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1.
海岛矿区岩质边坡植物群落演替中物种多样性的变化   总被引:4,自引:0,他引:4  
通过植物群落调查,采用Shannon多样性指数、Simpson优势度指数、Margalef丰富度指数和Pielou均匀度指数,结合DCA排序和一元线性回归分析,考察了舟山海岛矿区岩质边坡植物物种构成特征,研究了植物群落演替过程中生物多样性的变化。结果表明:研究区可划分为3个植物群落演替阶段(草本植物群落阶段、灌丛群落阶段和灌乔群落阶段);演替过程中,物种丰富度指数显著上升,多样性指数和优势度指数逐渐升高;具有矿区特殊生境适应性的植物配置在边坡植被恢复进程中与自然植被表现出一定的差异,演替过程依次为迁入物种生长期、迁入物种与人工导入种竞争期、迁入物种与人工导入种稳定共存期;人工导入群落演替后期的植物种大大加速了群落演替进程;合理的植物配置更能促进群落向正演替方向发展。  相似文献   

2.
安太堡矿区复垦地植被种间关系及土壤因子分析   总被引:1,自引:0,他引:1  
为研究安太堡矿区植被复垦过程中不同植物群落类型的种间关系及影响群落稳定性的外部环境因子, 作者对矿区的植物群落和自然生境进行了野外调查。对森林、灌丛和草地3种群落分别在10 m×10 m、 4 m×4 m和1 m×1 m的尺度上, 采用校正的χ2检验、Spearman秩相关分析研究了不同群落类型中出现频率较高的物种之间的联结性, 同时应用灰色关联识别对影响群落稳定性的土壤因子进行了识别。结果表明: 草地群落中物种组成贫乏, 以旱生种为优势类群, 物种间既具有一定的联结性, 又具有相当独立的分布格局。灌丛群落主要种整体呈现正联结, 其组成成分仍以旱生或中旱生物种为主, 部分中生性物种的出现及其与优势种的正相关关系都在一定程度上指示了灌丛群落向正向演替方向进行。森林群落主要种也整体呈现正联结, 表明群落处于植被演替进程中一个相对稳定的过渡阶段。土壤因子与植物群落稳定性的关联顺序为: 有机质> N > P> K> Cu> Mn > pH > Zn>电导率。总的来看, 矿区现有森林群落配置方式是较灌丛群落和草地群落配置方式更适合于矿区特殊生境的群落类型, 而土壤因子中有机质在决定群落稳定性方面发挥重要作用。此研究结果对制定该矿区植被恢复计划具有参考价值。  相似文献   

3.
贵州部分森林群落物种多样性初步研究   总被引:47,自引:1,他引:46       下载免费PDF全文
 本文根据贵州省178个森林群落样地的数据研究了群落物种的多样性。测定的指标有群 落物种丰富度,群落Simpson多样性指数和群落均匀度。测定结果表明;不同垂直带生物气 候条件下的森林群落有不同的多样性。相同垂直带生物气候条件下,基质生境相同时,不同森林植被亚型的群落的多样性近似,基质生境不同时,群落多样性则不同;同一群落类型的各个样地的多样性也有变化,结构不同的群落个体,其多样性指数不同,演替趋势也不同。乔木第二亚层的多样性普遍地高于乔木第一亚层。同一演替系列中,越接近顶极阶段多样性越高。多样性指数与群落物种丰富度,均匀度呈紧密的正相关,与群落个体总数没有相关。认为多样性测定在比较、说明群落的结构、类型、组织特征、生境、演替等方面有一定意义。  相似文献   

4.
大蜀山孤岛状山体植被演替阶段物种多样性变化规律   总被引:1,自引:0,他引:1  
采用"空间差异代替时间变化"的研究方法,以位于安徽省合肥市的孤岛状山体——大蜀山国家森林公园的恢复植被为研究对象,调查了16个典型样地,利用丰富度指数(Margalef richness index,R)、Shannon多样性指数(Shannon diversity index,H)、均匀度指数(Pielou evenness index,Jsw)和生态优势度指数(Simpson index,D)等研究了4个不同演替阶段森林群落的特征变化。结果表明:从马尾松林向针阔混交林、麻栎林的演替过程中,群落乔木层Shannon指数分别为1.957、1.485、0.738,呈下降的趋势;而短毛椴林乔木层Shannon指数为1.694。麻栎林乔木层的物种丰富度和多样性显著低于其他3个群落(P0.05),均匀度显著低于马尾松林和短毛椴林(P0.05)。4种群落灌木层、草本层之间的多样性和均匀度差异均不显著(P0.05)。在群落的垂直结构中,麻栎林物种多样性表现为灌木层草本层乔木层,其他3种群落的物种多样性则表现为灌木层乔木层草本层。处于演替顶极群落的物种多样性并不是最高,群落演替过程的稳定性和多样性有着更为复杂的关系。除人为活动的干扰外,群落的发育程度和内部生境是影响该区演替阶段群落物种多样性变化的主要因素。  相似文献   

