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1.
英罗港红树林土壤粒径分布的分形特征   总被引:25,自引:1,他引:24  
应用分形理论分析了英罗港红树林土壤粒径分布的分形特征。结果表明,红树林土壤的分形维数为2.6837-2.8834,不同质地土壤的分形维数呈现砂壤土<轻壤土<中壤土<重壤土<轻粘土的规律,外滩红树林土壤的分形维数低于中滩和内滩。土壤分形维数与其盐分和有机质含量呈显著正相关。群落类型、土壤质地、滩位、含盐量、有机质含量等是影响英罗港红树林土壤分形维数的主要因子。  相似文献   

2.
广西英罗港红树林潮沟鱼类多样性季节动态研究   总被引:11,自引:0,他引:11  
于1999年分4个季节来采用拦网的方法对广西英罗港红树林潮沟水中鱼类的多样性进行了研究,共发现鱼类54种,隶属于29种44属,季度出现频数F=1~4的鱼类种数分别为27、8、11和8种,各季的优势种明显,但不同季节最大优势种不同,分别为:春季、斑Ji(Clupanodon punctatus);夏季,前鳞骨鲻(Osteomugil ophuyseni);秋季,眶棘双边鱼(Ambassis gymnocephalus);冬季,鹿斑Fu(Leiognathus ruconius),这些鱼类以暖水性种占绝对优势,在生态类型上以底层种类较多,各季节出现鱼类种数分别为:春季30种、夏季30种,秋季26种,冬种22种,夏季与秋季共有种最多,有20个种,这两季节间的相似性指数也最大,达55.6%,多样性指数D、H′、J值均以秋季最高,相对于林外水域,红树林潮沟鱼类群落的鱼类种数及3个指数均较高,跟热带红树林区相比,广西英罗港红树林潮沟鱼类群落的多样性低。  相似文献   

3.
海南清澜港红树林滩涂大型底栖动物初步研究   总被引:5,自引:0,他引:5  
对海南清澜港红树林滩涂大型底栖动物进行了定性及定量调查,记录到大型底栖动物45种,隶属于4个门,26个科。其中软体动物31种,占记录到物种数的689%;甲壳动物10种,占记录到物种数的222%。优势种是珠带拟蟹手螺(CerithideacingulataGmelin)、古氏滩栖螺(BatilariacumingiCrose)、中国紫蛤(HiatulachinensisMorch)及奥莱彩螺(ClithonoualaniensisLeson)。大型底栖动物的生物量平均1985g/m2、栖息密度3524个/m2。软体动物的生物量占到99%,这可能与取样设在中、低潮区有关。  相似文献   

4.
用扩增片段长度多成性(AFLP,amplified fragment length polymorphism)方法研究了荷木(Schima superba Gardn.et Champ.)和锥栗(Castanopsis chinensisHance.)在3个演替系列群落中的分子变化。研究地点位于广东省鼎湖山。3个群落是针叶林群落、针阔叶混交林群落和常绿阔叶林群落。荷木的AFLP分析结果表明,4组  相似文献   

5.
中药材贮藏期昆虫群落结构的研究   总被引:16,自引:0,他引:16  
根据对湖北省17个市县中药材仓库的调查,共发现湖北省中药材贮藏期昆虫(含蜱螨)123种,隶属于2纲10目49科。通过对各地昆虫群落结构的分析,明确了构成中药材贮藏期昆虫群落的主要类群为鞘翅目昆虫,占昆虫群落全部物种数的72.86±7.63%,全省中药材贮藏期鞘翅目昆虫共85种,占全部昆虫种类的69.11%。本文对各地昆虫群落的优势种群进行了分析,结果表明构成中药材贮藏期昆虫群落的优势种为烟草甲Lasiodermaserricurne(Fabricius),药材甲stegobiumpaniceum(L.),赤拟谷盗TriboliumferrugineumFabricius,咖啡豆象Araecerusfasciculatus(DeGeer)和印度谷螟Plodiainterpunctella(Hubner)等,但各地昆虫群落的优势种各有不同。  相似文献   

