首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 312 毫秒
1.
随着城市的快速发展,城市自然生态体系受到人类活动强烈的冲击,城市景观严重破碎化,城市自然保护区也受到城市建设的挤压和干扰而孤岛化,呈割裂的斑块状,生态风险加剧。因此,构建动物廊道成为保护城市自然保护区完整性和连续性的关键。深圳是我国城市化强度较高的地区,该城市的自然保护区正受到城市建设的强烈挤压与冲击,城市自然保护区受人为干扰而割裂,生境遭到不同程度的破坏,生物多样性退化的形势极其严峻。作者通过现场调查、数据资料分析、专家咨询和GIS分析等手段,开展了大鹏半岛自然保护区动物廊道构建技术研究。结果显示,大鹏半岛自然保护区野生动物资源较为丰富,有珍稀濒危动物及保护动物61种。结合大鹏半岛自然保护区动物恢复的实际情况,确定了动物廊道恢复的原则,进而确定了两栖类、爬行类和哺乳类动物的恢复对象。结合国际国内廊道恢复构建理论框架,提出了大鹏半岛自然保护区廊道构建的3种类型(景观型、线性型和踏脚石型)、与之相对应的物种及其适宜的生境。就这3种不同类型的廊道进一步提出了恢复构建的原则、技术方法、保护对象的现状分布与潜在分布,并绘制了动物廊道构建示意图。该研究可为城市自然保护区动物廊道恢复提供参考。  相似文献   

2.
南岳珍稀濒危动物的调查研究   总被引:1,自引:0,他引:1  
在南岳野生动物中,珍稀濒危动物共有28种,一级1种,即黄腹角雉TragopanCaboti;二级23种,其中哺乳类5种,鸟类15种,两栖类2种;中国生物多样性保护行动计划优先保护名录二级动物1种;中国优先保护动物中国特有种(A级)4种.本文主要介绍了它们的分类位置、形态特征和在我国的分布,根据南岳现有的资源状况,提出了保护措施与对策.  相似文献   

3.
对宁夏沙坡头自然保护区不同沙化和人工固沙草地地段昆虫和植物群落特征参数、环境因子进行了调查.按不同营养层类群、栖息型类群和重要目分别进行了昆虫多样性变化规律的研究,应用主分量分析法和相关分析法,分析了草原沙化和人工固沙草地生态演替中昆虫不同类群多样性间以及多样性变化与植物、环境因子的关系.结果表明,昆虫多样性随草地沙化的加重而降低,以直翅目、膜翅目和食叶类群的下降率最大;随草地的恢复昆虫多样性趋于增加,以鳞翅目、同翅目、半翅目、脉翅目及捕食类群增长率为大.寄生类群和捕食类群多样性取决于植食类群多样性;杂食类群与地栖性类群成显著性相关.影响昆虫多样性变化的主要环境因子为植物种类、层次结构、盖度和表土层厚度、坚硬度等.  相似文献   

4.
为进一步研究水产养殖动物功能基因的表达调控,采用RT-PCR及RACE法,分离、克隆了近江牡蛎(Crassostrea ariakensis)肝脏β-肌动蛋白基因cDNA全序列. 结果表明,近江牡蛎β-肌动蛋白基因cDNA全长1343bp,其中5′、3′非翻译区(UTR)分别长68bp、144bp,开放阅读框(ORF)为1131bp,编码376个氨基酸. 实验同时成功获得了中华圆田螺(Cipangopaludina cahayensis)、日本沼虾(Macrobrachium nipponensis)、斑鳢(Channa maculata)、胡子鲶(Clarias fuscus)、鳙鱼(Aristichthys nobilis)、鲮鱼(Cirrhinus molitorella)6种重要淡水养殖动物肝脏β-肌动蛋白基因cDNA的核心序列及氨基酸序列. 所获基因与其它动物类群的b-肌动蛋白基因氨基酸同源性高达96%以上,表明软体类、节肢类、鱼类、两栖类、鸟类和哺乳类等不同类群动物b-肌动蛋白基因在生物进化过程中高度保守. 系统发育分析显示软体类、节肢类、鱼类、两栖类、鸟类和哺乳类脊椎动物β-肌动蛋白分类与传统的分类基本一致.  相似文献   

