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1.
对四川中亚热带扁刺栲-华木荷林区20 a生日本落叶松人工纯林(P1)、人工促进针阔混交林(P2)和次生阔叶林(P3)的森林植物群落进行了调查和分析。结果表明,P1、P2和P3的物种丰富度(S)分别为55、69和45;Shannon-W iener多样性指数分别为3.39±0.26、3.77±0.14和3.14±0.31,其差异显著(P<0.05);P2物种多样性最高,P1物种多样性次之,P3物种多样性最低。采伐迹地的不同恢复和重建措施对森林群落以及对群落乔木层、灌木层和草本的物种多样性有显著影响(P<0.001),但对森林群落不同层次物种多样性的影响强度不同,对草本层物种多样性影响强度较大。  相似文献   

2.
通过样地调查,采用Patrick物种丰富度指数(S)、Shannon-Wiener多样性指数(H)、Simpson优势度指数(D)、Alatalo均匀度指数(E)、Pielou均匀度指数分析比较了元谋干热河谷10个主要自然植物群落与人工林群落的物种多样性,并测定了不同群落的土壤养分.结果表明:(1)元谋干热河谷主要植物群落的多样性水平较低,S、H、D值分别为3.92319.583、0.9132.000和0.1780.510,且人工植物群落的S值明显低于自然植物群落,具优势种乔木群落的H值较高,人工植物群落E值大于自然植物群落的特点;(2)物种多样性与植物生长型的分析表明,按S指数排序为乔木层<草本层<灌木层;按H指数排序为乔木层<草本层<灌木层;按D指数排序为乔木层>草本层>灌木层;(3)自然植物群落对立地土壤的维持明显高于人工植物群落,前者的有机质、全氮、全磷、水解氮、速效钾明显高于后者.  相似文献   

3.
【目的】分析和比较物种多样性(物种丰富度、物种Shannon-Wiener指数和物种均匀度)、结构多样性(胸径Shannon-Wiener指数、胸径均匀度、胸径变异系数和胸径基尼系数)以及环境因素对秦岭太白山北坡锐齿栎林地上生物量的影响,为促进秦岭生物多样性保护和森林生态系统功能协调发展提供理论依据。【方法】以秦岭太白山北坡锐齿栎林为对象,基于1.5 hm2固定监测样地中所有胸径≥1 cm木本植物调查数据,利用多元线性回归分析物种多样性和结构多样性与地上生物量的相关性。通过构建结构方程模型并结合环境因素,比较物种多样性和结构多样性对地上生物量的作用效应。【结果】线性回归模型和结构方程模型的分析结果均显示:表示物种多样性的3个指标与地上生物量均无显著相关性,表示结构多样性的指标中,只有胸径均匀度与地上生物量呈显著负相关性,但胸径均匀度对地上生物量变异的解释能力却很低。环境因子对地上生物量的影响同时存在直接和间接效应,但直接效应起到主要作用。【结论】群落结构是影响太白山锐齿栎林地上生物量的重要因素;但结构多样性对地上生物量的作用效应是抑制而非促进,说明增加群落结构的复杂性反而不利于地上生物量的累积。环境因素直接影响地上生物量,但对物种多样性和结构多样性与地上生物量的关系无显著影响。本研究证实了群落结构对森林地上生物量的重要性,但这并不能说明群落结构是影响太白山次生锐齿栎林地上生物量的主导因素。  相似文献   

