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1.
Megaherbivores are known to influence the structure, composition, and diversity of vegetation. In Central Africa, forest elephants act as ecological filters by breaking tree saplings and stripping them of foliage. Much less is known about impacts of megafauna on Southeast Asian rain forests. Here, we ask whether herbivory by Asian megafauna has impacts analogous to those of African forest elephants. To answer this, we studied forest (1) structure, (2) composition, (3) diversity, and (4) tree scars in Belum and Krau, two protected areas of Peninsular Malaysia, and compared the results with those obtained in African forests. Elephants are abundant in Belum but have been absent in Krau since 1993. We found that stem density and diversity, especially of tree saplings, were higher in Krau than in Belum. Palms and other monocots were also more abundant in Krau. In Belum, however, small monocots (<1 m tall) were very abundant but larger ones (>1 m tall) were virtually absent, suggesting size‐selective removal. The frequency of stem‐break scars was equal at Belum and Krau but less than in Central Africa and greater than in the Peruvian Amazon where tapirs are the only megafauna. Pigs and tapirs could also contribute to the high frequency of tree scars recorded in Malaysian forests. Forest‐dwelling elephants in Asia seem to have a reduced impact on tree saplings compared to African forest elephants, but a very strong impact on monocots.  相似文献   

2.
由雪豹(Panthera uncia)捕食散放家畜引起的人兽冲突是目前中国雪豹保护面临的主要挑战之一。四川邛崃山脉地处雪豹分布范围的东南缘, 本研究以邛崃山中部的自然保护区群为研究区, 收集了2014-2018年红外相机调查和动物粪便DNA分析中采集到的雪豹与散放牦牛的分布位点, 使用MaxEnt物种分布模型预测两物种在研究区内的潜在分布范围, 以两物种分布重叠的程度作为评估雪豹捕食家畜潜在风险的指标, 从而识别雪豹-家畜冲突的高危区域。结果表明, 在邛崃山中部的保护区群中, 模型预测的雪豹适宜栖息地面积为871.14 km 2, 牦牛适宜栖息地面积为988.41 km 2, 二者重叠面积达534.47 km 2, 主要分布在研究区西部的高山草甸地区, 占域内雪豹适宜栖息地总面积的61.35%。研究区域内总体上可能存在较高的雪豹-家畜冲突风险。在这些自然保护区以及新建的大熊猫国家公园的管理规划中, 应把高山放牧作为对区内野生雪豹种群的关键威胁之一, 重点关注模型预测的人兽冲突高危区域, 通过改变社区牧业管理方式、发展社区替代生计等方式, 降低潜在冲突的风险。  相似文献   

3.
物种的分布变化是衡量生物多样性变化的一个重要层面,也是生物多样性变化研究领域备受关注的热点。根据对四川省东南地区6县14个乡镇的访问调查,分析了四川省东南部云豹(Neofelis nebulosa)分布区的变化趋势,并对近10年潜在有无云豹分布的区域在1988年和2017年的景观格局进行对比分析,探讨了四川东南地区云豹分布区变化的原因。结果显示:(1)40年前云豹曾在调查区域广泛分布,近40年来云豹分布范围呈现逐渐缩减的趋势,到近10年潜在有云豹分布的仅3个县3个乡镇;(2)天然阔叶林是云豹适宜的生境,潜在有云豹分布地区阔叶林在近30年里均是面积最大的景观类型,30年间增加了18.13%。潜在无云豹分布地区阔叶林在30年前占比为13.67%,30年间减少了39.29%,其主要景观类型在30年间由农业用地转换为竹林类型;(3)30年间,潜在有无云豹分布地区阔叶林破碎化程度均加剧,而潜在无云豹分布地区的破碎化程度较潜在有云豹分布地区严重;(4)潜在有无云豹分布区域居民野生动物保护意识均不强烈,在潜在无云豹分布区域的保护意识和意愿稍高;(5)本研究认为,早在40年前由于人为捕杀和土地开垦,就导致云豹种群在研究区域内衰退,近30年虽然农业用地大幅转换为竹林使森林总面积增加,但并未对云豹的保护起到积极作用,阔叶林的生境退变则使前期已经衰退的云豹种群分布区持续缩减,以致难觅踪迹。  相似文献   