6.
吕梁山严村低中山区植物群落演替分析   总被引:11,自引:0,他引:11  
采用一次性同时调查的方法获得数据,用数量分类(TWINSPAN)和排序(DCA)研究严村低中山植物群落演替。在黄土弃耕地上群落的演替顺序为:苦苣+狗尾草群落(Comm.Ixeris chinensis ssp.versicolor+Setaria viridis)→蒿类群落(Comm.Artemisia spp.)→野艾蒿+披碱草群落(Comm.Artemisia lavandulaefolia+  相似文献   

7.
哀牢山木果石栎群落优势种的生态位宽度与重叠   总被引:24,自引:0,他引:24  
通过多种方法比较研究了哀牢山木果石栎(Lithocarpus xylocarpus)群落8个优势种的生态位宽度和重叠,结果表明,该群落是以木果石栎、腾冲栲(Castanopsis wattii)、滇木荷(Schima noronhae)和景东石栎(Lithocarpus chintungensis)为优势种的共优群落,它们的生态位宽度值分别为0.8732,0.7856,0.6742和0.5798。  相似文献   

8.
转Bt基因棉田昆虫群落多样性及其影响因素研究   总被引:42,自引:6,他引:36       下载免费PDF全文
崔金杰  夏敬源 《生态学报》2000,20(5):824-829
运用群落生态学的方法,研究了转Bt(Bacillus thuringiensis)基因棉田昆虫群落及害虫和天敌亚群落多样性,对多样性及其主要组成成分-物种数、个体数、均匀度、优势集中性进行了通径分析。试验设3个处理:转基因棉自然控制(全生育期不施用任何农药,简称自控田)、转基因棉综合防治(采取综合防治措施,简称综防田)和常规棉自然控制(常规品种,全生育期不施用任何农药,简称对照田)。结果表明:转基  相似文献   

9.
三峡库区残存的常绿阔叶林及其意义   总被引:5,自引:0,他引:5       下载免费PDF全文
三峡库区世坪森林公园的常绿阔叶林处在中亚热带北部,群落中48.65%的物种具热带性质,35.14%的物种具温带性质;33.78%的物种集中在忍冬科(Caprifoliaceae)、壳斗科(Fagaceae)等7个科,全部38个科中81.58%的科仅有1~2种植物在群落中出现;群落含有具先锋意义的伴生种。这些都反映出该地带的次生常绿阔叶林的一般特点。栲树(Castanopsisfargesi)的重要值在乔木层和灌木层均居第一,特别是在乔木层该值显著高于其它种,说明此处的常绿阔叶林是以栲树为建群种的单优群落,而且栲树种群径级结构符合其正常发育规律,因而群落相对稳定。该群落对于中亚热带地带性植被的生态学和生物多样性的基础研究具有重要意义,对于退化生态系统的恢复和三峡水库的水源涵养具有典范作用。  相似文献   

10.
青州南部山区冬季鸟类群落生态的初步研究   总被引:1,自引:0,他引:1  
青州南部山区冬季鸟类群落生态的初步研究丛建国(山东潍坊教育学院生物系,青州262500)CommunityEcologyofWinterBirdsinSouthernMountoinousDistrictofQingzhou¥CongJoanguo(De-partmentofBiology,WeifangEducationalCollege,ShandongProvince,Qingzhou262500).ChineseJour-nalofEcoloLyy,1993,12(5):52-55。AsurveyonbirdcommunitiesinsouthernmountainousdistanceofQingZhou,ShandongProvince,iscouducted30speciesarefoundand4time;dominantspeciea,Thenumberofspeciesanddensityofbirdcommunityarevariedwithdifferenthabitats,UsingFuzzyanalysismethod,6bird.Communitiesareclassitied  相似文献   