4.
【目的】为了解土地利用方式对西洞庭湖洲滩湿地生态系统服务功能的影响,探索土壤含水率和物种丰富度在湿地恢复过程中所起的作用,进而为今后西洞庭湖湿地恢复工程提供指导。【方法】于2015年冬季通过收割法和生物量模型对杨树种植区域、退林还湿区域、天然洲滩这3个区域间的土壤含水率、物种丰富度和植物地上生物量差异及土壤含水率和物种丰富度与地上生物量相关性进行了初步探究。【结果】1)不同土地利用方式下洲滩土壤含水率与物种丰富度差异显著;天然洲滩土壤含水率最高,退林还湿区最低,杨树种植区和退林还湿区物种丰富度高于天然洲滩。2)不同土地利用方式下洲滩植被地上生物量差异显著;杨树林种植区的植物地上生物量高于天然洲滩,而退林还湿区与天然洲滩无差异;草本植物地上生物量呈现出天然洲滩区最高、杨树林种植区最低的规律。3)不同土地利用方式下土壤含水率与草本植物地上生物量呈正相关,物种丰富度与草本植物地上生物量呈负相关。【结论】利用和恢复工程对洲滩湿地土壤含水率和物种丰富度存在影响;土地利用方式对洲滩湿地生态系统功能存在影响;土壤含水率和物种丰富度对于修复退化湿地及生态系统功能具有重要意义。后续退林还湿工程开展可考虑人为增加土壤含水率以及移植苔草等优势物种等人工辅助措施,以促进退林还湿区域向天然洲滩湿地的演替。  相似文献   

5.
通过对额济纳旗国家公益林进行监测与评价,结果表明:(1)额济纳旗国家级公益林胡杨和柽柳群落盖度平均增加2.69%、梭梭降低1.89%、白刺降低0.30%、沙拐枣降低0.42%。(2)胡杨、柽柳和白刺群落生物量均有不同程度的增加,生物量增加2.13 g·m~(-2);梭梭和沙拐枣群落生物量均有所减少。(3)额济纳旗7种主要植物群落的Margalef丰富度指数平均值为0.963,有较大幅度的增加,Shannon-Weiner多样性指数主要物种均有增加。Simpson's优势度指数沙拐枣有减小趋势,减幅均接近于0.03,其余植物群落均有增加。Pielou均匀度指数大多物种均呈增加趋势,尤以白刺增幅最大。  相似文献   

6.
为改良恢复已退化的草地,于2012年在退化草地上设置切根、围栏封育、浅耕翻等3种措施,与同期设置的由自由放牧引起的退化草地作为对照,并于2020年生长季高峰期对植物群落地上生物量、多样性等指标进行调查,结果表明:(1)与退化草地相比,实施改良措施9 a后,3种改良措施均可以显著提高植物群落地上生物量(P<0.05),且浅耕翻方式最好;3种改良措施均显著提高了群落中根茎型禾草的地上生物量(浅耕翻>切根>围栏封育>对照),而显著降低了丛生型禾草的地上生物量(对照>围栏封育>切根>浅耕翻)。(2)群落物种多样性在围栏封育下具有明显升高趋势,在浅耕翻和切根方式下均呈显著降低趋势,且群落物种多样性在切根方式下显著低于浅耕翻(P<0.05)。(3)群落中丛生型禾草地上生物量与群落物种多样性呈显著正相关关系(P<0.05),而根茎型禾草地上生物量与群落物种多样性呈极显著负相关关系(P<0.01)。综上所述,3种改良措施中,长期围栏封育对于多样性的维持具有一定促进作用,浅耕翻措施对群落生物量的恢复和提高具有较好效果。  相似文献   

7.
武夷山国家级自然保护区植物物种多样性研究   总被引:44,自引:0,他引:44  
兰思仁 《林业科学》2003,39(1):36-43
以植物群落调查样地资料为基础,从不同类型、不同层次的物种丰富度、多样性指数及均匀度指数对武夷山国家级自然保护区植物群落多样性进行了分析。本区植物群落多样性的变化规律为:物种丰富度、多样性指数及均匀度随该区植被演替趋势从针叶林、针阔叶混交林到常 阔叶林而增加,群落间变幅较大;植物生长型在物种丰富度、多样性指数及均匀度等多样性指数上均表现出灌木层>乔木层的规律。毛竹林作为一种重要的植被类型,其灌木层物种多样性高于其它3种森林类型,但由于毛竹是无性繁殖,其在林分中占绝对优势,故乔木层物种多样性明显低于其它3种森林类型。  相似文献   

