江西省鄱阳湖湖滨沙地蔓荆的固沙效益

Sand Fixation Benefits of Vitex trifolia L. in Bank Land of Poyanghu Lake in Jiangxi

摘要: 研究蔓荆植物在南方风沙化土地的阻沙、固沙作用,以及对土壤理化性状改良和小气候改善等方面的影响。结果表明:蔓荆植被覆盖率为10％～20％时,风蚀模数为2万4757t/（km²·a）,植被覆盖率达到40％时,年均风蚀模数只有2920t/（km²·a）;与裸沙地比较,5年生蔓荆地0～40cm土层的有机质、全N、全K、速效K分别增加了580％、100％、28.6％、67％;对于0～20cm土层,小于0.25mm的细沙粒增加98.7％;蔓荆地可降低地表最高温度10～12℃,增加空气湿度1.2％,有利于沙地植被的恢复。

Abstract: It was studied on the effect of Vitex trifolia L. to block and fix sand, to improve physical and chemical nature and micro-climate in the sand land of southern China. The results show that the annual sand land erosion modulus in average is 24757 t/(km²·a) under vegetative cover of 10%-20% and 2 920 t/(km²·a) under vegetative cover of 40%; compared to uncovered sandy land, on land covered by Vitex trifolia L. of 5-year growth soil organic matter is increased by 580%,total N by 100%, total K by 28.6%, rapidly available K by 67.0%, the amount of fine sand less than 0.25 mm is increased by 98.7%, the maximum temperature could be lowered by 10 - 12℃, and air humidity is increased by 1.2%, being propitious to the recovery of vegetation.