极端干旱沙漠中无沙埋干扰时几种固沙植物栽植试验研究

沙埋干扰是沙漠地区乡土植物生存繁殖的必要条件。在塔克拉玛干沙漠腹地,无沙埋干扰地段大多是高矿化度地下水埋深较浅的地段,这些地段盐渍化较重。7a定点观测和试验表明,塔里木沙漠公路沿线丘间地栽植固沙植物逐渐死亡的主要因素不是沙层水分和沙层盐分,而是高矿化度地下水埋深太浅(0.8～1．0m),即这类地段植物死亡的原因主要是由于植物长期吸收高矿化度地下水使得体内盐分积聚过多无法调节而造成的。因此,在干旱区高矿化度地下水埋深太浅的地段,无沙埋干扰时建立固沙植被应谨慎。

Cultivation Experiment of A Few Sand-binding Plants without Sand Bury in the Extremely Arid Desert

It is generally considered that sand bury is a necessary condition to the growth and the reproduction of native plant in sandy desert. But, if sand\|binding plantation is constructed in the sites without sand bury, what results may be taken? A cultivation experiment has been conducted to find the possibility of establishing sand\|binding plantation in the shallow groundwater sites in the hinterland of Taklimakan Desert, where are often not suffered with sand bury and the salinity in sand layers is great. Observation in this site for seven years showed that the main factors limiting the growth of sand\|fixation plants are not soil water content and soil salt content,but the shallow groundwater table (range from 0.8 m to 1.0 m) with high salinity along Tarim Desert Highway. In the other word,the cultivated plants always absorbed the groundwater with high salinity and could not regulate the accumulated salts of their body; As result, the plants died out. So it must be cautious to establish sand\|binding plantation in the regions with shallow groundwater table and high soil salinity as well as not suffered with sand bury.