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陕北林地啮齿动物群落结构研究 总被引:5,自引:0,他引:5
草免和鼢鼠的优势度从北向南依次降低,而松鼠和黄鼠依次增加,其余种类表现为中间小,两边大。退耕群落中草免、鼢鼠、跳鼠、田鼠、沙鼠和鼠免的优势度高于荒坡群落,而松鼠和黄鼠的优势度退耕群落低于荒坡群落。在吴旗群落中危害刺槐的关键种是中华鼢鼠,对油松和侧柏幼林造成严重危害的是草免。在退耕群落中对林木造成危害的主要是鼢鼠和草免。鼢鼠、松鼠、黄鼠和鼠免的生态位宽度以吴旗风沙区群落一退耕群落一黄土丘陵灌木疏林群落依次缩小。鼢鼠在桥山群落中与各种啮齿动物均有很高的相似性,而在桥北群落中,与其它种类的相似性比例较小。在灌木疏林群落中,鼢鼠与其它种类的相似性大于退耕群落。从主成分群落排序分析,鼢鼠在吴旗风沙区群落中与其它种类的相似性较大,而在退耕群落中的最小。 相似文献
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啮齿动物是哺乳动物中种类最多、数量最多、分布最广的一个类群。在自然界中啮齿动物是一些食肉动物的主要食物来源,是陆地上许多类型生态系统中食物链的重要环节。近年来,国内外对啮齿类群落的研究已有很多报道(张知彬等,2001;武晓东等,1999;2000;杨扬等,2008;周旭东等,2004;Aragon et al.,2009;Courtalon et al.,2010;Tibault etal.,2010)。组成群落的各个物种随气候、小生境和食物的变化,它们种群数量和生活史性状等各因子便会变化。由此群落的物种组成、空间结构、多样性和种间关系等,也随时间而变化(曾宗永,1994)。 相似文献
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沈阳东陵区油松栎林群落特征及物种多样性研究 总被引:1,自引:0,他引:1
以沈阳市东陵区油松栎林群落为对象,分析了群落特征,结果表明,油松栎林群落共有种子植物161种,分属49科121属,区系组成丰富。在植物区系地理成分上,种的分布类型以温带性质居多,共143种,占总种数的88.82%,表明了群落植物区系组成的温带亲缘关系;在群落结构上,油松栎林群落以地面芽植物最多,占36.0%;群落可分为乔木层、灌木层和草本层3个层次;种间联结性以山里红与黄波罗呈显著正关联外,其他种间联结性都较低。群落木本植物科-属-种组成多样性大小顺序为属-种多样性>科-属多样性>科-种多样性。 相似文献
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为了明确西华镇草原啮齿动物群落特征,本研究于2022年5-8月,应用夹夜法(每月1次)调查了该区的鼠密度及其数量配置,并研究了该区啮齿动物群落的多样性特征和繁殖特征。结果表明,在不同月份,啮齿动物群落密度均大于5%,属中等偏重危害程度,其群落结构为长尾仓鼠(占比最大)+朝鲜姬鼠+黑线姬鼠;整体上看,西华镇草原啮齿动物群落的多样性指数随时间推移(5-8月)逐步升高;在调查期间,该区啮齿动物群落的繁殖能力较强,不同鼠种的性比均小于1(北社鼠除外),说明雄性的活动量大于雌性。本研究为科学制定区域性综合防控策略,实现对草原鼠害的高效、安全防控提供了基础依据。 相似文献
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在汕头市中小水库库区范围内的水源涵养林中,选择黎蒴栲林、鸭脚木林、山杜英林3个乡土阔叶树种群落,对群落物种多样性、自然更新情况、群落稳定性进行测定分析,结果表明:3个群落的乔木树种多样性表现为山杜英林〉鸭脚木林〉黎蒴栲林,而黎蒴栲林和山杜英林的相对稳定性较高,其物种多样性和稳定性没有出现明显的正相关。3个群落的多样性、稳定性受制于各自建群种的生物学特性及特定的生境条件,并与人为的干扰强度有关。 相似文献
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2006年6~7月对清西陵不同林型土壤动物群落进行了调查,共获得了土壤动物1461个,隶属8个纲18类(目).其中,其中,山杨林优势类群为弹尾目和蜱螨目,针阔混交林优势类群为弹尾目和双翅目,油松林优势类群为弹尾目、蜱螨目、小杆目和鞘翅目.物种数与个体数变化规律表现为山杨林>针阔混交林>油松林,H'和E的变化规律表现为针阔混交林>油松林>山杨林. 相似文献
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STUDYAREAThefieldinvestigationofsmallrodentcommunitywasconductedinLiangshuiReservefromJunel0t0Julyl8,l992.LiangshuiReserve(El28o53'2OH,N47oI0,50H)locatedinDailingDistrict,YichunCity.Sixforestcut-overareaswithdifferentages(lyear,5years,l0years,l5years,2Oyearsand28years)wereselected.Inthecentreofeacharea,a2.5hm2sam-plesitewasmarkedout.Thetrappingdaymethodwasused.Fourtytrapswereplacedineachsampleareafortwo24-hourcyclesandwereexaminedonetimein24hours.Thebaitwasfreshpineseeds.Theseclear… 相似文献
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巢湖流域生态林建设的重点与措施 总被引:3,自引:0,他引:3
阐述了巢湖流域生态环境的现状,面对植被破坏严重、生物多样性锐减、水土流失加剧、生态系统生产力低等问题,提出了巢湖流域生态林业建设应以水土保持林、水源涵养林、农田防护林、沿岸防浪林、湿地生态保护系统等工程为主,以及应采取的相应措施. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(3):236-243
Abstract In this study, 236 regeneration areas (mostly clear-cuts) in southern Norway were selected by random stratified selection: 118 of the study units were cut before and 118 after the introduction of forest certification in 1998. The degree of compliance with biodiversity measures established in the prevailing certification standard (ISO 14001 and the Norwegian standard “Living Forests”) was compared in a field study, and the differences were analysed. In some aspects, a clear difference could be seen, most clearly in an increasing number of green retention trees and an increasing mean width of buffer-strips left along rivers, bogs and lakes in the postcertification units compared with the precertification units. Even though there was a significant increase in the mean number of retention trees, as much as 21% of the postcertification regeneration areas still did not have sufficient retention trees to comply with the certification standard and 41% had either too few retention trees or too few spruce trees according to the standard. Concerning the management of small swamp forests, and the damage done to terrain and prelogging coarse dead wood by off-road transport, little improvement was seen. The discussion examines whether it is probable that the changes seen are a result of forest certification in Norway. 相似文献