5.
风水林在野生动物多样性保护作用方面的研究还鲜有报道。2010年9月—2011年8月,在中山市选取保存良好的25片风水林,按季节采用样线法对其中的鸟类进行全查。结果表明,(1)所记录到的8 402个体隶属于9目31科88种;其中,林鸟61种,占总物种量的69.32%,个体数达8 265只次,占个体总量的98.37%,且数量排序在前20位的皆为林鸟。(2)物种组成存在季节动态差异,各季节间物种相似性指数较低,在0.53~0.65之间,其中夏季与其他季节间的差异较大;单片风水林物种数较少,在23~43种之间,且每个物种所能占据的风水林数量普遍较少(6.33±7.60),仅有5种鸟类在25片风水林均有分布,且皆为林鸟;(3)鸟类的总物种数以及林鸟物种数与风水林面积之间的关系不符合种-面积关系模型(r=0.109,P=0.604;r=0.250,P=0.229)。风水林对林鸟的保护具有重要作用,且空间格局呈现单片风水林多样性低而整体多样性高的特点,这与各片风水林间树种差异有密切关系。为此,在城市生态环境的改造中,在面积受限的情况下,加强历史性植被的保护和增加不同地域间植被差异性有利于提高当地动物多样性水平。  相似文献   

6.
为进一步研究水产养殖动物功能基因的表达调控,采用RT-PCR及RACE法,分离、克隆了近江牡蛎(Crassostrea ariakensis)肝脏β-肌动蛋白基因cDNA全序列.结果表明,近江牡蛎β-肌动蛋白基因cDNA全长1343bp,其中5′、3′非翻译区(UTR)分别长68bp、144bp,开放阅读框(ORF)为1131bp,编码376个氨基酸.实验同时成功获得了中华圆田螺(Cipangopaludina cahayensis)、日本沼虾(Macrobrachium nipponensis)、斑鳢(Channa maculata)、胡子鲶(Clarias fuscus)、鳙鱼(Aristichthys nobilis)、鲮鱼(Cirrhinus molitorella)6种重要淡水养殖动物肝脏β-肌动蛋白基因cDNA的核心序列及氨基酸序列.所获基因与其它动物类群的β-肌动蛋白基因氨基酸同源性高达96%以上,表明软体类、节肢类、鱼类、两栖类、鸟类和哺乳类等不同类群动物β-肌动蛋白基因在生物进化过程中高度保守.系统发育分析显示软体类、节肢类、鱼类、两栖类、鸟类和哺乳类脊椎动物β-肌动蛋白分类与传统的分类基本一致.  相似文献   

7.
对宁夏沙坡头自然保护区不同沙化和人工固沙草地地段昆虫和植物群落特征参数,环境因子进行了调查,按不同营养层类群,栖息型类群和重要目分别进行了昆虫多样性变化规律的研究,应用主分量分析法和相关分析法,分析了草原沙化和人工固沙草地生态演替中昆虫不同类群多样性间以及多样性变化与植物、环境因子的关系、结果表明,我样性随草地沙化的加重而降低,以直翅目、膜翅目和食叶类群的下降率最大;随草地的恢复昆虫多样性趋于增加  相似文献   

8.
地理因子对物种多样性空间分布格局的影响具有重要意义.文章利用大尺度的物种分布数据以及地理信息,结合GIS和数理统计方法,探讨了中国种子植物物种丰富度的空间分布格局及其与地理因子的关系.结果表明,从南到北,研究区域内物种丰富度总体上呈递减趋势;在经度梯度上,从东到西,物种丰富度呈递增趋势,这可能与其它地理因子的影响有关;在排除其它因子影响的情况下,物种丰富度随着面积的增加,呈递增趋势.但在其它地理因子的综合影响下,面积的影响作用被掩盖或弱化.物种丰富度随着海拔变幅的增加,呈显著递增趋势;物种丰富度与纬度变幅、经度变幅之间不存在显著的(偏)相关性.总体上,纬度、面积和海拔变幅均显著影响物种丰富度的分布格局,但相对而言,面积和纬度起着更为重要的影响.相对海拔变幅而言,海拔变幅与纬度之比值能更好地反映"生境异质性"效应,说明,海拔梯度的"纬度效应"值得关注.  相似文献   

