塔里木河下游地下水埋深与建群植物盖度之间的耦合模型研究

Research on the coupling model between groundwater level and the coverage of dominant species in the lower reaches of Tarim River

文中采用对数正态分布模型,通过对塔里木河下游地区进行野外实地监测,建立了研究区内建群植物-胡杨与柽柳盖度和地下水埋深之间的关系模型,并依据输水次数和地下水埋深的变化对研究区内建群物种的潜在盖度进行了模拟。结果表明:1)胡杨最适地下水位与平均地下水位分别为2.43m和4.58m,而柽柳的为2.31m和3.53m;2)模型所计算的结果与黑河流域额济纳旗地区相一致,准确度较高,具有一定的实用性;3)在研究区内,胡杨和柽柳潜在的盖度分别为16.98%和17.24%,与实测值之间没有显著性的差异,造成这些微小差异的原因主要是人类活动和气候变化的影响。

In this research,we did some field survey for Populus euphratica and Tamarix chinensis in the lower reaches of Tarim river. We established a relational model between the coverage of two species and groundwater level according to the Lognormal distribution model; then,simulated the potential coverage used for the frequency of water conveyance and the changes of groundwater level. The results were as follows： 1） The optimum groundwater level and the average groundwater level of Populus euphratica is 2. 43 m and 4. 58 m respectively,what to Tamarix chinensis is 2. 31 m and 3. 53 m. 2） The results,calculated by model,is corresponded with that at Ejin Banner in Heihe river basin. Therefore,this model has a high degree of accuracy,and some definite practicability. 3） In the study area,the potential coverages of Populus euphratica and Tamarix chinensis,may mainly affected by human activity and climate changes,are of 16. 98% and 17. 24% respectively,has some differences to survey results.