民勤荒漠区4种植物的防风固沙功能对比分析

Comparison on functions of wind break and sand fixation four plant species in Minqin desert

梭梭(Haloxylon ammodendron)、沙蒿(Artemisia desertorum)、白刺(Nitraria tangutorum)和膜果麻黄(Ephedra przewalskii)是民勤荒漠区主要的牧草,分布面积较大。为了研究荒漠区牧草植物的防风固沙功能,在牧草利用的同时兼顾防风固沙功能。本研究用民勤荒漠区4种主要防风固沙植物样方调查资料,通过计算单株植物的纵断面积和单位面积上的纵断面积,以及单株植物的固沙沙堆体积和单位面积上的固沙沙堆体积,对4种主要植物群落的防风功能和固沙功能进行了对比分析。结果表明,单株(丛)的防风功能的排序为白刺>梭梭>沙蒿和膜果麻黄,单株(丛)的固沙功能白刺>膜果麻黄,单位面积上防风功能的排序为沙蒿>梭梭>白刺>膜果麻黄,单位面积上的固沙功能白刺>膜果麻黄;单位面积上防风固沙功能的排序为白刺>沙蒿>梭梭>膜果麻黄。如果只选择防风,则应选用沙蒿;如果侧重点是固沙,则应选用白刺;如果二者兼顾,则应选用白刺和沙蒿。

Haloaylon ammodendron,Artemisia desertorum,Nitraria tangutorum and Ephedra przewalskii are widely distributed in Minqin desert,which are the major forages in this area.In the present study,we examined the functions of wind prevention and sand-fixing of these plants.We calculated the vertical section per crown and the vertical section per unit area.We also calculated the volume of sand fixed by each crown and the volume of sand fixed per unit area.Then the functions of wind prevention and sand fixing of these plants were compared.The results showed that the function of wind prevention of a single crown was decreased in the following order： N.tangutorum〉H.ammodendron〉A.desertorum〉E.przewalskii.The function of sand-fixing of a single crown was N.tangutorum〉E.przewalskii.The functions of wind prevention and sand-fixing per unit area were decreased in the following order： N.tangutorum〉A.desertorum〉H.ammodendron〉E.przewalskii.If wind prevention is the main purpose,A.arenaria should be chosen.If sand-fixing is focused,N.tangutorum should be chosen.If both of these functions are considered,N.tangutorum and A.desertorum will be a good choice.