5.
黄土区大型露天煤矿废弃地植被恢复过程中的植被动态   总被引:21,自引:0,他引:21  
生境再造与植被恢复是黄土区露天矿生态重建的核心 ,其中植被恢复是生态重建的保证。以我国平朔安太堡露天煤矿为例 ,采用野外调查、统计分析相结合的方法 ,对 1 985~ 2 0 0 1年矿区植被恢复过程中的植被动态进行研究。结果表明 :该区的人工植被经过演变 ,植物种的组成发生较大变化 ,由单一的物种组成结构逐渐发展为复杂的物种组成结构 ,并逐渐趋于动态的平衡。通过研究同一植物在不同配置模式下的生长情况 ,以及它们之间的相互影响 ,得出该区人工植被的较好模式为 :刺槐×油松×柠条、刺槐×油松、刺槐×沙棘和刺槐纯林。首次运用多样性指数、生态优势度、均匀度 ,对该区主要复垦植被群落进行分析 ,进一步预测了人工植被的演替方向 :刺槐林→刺槐林、沙棘林→沙棘林、沙棘×刺槐→刺槐、刺槐×油松→刺槐×油松和刺槐×油松×柠条→刺槐×油松×柠条。  相似文献   

6.
为探明石灰岩山地淡竹林演替的物种多样性变化及其驱动因子,采用空间代替时间的方法,分析了江西省瑞昌市淡竹林演替序列的淡竹纯林、竹阔混交林和阔叶林3类群落15个样地的物种组成、多样性指数和环境因子。结果表明,从淡竹纯林演替至竹阔混交林、阔叶林过程中:(1)群落的种、属和科的数目逐渐增加,而群落相似性系数降低;(2)木本和草本植物多样性均渐次升高,阔叶林与竹纯林相比有显著差异,但草本植物的Simpson指数和Pielou均匀度指数以混交林最高,群落类型间差异不显著;(3)全群落和草本物种丰富度、草本Shannon指数与土层厚度和裸岩率有较密切关系,而与土壤养分、水分含量等因子无显著相关。分析认为,石灰岩山地淡竹林至阔叶林的演替过程中,土壤的累积和质量改善可能是推动演替过程多样性升高的重要因素,这在石灰岩地区的植被恢复工作中需予重视。  相似文献   

7.
为揭示西双版纳布朗山植被恢复过程中处于不同演替阶段的蛛蜂物种多样性及其群落特征与植被恢复程度的关系,并对蛛蜂作为生态环境指示物的作用进行初步探讨,本研究在布朗山天籽生物多样性保护区内采用马氏网、黄盘等诱集法系统调查研究了草丛、稀树草丛、次生林、天然林4类逐步演替生境中的蛛蜂物种多样性及群落特征.共采集到蛛蜂个体2584头,隶属3亚科7族30属121种,其中某类生境特有的蛛蜂有53种,占总物种数的43%.次生林蛛蜂Shannon-Wiener多样性指数最高(3.03),天然林次之(2.97),草丛最低(2.43),Pielou均匀度指数与多样性指数趋势一致,Berger-Parker优势度指数则相反.采用Jaccard相似系数进行蛛蜂群落相似性比较,植被演替阶段越相近,蛛蜂群落组成越相似.研究结果表明,蛛蜂物种多样性及其群落特征与植被群落及其演替程度密切相关,随着恢复植被的演替,蛛蜂群落结构趋于复杂,物种多样性增加,各蛛蜂物种的个体数分布越均匀,优势种的优势程度越下降;IndVal指示值分析结果表明:布朗山植被恢复过程中,新沟蛛蜂待定种1 Eopompilus sp.1和新沟蛛蜂待定种3 Eopompilus sp.3可分别作为草丛生境与稀树草丛生境的指示物种,奥沟蛛蜂待定种1 Auplopus sp.1、舟山奥沟蛛蜂Auplopus chusanensis、扁腹沟蛛蜂待定种1 Minagenia sp.1、红股扁腹沟蛛蜂Minagenia fulvifemoralis 4种蛛蜂可作为草丛、稀树草丛、次生林、天然林4类生境变化的监测种.  相似文献   

