种由耐旱性强的丛生型藓类, 如木灵藓科、白发藓科, 逐渐演替为喜阴湿环境、快速生长的垫状或毯状藓类, 如提灯藓科、羽藓科和青藓科。倒木苔藓植物组合空间结构复杂程度逐渐增大。倒木是多种苔藓植物选择的重要生长基质, 其上苔藓植物受倒木的腐解程度、水分和光照等条件的影响而发生相应的物种组合变化。  相似文献   
114.
115.
Soil microbes play key roles in ecosystems, yet the impact of their diversity on plant communities is still poorly understood. Here we demonstrate that the diversity of belowground plant-associated soil fungi promotes plant productivity and plant coexistence. Using additive partitioning of biodiversity effects developed in plant biodiversity studies, we demonstrate that this positive relationship can be driven by complementarity effects among soil fungi in one soil type and by a selection effect resulting from the fungal species that stimulated plant productivity the most in another soil type. Selection and complementarity effects among fungal species contributed to improving plant productivity up to 82% and 85%, respectively, above the average of the respective fungal species monocultures depending on the soil in which they were grown. These results also indicate that belowground diversity may act as insurance for maintaining plant productivity under differing environmental conditions.  相似文献   
116.
长江三峡淹没区与移民安置区植物多样性及其保护策略   总被引:5,自引:0,他引:5  
随着三峡大坝的修建,三峡地区淹没区和移民安置区的植物多样性调查与保护工作相继展开。从多年考察采集到的标本及历史资料补充确定,两区高等植物为170科,762属,1784种。分别占到三峡地区高等植物科、属、种数的85.85%,75.30%和59.19%。其中特有植物27种。而三峡地区的灌木和草丛群落基本分布在沿江两岸的低海拔地区,受水库蓄水影响较大。对两区内21个马尾松(Pinus massoniana)群落物种多样性进行的Shannon-Wiener指数及Pielou均匀度指数的测定结果表明,马尾松群落的多样性变化总体趋势为:灌木层>草本层>乔木层;对该地区具有代表性的11种灌丛类型进行的物种多样性指数的测定结果表明:盐肤木(Rhus chinensis)、毛黄栌(Cotinus coggygriavar.pubescens)、荆条(Vitex negundo)、马桑(Coriaria sinic)等4种群落的灌木层丰富度较高,分别为16,26,20和15。多样性指数分别为1.791,3.427,2.949和1.718;对沿江分布的9种主要草丛群落进行的物种多样性指数的测定结果表明:芒萁(Dicranopteris dichotoma)、五节芒(Miscanthus floridutus)、白茅(Imperatacylindricavar.major)、荩草(Arthraxon hispidus)等4种海拔分布较高的群落物种多样性指数较高,分别达到1.697,1.354,1.144和1.018。另外,对淹没区及移民安置区的物种调查结果显示:受淹的自然植被类型共有22种。其中木本群落4种,灌丛9种,草丛9种。小鞍叶羊蹄甲(Bauhinia brachycarpavar.microphylla)、中华蚊母树(Distylium chinensis)、水杨梅(Geum aleppicum)、小叶黄杨(Buxus sinica var.parvifolia)、铁仔(Myrsine africana)、疏花水柏枝(Myricaria laxiflora)等灌丛被全部淹没;巫溪叶底珠(Securinega wuxiensis)、宜昌黄杨(Buxus ichangensis)和荷叶铁线蕨(Adiantum reniformevar.sinense)大部分被淹没。目前,已建立了库区植物物种保护站及监测站,200多种植物已得到迁地保护,包括已列入中国植物红皮书的37种珍濒物种和11种三峡库区建群种。  相似文献   
117.