9.
景观格局对植物多样性影响研究进展   总被引:2,自引:0,他引:2  
景观格局对植物多样性有重要影响,植物多样性包括α、β、γ多样性。从景观斑块面积、形状、配置方式、景观类型和尺度效应等方面对植物多样性进行了综述。景观斑块面积能对物种产生质量效应,除部分热带植物外,大部分植物在一定范围内,其物种丰富度与斑块面积呈正相关关系,随着斑块面积的增加,斑块内部种比边缘种数量增加快;但是随着景观破碎化严重,小斑块为物种提供主要栖息地,所以对小斑块的研究和保护具有重要意义。形状复杂的景观斑块能够保持较高的植物多样性,不同植物类群的多样性指数存在差异。景观斑块复杂的边缘,植物物种多样性较高,多为适应性强的边缘种。景观异质性与物种丰富度、β多样性呈显著正相关。景观多样性以及景观斑块之间的连通性与植物多样性呈正相关关系。不同景观类型的合理配置,特别是生态交错区,有利于保持植物多样性。研究发现隔离度对物种丰富度和多样性具有消极影响,主要是由质量效应和邻近效应产生的影响,因为这可以为更多的物种提供更广阔的栖息地,并且有利于种子的传播,从而提高植物的生存率。文章还总结了全球主要的土地利用类型对植物多样性的影响,包括农业用地、草地、森林,多种土地利用类型相结合有助于提高植物多样性,尤其是群落交错区的存在。景观格局与植物多样性的关系存在空间尺度效应,空间尺度效应对植物多样性的研究可以从空间的幅度和粒度中的小尺度、中尺度、大尺度对物种的影响进行研究。景观格局指数高度浓缩了景观格局信息,是反映景观结构和配置等方面特征的简单量化指标,目前应用广泛。未来可从优化景观格局、尺度阈值及影响机制方面做进一步研究。  相似文献   

10.
闫东锋  杨喜田 《生态环境》2010,19(12):2826-2831
研究选取14个分别代表植被群落、地形因子、土壤因子的指标,利用宝天曼自然保护区32块样地资料,研究了物种分布与环境之间关系。采用DCCA法可将该地区木本植物群落划分为3个类型;物种与9个环境因子之间存在显著的相关关系,前4轴可解释物种总变异的94.1%;海拔、坡度、土壤含水量、坡向是影响该地区物种分布的主要因子,其中海拔是指示物种分布变化的最敏感因子。不同指标集团的典型相关分析结果表明:地形与植被因子之间、土壤因子与植被因子之间第1对典范相关系数分别为0.712和0.783,存在着显著的相关关系,影响植被特征的最重要地形因子是海拔和坡度,土壤因子为土壤厚度和土壤含水量,而对地形和土壤反应最敏感的植被指标分别为林分密度和平均树高,群落分布状态是由地形和土壤因子共同作用所控制的。  相似文献   

11.
The invertebrates living on specimens of the brown alga Pelvetia fastigiata, growing in the intertidal zone at La Jolla, California (USA) in November 1975 were enumerated. Within 7 collecting sites, larger plants generally shelter more animal species and individuals than smaller plants. The number of species on a given plant can be described as an equilibrium number; numbers of species and individuals can become similar on defaunated and transplanted algae of comparable sizes placed at the same experimental site. Such equilibria are site-specific because the colonization, immigration and loss rates of animals differ among the sites studied. Relationships between plant size and the number of animal species and individuals on P. fastigiata also differ among the collecting sites. The between-site differences are related to tidal level, to habitat diversity and to habitat patch-size. Small isolated plants without epiphytes shelter few species. The faunas of larger isolated plants at mid-tide levels generally include many thallus-dwelling, tubiculous, vagrant and epiphyte-dwelling species, but few such species commonly inhabit plants within aggregations of P. fastigiata. Within aggregations, the plants host relatively few epiphytes and thus lack habitat diversity, and the net emigration rates of many animals including epiphyte-dwellers are relatively high. Plants within aggregations, however, usually shelter more animal indivuduals than isolated plants. Thus, faunal diversity is reduced, not increased within the largest patches of P. fastigiata.  相似文献   