11.
无瓣海桑具有耐贫瘠、生长快等特点,已成为我国东南沿海滩涂主要造林先锋种。然而,作为典型外来物种,无瓣海桑是否具有入侵性也一度引起各界广泛关注。三亚河是我国无瓣海桑引种的最南区域,但目前尚未有对该区无瓣海桑入侵性的报道。本研究利用全面踏查与样地调查相结合的方法,分析了三亚河外来红树植物无瓣海桑的种群动态及扩散特征。结果表明:无瓣海桑在样地群落上层平均密度为4 ind·100 m-2,重要值为41.2%,具有较明显优势,而在群落中下层无其小树和幼苗分布,无瓣海桑种群更新难以维持;群落中、下层红树植物的Shannon指数分别为1.68和1.09,Simpson指数分别为0.78和0.57,物种多样性较高,本地红树植物长势良好,生存空间未受到明显挤占;三亚河亦未见无瓣海桑种群的自然扩散,较高的盐度可能是抑制无瓣海桑种群扩散的关键。鉴于无瓣海桑优良的生长适应能力,可在无淡水汇入的滨海湿地红树林生态工程中作为先锋种进行合理利用,同时对其做好长期监测与定位研究。  相似文献   

12.
Commercial food- and pheromone-baited pitfall traps and pheromone-baited sticky traps were used during 2003 to survey stored-product insect adults in eight participating feed mills in the midwestern United States. Across the eight feed mills, 27 species of beetles (Coleoptera) and three species of moths (Lepidoptera) were captured in commercial traps. The red flour beetle, Tribolium castaneum (Herbst), was the most abundant insect species captured inside the eight mills. The warehouse beetle, Trogoderma variabile (Ballion), was the most abundant insect species outside the mill and in the mill load-out area. The Indianmeal moth, Plodia interpunctella (Hübner), was the most abundant moth species inside the mill and in the mill receiving area. The Simpson's index of species diversity among mills ranged from 0.39 (low diversity) to 0.81 (high diversity). The types of species found among mills were different, as indicated by a Morisita's index of <0.7, for the majority of mills. The differences in the types and numbers of insect species captured inside, outside, in receiving, and in load-out areas could be related to differences in the types of animal feeds produced and the degree of sanitation and pest management practiced.  相似文献   

13.
The aim of the present paper is to provide first information on the mangrove fish community of the tropical fjord-like Golfo Dulce (GD), to study its importance for fish diversity and fisheries in the area and to give preliminary results on its spatial–temporal variation. Eighty-two species belonging to 30 families were identified. More than half of them belonged to the estuarine transient fish group and only 14 species were estuarine resident, highlighting the importance of the Zancudo mangrove as a transition area. The most diverse families were Sciaenidae, Carangidae and Haemulidae for both rainy and dry seasons. As much as 71% of the species captured were of first or second grade economic value and only 11% had no commercial value. Comparing our data with fisheries and scientific surveys inside and outside the gulf suggests the importance of the Zancudo mangrove for regional fisheries and fish diversity. Multidimensional scaling (MDS) indicated gradual changes in the fish community composition from the river mouth to the more internal sampling sites for rainy and dry seasons. Moreover, shifts in abundance and species composition between seasons were observed, mainly an increase in the differences between the boundaries and the central zones of the mangrove. These changes were attributed to the higher salinity differences between sites during the dry season forcing the occasional visitor fish downstream and freshwater fish taxa upstream. While the results contribute to initiatives for participative fisheries management in the region, further studies are needed to analyse the variations in detail.  相似文献   