Short‐rotation woody cropping (SRWC) refers to silvicultural systems designed to produce woody biomass using short harvest cycles (1–15 years), intensive silvicultural techniques, high‐yielding varieties, and often coppice regeneration. Recent emphasis on alternatives to fossil fuels has spurred interest in producing SRWC on privately owned and intensively managed forests of North America. We examined potential bird and small mammal response at the stand level to conversion of existing, intensively managed forests to SRWCs using meta‐analysis of existing studies. We found 257 effect sizes for birds (243 effect sizes) and mammals (14 effect sizes) from 8 studies involving Populus spp. plantations. Diversity and abundance of bird guilds were lower on short‐rotation plantations compared with reference woodlands, while abundance of individual bird species was more variable and not consistently higher or lower on SRWC plantations. Shrub‐associated birds were more abundant on SRWC plantations, but forest‐associated and cavity‐nesting birds were less abundant. Effects on birds appeared to decrease with age of the SRWC plantation, but plantation age was also confounded with variation in the type of reference forest used for comparison. Both guilds and species of mammals were less abundant on SRWC plantations. These conclusions are tentative because none of these studies directly compared SRWC plantations to intensively managed forests. Plantations of SRWCs could contribute to overall landscape diversity in forest‐dominated landscapes by providing shrubby habitat structure for nonforest species. However, extensive conversion of mature or intensively managed forests to SRWC would likely decrease overall diversity, especially if they replace habitat types of high conservation value.  相似文献   
118.
Summary The composition of the ant community was assessed along standardized 100 m transects in annually flooded Varzea forest and in terra firme forests on sandy soil (Flanco forest) and on claytopped mesas (Planalto forest). Standardized samples were taken by unit-time hand collecting (day and night times), sweeping, beating, baiting and by Winkler sacks. A total of 156 species, representing 49 genera were found, of which 98, 88 and 55 were respectively found in the Planalto, Flanco and Varzea forests. Species lists are presented and the ant community composition and species richness are compared between the three forests. By considering the nesting and foraging habits of the various species, the differences in overall community composition are related to the forest type and susceptibility to inundation of the three forests which were surveyed.The data confirm the view that tropical rain forests support an extremely diverse ant fauna and comparisons with other forested areas suggest that ant species richness declines in subtropical and temperate rain forests. Although alpha diversity is high, species turnover between forests is lower than expected, suggesting that ant species richness in this forested region is not as great as is implied in some published estimates of global arthropod diversity.  相似文献   
119.
城市生态园林与生物多样性保护   总被引:65,自引:1,他引:65  
城市生态园林与生物多样性保护袁兴中,刘红(曲阜师范大学,273165)UrbanEcologicalgardeningandBiodiversityConservation.¥YuanXingzhong;LiuHong(De-partmentofBi...  相似文献   
120.
谢海生 《生态学报》1994,14(4):355-365
鄂尔多斯高原位于我国典型的生态过渡带,气候变化明显,系统反应敏感,因此,现有的主要用于植被和气候空间分类的有关植物与气候关系的模型和指数,均不适合用于鄂尔多斯高原生态过渡带气候。植物动态分析。为此,本文利用位于鄂尔多斯高原中部的伊金霍洛旗39a(1953-1991)气象资料,分析该地区的气候特点,构建一个可用于描述生态过渡带气候特征的气候植物生长指数,并用与植被动态密切相关的天然放牧条件下(1958-1979),该旗牲畜的存栏数和出栏数的历史资料代替植被动态资料,进行鄂尔多斯气候植物生长指数与天然放牧条件下牲畜的存栏数和出栏数的动态分析,构建其ARMAX模型。研究结果表明,鄂尔多斯高原气候敏感易变,降水年际变化大;高原光、温、水配合并不完全一致,光、温超前,降水滞后,天然植被生产力不高;气候植物生长指数与畜牧生产的动态分析结果表明,该地区在天然放牧情况下,主要依赖于牧场植被长势的畜牧生产与气候-植物生长指数密切相关,说明构建的气候植物生长指数确实在一定程度上反映了该地区的气候与植物生长的关系 ̄(6-8)。  相似文献   
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