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2009年6月到9月,每月中旬在民勤绿洲边缘不同林龄(2 a,5 a,10 a,20 a,30 a)的人工梭梭林内测试不同深度(20 cm,30 cm,50 cm,100 cm,150 cm和200 cm)的土壤含水量变化情况。分析结果表明,不同林龄的梭梭林内土壤含水量与时间和深度有关。土壤表层含水量主要受自然降雨控制,8月底发生比较大的自然降雨后,9月不同林龄梭梭林内20 cm和30 cm的含水量显著高于其他3个月。土壤50 cm以下的含水量比较稳定,当降雨少,土壤表层含水量低时,可以作为梭梭利用的水分来源。在7月和8月,5 a梭梭林内土壤含水量最低,表明梭梭对土壤水分的消耗最多,栽植密度过大,因此,需要间伐减少植株数量才能维持其稳定性。
From June to September in 2009, mid-month, different depths (20 cm, 30 cm, 20 cm, 30 cm, 50 cm, 100 cm, 150 cm and 200 cm). The results showed that the soil moisture content of Haloxylon ammodendron forests varied with time and depth. Soil surface water content was mainly controlled by natural rainfall. After relatively large natural rainfall occurred at the end of August, the moisture content of 20 cm and 30 cm in Haloxylon ammodendron forests of September was significantly higher than that of the other three months. Soil moisture below 50 cm is relatively stable, and can be used as a source of water for Haloxylon ammodendron when rainfall is low and soil moisture content is low. In July and August, the soil water content of Haloxylon ammodendron was the lowest in 5 years, indicating that Haloxylon ammodendron had the highest soil water consumption and planting density. Therefore, it was necessary to reduce the number of plants to maintain its stability.