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Md. Habibur Rahman Md. Abu Sayed Arfin Khan Bishwajit Roy Most. Jannatul Fardusi 《林业研究》2011,22(4):551-559
A study was conducted at two-biodiversity conservation areas of Northeastern Bangladesh (a part of Sylhet Forest Division)
to assess the species composition, diversity and density of natural regeneration of tree species both indigenous and exotic
species. Data were collected by stratified random quadrate method during January 2010 to July 2010. Totally 200 circular plots
of 2 m×2 m in size had 5 different habitat types of plants namely; forest, roadside, homestead (surrounding forest dwellers
house), fallow land and others (canals, streams and tea gardens side), which included a total of 55 regenerating species belonging
to 28 families. Meliaceae is the dominant family and shows the highest family importance value (26.3), having six species,
followed by Moraceae (24.24). Among the five habitat types, forest (43 species) possess the highest number of species, followed
by roadside (23 species). Total 15 exotic species among 9 families and 40 indigenous species with 24 families were recorded.
For exotic species, Tectona grandis possess the highest relative density (11.7%) and relative frequency (10.5%); Senna siamea had highest relative abundance (7.83%). In case of indigenous species, Chickrassia tabularis possess the highest relative density (4.23%) and relative frequency (4%); Dipterocarpus turbinatus had the highest relative abundance (3.92%). Tectona grandis (29.66) and Chickrassia tabularis (10.8) had the highest IVI for exotic and indigenous species respectively. Different diversity indices such as Shanon-Winner
diversity index, species diversity index, species richness index, species evenness index, Simpson index and species dominance
index, etc. were applied to quantify definite diversity. The regeneration of species associated with low levels of disturbance
was in the exotic species. Study suggests that proper protection from human disturbances and scientific management of natural
regeneration of two-study forests may lead a rich biodiversity site in the country. 相似文献
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Community structure and biodiversity in plantations and natural forests of seabuckthorn in southern Ningxia, China 总被引:1,自引:0,他引:1
Suo Li You-qing Luo Jian Wu Shi-xiang Zong Guo-long Yao Yuan Li Yuan-mei Liu Yan-ru Zhang 《中国林学(英文版)》2009,11(1):49-54
Two types of sampling plots of seabuckthorn (Hippophae rhamnoides) communities were investigated in Pengyang County of Ningxia region by a typical sampling method to study the characteristics of community structure and biodiversity. Composition and dominant species of each community were analyzed by the importance value of species as an index. The number of individuals and the importance value, as well as Sorensen’s similarity coefficient, Shannon-Wiener diversity index, Pielou’s evenness index and Simpson’s dominance index, were used as indices to compare characteristics of community structure, similarity and biodiversity between plantations and natural forests of seabuckthorn. The results indicate that the importance values of species of natural seabuckthorn communities were dispersed and the difference between dominant species was not statistically significant. Diversity indices of natural seabuckthorn communities reflected by species richness and evenness were higher than that of plantations. Com-munity structure of natural seabuckthorn forests is more complex. We propose that natural forest can be used as sample to guide se-lection of plant species in silviculture in order to improve biodiversity of plantation. 相似文献