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随着录音设备性能的提高和硬件价格的降低,基于录音评估声景来反映生境特征和生物多样性的方法得到快速发展。声学指数是对声音整体特征的量化,受到录音生境和生物组成的共同影响,因此可构建声学指数与生境特征和生物组成的关联。按照作用的尺度,声学指数可分为两类:反映录音内信息的alpha声学指数和比较不同录音之间差异的beta声学指数。随着录音设备的普及,以及在大尺度上进行生物监测工作的增加,对不同时间、不同地点的录音进行比较的需求日益迫切。因此,beta声学指数的开发和应用是声学指数研究的重要方向。本文介绍了11个常用的beta声学指数,并探讨了这些指数的数学特征(非负性、同一性、对称性、直递性、有限性)。本文还通过文献检索获取了beta声学指数在实证中的应用情况,发现研究中常使用beta声学指数反映时间节律、生境特征的差异或生物组成的改变。最后,本文指出了beta声学指数研究/应用中迫切需要发展的3个方向:开发新的指数、优化已有指数的计算方式、增加实证研究。 相似文献
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2008年7月至2011年11月间先后4次调查了江西婺源森林鸟类自然保护区陆生贝类资源,共采得陆生贝类57种(亚种)(含3个未定种),隶属16科28属,其中1种为江西省新纪录种,优势种为长柱倍唇螺Diplommatina paxillus longipalatalis和细纹灰尖巴蜗牛Bradybaena ravida redfieldi。区系组成以东洋界成分为主,占种类总数的64.9%。分析11个采集点生物多样性指数结果表明,Margalef丰富度指数(dMA)范围为0.423~5.501;Shannon-Wiener多样性指数(H')范围为0.047~2.333;Pielou均匀度指数(Jsw)范围为0.030~0.438。与其他自然保护区相比较,婺源森林鸟类自然保护区陆生贝类物种较丰富,与阳际峰国家级自然保护区物种相似系数较高,与甘肃白水江国家级自然保护区物种相似系数较低,陆生贝类物种多样性有明显区域性特征。 相似文献
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雾网应用于森林鸟类群落生态学研究已有20多年的历史,用雾网研究森林中行动隐蔽、少鸣唱、没有领域的鸟类,特别是森林林下鸟类十分有效.该方法不受研究者经验的影响,可以对不同地区、不同群落进行比较研究.国外学者认为雾网是研究森林鸟类群落必不可少的研究工具.文中着重介绍了雾网的优缺点及其在森林鸟类群落研究中的应用,以期推动我国相关学科的研究. 相似文献
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北京紫竹院公园鸟类群落多样性分析 总被引:3,自引:0,他引:3
2004年9月~2005年6月在北京紫竹院公园进行鸟类群落调查.共记录到鸟类52种,隶属于11目26科.其中夏候鸟17种,冬候鸟4种,旅鸟28种,留鸟13种.鸟类的种类和数量随季节变化有明显差异.春、秋季鸟类种类丰富,秋季达到最高;冬季鸟类数量达到最高.优势种有灰椋鸟Sturnus cineraceus、麻雀Passer montanus、喜鹊Pica pica、厌喜鹊Cyanopica cyana、绿头鸭Anas platyrhynchos、鸳鸯Aix galericulata等.鸟类群落多样性指数和均匀度指数变化趋势类似,春、秋季高,冬季低,而优势度指数的变化是冬季最高,春、秋季低.鸟类多样性增加主要是由于春、秋季的候鸟迁徙.保证一定的公园面积、增加空间异质性、合理配置资源,有利于保护鸟类的多样性. 相似文献
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样点法在森林鸟类调查中的运用 总被引:2,自引:1,他引:2
样点法由于具有易于实施、更易做到随机化或系统化以及适合于复杂及斑块化生境等优点,已成为目前使用最为广泛的森林鸟类调查方法。本文在介绍样点法的假设条件、类型和影响鸟类调查准确性因素的基础上,重点介绍了样点法在调查森林鸟类需要考虑的样本大小、样点布设、调查时间、每点的停留时间和调查周期等。同时也分析了样点法的不足,并提出样点法与网捕法结合是提高调查结果准确性的有效途径。 相似文献
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广东车八岭自然保护区鸟类多样性分析 总被引:6,自引:4,他引:6
于1998年1月-2000年12月对广东车八岭保护区鸟类进行了调查,加上文献记载,共计有223种鸟,隶属于42科、16目。其中东洋种占61.9%、古北种占27.3%、广布种占10.8%。对该区鸟类以G-F指数进行多样性统计,得F指数为27.85,G指数为4.692,G-F指数为0.832。在该区鸟类名录中,单种科13科,占总科数的31.0%;非单种科29科,占总科数的69.0%,所以G-F指数比较高。在本区鸟类各科中,鹅科、鹰科、雉科的多样性最高,GFk指数分别为3.106、2.409、2.08,占本区F指数的27.3%。与处于不同纬度地区的鸟类多样性相比,车八岭保护区的鸟类丰富程度与热带的尖峰岭地区及纬度更高的的江西武夷山地区的鸟类丰富度相当。 相似文献
