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1.
2015年春季,利用样线法和样点法对小北湖自然保护区春季鸟类多样性进行研究。共记录到鸟类16目40科148种4904只,为小北湖国家级自然保护区记录鸟类种数的58.04%。雀形目鸟类种类和数量均最多,共68种3470只,占鸟类种数的45.95%,鸟类数量的70.76%。利用多样性指数和均匀性指数方法对小北湖保护区春季鸟类多样性进行了分析,其多样性指数为3.8877,均匀性指数为0.4575。从生境上分析,林地生境鸟类多样指数值为最高,水域生境最低;不同生境多样性比较:林地(3.3191)草甸(3.1073)灌丛(2.9531)沼泽(2.7129)水域(2.1868);均匀性指数则草甸生境最高,水域生境最低;均匀性比较:草甸(0.4592)沼泽(0.4543)灌丛(0.4465)林地(0.4417)水域(0.3484)。  相似文献   

2.
2012年4月10日-5月15日,在黑龙江珍宝岛国家级自然保护区对春迁徙水类多样性进行了调查,共记录到鸟类7目13科45种99567只次。共记录到国家级重点保护鸟类13种26899只。应用鸟类多样性公式对春季水鸟多样性进行了分析,其多样性指数、均匀性指数和物种丰富度指数分别为1.849641、0.336797、和0.00042。并对水域、沼泽、草甸和农田水鸟多样性进行了比较;结果表明其多样性为水域(1.791485)>沼泽(1.789785)>草甸(1.629579)>农田(0.098193);均匀性指数为草甸(0.701821)>沼泽(0.368422)>水域(0.330151)>农田(0.098193);物种丰富度指数为草甸(0.037313)>农田(0.003175)>沼泽(0.000951)>水域(0.00063。本研究为今后水鸟资源管理和濒危物种的保护提供了科学依据。  相似文献   

3.
经对三江平原湿地鸟类资源及生境的调查。该区有鸟类226种,分为水禽和林栖鸟,提出了保护和恢复湿地多样性的措施和建议。  相似文献   

4.
内蒙古图牧吉自然保护区春季迁徙水鸟多样性研究   总被引:1,自引:0,他引:1  
2011年4月5日~5月5日,在内蒙古图牧吉国家级自然保护区对春迁徙水类多样性进行了调查,共记录到鸟类7目13科45种99567只次。共记录到国家级重点保护鸟类13种26899只。应用鸟类多样性公式对春季水鸟多样性进行了分析,其多样性指数、均匀性指数和物种丰富度指数分别为1.849641、0.336797、和0.00042。并对水域、沼泽、草甸和农田水鸟多样性进行了比较;结果表明其多样性为水域(1.791485)>沼泽(1.789785)>草甸(1.629579)>农田(0.098193);均匀性指数为草原(0.701821)>沼泽(0.368422)>水域(0.330151)>农田(0.098193);物种丰富度指数为草原(0.037313)>农田(0.003175)>沼泽(0.000951)>水域(0.00063)。本研究为今后水鸟资源管理和濒危物种的保护提供了科学依据。  相似文献   

5.
三江平原不同生境小叶章种群分株形态响应及季节动态   总被引:2,自引:1,他引:1  
对三江平原3种不同生境下小叶章的主要形态因子进行了测定,结果表明,3种生境下小叶章的形态数量指标表现出极显著的差异。在生境内,典型草甸小叶章的表型性状的平均值在7月份达到最大;在沼泽、沼泽化草甸小叶章中,表型性状的平均值均在8月份达到最大。在生境间,表型性状的平均值由大到小依次为典型草甸小叶章〉沼泽化草甸小叶章〉沼泽小叶章。  相似文献   

6.
小叶章分株高度的季节动态:典型草甸和沼泽化草甸在8月末均达到最大值,沼泽在7月末达到最大值,而后缓慢下降。小叶章种群茎构件和叶构件生物量的季节动态在三个生境中均表现出较一致的变化规律,均自5月末开始,各生境的数量性状逐渐增加,至7月末达到最大值,而后逐渐下降,呈抛物线型。三个生境小叶章分株F/C值均具有相似季节变化趋势。其极大值均出现在7月末,但三个生境之间亦有明显差异, F/C值的整体水平表现为沼泽>沼泽化草甸>典型草甸,其极大值、极小值亦反映出此规律。  相似文献   

