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DAVID BAINES 《Ibis》1994,136(1):39-43
Between-season differences in habitat use by Black Grouse Tetrao tetrix were studied on four moors in the northern Pennines between 1989 and 1992. Heather moor and bogs were preferred at all times of the year, apart from during the breeding season. In spring, large quantities of Cotton-grass Eriophorum vaginatum flowers were consumed, whereas in autumn and winter Heather Calluna vulgaris was more important. Enclosed fields on the edge of the moors were regularly used in autumn and winter by large flocks of cock birds, and hens were found in smaller groups. Where present, overgrazed grass moorland was generally avoided, apart from during the summer. Similarly, enclosed rough grazing allotments rich in rushes were favoured during the summer months by breeding hens and moulting cocks.  相似文献   

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Summary

The term machair is commonly applied to the landform/vegetation systems of many dune pasture areas of parts of the Highlands and Islands of Scotland. Definition of such areas appears to rest on locational, morphological, vegetational and soil criteria. Closer examination suggests that the main diagnostic feature is the soil parent material, shell-rich blown sand, which gives rise to high calcium carbonate and pH conditions. Secondary criteria include the morphological maturity of the machair surface, the absence of depositional processes, specific plant associations (notably the elimination of long dune grasses) and a history of grazing and, possibly, cultivation. Machair areas must also be set in a cool, moist maritime climatic regime.  相似文献   

4.
藏北高寒草地植被的碳密度与碳贮量   总被引:4,自引:0,他引:4  
采用实地调查与查阅文献相结合的方法估算藏北高寒草地植被碳密度和碳贮量。结果表明:1)藏北高寒草地总面积约39.059×106 hm2,植被地上平均碳密度12.158±4.7g·m-2,植被地下平均碳密度84.458±20.38g·m-2,植被地上部碳贮量5.171±0.95Tg,植被地下部碳贮量25.223±2.96Tg,植被总碳贮量为30.394±3.91Tg;2)不同草地组间植被碳密度和碳贮量差异显著。其中不同草地组间植被碳密度以丛生禾草组碳密度值最低,地上和地下碳密度分别为6.13±1.51g·m-2和26.04±5.8g·m-2,具灌木的半灌木组碳密度最高,地上和地下碳密度分别为31±3.4 g·m-2和244.59±6.9g·m-2;而不同草地组间,草地植被碳贮量以小莎草组最大,植被地上和地下碳贮量分别为2.24±0.32Tg和9.52±0.89Tg,半灌木组碳贮量最小,其地上和地下碳贮量分别为0.012 4±0.002Tg和0.098 1±0.002Tg。3)藏北高寒草地分布各县(区)碳密度和碳贮量的分布也存在显著差异。从碳密度来看,革吉县、札达县、噶尔县和措勤县碳密度较高,植被平均碳密度分别相当于藏北平均植被碳密度的1.76,1.47,1.11和1.06倍,从碳贮量来看,碳贮量集中分布于双湖特别区、札达、尼玛、日土、革吉和改则6县(区),六县(区)草地植被碳贮量为25.2±2.31Tg,占藏北总植被碳量的82.89%。  相似文献   

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河南黄河湿地国家级自然保护区孟津段水鸟资源调查   总被引:3,自引:0,他引:3  
1995~2008年,对河南黄河湿地国家级自然保护区孟津段水鸟资源进行了调查,共记录水鸟98种,隶属8目18科.其中国家Ⅰ级保护水鸟2种,国家Ⅱ级保护水鸟12种.根据居留类型,本区有冬候鸟41种,夏候鸟32种,旅鸟16种,留鸟9种.从分布型区分,古北界鸟类63种(占64.3%),东洋界鸟类5种(占5.1%),广布型鸟类30种(占30.6%),区系组成呈现南北鸟类混杂分布、以古北界鸟类为主的特征.  相似文献   