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中重度火干扰通常会显著改变森林结构与功能,甚至引发森林演替,严重影响鸟类群落组成与多样性。大兴安岭是我国林火高发热点地区之一,但林火对鸟类多样性影响的研究较少,特别是对功能多样性的影响尚不清楚。本研究于2021年7–8月在大兴安岭地区的黑龙江南瓮河国家级自然保护区,采用样点法对森林鸟类展开调查,量化不同林火干扰时间下森林内部和边缘鸟类功能多样性的差异。同时,通过系统性文献检索,进一步比较了大兴安岭地区不同林分组成与鸟类功能多样性的关系。结果发现:(1)不同林火事件后,森林内部鸟类群落的组成差异较小,但边缘鸟类组成差异较大;(2)森林内部的鸟类功能丰富度和均匀度随火后恢复时间增加逐渐升高,并且在火后早期阶段森林边缘的功能丰富度更高;(3)随着火后恢复时间的增加,森林边缘的留鸟比例增加,夏候鸟比例减少;(4)在大兴安岭地区,针阔混交林中的鸟类功能丰富度显著高于兴安落叶松(Larix gmelinii)林。本研究建议在大兴安岭寒温带森林中,保持森林内部结构稳定性,同时提升火后早期阶段森林边缘的植被多样性,这有利于维持鸟类较高的功能丰富度和功能均匀度。 相似文献
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Anthropogenic noise reduces bird species richness and diversity in urban parks 总被引:1,自引:0,他引:1 下载免费PDF全文
Alyne Perillo Luiz G. Mazzoni Luiza F. Passos Vinicius D. L. R. Goulart Charles Duca Robert J. Young 《Ibis》2017,159(3):638-646
Anthropogenic noise is becoming more prevalent in the world and has been shown to affect many animal species, including birds. The impact of such noise was measured in Neotropical urban parks to assess how the noise affects avifauna diversity and species richness. We sampled bird species, and concurrently measured sound pressure (noise) levels (Leq, equivalent noise levels) in eight urban green areas or parks located in a large city (Belo Horizonte) in south‐eastern Brazil over a 1‐year period. The diversity of sampled points was measured by means of total species richness, Fisher's alpha and Shannon–Wiener diversity indices. Noise levels within all parks were greater than those in natural areas. We found that an increase in noise levels and the area of open habitats surrounding sampling points were negatively related to species richness. Social factors reflecting increased urbanization, such as higher incomes, were also negatively correlated with bird species richness. However, noise was the factor that explained most of the variance. These results suggest that anthropogenic noise can have a significant negative impact on the conservation value of urban parks for bird species. 相似文献
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Tshering Dema Michael Towsey Sherub Sherub Jigme Sonam Kinley Kinley Anthony Truskinger Margot Brereton Paul Roe 《Freshwater Biology》2020,65(1):153-164
- Growing developmental activities, such as hydropower construction, farm roads, and other human activities, are affecting the critically endangered white-bellied heron (WBH). Out of a known global population of 60, 28 individuals inhabit the river basin area and freshwater lakes and ponds of Bhutan. Several constraints impede continuous monitoring of endangered species, such as the isolated and cryptic nature of the species and the remoteness of its habitat; to date, there are no long-term reference data or techniques implemented for continuous monitoring of this species.
