双行凹型垄及覆盖措施对黔北烟区耕层土壤水分的影响

Effects of Bi-row Concave Ridge and Film-mulching on Soil Moisture of Tillage Layer in North Guizhou Tobacco Area

摘要: 在黔北烟区平坦黄壤旱地和15°、25°黄壤旱坡地上，以单行垄地膜覆盖、团棵揭膜为对照，研究了双行凹型垄及其覆盖技术对10 cm和20 cm土层土壤水分的影响。结果表明：一般情况下，浅表层（垄表下10 cm）的含水率高于较深层次（垄表下20 cm），灌溉可以打破这一规律；双行凹型垄较单行垄能促进自然降水向垄体内补充水分，增加垄内土壤的含水率或降低土壤水势；在双行凹型垄上全生育期覆盖地膜，可抑制浅表层土壤水分的无效散失，保水效果明显；在双行凹型垄全生育期覆盖地膜的基础上，遇旱灌溉能提高耕层土壤含水率或降低土壤水势，进一步优化了土壤水分环境。

Abstract: The experiment was carried out both in flat and sloping tobacco fields of north Guizhou Province to study the effects of of bi-row concave ridge and film-mulching on soil moisture at 10 and 20 cm tillage layers. The results showed that the soil moisture content was higher in 10 cm than in 10-20 cm under ridge surface without irrigation. The Bi-row concave ridge increased the soil moisture content and decreased the soil moisture potential in rows. In the whole period of tobacco growth, film mulching on the bi-row concave ridge reduced evapotranspiration from surface soil. These effects were further strengthened with irrigation treatment when drought occurred.