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1.
在深圳市红树林主要分布区设置8个调查样地, 以调查深圳市红树林典型群落的物种组成和生物多样性特征。结果表明: (1)秋茄为深圳市天然红树林的建群种或优势物种; 白骨壤及海漆是天然红树林的重要组成物种; 海桑及无瓣海桑是人工林的主要组成物种; 桐花树及老鼠簕是林下灌木层以及低发展程度的红树林群落的主要组成物种。(2)海桑、无瓣海桑、海漆及白骨壤等真红树植物丰富了以秋茄为建群种、优势种或伴生种的深圳市红树林的物种种类、垂直结构和径级结构, 从而提高了红树林的物种多样性和结构多样性, 使林分更加稳定性。在对红树林进行质量提升或营建红树林人工林时, 可以通过增加本土红树植物的种类和提高林分混交程度和结构多样性, 来提高红树林的生态稳定性和景观观赏价值。  相似文献   

2.
五台山林区典型人工林群落物种多样性研究   总被引:36,自引:4,他引:32  
对山西五台山林区4种典型人工林群落物种多样性特征进行了定量研究,结果表明: 1 4种人工林群落灌木层和草本层的Simpson指数 D 和Shannon-Wienner指数 H′ 差异不显著,物种丰富度指数和均匀度指数 Jsw 差异显著,均匀度指数 Ea 差异极显著,草本层发育明显好于灌木层; 2 各人工群落尚处于演替初期阶段,林下植被发育常以禾本科阳生性植物为主; 3 对4种人工林群落灌草层物种多样性显著性检验结果显示,在灌草层物种多样性特征上,油松林与桦木林、山杨林多样性差异显著 P<0.05 ,其它群落差异不显著.山杨林物种多样性程度较高,油松林最差; 4 不同人工林群落物种总体多样性特征分析表明,桦木和山杨人工林群落总体α多样性与油松林差异显著,且多样性较大,阔叶林更有利于林下植被的发育和更新; 5 对人工生态系统物种多样性研究是退耕还林、天然林保护等生态环境工程的延伸,对于植被恢复后的生物学效果评价有重要意义.  相似文献   

3.
在珠海市鹤洲北、横琴岛设置不同的样地对2种人工红树林与2种天然红树林进行群落调查, 分析比较人工林与天然林群落的物种数量、群落优势度、物种多样性和群落空间结构等特征差异, 以期为指导红树林的人工恢复营造提供科学依据。研究表明: 1)无瓣海桑人工林群落的结构组成简单、空间层次分布明显、林下植被主要为老鼠簕; 2)秋茄人工林和天然老鼠簕群落物种组成相对丰富、植物密集、数量众多、竞争激烈; 3)天然桐花林群落则与老鼠簕形成了共优群落; 4)物种多样性综合指数的排序为: 天然老鼠簕群落>天然桐花树群落群落>秋茄人工林>无瓣海桑人工林; 5)在红树林的恢复重建中, 可以考虑乡土种与外来种相结合、通过人工的方式增加群落的物种多样性, 使群落层次更加丰富。  相似文献   

4.
以我国雷州半岛红树林为调查与研究对象, 采用样方调查方法对红树林区系组成、群落结构和分布特征开展调查分析。调查结果表明: 雷州半岛红树林的群落可分为24个类型, 其中白骨壤群落面积占比高达60.55%, 占有绝对优势; 雷州半岛红树林包括真红树植物8科13种, 占全国真红树植物物种的50%, 半红树植物8科10种, 占全国半红树植物物种的83.33%; Shannon—Wiener多样性指数为0.09—1.08, 部分研究区域之间数值差异较大; 从向陆林缘至向海林缘, 物种多样性沿潮间带的变化趋势比较一致, 为高潮间带>中潮间带>低潮间带; 白骨壤为雷州半岛重要的优势种, 在高、中和低潮间带均有分布, 聚集分布为高潮间带<中潮间带<低潮间带; 与2008年雷州半岛国家“908”专项红树林调查结果相比, 该地区所记录的红树物种由14种增加到了23种, 受2008年寒害所影响而枯死的红海榄又逐渐恢复; 附城镇1995年引进无瓣海桑, 与乡土种白骨壤、秋茄一起成为当地的优势种, 说明无瓣海桑的引进对于当地红树林群落恢复具有一定的促进作用。虽然雷州半岛物种组成较为丰富, 但是红树林群落结构仍然不够合理, 对残次天然纯林进行改造和人工多物种造林, 是日后雷州半岛红树林群落恢复和重建的重要方向; 同时也要加强乡土红树植物物种恢复, 维持雷州半岛红树林生态系统物种多样性与生态平衡。  相似文献   

