Effects of prescribed burning on distribution and abundance of birds in a closed-canopy oak-dominated forest, Missouri, USA     

John G. Blake 《Biological conservation》2005,121(4):519-531

Prescribed, biennial burning in forest understory started in Cuivre River State Park, Missouri, USA, in the late 1980s to help restore the forest to conditions that existed prior to European settlement. Bird surveys were started in 1996 on two burned and two unburned sections of the park to determine what effects the burning and subsequent changes in vegetation were having on bird populations. Birds were sampled at 17 60-m radius point counts on each study area; each point was sampled twice per year during the main breeding period from 1996 through 2002. Total abundance and species richness differed among the four areas but no differences could be attributed to burning. Some individual species, however, differed in abundance and frequency of occurrence between burned and unburned areas. For example, Indigo Bunting (Passerina cyanea), Kentucky Warbler (Oporornis formosus), and several species of woodpeckers were more abundant on burned areas; Ovenbird (Seiurus aurocapillus), Worm-eating Warbler (Helmitheros vermivorous), Wood Thrush (Hylocicla mustelina) and Acadian Flycatcher (Empidonax virescens) were among the species more abundant on unburned areas. As a consequence, overall community composition differed significantly between burned and unburned areas of the park, but did not differ between burned areas or between unburned areas. Prescribed burning was instituted to restore vegetation to presettlement conditions and has started to achieve that objective. Restoration also has affected and likely will continue to affect bird populations. Future maintenance of a full complement of bird species, including a number of neotropical migrants, will be dependent on presence of both burned and unburned forest habitat.  相似文献   

南滚河自然保护区鸟类系分布研究     

刘宁  张庆 《东北林业大学学报》1999,27(4):49-52

经调查．在南滚河保护区共记录到鸟类１４７种和亚种．隶属１４目．３６科另４亚科．约占云南省鸟类种数的１８．４％。在实地考察和综合前人资料的基础上、对南滚河自然保护区的鸟类进行了区系和生境分析及资源评价．并提出了保护和开发的建议。  相似文献   

影响长输管道安全的隐患及对策   总被引：4，自引：0，他引：4  

何悟忠  郭庆茹  董仲智 《油气储运》2001,20(4):50-52

论述了影响长输管道安全的主要隐患，以东北管道为例进行了分析认为隐患形成的原因主要来自环境的影响，人为因素的破坏和输送工艺变化的影响等，列举了东北管道安全隐患的分布状况，并提出了杆绝安全隐患的基本对策。  相似文献   

Fragmentation and wildlife in montane evergreen forests, northern Thailand     

Anak PattanaviboolPhilip Dearden 《Biological conservation》2002,107(2):155-164

Montane evergreen forests in northern Thailand are high in biodiversity and becoming increasingly fragmented. We studied fragmentation and wildlife response in two contiguous wildlife sanctuaries. Om Koi still maintained relatively large patches (>400 ha) with some connectivity while Mae Tuen was comprised mainly of small and isolated patches (<100 ha). Mae Tuen lost 2640 ha of montane evergreen forest between 1954 and 1996 compared to a loss of 888 ha in Om Koi. We compared the wildlife between four forest patches in Mae Tuen, with four in Om Koi finding nine mammals and 89 birds in Mae Tuen and 19 mammals and 119 birds in Om Koi. Om Koi still supports populations of large mammals and frugivorous birds extirpated in Mae Tuen. The results document the high rate of fragmentation in protected areas that often interact synergistically with other pressures to reduce biodiversity.  相似文献   

广东连南板洞省级自然保护区鸟类多样性初步调查     

吴书德  唐刚  佟富春 《广东园林》2022,(3):13-16

鸟类多样性研究是自然保护区的重要工作之一。2021年1—12月,采用样线法和样点法,调查了广东连南板洞省级自然保护区鸟类多样,共记录到鸟类15目54科211种。其中国家Ⅰ级和Ⅱ级重点保护鸟类分别为2种和34种;区系以东洋界为主,有129种（61.72%）,古北界44种（21.05%）。居留型以留鸟为主,有136种（65.07%）,冬候鸟40种（19.14%）。优势种为栗颈凤鹛Staphida torqueola和淡眉雀鹛Alcippe hueti;常见种和少见种分别 为27种和59种。Shannon-wiener多样性指数、Marglef丰富度指数、Pielou均匀度指数和Simpson指数计算结果均为板洞保护站最高。该保护区是每年大批鹭鸟等候鸟迁徙的必经路线,建议加大监测力度,掌握候鸟变化动态等。  相似文献   

国产LRH-A穴位注射治疗奶牛不孕症的研究     

郁国  陈志森  潘新权 《上海交通大学学报(农业科学版)》1989,(4)

本研究系采用中西兽医结合的方法,首次应用国产LRH-A穴位注射后海穴、百会穴和催情穴(任选一穴)治疗因卵巢机能失调所造成的不孕症奶牛共177例,总有效率达73.6～100％,与肌肉注射疗法比较,提高疗效10.7％左右,用药量比肌肉注射节省2/3～4/5,取得了满意效果。在探索其治疗机理方面,测定了血浆中孕酮(P)和17β一雌二醇(E_2)的含量变化,提供了一定依据。  相似文献   

Bird diversity and the conservation value of a new Ramsar site: Guangdong Haifeng Wetlands,China     