12.
外来入侵植物紫茎泽兰对昆明地区土壤动物群落的影响   总被引:11,自引:3,他引:11  
2005年雨季前后的6月至9月,共布设144个样方,采样分析了外来入侵植物紫茎泽兰(Eupatorium adeno-phorum)对云南昆明地区针叶林、阔叶林和草地3种主要生态系统类型地表腐叶层土壤动物群落的影响。研究结果表明,紫茎泽兰入侵后土壤动物类群总数显著减少,其中针叶林减少41.3%,阔叶林减少29.0%,草地减少36.7%;土壤动物群落个体总数下降,其中针叶林减少63.5%,阔叶林减少20.4%,草地减少43.2%。紫茎泽兰入侵影响土壤动物群落多样性和均匀度。6月至8月,在没有紫茎泽兰入侵情况下,针叶林和草地生态系统土壤动物群落多样性、均匀度逐步升高;紫茎泽兰入侵后,由于土壤动物类群数量及部分类群个体数量减少,针叶林和草地土壤动物群落多样性、均匀度有所降低。  相似文献   

13.
Abstract:  Species conservation risk assessments require accurate, probabilistic, and biologically meaningful maps of population distribution. In patchy populations, the reasons for discontinuities are not often well understood. We tested a novel approach to habitat modeling in which methods of small area estimation were used within a hierarchical Bayesian framework. Amphibian occurrence was modeled with logistic regression that included third-order drainages as hierarchical effects to account for patchy populations. Models including the random drainage effects adequately represented species occurrences in patchy populations of 4 amphibian species in the Oregon Coast Range (U.S.A.). Amphibian surveys from other locations within the same drainage were used to calibrate local drainage-scale effects. Cross-validation showed that prediction errors for calibrated models were 77% to 86% lower than comparable regionally constructed models, depending on species. When calibration data were unavailable, small area and regional models performed similarly, although poorly. Small area estimation models complement wildlife ecology and habitat studies, and can help managers develop a regional picture of the conservation status for relatively rare species.  相似文献   

14.
张淑花  周利军  张雪萍 《生态环境》2013,(10):1706-1710
土壤动物是土壤污染的敏感指示生物,对土壤环境变化表现出比较灵敏的反映,为了解低质量浓度除草剂对土壤生态系统的影响,进一步推动除草剂使用的安全性评价研究,采用除草剂2,4滴丁酯对土壤动物群落进行室内染毒模拟试验,参照农田施用常规参考质量浓度,设置4个质量浓度梯度和一个不喷施除草剂的对照质量浓度,质量浓度最高限于参考喷施质量浓度的3~4倍,一次染毒后分别于12、24、48和72 h后对土壤动物进行分离并对群落结构特征进行分析。试验共获得土壤动物18655个,隶属于2门,4纲,12目,群落结构分析结果表明低质量浓度2,4滴丁酯导致土壤动物个体数和类群数有所减少,但减少的程度并不大。个体数量变化与质量浓度增高之间呈现较明显负相关(r=-0.856,P〈0.05),种类数变化与质量浓度之间不具有明显的相关性,土壤动物种类数的减少主要取决于稀有类群和极稀有类群,数量的变化则主要是优势类群和常见类群的增减。2,4滴丁酯的施加使得土壤动物群落多样性指数和优势度指数降低,均匀度指数增高。土壤动物个体数量和类群数量变化与染毒后经历的时间之间并未表现出明显的规律性,染毒后不同时间土壤动物优势度指数相差较大,而多样性指数和均匀度指数在不同历时时间段内相差不大。综合各分析结果能够看出,低质量浓度2,4滴丁酯处理会对土壤动物群落造成一定影响,但影响程度并不大。  相似文献   