7.
达赉湖自然保护区湿地生物生境保护   总被引:3,自引:0,他引:3  
达赉湖自然保护区保存了最完整的湿地生态系统和野生生物特有的遗传性,是我国重要的天然基因库之一;该区具有高等植物649种,隶属于71科,脊椎动物共有357种,隶属于64科,其中国家Ⅰ级保护鸟类7种,国家Ⅱ级保护鸟类42种,国家Ⅱ级保护哺乳类2种;自然条件和人为干扰导致的湿地污染以及对生物的驱逐效应的不断加剧,使该区生物面临着巨大的危险;从湿地生境安全保护的角度,提出了维持达赉湖自然保护区湿地生物多样性及其安全栖息生境的保护对策。  相似文献   

8.
一一 完达山区的红松林 针阔混交林下的刺五加liiiiiilliiiseONilliiliii 重沼泽区 沼泽河流 (傅承刽摄)———— 灌丛小叶樟沼泽化草甸 小叶樟草甸破坏后的撂荒地三江地区自然景观  相似文献   

9.
同仁县多哇等七乡的高寒草甸、灌丛草甸草地均有虫草分布,蕴藏量约1.4万公斤。为保护虫草资源,今后应制定年度采挖计划,限制外来人员采挖,实行虫草采集证制度,教育虫草采挖人员按要求采挖,加强虫草资源保护和采挖的监管力度  相似文献   

10.
本文利用野外调查数据,通过影子价格法、碳税法对黄河源区原生草地碳储量及严重退化草地碳储量进行对比,结果显示黄河源区原生草甸碳储量为1248.17g/m2,固碳价值0.27RMB/m2,严重退化草甸碳储量423.84 g/m2,固碳价值0.09 RMB/m2,原生灌丛碳储量为1359.54 g/m2,固碳价值0.28 RMB/m2,严重退化灌丛碳储量为1088.17g/m2,固碳价值0.22RMB/m2,其理论价值:黄河源区草甸碳储量是影响植被碳储量的重要因子,应用价值:固碳价值为研究区生态补偿标准提供一定的参考意义。  相似文献   

11.
Granivorous birds, mainly the Red‐billed Quelea, have subsisted on cereal crops in Africa for centuries and have caused substantial damage. There is, however, limited recent evidence on their impact. We propose an indirect method to estimate bird‐inflicted crop losses by fitting a production function with a damage abatement component and pest intensity slope dummies on a panel database of rice farmers in the Senegal River Valley. This allows us to estimate both bird damage and marginal productivity of bird control at different levels of bird pressure. Annual bird damage is found to average around 13.2% of the potential rice production during the wet seasons of 2003–2007, which translates into an average annual economic loss of 4.7 billion FCFA (€7.1 million). Our results are consistent with farmers’ perceived bird‐inflicted crop losses, averaging 15.2%. More alarmingly, we observe declining marginal productivities of bird control under increasing bird pressure. Farmers indicate that at high bird pressure, the efficacy of traditional bird scaring methods is inadequate, which suggests that predictive (monitoring), preventive (population control) and protective (insurance) measures against massive invasions are more urgent than improving the average efficacy of curative measures (pest control). These findings are especially relevant to farmers and policy‐makers who are currently struggling to implement an ambitious food self‐sufficiency programme in Senegal.  相似文献   

12.
扎龙自然保护区的3条观鸟路线共观察记录鸟类66种,其中国家Ⅰ级保护鸟类3种,Ⅱ级7种,省级保护鸟类5种;夏侯鸟49种;古北界种类45种、广布种19种、东洋界2种。路线A的鸟类多样性最高。路线B是比较理想的早春观鸟路线。  相似文献   

13.
孔林内有鸟类31种。隶属9个目;可划分为4种鸟类群落,落叶阔叶林-大山雀+小蝗莺+黑枕黄鹂群落;针阔混交林-大山雀+灰喜鹊+小蝗莺群落;针叶林 -夜鹭+大山雀+金翅雀+山斑鸠群落;杂灌林-灰喜鹊+大山雀+金翅雀+黑枕黄鹂群落;提出了对孔林植物和鸟类资源保护的对策。  相似文献   

14.
根据在东洞庭湖湿地实地实时调查,共鉴定鸟类2 172只,合计23种,隶属6目14科;东洋界鸟类7种,古北界鸟类1种,广布种鸟类15种,在区系上以东洋界鸟类为主;冬候鸟、留鸟分别为16种、7种,在居留型上,主要以冬候鸟居多。该区鸟类平均密度为158.9只/hm2,多样性指数为2.426467,均匀性指数为0.773871。多年来由于自然因素以及人类不合理的开发利用活动,东洞庭湖湿地野生鸟类资源面临许多生态威胁;指出了东洞庭湖湿地野生鸟类资源面临的生态问题,并提出了相应的保护对策。  相似文献   

