库姆塔格沙漠典型植物种群特征与自然环境要素的因子分析

通过对库姆塔格沙漠区的典型植物梭梭、胡杨、沙生柽柳的种群特征及其地理、土壤、水分三类要素的7种因子进行实地样方调查,并采用因子分析法,对影响三种群生长与分布的环境因子进行分析。结果表明:(1)土壤养分是区域三种群生存和发展的最主要影响因子,表明区域环境严酷、土壤贫瘠,对植物生长发育的限制作用明显。(2)海拔影响较小,并均与其它因子共同产生作用,表明地理因子对植物或植物种群的影响主要是通过对其它因子的作用而产生的间接影响。(3)水分对三种群的影响明显,且各不相同,水分与海拔高度变化具有一定的相关性,共同影响了三种群的分布和种群发展。(4)水分是影响梭梭和胡杨种群分布的主要因子,水分对沙生柽柳的影响反映了其生存环境的地下水位及其矿化度特征。研究认为,由于库姆塔格沙漠区域长期地质及气候环境变化形成的土壤基质在短期内难以得到改善,土壤养分匮乏的影响将长期存在,植物种群的保护与恢复存在较大难度,因此防治区域沙漠化发展、保护植物现有生境将是维持库姆塔格沙漠区域植物生长和种群发展的有效手段。

Factor Analysis of Natural Environmental Elements and Characteristics of Typical Populations in Kumtagh Desert

Haloxylon ammodendron,Tamarix taklamakanensis,Populus euphratica are the importance safety barriers to desertification and aeolian disaster combating,regional ecological balance maintenance,biological diversity conservation and the oasis safety in Kumtagh desert region.Seven factors of three elements,geography,soil and water of these three plant populations were chosen as indicators which have important influences.Using factor analysis,the environmental factors impacting on growth and distribution of three species were analyzed.The results showed that:(1)Soil nutrients were the most important factor of the survival and development of three regional species.It indicated that the regional harsh environment and poor soils had apparent limiting to plant growth and development.(2)The effect of altitude was less,and it had an effect together with other factors.The geographical factors on the impact of plant populations mainly arose from the indirect effects through the role of other factors.(3)Water affect significantly on three groups and varied,water and altitude changes had certain relevance,affected together on the distribution and population development of the three species.(4)Water was the main factor of distribution of P.euphratica and H.ammodendron species,and the impact on T.taklamakanensis reflected the underground water level and mineralization characteristics of their living environment.The soil which was formed during long term geology and regional climate change in Kumtagh desert was difficult to improve in the short term.And there had large difficulty on plant protect and restore for the effect of soil nutrient scarcity.Thus regional desertification combating and the existing habitat protecting will be more effective means to maintain regional plant growth and population development.