15.
Abstract:  Most attempts to manage disturbance by visitors to nature reserves concentrate on limiting visitor access in some way, which is often unpopular with both visitors and managers. In a few nature reserves the daily numbers of visitors are limited, an action that need not necessarily reduce the total number of visitors. As a test of the assumptions that underlie this management practice, we examined the relationship between daily visitor numbers and daily failure rates of nests in two species of seabirds. Daily failure rates for Black-legged Kittiwakes ( Rissa tridactyla ) were weakly correlated with daily visitor numbers but indicated that capping daily visitor numbers slightly reduced overall breeding success. This was not the case for Common Murres ( Uria aalge ), where failure rate declined seasonally but was not significantly correlated with visitor numbers. For some species, it appears that capping daily visitor numbers may have small conservation costs.  相似文献   

16.
Urban ecology is emerging as an integrative science that explores the interactions of people and biodiversity in cities. Interdisciplinary research requires the creation of new tools that allow the investigation of relations between people and biodiversity. It has been established that access to green spaces or nature benefits city dwellers, but the role of species diversity in providing psychological benefits remains poorly studied. We developed a user‐friendly 3‐dimensional computer program (Virtual Garden [ www.tinyurl.com/3DVirtualGarden ]) that allows people to design their own public or private green spaces with 95 biotic and abiotic features. Virtual Garden allows researchers to explore what elements of biodiversity people would like to have in their nearby green spaces while accounting for other functions that people value in urban green spaces. In 2011, 732 participants used our Virtual Garden program to design their ideal small public garden. On average gardens contained 5 different animals, 8 flowers, and 5 woody plant species. Although the mathematical distribution of flower and woody plant richness (i.e., number of species per garden) appeared to be similar to what would be expected by random selection of features, 30% of participants did not place any animal species in their gardens. Among those who placed animals in their gardens, 94% selected colorful species (e.g., ladybug [Coccinella septempunctata], Great Tit [Parus major], and goldfish), 53% selected herptiles or large mammals, and 67% selected non‐native species. Older participants with a higher level of education and participants with a greater concern for nature designed gardens with relatively higher species richness and more native species. If cities are to be planned for the mutual benefit of people and biodiversity and to provide people meaningful experiences with urban nature, it is important to investigate people's relations with biodiversity further. Virtual Garden offers a standardized tool with which to explore these relations in different environments, cultures, and countries. It can also be used by stakeholders (e.g., city planners) to consider people's opinions of local design. Programa de Computadora de Jardín Virtual para Uso en la Exploración de los Elementos de Biodiversidad que la Gente Desea en las Ciudades  相似文献   

17.
Species Richness, Endemism, and the Choice of Areas for Conservation   总被引:18,自引:0,他引:18  
Although large reserve networks will be integral components in successful biodiversity conservation, implementation of such systems is hindered by the confusion over the relative importance of endemism and species richness. There is evidence (  Prendergast et al. 1993) that regions with high richness for a taxon tend to be different from those with high endemism. I tested this finding using distribution and richness data for 368 species from Mammalia, Lasioglossum, Plusiinae, and Papilionidae. The study area, subdivided into 336 quadrats, was the continuous area of North America north of Mexico. I also tested the hypothesis that the study taxa exhibit similar diversity patterns in North America. I found that endemism and richness patterns within taxa were generally similar. Therefore, the controversy over the relative importance of endemism and species richness may not be necessary if an individual taxon were the target of conservation efforts. I also found, however, that richness and endemism patterns were not generally similar between taxa. Therefore, centering nature reserves around areas that are important for mammal diversity (the umbrella species concept) may lead to large gaps in the overall protection of biodiversity because the diversity and endemism of other taxa tend to be concentrated elsewhere. I investigated this further by selecting four regions in North America that might form the basis of a hypothetical reserve system for Carnivora. I analyzed the distribution of the invertebrate taxa relative to these regions and found that this preliminary carnivore reserve system did not provide significantly different protection for these invertebrates than randomly selected quadrats. I conclude that the use of Carnivora as an umbrella taxon is an unreliable method for invertebrate conservation.  相似文献   