8.
黔西北地区不同演替阶段植物群落结构与物种多样性特征   总被引:1,自引:0,他引:1  
何斌  李青  刘勇 《广西植物》2019,39(8):1029-1038
该文采用"空间代替时间"的方法,研究了贵州省威宁县喀斯特地区植被演替过程中的群落结构、物种组成、生活型谱和物种多样性的变化规律。结果表明:(1)该调查共记录到种子植物174种,隶属于52科117属,物种分布较多的有菊科、蔷薇科、禾本科、杜鹃花科、小檗科、唇形科、蓼科。(2)随着植被的正向演替,物种丰富度逐渐增加,群落结构趋于复杂,高位芽植物所占比例逐渐增大。(3)随着植被的恢复,群落层次分化逐渐明显,大径级植株所占比例呈现增加趋势。(4)随着植被的恢复,群落各层次的ShannonWiener多样性指数(H)、Simpson多样性指数(DS)、均匀度指数(J)和Margalef丰富度指数(DM)逐渐增加;不同演替阶段植物群落之间的Srensen相似系数呈现先上升后下降的趋势,Cody指数则表现为逐渐增加的趋势。黔西北地区不同演替阶段植物群落结构和物种多样性不同,建群种和关键种发生了明显变化,不同演替阶段植物群落结构和物种多样性的研究对喀斯特地区植被演替规律的认识和生态恢复具有重要意义。  相似文献   

9.
新疆喀纳斯湖北端河漫滩湿地植物群落演替   总被引:1,自引:0,他引:1  
对喀纳斯湖北端河漫滩湿地植物群落进行了调查取样,通过除趋势对应分析(detrended correspondence analysis,DCA)排序研究了群落演替的动态,同时采用Shannon多样性指数、Margalef丰富度指数、Simpson多样性指数和Pielou均匀度指数,分析了物种多样性在群落演替过程中的动态变化,并运用去势典范对应分析(detrended canonical correspondence analysis,DCCA)方法,分析了不同样方中土壤因子与群落多样性指数之间的关系。结果表明:1)该区域植物群落演替序列为泽生苔草群落→西伯利亚早熟禾群落→金露梅群落→沼桦群落→西伯利亚云杉群落;2)随着演替的进行,群落物种优势度显著增加,而物种多样性呈先增加后降低的趋势,金露梅群落最高;3)土壤含水量和群落物种优势度之间存在显著负相关。  相似文献   

10.
植被恢复过程物种多样性的动态特征变化反映了植被的恢复程度。本研究以膨润土-纤维复合的岩土渣场植被恢复技术(CSR工程技术)作为岩土渣场植被恢复的应用背景,以锦屏二级水电站岩土渣场为对象,通过对植被恢复群落的调查和物种多样性分析,研究了岩土渣场人工恢复群落物种多样性动态特征。结果表明:初期选取的植物普遍表现出对环境的适应性,且豆科植物在群落中占据着主要的优势;随时间加长,禾本科、菊科等多年生草本植物逐渐增多,在群落功能维持中占据重要地位;群落动态与多样性关系紧密,随演替进展群落物种组成与物种多样性增加,群落生态优势度下降,而均匀度增加,群落渐趋稳定。  相似文献   

11.
晋西吕梁山严村流域撂荒地植物群落替中的物种多样性变化   总被引:20,自引:0,他引:20  
用DCA排序研究了黄土丘陵区撂荒地上植物群落演替的趋势和方向,用6种多样性指数分析了物种丰富度、均匀度和综合多样性在演替过程中的变化。随着演替的进展,物种丰富性显著增高,均匀性逐渐降低,综合多样性逐渐升高。  相似文献   

12.
In Lake Volvi, phytoplankton dominance was examined in relation to the main phases of the fluctuating physical state of the water column and nutrient levels. Four stages of algal succession were identified. The successional pattern was, in general, similar from year to year. External disturbances such as increased wind mixing and high floods had the effect of setting the succession back to an earlier stage.Nanoplanktic diatoms and flagellates dominated during the first stages of succession. The succession was running from r-selected species in early stages to K-strategists in summer and towards a mixed community in the terminal stage.Diversity was expressed by the indices of Gleason and Shannon (based on physical units and biomass). Interpretation of species diversity took into account the differential variations of its two components, the number of species and the evenness of their distribution. Diversity was more affected by evenness than by number of species.Diversity increased in late stages of succession corresponding to the complexity of the community (high number of species, high evenness). Physical disturbances influenced positively the diversity. The maximal diversity appeared in the transition periods between the compositional changes generated by disturbances and the true successional development. Disturbances may generate a more uniform distribution of diversity throughout the whole water column.The role of physical disturbances in increasing the phytoplankton diversity may be demonstrated from comparisons of diversity — evenness — species number of the same stages under different meteorological conditions.  相似文献   