8.
为探析喀斯特山地城市生物多样性特征及其影响因素,以黔中典型多山城市——安顺市为研究对象,运用生物多样性相关理论与方法,分析了安顺市植物物种多样性特征及其影响因素。结果表明:(1)安顺市植物群落物种多样性指数偏低,不同空间区域中差异较大,西南片区和中心区域低而东北片区最高;(2)不同绿地类型中植物群落物种多样性指数由高到低的顺序为区域绿地、公园绿地、附属绿地、防护绿地、广场绿地;(3)在不同方位中较为发达的中心城区与西南方位上多样性较低,东北方位最高;(4)自然绿地的植物群落物种多样性高于人工绿地和半人工、半自然绿地;(5)海拔1400 m以上区域的多样性高于海拔1400 m以下的区域。城市内植物群落物种多样性受地形地貌和城市发展的影响表现出较大的差异性,通过采取相应措施来调节人类活动与自然环境之间的关系,合理构建生态廊道,加强不同类型生境间的内在联系,让城市内的生态得到更好的保护与发展。  相似文献   

9.
桉树林分改造模式对林下植被物种多样性的影响   总被引:1,自引:0,他引:1  
对山美水库周边8年生桉树水源涵养人工林进行间伐和套种阔叶树种改造试验,以纯林作对照,3 a后比较不同改造模式对群落物种组成、物种多样性和林分生长状况的影响。结果表明:(1)与对照林分相比,不同改造模式林下不同层次物种的科、属、种类和数量总体上有所增加,但优势种有所变化;(2)各模式林分不同层次的Margalef丰富度指数虽然较原有纯林的有一定的提高,但Hurlbert均匀度指数和Simpson、Shannon-Wiener多样性指数总体上差异不显著;(3)皆伐桉树林后改种阔叶树的林分地上部分生物量现存量与枝叶生物量现存量显著高于择伐桉树后套种阔叶树的林分;(4)不同阔叶树种套种后生长适宜性依次为马占相思枫香台湾相思火力楠。  相似文献   

10.
以中村林场大庙岭油松-辽东栎混交林为研究对象,采用典型样地调查法,运用Patric丰富度指数、Simpson和Shannon-Wiener多样性指数、Pielou均匀度指数研究目标树全林经营前后林下灌草多样性的变化。结果表明:1)抚育后林下灌木层、草本层物种多样性都有增加,说明目标树全林经营有利于增加林下物种多样性。2)灌木层物种各指数在经营前后差异极显著(P0.01),草本层丰富度指数、多样性指数差异不显著(P0.05),均匀度指数降低,差异极显著(P0.01),这说明目标树全林经营对灌木层多样性影响较大;经营后灌木层均匀度增加,草本层物种均匀度降低。3)林下结构多样性受灌木层和草本层的综合影响,不同层次的物种对林下物种多样性的贡献不同,松栎混交林下多样性主要由灌木层决定。  相似文献   

11.
In order to ensure the sustainability of agroecosystems, biodiversity must be a priority. Agroforestry, which includes trees, is an example of such diverse systems. We evaluated plant diversity and aboveground biomass production to assess whether areas under fallow following traditional cultivation return to their initial condition. Also, plant diversity and aboveground biomass production were assessed in agroforestry systems (AFS) to determine if these were similar to unmanaged ecosystems. Another objective of the study was to observe the influence of plant diversity on aboveground biomass production in plant communities and also in the population of the dominant species, Cordia oncocalyx. Plant diversity was evaluated by assessing species richness, as well as using Shannon’s (H′) and Pielou’s (J′) indices. Aboveground plant biomass was evaluated in two AFS: agrosilvopastoral (ASP) and silvopastoral (SP), and also in a traditionally managed agricultural system (AG), areas that had been under fallow for six years (F6) and nine years (F9) and an area of unmanaged caatinga (CAT) vegetation. We observed that the ASP system had a lower diversity and number of species, especially tree species. However, it sustained the same total biomass production as CAT and fallow areas. The SP system, despite having lower H′ and J′ indices as well as lower total biomass production, had a similar number of species to CAT and cropped and fallow systems AG, F6 and F9. Plant biomass in F6 and F9 had recovered to productivity levels of unmanaged CAT vegetation; however the diversity indices were not restored to the same level. Plant diversity did not have an effect on the productivity of the agroecosystems. Likewise, annual biomass production by C. oncocalyx is not dependent upon diversity, but it is influenced by the growth stage of individuals.  相似文献   