4.
于1997年10月到1999年10月在泰国KhaoYai国家公园对两种同域分布的物种(即豹猫和云豹)进行了研究。使用带诱饵的陷阱捕捉了这些动物,进行麻醉,确定了性别、年龄,并戴上了无线电项圈,对6只雌性豹猫和4只雄性豹猫进行了1—18个月的无线电追踪。豹猫在干旱季节的利用区域大于雨季,雄性利用的区域大于雌性。在夜间和晨昏时节,豹猫活动增加,但是并没有节律性活动。所有豹猫个体在旱季和雨季的活动都相似,但雄性个体的白天活动多于雌性。豹猫的行走距离有性别差异但是没有季节差异;其食物以鼠类为主。分别对1只雌性云豹和1只雄性云豹进行了17个月和7个月的无线电追踪,雌性个体的活动面积为39.4km^2,而雄性个体活动面积为42.2km^2,核心区都是2.9km2。云豹对半绿林的使用大于其它类型的植被,在晨昏和夜间的活动增加,其活动无节律。  相似文献   

5.
The Malay civet (Viverra tangalunga) is found throughout Southeast Asia, but there have been very few studies on its natural history and ecology. We present here the results from the first radio telemetry study of this species on Peninsular Malaysia and compared our findings to similar studies on Borneo and Sulawesi. From August 2004 to August 2006, we captured 11 Malay civets in Krau Wildlife Reserve and radio-tracked seven adults (four males and three females). The mean weight of males (6.6 kg) was significantly higher than females (5.8 kg). Both sexes on Peninsular Malaysia were larger than their counterparts on Borneo and Sulawesi. There was no significant difference between the mean sizes of male and female home ranges on Peninsular Malaysia; the mean home range size for both sexes was 143 ha (95% MCP), which was larger than the mean range size recorded on Borneo and Sulawesi. We found that the Malay civet is a solitary, territorial species on Peninsular Malaysia: mean range overlap was 15% for males and 0% for females, and the home range of each male overlapped one or two females. Malay civets were mainly nocturnal, with some periods of rest during the night; daytime rest sites were within dense ground cover. Lowland forest is an essential habitat for this species; although Malay civets were sometimes found in plantations, they did not venture far from forested habitat.  相似文献   

6.
Identifying the primary causes affecting population densities and distribution of flagship species are necessary in developing sustainable management strategies for large carnivore conservation. We modeled drivers of spatial density of the common leopard (Panthera pardus) using a spatially explicit capture–recapture—Bayesian approach to understand their population dynamics in the Maputaland Conservation Unit, South Africa. We camera‐trapped leopards in four protected areas (PAs) of varying sizes and disturbance levels covering 198 camera stations. Ours is the first study to explore the effects of poaching level, abundance of prey species (small, medium, and large), competitors (lion Panthera leo and spotted hyenas Crocuta crocuta), and habitat on the spatial distribution of common leopard density. Twenty‐six male and 41 female leopards were individually identified and estimated leopard density ranged from 1.6 ± 0.62/100 km2 (smallest PA—Ndumo) to 8.4 ± 1.03/100 km2 (largest PA—western shores). Although dry forest thickets and plantation habitats largely represented the western shores, the plantation areas had extremely low leopard density compared to native forest. We found that leopard density increased in areas when low poaching levels/no poaching was recorded in dry forest thickets and with high abundance of medium‐sized prey, but decreased with increasing abundance of lion. Because local leopard populations are vulnerable to extinction, particularly in smaller PAs, the long‐term sustainability of leopard populations depend on developing appropriate management strategies that consider a combination of multiple factors to maintain their optimal habitats.  相似文献   