6.
以国家公园为主体的保护地体系管理机制的构建   总被引:1,自引:0,他引:1  
赵金崎  桑卫国  闵庆文 《生态学报》2020,40(20):7216-7221
十八届三中全会提出"建立国家公园体制"以来,关于国家公园试点区、机构体制改革等方案相继推出,国家公园的建设稳步进行着。从机构设置、权力配置以及运行机制三个方面探讨以国家公园为主体的保护地体系管理机制的构建。分析发现:国家林业和草原局的设立使得国家公园有了统一的管理机构;先前多部门的职能被重新整合,权力的上交和流转、日趋完善的监管机制极大地促进了国家公园体制的建设。结合国外经验,得出我国在国家公园管理机制的构建中应重视基层机构的设置、监督机制的加强以及法律法规的完善等结论。并且对生态补偿以及多样化的管理方式做出了展望。  相似文献   

7.
Data from the long-term experiment on sheep grazing versus zero sheep grazing (i.e. in an enclosure) on the composition of the Juncus squarrosus grassland at the Moor House NNR are presented. The data have been analysed to assess change in (1) the abundance of individual species, (2) higher plant and bryophyte communities, and (3) vegetation structure. The higher plant data suggested that both the enclosed-and grazed plots were changing in the same direction, but the enclosed plot was moving much faster. The general tendency was towards a blanket bog vegetation dominated by Eriophorum vaginatum and Calluna vulgaris. Juncus squarrosus has declined very quickly in the enclosed plot, but there has also been a slower decline in the grazed one. A significant increase in Calluna vulgaris has occurred only in the enclosed plot. In contrast, the bryophyte data showed completely different successional trajectories in the two treatment plots.The vegetation structure changed markedly after release from grazing, with a decrease in phytomass, but increase in necromass in the lowest height strata. There was no noticeable change in structure over the 18 year period in the grazed plot.Particular problems found in this study were that some species either fluctuated widely in response, or changed in a curvilinear manner.  相似文献   

8.
周繇 《生物学通报》2004,39(8):18-19,F003,F004
金凤蝶(papilio machaon)(本文照片见封三、封四)形态特征:翅展75~95mm,大型,翅面金黄色。前翅基部1/3为黑色。外缘具有1条黑色宽带。后翅外缘有6个黄色新月斑,臀角有1橙色圆斑。生态:1年2代。春型5~6月,体型较小;夏型7~9月。体型较大。♀比♂的黄色较淡,卵圆球形,以蛹越冬。寄主植物是伞形花科的独活、柴胡等;芸香科的黄檗、白藓等。分布的区域为海拔700~1589m。  相似文献   

9.
The need for a scientifically based wildlife management plan and more knowledge on the vegetation ecology of the Borakalalo Nature Reserve prompted an ecological investigation of the Reserve. One of the aims was to develop a structural classification of the woody component using species size (SPIZE) classes. A further aim was to compare the various structural classes identified with the recognized floristically derived plant communities of the Reserve. The frequency, density, percentage crown cover and importance value for each woody species were calculated. A classification of the woody component was done using a TWINSPAN classification algorithm on this structural density data. Fifteen structural SPIZE classes were identified, described and compared with the described plant communities. The results of this study indicate that structural SPIZE classes could also be used to explain the spatial distribution of woody species within and between various plant communities.  相似文献   

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美姑大风顶自然保护区种子植物区系分析   总被引:7,自引:1,他引:7  
四川美姑大风顶国家级自然保护区有种子植物 1 1 8科 ,3 85属 ,860种 ,其中裸子植物 5科 ,1 6属 ,1 9种 ;被子植物 1 1 3科 ,3 69属 ,841种。种子植物属、种的区系成分共有 1 3个类型 ;在所有成分中 ,以温带区系成分为主 ,达 1 81属 ,占总属数的 5 1 .5 8%。中国特有分布属共 1 1属 ,占总属数的 3 .1 3 % ;中国特有分布种共41 0种 ,占总种数的 48.41 %。保护区共有珍稀濒危植物 1 8种 ,其中国家一级保护植物 4种 ,国家二级保护植物 6种 ,国家三级保护植物 8种。  相似文献   