5.
退化土地植被恢复群落物种多样性与生物量分配格局   总被引:12,自引:0,他引:12  
研究了湘西北女儿寨小流域7种典型植被恢复群落生物量的空间分配格局、物种多样性特征及其相互关系。结果表明:1)润楠次生林乔木层生物量最高,马尾松天然林灌木层生物量最大,油桐人工林草本层生物量最高,乔木层最低,毛竹-杉木林灌木层与草本层生物量最小,群落总生物量以马尾松天然林群落最高,荒草灌丛群落最低。2)乔木层物种以润楠次生林最丰富,多样性指数最高,物种分布最均匀;灌木层物种丰富度以毛竹-杉木混交林最高,油桐人工林多样性与均匀度指数最大,优势度最小,荒草灌丛群落的物种丰富度、多样性及均匀度最低;草本层物种丰富度以油桐人工林最高,马尾松天然林最低,杉木人工林草本层多样性指数与均匀度指数最大,润楠次生林优势度最高;群落总体物种丰富度以油桐人工林最高,润楠次生林群落的多样性指数最高,种群分布最均匀,荒草灌丛群落的多样性、均匀度与优势度都最低。3)女儿寨小流域退化土地物种丰富度与群落生物量之间的关系可用"S"曲线较好地描述,双曲线能较好地描述群落多样性指数、群落均匀度指数与生物量之间的关系,而生态优势度与生物量之间为非性线关系。  相似文献   

6.
对红树植物无瓣海桑、海桑、秋茄3种人工林群落动态及物种多样性特征的系统研究结果表明,无瓣海桑群落和海桑群落的乔木层明显分为上层和中层两个亚层,上层木为无瓣海桑或海桑,中层木主要为秋茄和桐花树;秋茄群落的乔木层为单一层次,基本由秋茄组成.在无瓣海桑群落和海桑群落中,优势种群无瓣海桑或海桑仅有高龄级个体存在,未出现自然更新现象;秋茄和桐花树为旺盛增长种群,有可能成为优势种群,表明无瓣海桑和海桑为先锋造林树种,在裸滩种植可以促进其它红树植物的天然定居生长;在秋茄群落中,秋茄为旺盛增长种群,能够自然:更新演替,桐花树和海莲属初生增长种群.无瓣海桑群落和海桑群落的物种组成和物种多样性指标较接近,基本包含秋茄群落中的主要物种秋茄、桐花和海莲。表明无瓣海桑和海桑能与这些物种协调共生,同时种植无瓣海桑或海桑可以形成多样化的红树林群落;无瓣海桑群落和海桑群落在形成初期,种植密度较大时,物种多样性较高;密度相近时。形成初期随林龄的增加。其物种多样性略有提高.  相似文献   

7.
广西的红树林   总被引:8,自引:0,他引:8  
林鹏  胡继添   《广西植物》1983,(2):95-102
本文主要讨论广西沿海的红树林的植物种类成分、外貌、适应形态学特点、群落类型和演替规律,以及生产管理问题。 该地区的红树植物种类计有8科、12属、12种,以红树科植物占优势。群落类型有:白骨壤群落、桐花树群落、秋茄-桐花树群落、红海榄群落、木榄群落、木榄-桐花树群落、桐花树-海漆稀树群落和红海榄+秋茄-桐花树群落等。  相似文献   

8.
光皮桦天然林群落结构及物种多样性分析   总被引:5,自引:0,他引:5  
对福建省光皮桦(Betula luminifera H.Winkl)天然林群落结构和物种多样性进行了调查分析。结果表明,光皮桦天然林群落的物种多样性丰富,与光皮桦混生的植物种类有46科78属117种。9个光皮桦天然林群落乔木层中,武平县梁野山自然保护区的Simpson多样性指数最高,邵武卫闽的最低。较原生的森林群落中,以壳斗科植物为基本建群种,物种多样性较丰富,光皮桦重要值较低。在原生森林遭到破坏后的演替过程中,光皮桦重要值增高,成为落叶阔叶林类型之一。光皮桦天然林渐危的主要原因是人为破坏,应加强现有天然林资源的保护、注重遗传资源的收集和保存以及人工林资源的培育。  相似文献   