14.
Understanding the relationships between mangrove forest succession and the functional diversity of mangrove fauna could facilitate the restoration of mangrove ecosystems, which have been severely damaged in recent decades. The current report describes changes in macrobenthic functional diversity in a mangrove chronosequence that included a primary community (unvegetated shoal), an early community (Avicennia marina), a middle community (Aegiceras corniculatum), and a late community (Bruguiera gymnorrhiza?+?Rhizophora stylosa) in Zhanjiang, China. Phytophages were the dominant macrobenthic functional feeding group regardless of mangrove succession stage, sampling season, or macrobenthic faunal parameter (species richness, abundance, and biomass). As mangrove succession progressed, the proportions of macrobenthic species richness, abundance, or biomass represented by omnivores significantly increased (except for biomass and in the late stage; ranged from 0.065 to 0.230 and 0.033 to 0.368, respectively in wet season, and 0.000 to 0.192 and 0.000 to 0.396, respectively in dry season), while the proportions significantly decreased for detritivores during the dry season (ranged from 0.156 to 0.056, 0.107 to 0.019, and 0.066 to 0.005, respectively). Non-metric multi-dimensional scaling and PERMANOVA also indicated that the structure of macrobenthic faunal functional feeding groups was significantly affected by mangrove succession. Further analyses indicated that the changes in the relative dominance among macrobenthic faunal functional feeding groups during mangrove succession were mainly associated with changes in plant density, coverage/canopy density, and total nitrogen content of sediment, i.e., they were mostly associated with changes in food sources. The results increase our understanding of the relationship between benthic functional diversity and mangrove succession and could help guide mangrove restoration in China and around the world.  相似文献   

15.
Joniak  Tomasz  Goł dyn  Ryszard  Kozak  Anna 《Hydrobiologia》2003,496(1-3):311-319
Patterns in composition, abundance and diversity of the annelid fauna (Polychaeta and Oligochaeta) in 22 sandy beaches in Iceland were explored. The effect of exposure on annelid distribution was studied. A total of 5651 annelids were recorded from 160 core samples. Oligochaetes (chiefly Tubificidae) dominated the annelid assemblage whereas polychaetes represented a minor fraction. Polychaetes were relatively more abundant in exposed than in sheltered beaches, contrary to oligochaetes. Meiofaunal polychaete species were also more abundant in exposed than in sheltered beaches. Southwest beaches seemed more diverse in annelid species than northern ones. Annelid diversity did not differ between sheltered and exposed sites, but higher diversity was attained in fine sands at sheltered areas. Cluster analysis revealed large differences between beaches in the annelid community composition. The general patterns found suggest that beach exposure is a major factor conditioning macro- and meiofaunal polychaete and oligochaete distribution along the Icelandic coast.  相似文献   

16.
Questions : How do species diversity, frequency and composition in tussocks differ from those in similar sized plots outside tussocks? Does the extent of the differences depend on community types or environmental conditions? Location : A sub‐alpine grassland in the Swiss National Park. Methods : In each of the two communities (short grass and tall graminoid) differing in species composition, grazing intensity and soil nutrient availability, relevés were made in 40 pairs of small circular plots, with one plot located inside a randomly selected Carex sempervirens tussock and the other outside. Results : We found 92 vascular species, of which 46 had a frequency higher than 5%. Species richness (S), pooled cover, Shannon's diversity (H) and cumulative species number (CS) were higher outside than inside the C. sempervirens tussocks, but evenness (J) was lower. S, H and CS differed more in the tall graminoid community than in the short grass community. However, dissimilarity between the paired relevés inside and outside tussocks did not differ between the two communities. Of the 46 most frequent species, 12 were statistically more and only one less frequent outside than inside the tussocks. Vegetation inside and outside tussocks could be clearly distinguished in the ordination space. Conclusion : Vegetation inside C. sempervirens tussocks is different from that in the surrounding area and represents an impoverished but homogenized version of the surrounding vegetation. Although tussocks of C. sempervirens were systematically avoided by grazers, there is little evidence that tussocks facilitate the species growing inside them.  相似文献   

17.
长白山阔叶红松林昆虫多样性研究   总被引:9,自引:5,他引:4  
通过季节性观察,系统地研究了长白山阔叶红松林昆虫类群及其多样性.结果表明,长白山阔叶红松林已知的森林昆虫26目131科1162属1960种,其中森林害虫11目105科881种、重要森林害虫638种;森林昆虫群落中植食性昆虫类群总数所占比重最大,天敌昆虫群落中以捕食性类群总数所占比重最大.植食类群、寄生性类群和捕食类群全年的均匀度指数分别为0.884、0.830和0.806.各类群问季节变动系数的大小顺序为捕食类群>寄生性类群>植食类群.  相似文献   