12.
2006年9月~2007年8月,对河南黄河湿地国家级自然保护区鸟类进行野外调查,结合文献共统计鸟类16目53科247种.对山地、滩地、水域、人工林4种生境鸟类物种数、鸟类数量等级、多样性、鸟类群落间相似性进行了分析.滩地鸟类物种数及G指数(属的多样性)和F指数(科的多样性)值均最高.山地和人工林鸟类组成有相似性.  相似文献   

13.
天目山自然保护区悬钩子属药用植物资源研究   总被引:5,自引:0,他引:5  
田春元  周秀佳 《广西植物》2004,24(4):297-301
通过野外调查、采集标本、分类鉴定和查阅文献相结合的方法对浙江省天目山国家级自然保护区悬钩子属植物的药用资源状况进行了较为系统的调查研究。结果发现 :该保护区有悬钩子属植物 1 6种和 1变种 ,它们都可以作为药用植物入药 ,且资源蕴藏量大 ,具有较高的开发利用价值。该项研究有助于该保护区悬钩子属药用植物的开发利用 ,对扩大该属植物药源和发展地方经济都将起到积极的促进作用  相似文献   

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小秦岭自然保护区秦岭冷杉死亡原因   总被引:3,自引:1,他引:3  
小秦岭国家级自然保护区濒危植物秦岭冷杉(Abies chensiensis)近几年出现了不明原因的衰败死亡现象,并有不断扩展的趋势,分析研究就地保护这一珍稀植物资源迫在眉睫。在对小秦岭全部秦岭冷杉定位监测的基础上,通过对活树、死树分布和结构的对比分析,并采用相关分析、偏相关分析和结构等式模型(Structural Equation Models,SEM)结合环境因子,探讨了秦岭冷杉的生存状况和死亡原因。结果如下:(1)枯死树与活树分布基本相一致,活树个体中小树和大树相对较少,死亡个体主要为小树和中龄树;(2)秦岭冷杉的生长与海拔、坡度、土壤含水量和土壤温度呈显著的相关性;(3)SEM分析结果显示,秦岭冷杉活树与土壤含水量和温度呈明显的正相关系,而死树却表现出负相关关系,枯死树与空间位置和地形表现出的负相关关系要明显大于活树。上述结果说明,秦岭冷杉幼苗和小树较少,更新能力差,秦岭冷杉的死亡不是个别现象和局部环境变化所造成的;秦岭冷杉的生长与海拔、坡度、土壤含水量和土壤温度关系密切;土壤含水量和温度对秦岭冷杉生长具有促进作用,是影响秦岭冷杉死亡和衰败的重要环境因素。在今后秦岭冷杉经营保护过程中要注意微环境的变化,减少人为因素对环境的干扰。  相似文献   

17.
Nature reserves (NRs) play a pivotal role in minimizing habitat loss and protecting wild animals and plants, which are critical for human ecological security. However, focusing only on the construction of ecological security patterns of NRs without understanding their ecological security early-warning situations and their driving factors may fail to achieve protection goals. This study constructed an ecological security early-warning framework and index system based on the Driving force-Pressure-State-Impact-Response (DPSIR) framework model. The gray model (GM) was used to predict the ecological security early-warning situation, and the Geo-detector model was applied to explore the driving factors of the ecological security early-warning system in the Baishuijiang National Nature Reserve (BNNR). The results showed that the average ecological security index (ESI) value increased from 0.2796 in 2005 to 0.3171 in 2017, with an average increase of 11.82%. The ecological security early-warning index (ESEWI) value increased from 0.3171 in 2018 to 0.3622 in 2030, which was an average increase of 12.46%. These results indicated that the ecological security situation continually improved from 2005 to 2030. By 2030, the number of towns with a “no warning” grade increased to four, the number of towns with an “extreme warning” grade was zero, and the proportion of areas with early-warnings decreased from 100% to 33%. The q values of per capita forest land areas and per capita grassland areas were both 0.9334, which indicated that environmental characteristic factors were the primary driving factors in ecological security early-warning. Our results demonstrated that the ecological security early-warning index system based on the DPSIR model and grey model can well prediction ecological security situation and provide scientific support for the ecological protection and management of NRs.  相似文献   

