宁夏黄土丘陵区苜蓿土壤水分的时空变异特征

• 作 者: 蔡进军 张源润 潘占兵 董立国 许浩 王月玲 季波 马璠 韩新生 李生宝
• 机 构: 宁夏农林科学院荒漠化治理研究所,
• 出 处: 水土保持研究
• 发表日期: 2016年01期
• 关键词: 紫花苜蓿 土壤体积含水量 时空变异

土壤水分是影响半干旱区植被生长和生态修复的限制性生态因子,开展土壤水分变化研究对脆弱生态系统的恢复和生产实践活动的指导都具有重要作用和实际意义。对半干旱黄土丘陵区苜蓿在时空尺度上土壤水分状况的变化规律进行了分析。结果显示:(1)不同类型苜蓿土壤体积含水量的年际变化规律大致相同,生长季变化大致可分为三个时期:土壤水分消耗期(3—5月)、土壤水分相对稳定期(6—7月)和土壤水分积累期(8—10月);(2)以不同深度土壤体积含水量的变异系数为标准,可将土壤水分的垂直分布划分为三个层次:0—20cm土壤水分速变层、20—80cm土壤水分活跃层和80—180cm土壤水分相对稳定层;(3)土壤体积含水量的坡向变化规律为西坡>北坡>南坡>东坡,不同年份规律大致相同,但有小范围的波动,坡位变化规律为坡上<坡中<坡下,不同年份间的变化基本一致。 Soil moisture is the limiting ecological factor that affects the vegetation growth and ecological restoration in semi-arid area. Carrying out the research on soil moisture change is of great significance and practical significance for the restoration of fragile ecosystems and the guidance of production practice. The changing rules of soil moisture on alfalfa in the semi-arid loess hilly region were analyzed. The results showed that: (1) The interannual variability of soil water content of different types of alfalfa was roughly the same. The change of growing season could be divided into three periods: soil water consumption period (March-May), soil moisture stable period - July) and soil water accumulation period (August-October). (2) Based on the variation coefficient of soil moisture content at different depths, the vertical distribution of soil moisture can be divided into three levels: 0-20cm soil moisture (3) The change trend of soil water content in the slope direction is west slope> north slope> south slope> east slope, and the laws of different years are roughly the same The same, but there is a small range of fluctuations, slope change rule for the slope