13.
We present an interlaboratory comparison between full-length 16S rRNA gene sequence analysis and terminal restriction fragment length polymorphism (TRFLP) for microbial communities hosted on seafloor basaltic lavas, with the goal of evaluating how similarly these two different DNA-based methods used in two independent labs would estimate the microbial diversity of the same basalt samples. Two samples were selected for these analyses based on differences detected in the overall levels of microbial diversity between them. Richness estimators indicate that TRFLP analysis significantly underestimates the richness of the relatively high-diversity seafloor basalt microbial community: at least 50% of species from the high-diversity site are missed by TRFLP. However, both methods reveal similar dominant species from the samples, and they predict similar levels of relative diversity between the two samples. Importantly, these results suggest that DNA-extraction or PCR-related bias between the two laboratories is minimal. We conclude that TRFLP may be useful for relative comparisons of diversity between basalt samples, for identifying dominant species, and for estimating the richness and evenness of low-diversity, skewed populations of seafloor basalt microbial communities, but that TRFLP may miss a majority of species in relatively highly diverse samples.  相似文献   

14.
选择合适的物种多样性测度指标与多样性指数是进行群落多样性研究的基础工作。依据塔里木河上游荒漠河岸林样地调查资料,分别采用重要值、盖度和多度为测度指标比较了反映群落物种丰富度、多样性、均匀度和优势度12种多样性指数与异质生境群落多样性特征,并对多样性指数进行了相关分析与评价。结果表明,荒漠河岸林异质生境群落物种组成种类差异明显,轮南镇胡杨群落物种丰富度与多样性指数最高,水工三连灰胡杨群落多样性最低,土壤水盐的空间异质性是引起荒漠植被空间分布与群落多样性差异的主导因子。表征荒漠群落多样性以重要值和盖度为测度指标优于多度指标,其中以重要值为测度指标来反映群落多样性更为合理。相关与主成分分析表明,均匀度与多样性指数间的相关性高于丰富度与多样性指数,且多样性指数受均匀度、优势度指数受丰富度影响较大,反映出荒漠河岸林群落多样性主要决定于物种分布的均匀程度。12种多样性指数中Margalef丰富度指数(Ma)、Shannon-Weiner多样性指数(H)与Simpson多样性指数(D)能客观真实地反映异质生境荒漠植物群落多样性。同时,针对高度生境异质性的荒漠植物群落,还应综合考虑群落物种组成与生境特征,选择合适的多样性指数组合可更客观地反映荒漠河岸林群落多样性变化。  相似文献   

15.
Succession is one of the most studied processes in ecology and succession theory provides strong predictability. However, few attempts have been made to influence the course of succession thereby testing the hypothesis that passing through one stage is essential before entering the next one. At each stage of succession ecosystem processes may be affected by the diversity of species present, but there is little empirical evidence showing that plant species diversity may affect succession. On ex-arable land, a major constraint of vegetation succession is the dominance of perennial early-successional (arable weed) species. Our aim was to change the initial vegetation succession by the direct sowing of later-successional plant species. The hypothesis was tested that a diverse plant species mixture would be more successful in weed suppression than species-poor mixtures. In order to provide a robust test including a wide range of environmental conditions and plant species, experiments were carried out at five sites across Europe. At each site, an identical experiment was set up, albeit that the plant species composition of the sown mixtures differed from site to site. Results of the 2-year study showed that diverse plant species mixtures were more effective at reducing the number of natural colonisers (mainly weeds from the seed bank) than the average low-diversity treatment. However, the effect of the low-diversity treatment depended on the composition of the species mixture. Thus, the effect of enhanced species diversity strongly depended on the species composition of the low-diversity treatments used for comparison. The effects of high-diversity plant species mixtures on weed suppression differed between sites. Low-productivity sites gave the weakest response to the diversity treatments. These differences among sites did not change the general pattern. The present results have implications for understanding biological invasions. It has been hypothesised that alien species are more likely to invade species-poor communities than communities with high diversity. However, our results show that the identity of the local species matters. This may explain, at least partly, controversial results of studies on the relation between local diversity and the probability of being invaded by aliens. Received: 13 July 1999 / Accepted: 4 February 2000  相似文献   