18.
<正>花湖的湖岸已经退却了50多米,水面下降了近1米。1976年,年轻的扎科作为青年突击队长,带领乡里几百个青壮劳力在若尔盖的沼泽地里开沟修挖排水渠。沼泽里的水很深,藏语称根没,意为无底的。据扎科回忆,当时沼泽的水深到用12米的绳子吊一个秤砣  相似文献   

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朱华  杜凡 《生物多样性》2022,30(3):21519-348
滇西北丽江-宁蒗北纬27°的金沙江干热河谷具有大面积的原生性萨王纳植被, 是云南最北的连片分布的萨王纳植被类型, 被认为是世界萨王纳植被的干热河谷残存者, 也是我国一类珍稀濒危的植被。它包含特有单种属菊科乔木栌菊木(Nouelia insignis)群落, 在沟箐和局部地段, 还存在典型热带季雨林树种白头树(Garuga forrestii)占优势的群落, 这些情况非常罕见。该地区植物区系特殊, 生物多样性丰富, 生态系统完整, 在科学研究和自然保护上具有重要价值, 符合建立自然保护地的条件, 建议设立为保护金沙江干热河谷萨王纳植被的自然保护地(区)。  相似文献   

20.
Holocene sediments of three closed Danish lake basins (Solsø, Skånsø, Kragsø) were used for the inference of post-glacial vegetational dynamics in former heathland areas in northern West Jutland, Denmark. The sites were selected to represent the major geomorphological units of West Jutland. The Holocene history of each lake basin was investigated by mapping of sediment distribution, analysis of loss-on-ignition, coarse inorganic matter, humus content, mineral magnetics, δ13C, pollen and selected other microfossils. These techniques were supplemented by plant macrofossil analysis at one site. Holocene terrestrial vegetational development was inferred at each site from analyses of pollen and microscopical charred particles. Chronologies were provided by numerous 14C dates. Stratigraphies of wet ground and terrestrial pollen and spore types were zooned by stratigraphically constrained cluster analysis. Based on the resultant site pollen asemblage zones (site PAZ), regional PAZ were proposed. Using modern analogues, Holocene floristic richness was estimated from pollen richness in the microfossil assemblages. The results support the hypothesis that disturbance is one of the most important mechanisms behind the maintenance of floristic richness. In particular, the response of estimated floristic richness to the intensity of vegetational fires followed the predictions of the Intermediate Disturbance Hypothesis. A period of elevated palynological richness and inferred vegetational disturbance was identified at all sites between 6000 and 5200 BC (calendar years). Using correspondence analysis (CA), the major gradient in the terrestrial pollen sequences was identified as a light-shade gradient, and CA first axis sample scores were used as a supplement to standard AP/NAP pollen ratios as an indicator of the shade-tolerance/light-demand of Holocene terrestrial plant communities. In spite of different vegetational developments since 4000 BC, the timing of major changes towards more light-demanding vegetation types were broadly synchronous at the three sites. Using chord distance as a dissimilarity index, rales of palynological change suggest that the interval between 8000 and 7500 BC (calendar years) was the period of most rapid vegetational change during the Holocene, both in terrestrial as well as lacustrine ecosystems. While climatic forcing of the rapid events around 8000 BC is hypothesised, the synchronous timing of relatively rapid inferred change in lake and terrestrial vegetation around AD 600 may reflect changes in climate as well as in land-use. Reducdancy analysis was used to develop a model between fire intensity (inferred from microscopical charred particles) and vegetational response, as reflected by pollen assemblages. Formulated at one site and tested at the two other sites, the model explains regional Colluna-heathland expansions as a result of vegetational burning. Similarly, declines in heathland cover are explained by lack of maintenance by fire. Regional vegetational development in northern West Jutland is reconstructed and special consideration is given to heathland history. The Holocene heathland development is interpreted as resulting from its importance for grazing. It is hypothesized that on poor soils, Calluna-dominated heathland was a better grazing resource than grass-dominated pasture, due to the winter-grazing offered by Calluna and the low palatibility of dominant grasses on poor soils. This hypothesis is relevant for the explanation of the variation in timing of heathland expansions on the different soil types represented by the study sites.  相似文献   

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