Junhua HU  Zhigang JIANG  Chunlan ZHANG  Feng XIAO  Huijian HU 《Integrative zoology》2011,6(3):266-278

Wetlands are critical habitats for birds. However, wetlands are being degraded at an accelerating rate due to global human activity, and a disproportionate fraction of wetland‐dependent bird species are in decline. We evaluated the conservation value of a new Ramsar site, Guangdong Haifeng Wetlands, China, for birds, by comparing bird communities (using line transect data) in 3 different districts: Gongping, Dongguan Lian'anwei and Dahu. We recorded 139 species of birds, including 26 species that are protected at a national level. Dahu had the highest species richness and diversity, whereas Dongguan Lian'anwei had the highest abundance of birds and the lowest species diversity. Finally, Gongping had both the lowest species richness and the lowest abundance. The endemism of constituent species differed among districts, and the bird communities were complementary. There were significant seasonal differences in the species richness and the number of individuals. Spring had the highest species richness and diversity. The present study identifies the high conservation value of Haifeng Wetlands for both waterbirds and terrestrial birds. Our findings suggest that conservation efforts in Haifeng Wetlands and other wetlands should focus not only on wintering migratory birds, but also on resident birds. To accomplish effective conservation, we should consider the reserve and surrounding wetlands as a whole, incorporating ecological research, education and local economic development.  相似文献   

Misleading results from conventional gap analysis – Messages from the warming north     

Heini Kujala  Miguel B. Araújo  Wilfried Thuiller  Mar Cabeza 《Biological conservation》2011,(10):2450-2458

Gap analysis is a widely used method for assessing the representation of species in protected area (PA) networks. However, representation does not imply persistence. Here, we investigated whether gap analysis may result in misleading conservation guidelines by comparing the representation to two indicators of persistence. We ran a gap analysis with Finnish breeding birds and identified conservation priorities based on current distribution patterns. We tested the sensitivity of these results by using two target setting schemes and several thresholds defining the amount of protected area, and found the levels of representation identified by gap analysis to be robust. We then compared the gap analysis results with recent population trends and projected changes in potential suitable climate under different climate change scenarios for the year 2050. We show that although high latitude species are well represented in PAs, they are currently declining and are projected to lose climatic suitability in the near future. In contrast, low latitude species with poor representation in PAs have increasing population trends and are generally expected to expand their ranges into protected areas in the near future. This study demonstrates with empirical data a mismatch between representation in PAs and population trends, resulting in misleading understanding of current PA effectiveness. The mismatch is linked to the latitude of species distributions and corresponds to expected future changes, indicating that the patterns are potentially driven by climate change. We therefore urge practitioners and researchers to include better indicators of persistence in gap-analysis frameworks even for short term assessments.  相似文献   

Hurricane Katrina impacts the breeding bird community in a bottomland hardwood forest of the Pearl River basin, Louisiana     

David R. Brown  Thomas W. SherryJames Harris 《Forest Ecology and Management》2011,261(1):111-119

We monitored breeding bird communities and vegetation both before and after Hurricane Katrina category 2 winds severely damaged extensive bottomland hardwood forest of the Pearl River basin, south Louisiana. Many trees were felled by wind, most others were stripped of leaves and branches, and the canopy opened considerably (57%). Blackberry thickets sprouted and expanded to cover almost all of what was previously a patchily open forest understory. The bird community changed distinctively following the hurricane, driven primarily by increased density of species that prefer dense understory (regenerating) habitat. Individual species that increased significantly in density included one year-round resident, Carolina wren, and five breeding migrants, white-eyed vireo, Swainson's warbler, Kentucky warbler, hooded warbler, and yellow-breasted chat. These patterns were predictable responses to the opened canopy and increased density of understory vegetation. However, over three years following the storm, most species, especially canopy breeders, showed no distinct numerical response to the hurricane, which suggests that the initial bird community was resistant to hurricane disturbance. Only one species, Acadian flycatcher, declined significantly after the hurricane, presumably because of loss of its preferred open understory breeding and feeding habitat. Our results thus document and reinforce the important role hurricanes play along the Gulf coast in structuring forest bird communities by altering understory habitat. We expect habitat changes will continue as invasive plant species further change forest community structure, and as large storms increase in frequency in relation to global climate change. Thus, we also expect continued changes to the bird community, which may include additional future declines.  相似文献   

Extinction rates, extinction-prone habitats, and indicator groups in Britain and at larger scales     

Clive Hambler  Peter A. Henderson  Martin R. Speight 《Biological conservation》2011,(2):713-721

We present the first detailed comparison of extinction rates amongst a wide range of nonmarine groups, using data from Britain. For selected taxa, comparisons are made with rates in the United States and the globe. We estimate the overall extinction rate in Britain is 1–5% of the regional species list per century. Most of the groups of organisms assessed have very similar rates, with high rates in some groups which are aquatic, use dead wood or are on their climatic margin. In Britain, the extinction rate probably rose from the 19th to the 20th Century, and is projected to rise in the 21st Century. Habitat loss is the principal driver of extinctions. In Britain, birds are relatively good indicators of extinction rates and extinction-prone habitats, whilst butterflies are not. At larger scales, such as the USA and globally, birds, freshwater fish and amphibians show potential as indicators. Consideration of ‘Possibly Extinct’ species and monitoring of habitat area may provide more responsive measures of biodiversity loss.  相似文献