连古城自然保护区不同群落物种多样性研究

以期为干旱荒漠区物种多样性的保护和利用方面提供理论依据，以民勤连古城自然保护区荒漠植被典型群落为研究对象，应用物种多样性指数、土壤水分变化动态、降雨量等指标因子变化动态趋势对群落演替过程中进行了研究。结果表明：（1）根据群落土壤水分条件变化趋势从高到低依次为：典型群落Ⅲ＞典型群落Ⅱ＞典型群落Ⅴ＞典型群落Ⅳ＞典型群落Ⅰ；（2）不同群落物种多样性指数由大到小排列顺序为：典型群落Ⅴ＞典型群落Ⅱ＞典型群落Ⅲ＞典型群落Ⅰ＞典型群落Ⅳ，整体表现为群落多样性指数均偏低，生态优势度较高；（3）2014年的降雨量高于2013年，降雨量分别为142.9、108.7 mm，2014年除12月外，每月均有不同程度的降雨。可得出结论：物种多样性指数受降水的影响，相应出现增加或减少趋势，但降水对物种多样性的影响效应具有一定的滞后性，要经过一段时间才能充分表现出来。在群落演替进化过程中种群将保持合适大小，群落表现出最大的适应能力，保持种群避免灭绝。

Diversity of Different Communities and Species in Liangucheng Nature Reserve Area

In order to provide theoretical foundation for the protection and utilization of species diversity in arid desert region, the typical desert vegetation communities in Minqin Liangucheng Natural Reserve Area was used as the study object, community succession process was studied through the indexes of species diversity, soil water content and precipitation. The results showed that: (1) soil water content in different communities followed the order of typical community Ⅲ ＞ Ⅱ ＞ Ⅴ＞ Ⅳ ＞ Ⅰ; (2) species diversity index followed the order of typical community Ⅴ ＞ Ⅱ ＞ Ⅲ ＞ Ⅰ ＞ Ⅳ, the species diversity indices was low, but ecological dominance was high; (3) the amount of precipitation in 2014 was higher than that in 2013, which was 142.9 and 108.7 mm respectively, there were different levels of rain events in each month of 2014 except December. Species diversity index showed increase or decrease trend affected by precipitation, but the influencing effect had certain hysteresis, its full performance showed after a period of time. The community could keep a suitable size during the succession process, and show the greatest adaptive capacity to avoid extinction.