18.
Animal‐mediated seed dispersal is important for sustaining biological diversity in forest ecosystems, particularly in the tropics. Forest fragmentation, hunting, and selective logging modify forests in myriad ways and their effects on animal‐mediated seed dispersal have been examined in many case studies. However, the overall effects of different types of human disturbance on animal‐mediated seed dispersal are still unknown. We identified 35 articles that provided 83 comparisons of animal‐mediated seed dispersal between disturbed and undisturbed forests; all comparisons except one were conducted in tropical or subtropical ecosystems. We assessed the effects of forest fragmentation, hunting, and selective logging on seed dispersal of fleshy‐fruited tree species. We carried out a meta‐analysis to test whether forest fragmentation, hunting, and selective logging affected 3 components of animal‐mediated seed dispersal: frugivore visitation rate, number of seeds removed, and distance of seed dispersal. Forest fragmentation, hunting, and selective logging did not affect visitation rate and were marginally associated with a reduction in seed‐dispersal distance. Hunting and selective logging, but not fragmentation, were associated with a large reduction in the number of seeds removed. Fewer seeds of large‐seeded than of small‐seeded tree species were removed in hunted or selectively logged forests. A plausible explanation for the consistently negative effects of hunting and selective logging on large‐seeded plant species is that large frugivores, as the predominant seed dispersers for large‐seeded plant species, are the first animals to be extirpated from hunted or logged forests. The reduction in forest area after fragmentation appeared to have weaker effects on frugivore communities and animal‐mediated seed dispersal than hunting and selective logging. The differential effects of hunting and selective logging on large‐ and small‐seeded tree species underpinned case studies that showed disrupted plant‐frugivore interactions could trigger a homogenization of seed traits in tree communities in hunted or logged tropical forests. Meta Análisis de los Efectos de la Perturbación Humana sobre la Dispersión de Semillas por Animales  相似文献   

19.
Abstract:  Human alterations to natural systems have resulted in a loss of biological diversity around the world. Amphibian population losses have been more severe than those of birds and mammals. Amphibian population declines are likely due to many factors including habitat loss, disease, contaminants, introduced species and ultraviolet-B (UVB) radiation. The effect of UVB, however, varies widely among species and can vary within populations of the same species or at different life-history stages. This variation has often led to opposing conclusions about how UVB affects amphibians. We used meta-analysis techniques to explore the overall effects of UVB radiation on survival in amphibians. We also used recently developed factorial meta-analytic techniques to quantify potential interactions between UVB radiation and other stressors on amphibians. Ultraviolet-B radiation reduced survival of amphibians by 1.9-fold compared with shielded controls. Larvae were more susceptible to damage from UVB radiation compared with embryos, and salamanders were more susceptible compared with frogs and toads. Furthermore, UVB radiation interacted synergistically with other environmental stressors and resulted in greater than additive effects on survival when 2 stressors were present. Our results suggest that UVB radiation is an important stressor in amphibians, particularly in light of potential synergisms between UVB and other stressors in amphibian habitats.  相似文献   

20.
Partsch S  Milcu A  Scheu S 《Ecology》2006,87(10):2548-2558
Decomposer invertebrates influence soil structure and nutrient mineralization as well as the activity and composition of the microbial community in soil and therefore likely affect plant performance and plant competition. We established model grassland communities in a greenhouse to study the interrelationship between two different functional groups of decomposer invertebrates, Lumbricidae and Collembola, and their effect on plant performance and plant nitrogen uptake in a plant diversity gradient. Common plant species of Central European Arrhenatherion grasslands were transplanted into microcosms with numbers of plant species varying from one to eight and plant functional groups varying from one to four. Separate and combined treatments with earthworms and collembolans were set up. Microcosms contained 15N labeled litter to track N fluxes into plant shoots. Presence of decomposers strongly increased total plant and plant shoot biomass. Root biomass decreased in the presence of collembolans and even more in the presence of earthworms. However, it increased when both animal groups were present. Also, presence of decomposers increased total N concentration and 15N enrichment of grasses, legumes, and small herbs. Small herbs were at a maximum in the combined treatment with earthworms and collembolans. The impact of earthworms and collembolans on plant performance strongly varied with plant functional group identity and plant species diversity and was modified when both decomposers were present. Both decomposer groups generally increased aboveground plant productivity through effects on litter decomposition and nutrient mineralization leading to an increased plant nutrient acquisition. The non-uniform effects of earthworms and collembolans suggest that functional diversity of soil decomposer animals matters and that the interactions between soil animal functional groups affect the structure of plant communities.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号