16.
森林群落物种多样性格局和动态一直是生态学的研究热点,人工林弃管后演替进程中物种多样性变化也很值得研究。杉木(Cunninghamia lanceolata)作为我国南方林区人工栽培最广、经济价值最高的用材树种之一,其人工林分布面积很大,通常群落结构简单、物种多样性低,然而群落中杉木数量如何影响植物物种多样性,迄今缺乏研究。在浙江省自然保护区内,选择不同疏伐强度和弃管时间的杉木人工林,建立了6个1 hm~2长期动态监测样地,在10 m×10 m、20 m×20 m、50 m×50 m和100 m×100 m尺度下,探究群落物种多样性(物种丰富度、Simpson指数、Shannon-Wiener指数和Pielou均匀度指数)的变化规律,分析杉木数量(多度和相对多度)对物种多样性的影响。结果显示:弃管前对杉木林的疏伐强度越高,演替恢复后的群落物种多样性越高。相同疏伐程度下,物种多样性随演替时间的延长有先升高后降低的趋势。取样尺度小于100 m×100 m时,杉木数量与物种多样性呈极显著负相关;100 m×100 m尺度下仅杉木相对多度与3种多样性指数呈显著负相关,杉木多度与各物种多样性均无显...  相似文献   

17.
鼎湖山植物群落多样性的研究   总被引:83,自引:1,他引:82  
根据鼎湖山自然保护区16个植物群落的样地调查资料,从种丰富度和不同类型的物种多样性指数、均匀度与植被类型、人为干扰程度、演替阶段等方面的关系进行了分析。本区植被类型的多样性指数、均匀率指数变化反映了其结构复杂程度、生境的差异。物种丰富和多样性随着人为干扰程度的增强而降低。群落内各层的物种丰富度的大小的顺序为“灌木层>草本层>乔木层”,而群落多样性指数的大小顺序为“灌木层>乔木层>草本层”。群落多样  相似文献   

18.
陕西子午岭植物群落演替过程中物种多样性变化与环境解释   总被引:18,自引:2,他引:16  
采用空间代替时间的方法研究了黄土高原子午岭植物群落自然演替过程中不同层α物种多样性的变化规律,并通过CCA分析了物种多样性与环境间的关系。结果表明:(1)随演替的进展,草本层物种丰富度、均匀度及物种多样性均逐渐降低(P0.05);灌木层物种的丰富度与物种多样性均呈现相似的"J"形变化趋势,而均匀度(虎榛子(Ostryopsis davidiana)群落除外)差异不显著(P0.05);乔木层物种丰富度、均匀度以及物种多样性差异均不显著(P0.05);群落总体物种丰富度随演替进展呈现明显的单峰模型,与中期物种丰富度假说一致。(2)林冠郁闭度是影响草本层和灌木层物种组成的主要环境因子(P0.01),其次为土壤养分和坡位;而坡位对乔木层物种组成的影响极显著(P0.01),这可能与乔木树种的更新差异有关。(3)群落演替是物种扩散和环境筛综合作用的过程,物种对演替过程中变化光照资源的响应差异可能是该区不同层物种多样性变化的主要原因。  相似文献   

19.
黑龙江省东部山区森林植物物种多样性的研究   总被引:1,自引:0,他引:1  
王庆贵  邢亚娟 《植物研究》2007,27(1):125-128
通过对黑龙江省东部山区原始阔叶红松林和次生林物种多样性的比较研究,结合定量化的群落动态和环境梯度,分析论证了演替阶段、环境梯度、生长状况及干扰与物种多样性的相关关系。结论如下:次生林物种多样性高于原始阔叶红松林,但均匀度较原始林小;物种多样性较高的群落其森林生产力中等,森林生产力较大的群落其物种多样性小;中度干扰的群落,其物种多样性较高,而重度和轻度干扰的群落,其多样性低;物种多样性指数从演替初期到中期不断增加,到演替后期逐渐下降。  相似文献   

20.
The species diversity indices and the species abundance distribution of Ouercus ilex L. woods in Veneto, Italy were studied. The results are as follows: 1. The Menhinicht s index, Shannont s index, Brillouin’s index, Simpsont s index Piulout s evenness, V′ evenness of PIE, V evenness of PIE, Mclntosh evenness could be used to study the diversity of O. ilex woods in Veneto. They showed that from the area of Lago ki Garda, to Foci del Tagliamento, Bosco Nordio, and Colli Euganei, the value of species diversity indices decreased gadually. 2. The geometric series of species abundance distribution dould be used best to study the diversity of O. ilex woods, and the log-normal distribution of species abundance distribution could also be a good index used to study did. The results of the study of species abundance distribution were the same as those of species diversity indices. 3. Diversity did not always increase in succession. In the earlier stage of succession, the diversity usually was relatively large owing to the invasion of many species and the lack of dominance. In the subsequent stage, the diversity was relatively minimized as the dominance increases. In the late stage, the diversity would increase as the structure of community became complicated and the number of species increased.  相似文献   

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