7.
One of the most extreme freshwater habitats in Peninsular Malaysia is the peat swamp forest, with dark-coloured and highly acidic waters. Surprisingly, little is known about blackwater fishes in Peninsular Malaysia. Until 1968, only 26 fish species were known from blackwaters throughout Peninsular Malaysia, of which only one can be regarded as stenotopic. A recent intensive survey of part of the North Selangor peat swamp forest yielded 47 species, of which 14 are probably stenotopic taxa. These include four undescribed species and several new records for western Peninsular Malaysia. These discoveries are significant in that they include the family Chaudhuriidae which until 1985, was not reported from Sundaic Southeast Asia, and the rare genus Encheloclarias which had not been encountered for over 50 years. The rapid rate of destruction of the peat swamp forest owing to development, forestry and agricultural activities must be halted or slowed significantly to enable the proper zoological surveys and studies to be conducted. Conservation plans and environmental impact assessments based on inadequate sampling and knowledge of species present is acutely dangerous. There are no longer substantial undisturbed blackwater peat swamp forests left in most of Peninsular Malaysia. Conservation of the remaining blackwater biotopes is critically important if extinction of many species, here regarded as economically valuable renewable resources, is to be prevented.  相似文献   

8.
In a recent article in this journal Zhang and colleagues investigated the factors affecting the distribution of a species of epiphytic fern Asplenium nidus L. in rain forest in Peninsular Malaysia. Here we suggest that their findings may be interpreted in the light of there being two cryptic species present, each with different ecologies, as is the case in Malaysian Borneo. We also discuss the implications of the existence of cryptic species when attempting to conserve forest diversity in the face of climate change and habitat conversion. Abstract in Malay is available at http://www.blackwell‐synergy.com/loi/btp .  相似文献   

9.
Three of Malaysia’s endangered large mammal species are experiencing contrasting futures. Populations of the Sumatran rhino (Dicerorhinus sumatrensis) have dwindled to critically low numbers in Peninsular Malaysia (current estimates need to be revised) and the state of Sabah (less than 40 individuals estimated). In the latter region, a bold intervention involving the translocation of isolated rhinos is being developed to concentrate them into a protected area to improve reproduction success rates. For the Asian elephant (Elephas maximus), recently established baselines for Peninsular Malaysia (0.09 elephants/km2 estimated from one site) and Sabah (between 0.56 and 2.15 elephants/km2 estimated from four sites) seem to indicate globally significant populations based on dung count surveys. Similar surveys are required to monitor elephant population trends at these sites and to determine baselines elsewhere. The population status of the Malayan tiger (Panthera tigris jacksoni) in Peninsular Malaysia, however, remains uncertain as only a couple of scientifically defensible camera-trapping surveys (1.66 and 2.59 tigers/100 km2 estimated from two sites) have been conducted to date. As conservation resources are limited, it may be prudent to focus tiger monitoring and protection efforts in priority areas identified by the National Tiger Action Plan for Malaysia. Apart from reviewing the conservation status of rhinos, elephants and tigers and threats facing them, we highlight existing and novel conservation initiatives, policies and frameworks that can help secure the long-term future of these iconic species in Malaysia.  相似文献   

10.
In this study, we have reported two direct observations of individuals from a one-male group of proboscis monkeys (Nasalis larvatus) being killed by clouded leopards (Neofelis diardi) in the riverine forest along the Menanggul river, a tributary of the Kinabatangan river in Sabah, Malaysia. One of the two individuals was an infant female and the other was a juvenile female. Based on literature reviews and the observations reported here, we suggest that clouded leopard and crocodile might be significant potential predators of proboscis monkeys of any age or sex and that predation threats elicit the monkeys' anti-predator strategies. Moreover, the observations of the monkeys' behaviour when the group is attacked by a predator suggest that the adult males in one-male groups play an important role as protectors.  相似文献   

11.
报道了在海南热带雨林国家公园内发现的兰科牛齿兰属中国一新记录种:广椭牛齿兰[Appendicula ovalis(Schltr.) J.J.Sm. ex Mansf.]。该种原分布于马来半岛、苏门答腊岛、爪哇岛、婆罗洲、苏拉威西岛,在形态上与国内记录的4种牛齿兰属植物均有较大差别,如茎中部具分枝、叶广椭圆形、单个花序仅着生1朵花、且唇瓣扭转具粉紫色斑块等特征。对产自海南的该种形态和生境进行了详细描述,并提供高清解剖照片。凭证标本保存于海南大学林学院教学标本馆(HUFB)。  相似文献   