12.
以湖南桑植县石漠化区为研究对象,采用样方调查法对3个不同石漠化等级样地进行植被调查,分析不同石漠化等级植物物种组成结构及植物多样性指数差异,并根据Jaccard群落相似性原理进行不同石漠化等级植物群落间的相似度评价分析.结果表明:调查区共出现草本植物23科39种、木本植物26科38种,优势科为菊科、蔷薇科、百合科、禾本...  相似文献   

13.
Assessing the characteristics of seed supply will be vital to better understand the dynamics of forest regeneration. In this study, we surveyed the aboveground vegetation, the seed rain, the seed bank, and natural seedling emergence in four typical 24-year-old plantations (eucalyptus, mixed-native, mixed-legume, and mixed-conifer) and a naturally successioned shrubland in southern China. The dominant species in the understory were similar among the five plant communities. The seed rain and the seed bank were dominated by shrubs and herbs but indigenous tree species were rare. Species that were common to all five-plant communities represented a great proportion of the seeds in the seed rain and seed bank. The seed rain consisted mostly of seeds derived from the local plant community. Seed abundance was greater in the seed bank than in the seed rain, and species richness was greater in the seed bank and in the corresponding plant community than in the seed rain. Species composition similarity between the seed rain, the seed bank, and the aboveground vegetation was low, because the seed rain contained much fewer species, and the seed bank and aboveground vegetation contained many different species, respectively. These findings indicate that both the seed rain and the seed bank play important roles in providing seeds for plant recruitment in the understory, but the seed bank contributes more than the current seed rain to the diversity of recruited plants. The current plant community has little impact on the qualitative composition of the seed rain and seed bank. Based on these data, it appears that succession to the desired zonal, mature forest community is unlikely to result from seeds in the seed rain or seed bank. Lack of seed availability of desired zonal mature forest species is the main bottleneck currently limiting succession in the plantations. Reintroduction of late-successional species could facilitate the desired succession.  相似文献   

14.
Wetland restoration had been implemented for more than two decades in Sanjiang Plain,Northeast China.To assess the restoration efficiency of wetland vegetation,we investigated plants composition of community,plant species diversity and aboveground biomass of restored sites in a chronosequence of restoration(1,2,3,6,8,11,15 and 25 years) in the Sanjiang Nature Reserve.As comparison,we also investigated the same factors in a cropland and a natural marsh adjacent to the restored sites.The results showed that wetland plant species can invade quickly after croplands were abandoned when there were suitable hydrology conditions.On the early stage of the restoration,weeds were main plant species in the restored sites.Wetland species appeared at the same time but differed from the dominant species from the adjacent natural marshes.Common native wetland species could dominance the community after 3-year restoration.Species richness and diversity increased on the early stage,and then decreased to the similar level of the natural marsh with the extension of restoration.Plant biomass could restore easier than the species composition and diversity.Our results indicated that plant species composition and diversity of abandoned reclaimed wetlands can restore gradually by natural succession in S anjiang Plain.However,25-year restoration site had similarity index of only 56% with the natural marsh,which revealed that two decades are not enough for complete restoration of vegetation.  相似文献   

15.
岷江上游干旱河谷区植被特征与多样性研究   总被引:1,自引:0,他引:1  
岷江上游干旱河谷区特征与植物多样研究表明:1)植物种类贫乏,有明显的重点科;并以的豆科Leguminosae、菊科Compositae、蔷薇科Rosaceae和禾本科Graminea等被子植物种类较大。2)对阴、阳坡不同海拔灌丛植被α多样性的的测度表明,各样地灌丛群落灌木和草本的物种多样性H与丰富度S、均匀度E成正相关关系,而与优势度D呈相反关系;植物群落物种α多样性指标在阴坡随海拔升高表现出明显的直线上升增加趋势,阳坡呈现出中间低两边高近似“U”型的海拔梯度格局;草本具有和灌木多样性指数相似的海拔梯度格局。3)低海拔梯度和高海拔梯度的灌丛植物种类和群落生境有较大的差异;随着海拔的升高,相似性减小,物种更替速率增大,灌丛群落的β多样性具有明显的变化规律。  相似文献   