18.
为评价围垦促淤工程对南汇东滩湿地大型底栖动物生态学的影响,根据2004年10月和2009年10月对南汇东滩湿地底栖动物的定量定性调查数据,进行对比分析。结果表明:2004年共采集到大型底栖动物32种,其中在经围垦促淤后形成的堤内、堤外两个区域分别采集到底栖动物20种和21种,2009年堤内外分别为9种和19种,共26种;2004年堤内和堤外优势种分别为8种和4种,共有优势种为中华蜾蠃蜚和谭氏泥蟹,2009年堤内优势种仅有摇蚊幼虫1种,堤外有4种,优势种种类组成也发生了很大变化;2004年大型底栖动物的平均丰度和生物量分别为44.15个/m2和38.80 g/m2,2009年为86.76个/m2和1.97g/m2,2009年堤内、堤外的生物量与2004年相比明显降低,丰度变化则相对较小;运用SPSS软件的单因素方差分析、群落聚类和MDS排序对南汇东滩湿地各断面进行群落结构分析,结果表明围垦是大型底栖动物群落结构改变的一个重要因素,围垦造成堤内底栖动物群落结构发生了明显差异,堤外群落结构变化相对较小。大型底栖动物的生物多样性指数(Shannon-Weiner指数H'、Pielou均匀度指数J'、Margalef物种丰富度指数d和Simpson指数D)受到围垦促淤工程的影响均降低,尤其以围垦圈淤的堤内湿地生物多样性指数最低。围垦促淤工程对盐度、潮汐动力、底质特征的改变以及人类活动等因素是影响大型底栖动物群落结构的主要原因,工程结束后的湿地生态修复十分必要。  相似文献   

19.
苜蓿人工草地节肢动物群落的时间格局   总被引:15,自引:4,他引:11  
调查了甘肃省庄浪县苜蓿人工草地节肢动物群落的组成及多样性变化,应用主分量分析和最优分割法对节肢动物群落的时间格局进行了研究。结果表明,苜蓿人工草地节肢动物群落的物种丰富度,多样性和均匀度指标在时间过程中的变化有明显的差异和规律性,6月下旬害虫和天敌的物种丰富度均达到最大值,但天敌的个体数量高峰明显落后于害虫,在时间变化过程中,影响节肢动物群落的主导因素和时间格局分化明显,根据研究结果,将苜蓿人工草地节肢动物群落在时间动态中的变化划分为5月上旬以前,5月中旬-6月上旬,6月中旬-7月中旬,7月中旬以后4个阶段,并结合气候,物候变化,分析了各阶段内主要害虫和天敌的发生特点,提出了害虫的治理对策。  相似文献   

20.
Mangrove bird communities in north Australia comprise relatively few passerine species compared with other arboreal habitats in the region. Mangroves are dominated by a few tree species and there are potentially few resource axes available for partitioning by terrestrial birds. Competition for limited resources is predicted to cause strong niche differentiation and a highly structured, but low diversity, bird assemblage. Using multivariate and bipartite network analyses based on 1771 foraging observations (33% of 5320 behavioral observations), we examined resource partitioning by 20 terrestrial bird species in mangroves of north Australia. The mangrove bird community largely comprised generalist insectivores that partitioned insects by size with moderate‐to‐high interspecific overlap in diet. Gleaning for insects was the most common foraging mode. Few species specialized on nectar. Flowers of one or more mangrove species were available in every month of the year and insect abundance was correlated with flowering peaks. Niche differentiation by birds was determined by food type and foraging mode more than by broad spatial (mangrove zones) or temporal (seasonal) segregation of the use of resources. There was little evidence of bird species saturation or species sorting, suggesting loose species packing and a lesser role than expected for species interactions and interference competition in structuring the bird assemblage in mangroves.  相似文献   

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