15.
Increasing pressure on extensive farming systems in marginal areas requires them to become more resilient and adaptable to extreme conditions brought about by climate change. Yet these rangeland areas must also be protected as refuges for biodiversity and as important carbon stores. Recent United Kingdom policy initiatives are encouraging the use of traditional or native breeds of livestock to preserve genetic diversity, due to their perceived adaption to harsh environments and their value for managing extensive habitats for conservation. It is not clear however, whether these benefits are based on scientific evidence or perhaps more on current opinion; nor whether farm system practices are likely to change in response to these initiatives. This study offers an approach that can support future empirical studies designed to better inform such policy decisions.A survey was carried out to provide insight into current opinions regarding the impacts of cattle on hill environments and the cattle breeds appropriate for hill environments, before more detailed farm interviews provided data for a characterisation of suckler beef farming systems in Scotland using a typological approach. Survey results indicated that the majority of respondents believed cattle have a positive effect on hill environments when carefully managed, yet there was wide diversity in opinion regarding the type of impacts and most suitable breeds. Interview results highlighted the diversity of management systems, decision making processes and cattle types present and indicated significant variation in farmers’ views regarding breed hardiness, suitability and reasons for their choice of breed. Three system groups: Traditionalists, Improvers and Production optimisers, were clearly defined by the typology, with significant variation observed in their management practices and views. This study suggests that hill beef farmers appear to not only adapt their production systems according to their current bio-physical and financial circumstances, but also from personal experience. Accumulation of this kind of evidence is long overdue and could provide support to the development of any future policies regarding cattle and hill environments.  相似文献   

16.
This article presents a mathematical programming approach to determine a conservation strategy that maximizes preserved species' diversity under limited resource availability. Diversity is defined as the negative of total diversity loss given by the sum of genetic distances between extinct species and their closest surviving relatives. The model incorporates both species richness and genetic diversity as the conservation criteria when determining species preservation and site selection decisions. The article also presents two empirical applications to the conservation of 15 crane species and 208 genera including most of the endangered or threatened North American bird species.  相似文献   

17.
This article investigates the effects of wheat genetic diversity and land degradation on risk and agricultural productivity in less favored production environments of a developing agricultural economy. Drawing production data from a household survey conducted in the highlands of Ethiopia, we estimate a stochastic production function to evaluate the effects of variety richness, land degradation, and their interaction on the mean and the variance of wheat yield. Ethiopia is a center of diversity for durum wheat and farmers manage complex variety mixtures on multiple plots. Econometric evidence shows that variety richness increases farm productivity. Variety richness also reduces yield variability but only for high levels of genetic diversity. Simulations with estimated parameters illustrate how planting more diverse durum wheat varieties on multiple plots contribute to improving farmer's welfare.  相似文献   

18.
Recent decades have witnessed substantial losses of biodiversity in Europe, partly driven by the ecological changes associated with intensification of agricultural production. These changes have particularly affected avian (bird) diversity in marginal areas such as the uplands of the UK. Future trends for upland birds will likely be impacted by changes in agricultural support regimes, such as those currently envisaged in on-going reforms of the Common Agricultural Policy. We developed integrated ecological-economic models, using seven different indicators of biodiversity based on avian species richness and individual bird densities. The models represent six different types of farms which are typical for the UK uplands, and were used to assess the outcomes of different agricultural futures. Our results show that the impacts of these future agricultural scenarios on farm incomes, land use and biodiversity are very diverse across policy scenarios and farm types. Moreover, each policy scenario produces un-equal distributions of farm income changes and gains and losses in alternative biodiversity indicators. This shows that generalisations of the effects of policy and pricing changes on farm incomes, land uses and biodiversity can be misleading. Our results also suggest that a focus on umbrella species or biodiversity indicators (such as total species richness) can miss important compositional effects.  相似文献   

19.
At a global level, increasing emphasis on sustainable development highlights the importance of maintaining and enhancing biodiversity. Within the European Union, agricultural reforms will have a considerable influence on the links between biodiversity, agriculture and rural communities over the next 10–20 years. An understanding of the associations between biodiversity and the rural economy is important for the development of policies to promote environmentally sustainable economic and social well‐being. However, investigations of this type are frequently hindered by the different ways in which data in the natural and social sciences are collected. In this paper, we develop an innovative approach to combine data using a common spatial unit. We illustrate the application of this approach by examining associations between bird species richness, environmental and socio‐economic variables. Our results show how the statistical relationship between biodiversity and environmental factors is strengthened and contextualised by prevailing socio‐economic conditions. This example highlights the additional insights that can be gained from such an integrative approach, especially in terms of the questions it raises about the inter‐relationships between the social, physical and ecological dynamics of rural environments.  相似文献   

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