生态种的

We choose the arid land of northwestern China as our study area because of its extensive area, specific geographical location, dry climate, varied topography, vulnerable ecosystems and long-term human disturbance, as well as the existence of current conflicts between economic development and environmental protection. Based on the literature, we choose ten desert species with clear and relatively accurate geographical distribution ranges to model their distributions:Anabasis brevifolia, Atraphaxis frutescens, Calligonum mon-golicum, Ephedra przewalskii, Gymnocarpos przewalskii, Haloxylon ammodendron, Haloxylon persicum, Ka-lidium cuspidatum, Salsola laricifolia, and Sympegma regelii.

：选择面积广阔、地理位置特殊、气候干旱、地形地貌多样、生态系统脆弱以及人类活动长期干扰，而且目前面临着西部大开发和环境保护双重矛盾的西北干旱区作为研究区域，通过收集西北干旱区多种优势种和常见种的地理分布资料，选取10种分布范围相对明确、资料相对齐备的荒漠植物种：短叶假木贼、木蓼(A- traphaxis frutescens)、沙拐枣、膜果麻黄、裸果木、梭梭柴、白梭梭、尖叶盐爪爪、松叶猪毛菜(Salsola lar- icifolia)和合头草，定量分析其地理分布与气候因子的关系，并据此估测其潜在中心分布区和潜在最大分布范围，与实际分布范围进行比较。

The bark beetle species on Pinus armandi and their niches were studied in the middle areas of Qinling Mountains. The results showed that 19 species of bark beetles infecting and damaging Pinus armandi in pine ecosystem of Qinling Mountains were found, but only 11 species of them could be competitive and coexistent one another.

通过对秦岭林区海拔1600-2200m的中山地带华山松小蠹虫种类和生态位的研究，结果表明：在秦岭林区入侵危害寄主华山松的小蠹虫有19种，其中能构成竞争和共存的小蠹虫主要有11种。

Analyses of niche breadths and overlaps of several plant species in three Kobresia communities of an alpine meadow .

三种蒿草群落中若干植物种的生态位宽度与重叠分析。

Pattern of use for these resources was analyzed from three vegetation types by examining species-specific niche breadths, overlaps and partitions of resource utilization as well as population sizes.

对于这些资源利用的格局是通过对存在于三种类型植被中蝗虫种的生态位宽度、资源利用的分化和重叠以及每种蝗虫的种群大小来分析的。

A taxonomic species considered in terms of its ecological characteristics and usually including several interbreeding ecotypes.

生态种按生态学特征划分的分类种，常包括一些杂交生态型

Also, during this process, the water content in vegetation increases and keeps stable gradually, and the water environment in ecosystem will become suavely.

摘 要：本文以南亚热带常绿阔叶林为基本，同时探讨了热带南亚热带森林演替系列中8种生态系统类型的水分结构，发现植被水分结构的恢复与土壤水分结构的恢复是不同步的，50a以上没有受扰动的土壤，其土壤水分结构在时空上才趋于稳定；植被水分结构的时空稳定性基本上与生态系统的演替状况一致；为满足植被蒸腾的需要，植被中水分的月更新次数随着群落向顶极系统的演替而逐渐减少。

The achievement of this project can be briefly summed up as following:(1)the carbon contributing to karst processes mainly comes from ecological system itself under the condition of existence of vegetation and soil covers;(2)results indicates that the depositing processes of rainfall to CO2 is an important "sink" to global carbon cycle;(3)owing to the differences of vegetation and surface covering, the adjusting effect of ecosystem to environmental humidity, temperature and CO2 concentration near surface air which indicates different benefit of preventing water and soil from lose is marked;(4)the preponderant species of vegetation in the karst ecosystems which have different kinds of carbonate rocks are obviously variant, and this situation results to the clearly differences of the micro － habitat , structure of surface cover and water holding capacity;(5) the relevant study showed that the carpophagous animals and birds make a important role in the spreading of vegetation seeds. The designed experience for the study of seed reservoir was not able to obtain a satisfactory result.

主要研究成果包括：通过对表层系统碳库的研究，认为在有土壤和植被覆盖时，岩溶作用过程中的碳主要来自生态系统本身而不是母岩；降雨对大气碳具有重要&沉淀&作用，是碳的一个重要汇；不同植被类型表层岩溶系统对系统水份、空气湿度、气温、土温和近地表 CO2浓度等具有明显调节作用，具有不同的水土保持效益；不同母岩的岩溶生态系统的植被优势种、属差异明显，由此形成的小生境、地被物及其持水性差异巨大；对典型岩溶表层系统种子库的试验研究没有取得满意结果，但食果动物、鸟类对种子传播起到一定作用。

We analyzed the relations of plant ecological type groups and community biomass and environment changes in the grassland communities of Leymus chinensis as edificator along Northeast China Transect.

初步分析了中国东北样带以羊草为建群种或共建种的草原群落植物水分生态类型功能群生物量及其与群落初级生产力和环境变化的关系。

On the basis of examination of more than 2000 specimens from 15 herbaria worldwide, the characters features of species,phonological phase,ecoloigical habit and the relation to close species were analyzed, recorded and described, the disputed species were compared, measured and counted in detail, the quantitative analysis to different characters was done through dot-map, the variation pattern of major morphology characters was analyzed and their significance for a better delimitation of the species was evaluated.

查阅或借阅国内外17个标本馆近2000份标本，描述了每个种的性状特征、物候期、生态习性及其与近缘种的关系，确定性状的极性，对有争议种的形态性状进行详细的测量和比较，用散点图对个别性状作定量研究，分析了主要外部形态学性状的变异式样、变异幅度及其对划定物种范围的价值。

These results can shed lights on revealing the mechanisms of plant's adaptation to xeric conditions, as well as the effects of anthropogenic disturbances on the local extinction of native species, and/or invasion of shrubs.

我们的研究结果从植物种、功能群和群落三个层次进一步揭示了植物对干旱生境的适应机制，并初步阐明了人类干扰特别是过度放牧对草原群落建群种和优势种的生态替代或/和灌丛入侵的影响。

In the United States, chronic alcoholism and hepatitis C are the most common ones.

在美国，慢性酒精中毒，肝炎是最常见的。

If you have any questions, you can contact me anytime.

如果有任何问题，你可以随时联系我。