北京保护性耕作条件下土壤水分动态变化研究

• 作 者: 金复鑫 彭文英 张科利 王龙
• 机 构: 北京师范大学地理学与遥感科学院,首都经济贸易大学城市学院土地资源与房地产管理系,
• 出 处: 土壤通报
• 发表日期: 2009年01期
• 关键词: 冬小麦 保护性耕作 传统耕作 免耕覆盖 土壤水分 耕作条件 土壤含水量 春玉米 土壤侵蚀 播种期

保护性耕作能有效地控制土壤侵蚀,抑制地表起沙,防治土壤退化。在北京保护性耕作措施的实施背景下,针对土壤水分这一农业生产的重要限制性因子,通过大田试验研究了不同耕作措施下土壤水分的时空动态变化。结果表明:免耕覆盖能很好地保持土壤水分,免耕覆盖冬小麦和玉米土壤水分比传统耕作高13.7%、10.9%;免耕覆盖冬小麦在土壤表层的保水效果最为显著,高于免耕覆盖玉米,而在根层下部免耕覆盖玉米的保水效果高于冬小麦;耕作措施对土壤水分的影响具有季节变化,免耕覆盖冬小麦在播种期和收割期具有很好的保水作用,免耕覆盖玉米的保水作用主要表现在玉米拔苗成熟期;免耕覆盖在干旱季节的保水效果显著,秸秆覆盖的好坏也直接影响土壤水分。其研究可为北京免耕实施的推广提供理论依据,也为土壤学和作物学等提供基础资料。

Conservation tillage can effectively control soil erosion, inhibit surface sediment and prevent soil degradation. Against the background of the implementation of conservation tillage measures in Beijing, the spatial and temporal dynamic changes of soil moisture under different tillage practices were studied through field experiments on the important limiting factors of soil moisture, an agricultural production. The results showed that no-tillage cover could maintain soil moisture well, and the moisture of tillage-covered winter wheat and maize was 13.7% and 10.9% higher than that of conventional tillage. The water retention effect of no-tillage-covered winter wheat on soil surface was the highest, Maize, while the tillage-covered maize in lower root layer had higher water holding effect than winter wheat. The tillage measures had a seasonal change on the soil moisture. Tillage-covered winter wheat had good water retention at sowing and harvesting stages, The water retention of maize seedling was mainly manifested in the mature stage of maize tillage. The no-tillage cover had a significant water holding effect in the dry season, and the straw mulching also had a direct impact on soil moisture. Its research can provide a theoretical basis for the promotion of no-till implementation in Beijing and provide basic information for soil science and crop science.