民勤荒漠区白刺群落和沙蒿群落的自然更新能力研究

民勤是我国典型的荒漠化地区，白刺群落和沙蒿群落是民勤荒漠区两个最重要的天然植被群落，研究其天然更新能力对于荒漠区植被恢复与保护意义重大。笔者通过设固定样方，定位观测，研究了白刺群落的白刺和沙蒿群落中的沙蒿的自然能力，结果表明：1）白刺群落和沙蒿群落在沙丘和丘间滩地上均可产生更新苗，沙丘更适合白刺和沙蒿的更新；2）白刺群落中白剌小苗密度和沙蒿群落中沙蒿小苗密度差异为极显著，沙丘和丘间滩地之间更新密度的差异以及不同年份之间更新密度的差异均为不显著；3）不论是白刺群落中的白刺小苗密度还是沙蒿群落中的沙蒿小苗密度都与当年降水量存在一定的正相关关系，尤其是与当年5月份的降水量和全年降水量关系密切。

Research on Natural Reproduction Ability of Nitariatangutorum Community and Artemisiaarenaria Community in Minqin desert area

The Minqin county is model desertification area. Nitariatangutorum community and Artemisiaarenaria community are the two most important natural vegetation communities in Minqin desert area. The significance is significant on studies with natural regeneration ability of vegetation for the vegetation restores and protects. The author has studied natural regeneration ability of Nitariatangutorum community and Artemisiaarenaria community by localization observation. The result show: 1) The Nitariatangutorum community and Artemisiaarenaria community have ability to produce the sprout in sand dune and bottomland. 2) The difference is very significant between the seedling density of Nitariatangutorum in the Nitariatangutorum community and the seedling density of Artemisiaarenaria in Artemisiaarenaria community. The difference of seedling density is not significant between sand dune and bottomland and Between different year. 3) There are positive correlation between density and precipitation about Nitariatangutorum in Nitariatangutorum community and about seedling Artemisiaarenaria in Artemisiaarenaria community. Especially positive correlation is more remarkable between seedling density and same year May's precipitation and annual precipitation.