- In this study, we designed acoustic detection and habitat characterisation methods using long-duration recordings from three habitat areas in Bhutan. Acoustic indices were extracted and used to implement a species-specific call detector and to generate habitat soundscape representations. Using WBH calls annotated in month-long recordings from a known site, a novel indices-based detector was implemented and tested. A total of 960 hr of continuous audio recordings from three habitats in Bhutan were analysed.
- We found that a species call detector implemented using a combination of acoustic indices (that includes measures of spectral and temporal entropy and different angles of spectral ridges) has a correct detection rate of 81%. Additionally, visual inspection of the species’ acoustic habitat using long-duration false-colour spectrograms enabled qualitative assessment of acoustic habitat structure and other dominant acoustic events.
- This study proposes a combined approach of species acoustic detection and habitat soundscape analysis for holistic acoustic monitoring of endangered species. As a direct outcome of this work, we documented acoustic reference data on the critically endangered WBH from multiple habitat areas and have analysed its temporal vocalisation patterns across sites.
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林下草本植物是城市森林生物多样性重要的保育层,敏感度高,可塑性强,能有效反映城市植被对城市化的响应策略。本研究在上海市范围内沿中心城区—近郊—远郊的城乡梯度,共选取16块林地共398个样方,分析了上海市森林草本群落区系特征和多样性格局沿城乡梯度的变化规律。结果表明:上海城市森林生态系统中共有草本植物144种,隶属47科118属;多年生草本74种,占半数以上(51.39%);属和种分别涵盖18和12个分布区类型和亚型,以热带和温带成分为主;外来植物28种,占比接近20%;物种丰富度和群落多样性指数均沿中心城区—近郊—远郊梯度先下降后上升,近郊最低,远郊最高;中心城区物种构成与远郊相似,与近郊差异最大。本研究揭示了城市森林生态系统中草本植物的分布格局以及多样性沿城乡梯度的变化规律,为深入开展城市化与城市植被的互作研究提供了理论支撑,为管理部门制定相关政策提供了科学依据。 相似文献
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JEAN-MARC THIOLLAY 《Biodiversity and Conservation》1997,6(8):1155-1173
The composition and structure of bird communities, and the damage to forest structure were surveyed in northern French Guiana (northeastern Amazonia) one year and ten years after selective logging and compared with the situation in a similar undisturbed primary forest. A point-count method was used in which 937 0.25ha sample plots were censused for 20 minutes each, and their vegetation structure was measured. On average, 38% of the forest undergrowth was destroyed, then invaded by dense regrowth, and up to 63% of the canopy was substantially opened as a result of selective logging. Hunting pressure also increased due to access roads opened for logging. Among the 256 species recorded, overall bird species richness and abundance were depressed by 27–34% in the logged areas compared to primary forest. The most vulnerable guilds, which decreased by 37–98% in abundance, were mature forest understorey species, especially terrestrial ones and mixed flocks of insectivores. Hummingbirds, small gaps, vine tangles and canopy species did not decrease, nor increase significantly after logging. Only species naturally associated with dense second growth, forest edges and large gaps actually increased. Habitat specialization was the major determinant of vulnerability to logging, and, to a lesser degree, size (large) and diet (insectivorous), but foraging behaviour and rarity had little effect. Bird sensitivity to changes in logged forest structure may involve physiological intolerance, reduced food categories, increased exposure to predators, too dense understorey for their specific foraging behaviour and/or avoidance of gaps. Suggested improvements of current forest management and logging techniques for the maintenance of a higher proportion of the original biodiversity include minimizing logging damages, long rotations (>50 years) between cuts, and keeping unlogged forest patches within logging concessions. 相似文献
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Wei Liu Dandan Yu Sijia Yuan Jianfeng Yi Yun Cao Xiufen Li Haigen Xu 《Ecology and evolution》2022,12(7)
