1.Alpine meadow and wetland,closely correlated with the amount of water stock in the riverhead of China,is the most important ecosystem of the Qinghai-Tibetan Plateau.This ecosystem is the primary support for the industrial and agricultural and the living using water in the middle east of China,which makes the conservation of alpine meadow and wetland in the Qinghai-Tibetan Plateau have importantly practical significance.This paper presents the composition structure of plant biodiversity in Maqu,a county of Gannan Tibetan Autonomy Prefecture and located at the northeastern edge of the Qinghai-Tibetan Plateau,which is the riverhead of the Yellow River.With the analytic hierarchy process,the reasons of deterioration and the measurers of restoration are given.By the competition theory of metapopulation,we have also presented the underlying mechanism of the maintenance of biodiversity in this region.Results show there are two contradictions between biodiversity conservation and improvement of meadow quality,and between local economic and social development and meadow quality maintenance.The first contraction suggests that high species richness needs moderate artificial and natural disturbance,which can create some patches in the habitat.These patches will be the temporal reproducing locations for pioneer species that primarily consist of low-quality ruderal,and will cost some patches for high-quality fodder.Secondly,the increasing of artificial disturbance,as a directly result of economic and social development,will be disadvantage to the maintenance of high-quality meadow and might exclude some dominated species,which will restrict the development of local animal husbandry.
高寒草甸及湿地是青藏高原上最为重要的生态系统,它的状况直接关系到我国江河源头的蓄水量,也关系到我国中部和东部广大地区的工农业及人民生活用水,因此对青藏高原高寒草甸与湿地的保护具有重要的现实意义.本研究对青藏高原东北缘黄河源头地区甘南藏族自治州的玛曲县高寒草甸及湿地进行调查,揭示了该地区的植被生物多样性情况与组成结构,利用解析层次方法分析了高寒草甸及湿地的退化原因及恢复手段,同时还从集合种群竞争原理出发对该地区植被生物多样性的维持机理进行了讨论.结果显示出两个现存的主要矛盾:在生物多样性保护与高寒草甸质量提高方面存在矛盾;在地区发展与高寒草甸质量提高方面也存在矛盾.前者表明为了提高物种多样性,必须存在一定干扰,包括人为干扰与自然生态系统干扰,这些干扰会在高寒草甸中形成一定数量的空斑块,这些空斑块为先锋种的繁殖提供了暂时的场所从而使多样性得到提高与维持.但由于先锋种普遍为杂草类而非优良牧草,因此这种多样性维持只能以牺牲草甸质量为代价.第二个矛盾说明为了提高当地经济与社会发展,必然会增加人为干扰,而这些干扰会首先对优良牧草造成不利,从而使杂草比例增加并进一步抑制牧场质量从而限制地区以畜牧业为主的经济发展.
2.The result showed that the amount of germinated soil seed banks in the four different degraded levels meadows (A-non-degraded Kobresia meadow; B-minor degraded meadow: C-medium degraded meadow; D-heavily degraded meadow) under the laboratory were A: 1194-3744 seeds/m2 and 2421.33 seeds/m2 in average;
结果表明,四种退化程度的高寒草甸(A-未退化嵩草草甸;B-轻度退化草甸;C-中度退化草甸;D-重度退化草甸)试验室条件下可萌发土壤种子库数量分别为,A:1194-3744粒/m2,平均为2421.33粒/m2;
3.Steppe diversity, however, is characterized by higher plant diversity in the ecotone, especially in the forest-meadow region. β diversity indices of plant communities reached peak values at the boundaries between the ecotone and the forest zone or the steppe zone, and between the forest-meadow region and the meadow-steppe region within the ecotone.
在森林-草原交错带β多样性指数较高，表现在β多样性指数在森林-草原交错带与森林带和草原带之间以及森林-草原交错带内森林草甸区和草甸草原区之间的边界不同程度地出现峰值。
4.The north slope on the east part of Qilian Mountains was separated into 6 vertical distribution zones: alpine cold desert meadow、alpine meadow、alpine bush meadow、mountain forest grassland、mountain grassland、and mountain desert grassland, there are also some areas of alternative distribution.
祁连山东部北坡根据气候、土壤、地貌等因素，分为6个垂直分布带：高山寒漠草甸带、高山草甸带、高山灌丛草甸带、山地森林草原带、山地草原带和山地荒漠草原带，有交替分布的地段。
5.The number of forest patches in forest-meadow regions is greater than that in the forest zone and in meadow-steppe regions.
在森林-草原交错带森林草甸区森林斑块的数量最多，其次为森林带，再次为森林-草原交错带草甸草原区，草原带没有森林斑块。
6.The early and middle Holocene epoch was in an environment of relative warm and humid veld to arid meadow vegetation; while the late epoch was in warm and humid veld to relative arid meadow vegetation environment.
全新世早-中期是一种比较温湿疏林草原—干早的草甸草原植被环境,晚期是一种温湿疏林草原—比较干旱的草甸草原植被环境.
7.Dynamics of inorganic nitrogen in soils are similar to the pools of nitrogen, cultivation marsh meadow, showing that the availability of nitrogen is the highest in the Mire-wetlands and the lowest in the cultivation.
无机氮(0～25cm)的动态与土壤全氮相似,其变化规律为耕地
8.the area percentages of temperate steppe type, temperate meadow steppe type, lowland meadow type, marsh type and temperate forage improved grassland are separately 85.11%, 1.23%, 12.19%, 1.19% and 0.28%.
温性草原类、温性草甸草原类、低地草甸类、沼泽类及改良草地面积占草地总面积的比例分别为85.11%、1.23%、12.19%、1.19%和0.28%；
9.The results showed that CO2 flux from alpine meadow is significantly positively correlated with 5 cm and 10 cm soil ground temperature and air temperature, the correlated coefficients between them are 0.917 30.852 6 and 0.910 4 respectively and almost have no correlation with 15 cm and 20 cm25 cm ground temperature . Therefore, 5 cm and 10 cm ground temperature and air temperature play key roles in the flux of CO2 from Alpine meadow.
结果表明,CO2排放通量日变化与气温、5cm和10cm地温呈明显的正相关关系,相关系数分别为0.9104、0.9173和0.8526,而与15、20和25cm地温相关性较小,说明在新疆高山草甸草原气温、5cm和10cm地温是影响草原群落CO2排放的关键性因子。
10.3. The grassland biomasses of meadow steppe, typical steppe, desert steppe and sand grassland have different correlations with three types of vegetation indices,EVI has the best correlation with meadow steppe;
3.锡林郭勒盟草甸草原区、典型草原区、荒漠草原区和沙地植被区实测草地牧草产量与三种不同植被指数的相关性存在一定差别,其中EVI与草甸草原区的相关性最好;