16.
We investigated characteristics (scales and composition) of soil seed banks at eight study sites in the rocky mountain region of Beijing by seed identification and germination monitoring. We also surveyed the vegetation communities at the eight study sites to explore the role of soil seed banks in vegetation restoration. The storage capacity of soil seed banks at the eight sites ranked from 766.26 to 2461.92 seeds·m -2 . A total of 23 plant species were found in soil seed banks, of which 63 80% of seeds were herbs in various soil layers and 60% of seeds were located in the soil layer at 0 5cm depth. Biodiversity indices indicated clear differences in species diversity of soil seed banks among different plant communities. The species composition of aboveground vegetation showed low similarity with that based on soil seed banks. In the above- ground plant community, the afforestation tree species showed high importance values. The plant species originating from soil seed banks represented natural regeneration, which also showed relatively high importance values. This study suggests that in the rocky mountain region of Beijing the soil seed banks played a key role in the transformation from pure plantation forest to near-natural forest, promoting natural ecological processes, and the role of the seed banks in vegetation restoration was important to the improvement of ecological restoration methods.  相似文献   

17.
生境是植物生长的具体环境,而群落环境是有机体和生境共同作用的结果。关于岩溶地区植物对不同生境的利用已成为近年来研究的热点。文中系统地总结了岩溶地区小生境类型特征、不同石漠化等级、坡位等因素对自然植被群落分布特征的影响,结合前人研究成果进一步分析了岩溶地区不同生境条件、坡位以及石漠化等级下自然植被群落结构、优势种、物种多样性、生物量以及生活型谱结构的差异,以期为岩溶地区植被与生境耦合程度以及不同生境下植被资源的配置提供理论参考,对岩溶生态环境保护、石漠化防治和石漠化地区植被恢复具有重要意义。  相似文献   

18.
在全面路线踏查的基础上进行典型人工群落样地调查,结果表明:梧桐山人工群落主要有台湾相思群系、大叶相思群系、马占相思群系、木荷+油茶群系等;物种组成共有135种54科109属,并以双子叶植物为主,乔木、灌木性植物种类相对草本和藤本状植物较丰富;各群系物种多样性均表现为灌木层〉乔木层,且乔、灌木层的物种多样性总体上以木荷油茶群系为最高,其次为台湾相思群系,而马占相思群系和大叶相思群系为较低。建议遵循地带性群落演替规律并结合景观生态学、森林生态美学等进行阶段性的人工补植主要乡土树种,起到改善小气候环境并促进生态功能强、观赏价值高和发展稳定的城市森林群落形成。  相似文献   

19.
霍妍  郑云龙 《防护林科技》2013,(1):15-17,20
以大黑山水土保持生态修复工程示范区为研究区域,运用典型植物群落物种组成和群落物种多样性指数方法,对大黑山水土保持生态修复区典型植物群落物种多样性变化特征进行了研究,结果表明,生态修复区内天然次生林植物群落形成了乔灌草相结合的稳定的植物群落结构。人工林植物群落按生长型可以划为明显的乔木层和草本层2层群落结构类型;典型植物群落物种多样性指数的排序为:蒙古栎+蒙椴植物群落(Ⅱ)>山杏+黄榆植物群落(Ⅰ)>蒙古栎植物群落(Ⅲ)>油松+山杏混交植物群落(Ⅴ)>油松纯林植物群落(Ⅳ)>油松+沙棘混交植物群落(Ⅵ)>油松疏林植物群落(Ⅶ)。天然次生林植物群落的物种多样性要大于人工林植物群落。天然次生林植物群落由于远离人类活动区,长期以来受人为干扰较小,逐渐形成了相对比较发达的草本层植物群落。  相似文献   

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