12.
可靠的种群密度数据对野生动物的保护和管理十分重要。豹猫(Prionailurus bengalensis)是中国分布最广且常见的猫科动物, 但野生种群密度估算的研究并不多。本研究于2020年6月至2021年5月在香港新界嘉道理农场暨植物园开展红外相机调查, 利用空间标记-重捕法估算当地豹猫的种群密度并用核密度估计方法分析其活动节律。本次调查以网格方式布置红外相机, 在约1.5 km2的研究范围之内设置了19个相机位点, 每个位点安装2台相机以获取豹猫身体两侧花纹来进行个体识别。连续12个月调查共捕获113次有效的豹猫拍摄事件, 当中仅61次事件的照片足够清晰以进行个体识别。基于种群封闭的要求, 我们以2个月为单位将12个月的数据分为6个采样期去分析豹猫种群密度, 结果显示仅两个采样期的估算值最为准确, 分别为0.64 ± 0.31 (0.26-1.55)只/km2和0.87 ± 0.48 (0.31-2.40)只/km2, 是已知全球豹猫密度最高的地点之一。结果还发现, 雨季研究地点的豹猫并无明显的日活动节律, 在旱季则偏夜行-晨昏行性多一些, 但也有一定的日间活动; 雨季和旱季的日活动节律无显著差异。本研究是首次以个体识别配以空间标记-重捕模型对中国大陆地区豹猫种群密度调查的研究; 我们也提出一些关于红外相机架设方法的建议, 以提高照片个体识别的准确度并增加重捕次数, 最后提高密度估算的准确度。本研究也进一步证明豹猫适应性极强, 在活动节律上表现出极高的可塑性, 在严格保护下可以恢复健康的种群。  相似文献   

13.
The Muñoa’s Pampas cat (Leopardus munoai) is a relatively understudied species restricted to open savannas and grasslands of Southern Brazil, Uruguay and NE Argentina, that has been recently split from the broader “Pampas cat” species complex. Only three documented records of the species have been published since the year 2000 for the Argentine portion of its distribution, a situation that led to speculations regarding its conservation status in Argentina. We conducted an intensive camera-trap survey (2,067 camera-trapping stations and 15,560 camera-trapping days) to assess the presence of the Muñoa’s Pampas cat in an area of 275.3 km2 within the Iberá National Park and the adjacent Iberá National Reserve, Corrientes province, Argentina. Four records of Muñoa’s Pampas cat were obtained, representing at least two adults and one young individual. Only one camera-trapping record of this species had been previously obtained in Argentina, during a survey carried out in 2009 in the same study area, despite an important camera-trapping effort in the Corrientes province. All camera-trap records of Muñoa’s Pampas cat in Argentina are concentrated in areas of temporally flooded grasslands locally known as “Malezales”, suggesting that this habitat type is critically important for the conservation of this rare felid. The Iberá National Park and the adjacent Iberá National Reserve provide the adequate framework for the conservation of an important piece of habitat for Muñoa’s Pampas cat and constitute a stronghold for the species in Argentina.  相似文献   

14.
Many habitat patches in tropical landscapes have become less suitable for wildlife due to an increase in anthropogenic disturbances. An index of habitat suitability based on the ecological factors that collectively determine the suitability of an organism's habitat is important for conservation planning. However, a widely accepted and comprehensive multi-criteria habitat suitability index for umbrella species is still lacking, particularly in areas where information related to the biology and ecology of the species of interest is not available. Therefore we develop preliminary habitat maps and measure the degree of habitat suitability for large mammals, focusing on four umbrella species in the State of Selangor, Peninsular Malaysia: Panthera tigris jacksoni (Malayan tiger), Tapirus indicus (Malayan tapir), Helarctos malayanus malayanus (Malayan sun bear), and Rusa unicolor cambojensis (sambar deer). The former two are endangered and the latter two are vulnerable according to the IUCN Red List. The suitability of habitat patches for each species was measured across the entire study area as well as in nine wildlife protected areas by integrating GIS data and expert opinion. Expert opinions were used as the source of information regarding the stresses faced by the species because there was insufficient information available from ground surveys.We developed an index and maps of habitat suitability for each species, which were then integrated to represent a combined index (ranging from 0 to 27) and spatially explicit maps of the area's habitat suitability for large mammals. The average large mammal habitat suitability index value of the State of Selangor (9) indicates that many habitat patches have become unsuitable for such species. Of the nine wildlife protected areas, Fraser's Hill (22), Sungai Dusun (22), and Bukit Kutu (21) are very suitable; Klang Gate (20) and Templers Park (17) are suitable; and the remaining four are unsuitable for large mammals. We assume that this preliminary habitat suitability index and mapping are useful for conservation planning of wildlife habitats at both landscape and regional scales, as well as providing an initial foundation for revision by future research with significant new information.  相似文献   