The biodiversity in mountainous ecosystems is high but is threatened by rapid environmental change. Urbanization and other anthropogenic factors in the mountains can affect land use and spatial fragmentation. Moreover, patterns of habitat are closely related to elevation and have a major effect on montane biodiversity. The aim of this study was to analyze the effects of spatial fragmentation on the vertical distribution pattern of bird diversity by characterizing the structure of the bird community, species diversity, and landscape factors at different altitudes. From 2016 to 2019, this study made a four years of continuous monitoring of the breeding birds. The result indicated that Mount Tai harbored a high bird diversity. Bird richness, abundance, and Shannon‐Wiener index decreased with latitude in Mount Tai monotonically. Moreover, the structure of bird communities varied along altitudinal gradients, and some special species were supported in different elevational bands due to the environmental filtering. Road density, number of habitat patches, patch density, and the percentage of forest were significantly related to bird diversity. Sufficient habitat and more patches in the low‐mountain belt supported higher bird diversity. The middle‐mountain belt and high‐mountain belt showed contrasting patterns. Our results highlight the effects of on‐going urbanization and human activities on montane biodiversity and emphasize the need for artificial habitats in the mountains to be managed. 相似文献
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Darren S. Proppe Christopher B. Sturdy Colleen Cassady St. Clair 《Global Change Biology》2013,19(4):1075-1084
More humans reside in urban areas than at any other time in history. Protected urban green spaces and transportation greenbelts support many species, but diversity in these areas is generally lower than in undeveloped landscapes. Habitat degradation and fragmentation contribute to lowered diversity and urban homogenization, but less is known about the role of anthropogenic noise. Songbirds are especially vulnerable to anthropogenic noise because they rely on acoustic signals for communication. Recent studies suggest that anthropogenic noise reduces the density and reproductive success of some bird species, but that species which vocalize at frequencies above those of anthropogenic noise are more likely to inhabit noisy areas. We hypothesize that anthropogenic noise is contributing to declines in urban diversity by reducing the abundance of select species in noisy areas, and that species with low‐frequency songs are those most likely to be affected. To examine this relationship, we calculated the noise‐associated change in overall species richness and in abundance for seven common songbird species. After accounting for variance due to vegetative differences, species richness and the abundance of three of seven species were reduced in noisier locations. Acoustic analysis revealed that minimum song frequency was highly predictive of a species' response to noise, with lower minimum song frequencies incurring greater noise‐associated reduction in abundance. These results suggest that anthropogenic noise affects some species independently of vegetative conditions, exacerbating the exclusion of some songbird species in otherwise suitable habitat. Minimum song frequency may provide a useful metric to predict how particular species will be affected by noise. In sum, mitigation of noise may enhance habitat suitability for many songbird species, especially for species with songs that include low‐frequency elements. 相似文献
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2010年10月至2011年9月期间,使用样线法对微山湖鸟类多样性进行研究.共发现鸟类132种,隶属13目39科,其中留鸟39种,夏候鸟33种,冬候鸟14种,旅鸟46种,分别占全部种类的29.6%、25.0%、10.6%和34.85%;国家二级保护鸟类有12种,省级重点保护鸟类16种,另外50种和16种鸟类分别列入中日、中澳候鸟保护协定.灰鹤、乌雕、沙鵖和白顶鵖4种鸟类在南四湖首次记录.根据微山湖的地理和植被状况,将研究区域划分为水域、次生林、农田和居民区4生境,不同生境中鸟类群落的Shannon-Wiener指数高低为沼泽水域>次生林>农田>居民区,Pielou指数高低为沼泽水域>农田>次生林>居民区.次生林和农田鸟类群落的相似性指数最高,沼泽水域与居民区的相似性最低.春季末期鸟类多样性指数和均匀性指数最高,秋季末期最低.冬季鸟类种类最多、密度最大,春初鸟类种类最少、密度最小.距居民区的距离、距公路的距离、植被盖度、人工池塘数目、水面积比例和深水面积比例等对鸟类多样性影响显著. 相似文献
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长江师范学院校园夏季鸟类群落与多样性分析 总被引:5,自引:0,他引:5
2008年3~7月采用样线法对长江师范学院李渡校园鸟类组成和种群数量进行了调查,共记录鸟类6目21科28种,数量1633只,物种多样性指数为3.9204,均匀性指数为1.1765,其中国家“三有”名录鸟类25种,CITES名录鸟类1种。鸟类区系以东洋界成分为主。对不同生境鸟类多样性的分析结果表明:(1)乔灌林鸟类多样性指数和均匀性指数最高,水域鸟类多样性指数最低,建筑区均匀性指数最低;(2)乔灌林与竹林的相似性指数最高,竹林与水域的相似性最低。 相似文献