9.
珠海市淇澳岛红树林群落组成初步研究   总被引:11,自引:0,他引:11  
本文研究了珠海市淇澳岛红树林的组成、群落类型、群落结构外貌、生态序列及红树林内的主要动物种类.初步调查结果显示:该地区有红树植物7科9种,半红树5科6种,红树林伴生植物4科8种,脊椎动物中鸟类10目20科46种.淇澳岛红树林群落类型主要有:秋茄-桐花树-老鼠筋群落、桐花树-芦苇群落、老鼠筋群落、无瓣海桑群落、木榄-银叶树群落.本文还针对珠海淇澳岛红树林湿地资源现状提出可持续发展建议.  相似文献   

10.
为研究广西北部湾茅尾海自然保护区海岛红树林群落的空间点格局和演替规律,在典型红树林海岛设置调查样地,以样地内的桐花树(Aegiceras corniculatum)、秋茄(Kandelia obovata)、白骨壤(Avicennia marina)等红树植物为研究对象,构建单变量函数的完全空间随机模型、异质泊松模型与双变量函数的环形转变模型,分析3种红树林种群的结构特征、空间格局及种内种间关联性。结果发现:(1)桐花树种群的小树和中树的个体数目较多,种群年龄结构呈金字塔型,种群处于增长状态;秋茄种群的中树个体数目较多,种群结构呈钟型,种群数量处于稳定状态;白骨壤个体数相对较少,且幼树较少老树较多,种群更新受阻,种群结构呈纺锤型,属于衰退型种群。(2)红树林群落整体上呈现出空间集聚的分布特征,从不同种群的集聚程度来看:桐花树>白骨壤>秋茄。(3)随着空间尺度的增大,红树林群落在空间分布上依次表现出聚集、随机和均匀3种特征。(4)桐花树与秋茄、白骨壤的种间关系随着尺度增加均表现为空间无关联性-空间负关联性-空间无关联性的演变特征,秋茄与白骨壤的种间关系则为全尺度的空间无关联性。(5)桐花树种内不同龄级之间存在空间正关联性、空间无关联性和空间负关联性,秋茄种内不同龄级之间均表现出空间无联性,白骨壤种群则在不同龄级之间均出现空间正关联性。(6)红树植物种群的空间格局受到自身繁殖特性、生境异质性、种内和种间竞争、病虫害等多种因素的影响。红树林人工种植和恢复需要结合沿海地区的自然生态条件,按照红树林种群的适应形态学特点、群落类型和自然演替规律,种植乡土红树植物,适当引进外来物种,研制出近似天然的人工红树林林分结构,提高群落的生物多样性和群落稳定性,发挥红树林湿地生态系统的生态环境效应。  相似文献   

11.
Local fisherfolk and fishpond owners have been practicing “restoration” of mangrove forests in some parts of the Philippines for decades, well before governments and non‐government organizations began to promote the activity as a conservation tool. This paper examines ecological characteristics of these mangrove plantations and compares them to natural mangroves in the same areas. Mangrove planters were interviewed and plantation and natural mangrove forests were surveyed to measure forest structure, composition and regeneration. Compared with natural forests, mangrove plantations were characterized by high densities of small stems, shorter and narrower canopies, and fewer species. For both economic and ecological reasons, the vast majority of people dispersed and planted only Rhizophora mucronata/stylosa and, furthermore, they often thinned other species out of planted areas. There was remarkably little subsequent recruitment of other, nonplanted mangrove species into plantations up to 50 and 60 years of age. This pattern held across a diversity of sites, including plantations that had not been selectively cut or weeded. Important ecological and economic benefits result from local mangrove planting, but catalyzing diverse forest regeneration—at least in the short to medium term—is not one of them. The lesson: if you want to restore diverse mangrove forests, you have to plant diverse mangrove forests.  相似文献   

12.
香港三种人工林下植物多样性的调查   总被引:23,自引:0,他引:23  
报道了作者于1995年6月至19%年1月期间对香港3种人工林-红胶木林、相思树林、荷树及其混交林林下植物区系调查的初步结果。在10个面积为200-400m2的人工林样方中,共记载了184种非栽培的植物种类,它们分属于70个科139属,其中42%的种类是树木,约占香港树木区系的20%。最常见的植物种类通常具有可以被鸟类传播的小型浆果或核果,它们也是天然次生林中的常见种。这些人工林样方的树木多样性(Shannon指数)在0-2.66之间,随着人工林的年龄增长呈增加的趋势。人工林在加速森林植被的恢复和促进退化地区生物多样性的发展中具有重要的作用,特别是植物种源严重贫乏地区森林植被恢复的重要手段。在营造速生人工林时,适当引入鸟播的野生树种,可加速人工林的自然演替速度和提高人工林的生态效益。  相似文献   