15.
雪豹是全球生物多样性保护的旗舰物种,精准评估雪豹栖息地质量可为其种群保护提供科学参考。本文选取地形、气候、植被类型和人为干扰等环境因子,采用景观连接度和MaxEnt模型两种方法,对祁连山国家公园青海片区雪豹栖息地质量进行评价。结果表明:高适宜栖息地主要分布在研究区的西部和中部,适宜面积占青海片区总面积的71.8%~77.5%,两种方法预测的适宜栖息地重叠区为8 979.1 km2,占青海片区总面积的56.7%;39.8%~43.3%的适宜栖息地分布在一般控制区,56.7%~60.2%的适宜栖息地分布在核心保护区;疏勒河源区适宜栖息地面积最多,石羊河源区适宜栖息地面积最少,黑河源区适宜栖息地面积占比最高,约为77.1%~91.8%。适宜栖息地面积整体呈现自东向西递增的趋势。一般控制区分布有较大面积的雪豹栖息地,人类活动将是一般控制区雪豹栖息地的潜在威胁。本研究对优化雪豹就地保护措施提供科学借鉴与参考。  相似文献   

16.
Reservation of forest in riparian buffers is common practice in commercial forestry areas worldwide, potentially providing valuable habitat for biodiversity dependent on mature forest. However, the habitat value of narrow reserve corridors can be compromised by edge effects. We investigated the habitat value of streamside buffers in wet eucalypt forest for ground-dwelling beetles in Tasmania, Australia. Beetles were collected with pitfall traps in five replicates of four habitats: unlogged corridors of mature forest in streamside reserves (buffers) with clearfelling-derived logging regeneration either side; continuous mature upslope forest; continuous mature riparian forest; and <20-year-old upslope clearfelling-derived logging regeneration. Streamside reserve widths on each side of the stream were on average 40 ± 6 m (±95% CI) from reserve edge to stream. Beetle assemblages in logging regeneration differed substantially from those in the unlogged habitats, including the streamside reserves. Streamside reserve assemblages nevertheless differed from those of the continuous unlogged areas. Assemblage composition in streamside reserves was most similar to that in continuous mature riparian forest, although beetle diversity was higher in the reserves. Our results suggest that although streamside reserves provide habitat for the majority of commonly collected beetle species occurring in continuous mature forest, wider reserve corridors in the wet eucalypt forests of Tasmania may be required to provide habitat that is not edge-affected.  相似文献   

17.
功能分区是统一协调国家公园不同保护管理目标的主要措施, 对于国家公园的有效管理有重要意义。钱江源国家公园是我国首批国家公园体制试点区之一, 被分为核心保护区、生态保育区、游憩展示区和传统利用区4个部分, 对应不同的保护管理措施。本研究分析了钱江源国家公园体制试点区现有功能分区与其首要保护对象黑麂(Muntiacus crinifrons)的适宜栖息地之间的空间关系。在红外相机调查获取的94个黑麂分布点的基础上, 结合海拔、地形、植被特征、人为活动干扰等15个环境特征变量, 采用MaxEnt模型预测国家公园内黑麂适宜栖息地的空间分布。结果表明, 黑麂倾向于出现在森林较为原始和道路密度较低的区域, 其适宜栖息地面积42.5 km 2, 占国家公园总面积的16.9%。其中, 69.3%的黑麂适宜栖息地位于核心保护区, 30.4%位于生态保育区, 表明国家公园现有功能分区能很好地满足黑麂栖息地保护的需求。此结果也证明黑麂可以作为其分布范围内保存较好的亚热带森林生态系统的指示性物种。通过生境恢复、廊道建设和跨省共建促进黑麂栖息地的完整性保护, 是加强该区域黑麂栖息地保护的关键措施。  相似文献   