13.
合理的森林恢复方式能提高植物多样性,进而提高生态系统服务功能.在我国南方红壤区研究了3种典型森林恢复方式(引进种恢复的湿地松(Pinus elliottii)人工林本地种恢复的马尾松(Pinus massoniana)人工林和自然恢复的天然次生林)的植物区系构成和植物群落多样性.结果表明:(1)湿地松人工林有155种植物,隶属66科118属,马尾松人工林有137种植物,隶属59科97属;天然次生林有226种植物,隶属86科160属,3种森林恢复方式的乔木层、灌木层和草本层的优势科属明显不同,马尾松人工林的优势物种和天然次生林更相似;(2)天然次生林的植物区系基本构成、植物区系类型种类高于马尾松人工林和湿地松人工林,并且天然次生林的温带成分比例高于湿地松人工林;(3)恢复方式对植物群落的多样性指数有显著影响,天然次生林的物种丰富度、辛普森指数明显高于马尾松人工林和湿地松人工林,两种人工林之间差异不显著;(4)3种森林恢复方式的植物群落结构存在显著差异,相比湿地松人工林,马尾松人工林的植物群落组成与天然次生林更相似.总之,自然恢复的天然次生林植物群落多样性高于人工恢复的马尾松人工林和湿地松人工林,本地种马尾松人工林在维持区域植物群落结构功能上优于引进种湿地松人工林.  相似文献   

14.
To examine the natural colonisation of native mangrove species into remediated exotic mangrove stands in Leizhou Bay, South China, we compared soil physical–chemical properties, community structure and recruitments of barren mangrove areas, native mangrove species plantations, and exotic mangrove species—Sonneratia apetala Buch.Ham—between plantations and natural forest. We found that severely degraded mangrove stands could not regenerate naturally without human intervention due to severely altered local environments, whereas some native species had been recruited into the 4–10 year S. apetala plantations. In the first 10 years, the exotic species S. apetala grew better than native species such as Rhizophora stylosa Griff and Kandelia candel (Linn.) Druce. The mangrove plantation gradually affected soil physical and chemical properties during its recovery. The exotic S. apetala was more competitive than native species and its plantation was able to restore soil organic matter in about 14 years. Thus, S. apetala can be considered as a pioneer species to improve degraded habitats to facilitate recolonisation by native mangrove species. However, removal to control proliferation may be needed at late stages to facilitate growth of native species. To ensure sustainability of mangroves in South China, the existing mangrove wetlands must be managed as an ecosystem, with long-term scientific monitoring program in place.  相似文献   

15.
In the face of the continuing destruction of tropical rainforests, a major challenge is to understand the consequences of these habitat changes for biodiversity and the time scale at which biodiversity can recover after such disturbances. In this study, we assessed the patterns in communities of birds among forests of varying age consisting of clear-cuts of former coniferous plantations, selectively logged compartments and primary forests in Kibale National Park, Uganda. Birds were surveyed by 10-minute point counts at 174 randomly located points in nine forest areas during September–October 2011. A total of 2 688 birds representing 115 species were recorded. The species density, diversity and dominance of all birds, and dominance of forest specialists showed no differences between forest areas, whereas the species density and diversity of forest specialists differed significantly between forest areas. The composition of communities of all birds and of forest specialists varied significantly among the forest areas. Our results show that even after 19 and 43 years, respectively, communities of birds in clear-cuts of former coniferous plantations and selectively logged forests have not fully recovered from the disturbances of logging, highlighting the need to preserve primary forests for conservation of birds.  相似文献   

16.
Human disturbance threatens and modifies forest ecosystems worldwide. Previous studies have investigated the effects of human impact on local bird communities in disturbed forests, but we still lack information on how bird species richness and ecological processes respond to different forest modifications present at a landscape scale. In a heterogeneous South African landscape, we chose six types of indigenous scarp forest, differing in the intensity of human disturbance: continuous natural forests and natural forest fragments in nature reserves, forest fragments in eucalyptus plantations, fragments in the agricultural matrix, forest gardens and secondary forests in game reserves. In 36 study sites, we investigated the bird community using point counts and observed the seed removal of birds at the native tree species Celtis africana. Species richness did not differ among the forest types, but abundance varied significantly with most birds observed in fragments in the agricultural matrix, forest gardens, and secondary forests. The higher bird abundance in these forests was mainly due to forest generalists, shrubland and open country species whereas forest specialists were rarely present. Changes in species composition were also confirmed by multivariate analysis which clearly separated bird communities by forest type. Frugivore abundance in C. africana was highest in natural forest fragments, fragments in the agricultural matrix, forest gardens and secondary forests. The same trend was found for the estimated total number of fruits removed per C. africana tree, though the differences among forest types were not significant. Consequently, modified forests seem to maintain important ecological functions as they provide food sources for generalist species which may, due to their mobility, enhance natural plant regeneration. However, we could show that protected forest habitats are important refugees for specialist species sensitive to human disturbance.  相似文献   

17.
Abstract We examined the potential of forest plantations to support communities of forest‐using insects when planted into an area with greatly reduced native forest cover. We surveyed the insect fauna of Eucalyptus globulus (Myrtaceae) plantations and native Eucalyptus marginata dominated remnant woodland in south‐western Australia, comparing edge to interior habitats, and plantations surrounded by a pastoral matrix to plantations adjacent to native remnants. We also surveyed insects in open pasture. Analyses focused on three major insect orders: Coleoptera, Lepidoptera and Hymenoptera. Plantations were found to support many forest‐using insect species, but the fauna had an overall composition that was distinct from the remnant forest. The pasture fauna had more in common with plantations than forest remnants. Insect communities of plantations were different from native forest both because fewer insect species were present, and because they had a few more abundant insect species. Some of the dominant species in plantations were known forestry pests. One pest species (Gonipterus scutellatus) was also very abundant in remnant forest, although it was only recently first recorded in Western Australia. It may be that plantation forestry provided an ecological bridge that facilitated invasion of the native forest by this nonendemic pest species. Plantation communities had more leaf‐feeding moths and beetles than remnant forests. Plantations also had fewer ants, bees, evanioid wasps and predatory canopy beetles than remnants, but predatory beetles were more common in the understory of plantations than remnants. Use of broad spectrum insecticides in plantations might limit the ability of these natural enemies to regulate herbivore populations. There were only weak indications of differences in composition of the fauna at habitat edges and no consistent differences between the fauna of plantations adjacent to remnant vegetation and those surrounded by agriculture, suggesting that there is little scope for managing biodiversity outcomes by choosing different edge to interior ratios or by locating plantations near or far from remnants.  相似文献   

18.
Commercial plantations and alien tree invasions often have substantial negative impacts on local biodiversity. The effect of plantations on faunal communities in the fire‐adapted fynbos vegetation of the Cape Floristic Region biodiversity hotspot is not yet well quantified. We studied small mammal community structure in alien Pinus radiata plantations and adjacent fynbos regenerating after clear‐felling of plantations on the Cape Peninsula, South Africa. Small mammal sampling over 1,800 trap‐nights resulted in 480 captures of 345 individuals (excluding recaptures) representing six species. Significantly more species, individuals (12 X) and biomasses (29 X) of small mammals occurred on recovering fynbos sites compared to plantations. This was commensurate with a higher diversity of plant growth forms, vegetation densities and live vegetation biomass. Only one small mammal species, the pygmy mouse (Mus minutoides), was consistently trapped within plantations. Fynbos sites were dominated by three small mammal species that are ecological generalists and early successional pioneer species, rendering the recovering fynbos slightly depauperate in terms of species richness and evenness relative to other studies done in pristine fynbos. We make three recommendations for forestry that would facilitate the restoration of more diverse natural plant communities and progressively more diverse and dynamic small mammal assemblages in a key biodiversity hotspot.  相似文献   

19.
海堤对广西沿海红树林的数量、群落特征和恢复的影响   总被引:1,自引:0,他引:1  
广西大陆海岸线的63%为海堤,海堤数量达498个.海堤建立毁灭了原生红树林,现余5654hm2,其中约85%为堤前红树林.海堤阻截了红树林滩涂的自然海岸地貌,结果是红海榄和木榄已很少,榄李濒危,角果木已消失,海漆和陆岸种类只能沿海堤坡面生长,而先锋红树植物白骨壤和桐花树成为现有红树林的优势种.堤前红树林的恢复受到海堤维护时强烈的人为干扰.堤前滩涂相对于平均海平面的高程较低,不是红树林繁盛的理想滩涂.红树林人工造林的成活率和次生林恢复的速率在很大程度上取决于生境的沉积率.  相似文献   

20.
广东澳头红树植物群落的物种多样性与种群分布格局研究   总被引:18,自引:0,他引:18  
陈桂珠  缪绅裕 《生态学杂志》1994,13(2):34-35,43
广东澳头红树植物群落的物种多样性与种群分布格局研究陈桂珠,缪绅裕(中山大学环科所,中山大学生物系,广州510275)SpeciesDiversityandPopulationDistributionPatternofMangroveCommunity...  相似文献   

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