18.
One of the available tools for mapping the geographical distribution and potential suitable habitats is species distribution models. These techniques are very helpful for finding poorly known distributions of species in poorly sampled areas, such as the tropics. Maximum Entropy (MaxEnt) is a recently developed modeling method that can be successfully calibrated using a relatively small number of records. In this research, the MaxEnt model was applied to describe the distribution and identify the key factors shaping the potential distribution of the vulnerable Malayan Sun Bear (Helarctos malayanus) in one of the main remaining habitats in Peninsular Malaysia. MaxEnt results showed that even though Malaysian sun bear habitat is tied with tropical evergreen forests, it lives in a marginal threshold of bio-climatic variables. On the other hand, current protected area networks within Peninsular Malaysia do not cover most of the sun bears potential suitable habitats. Assuming that the predicted suitability map covers sun bears actual distribution, future climate change, forest degradation and illegal hunting could potentially severely affect the sun bear’s population.  相似文献   

19.
Scott L. Collins 《Oecologia》1983,59(2-3):246-252
The habitats occupied by species of wood warblers (Emberizidae) were compared at two study areas, Itasca State Park, Minnesota and Mount Blue State Park, Maine. Univariate comparisons of each variable of habitat structure show geographic differences for each species of warbler. Habitats available were also different because small trees were always more dense in Maine than in Minnesota. The Black-throated Green Warbler had the most dissimilar habitat with 9 of 11 variables different at the two sites.Cluster analysis identified four generalized habitat groups containing (1) species occupying territories with high percent shrub cover, (2) forest species from Maine, (3) forest species from Minnesota and (4) open country species. Reciprocal averaging ordination was used to identify habitat gradients at each site. The first axis of the Maine and Minnesota ordinations was a gradient from open country with dense ground cover to forest vegetation. The second axes differed, however. In Minnesota, the gradient separated medium deciduous trees from large conifers, whereas in Maine, vegetation graded from medium and large deciduous trees to coniferous habitats. Spearman rank correlation indicated that the warblers were similarly arranged along both habitat axes at each site despite differences in axis loadings of habitat variables.A combined reciprocal averaging ordination separated forest and shrub-forest edge species in Maine from the same two species groups in Minnesota along a smaller to larger tree axis. The results clearly demonstrate that habitat structure is not consistent throughout the range of many widely distributed species. It is suggested that the similar arrangement of species along the habitat axes probably results from an individualistic distribution of opportunistic bird species. Variation is probably induced at a site level by intraspecific competition for territories, small-scale vegetation dynamics, and resource fluctuation that occurs both within and between seasons.  相似文献   

20.
Canine morphology is analysed at seven intervals along the crown in both anteroposterior and lateromedial perspective in seven species of large felids. The puma and the snow leopard have stout, rather conical canines, whereas those of lions, jaguars, and tigers bear substantial resemblance to each other, reflecting their phylogenetic relationships, and are less conical and large. The canines of the leopard are intermediate in morphology between those of the other species, probably reflecting its more generalized diet. The clouded leopard has very large and blade-like canines, which are different from the other analysed species. Canine bending strengths to estimated bite forces appear to differs less among the species than morphology, indicating that the evolution of canines has been constricted with respect to their strength in failure, probably owing to their being equally important for species fitness. However, the clouded leopard again stands out, having a high estimated bite force and rather weak canines in bending about the anteroposterior as well as lateromedial planes compared to the other species. Canine morphology to some extent reflects differences in killing mode, but also appears to be related to the phylogeny. The marked divergence of the clouded leopard is presently not understood.  © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 91 , 573–592.  相似文献   

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