稻草覆盖对云南高原魔芋地温时空变化的影响

Effects of Straw Mulching on Temporal Spatial Variation of Soil Temperature of Konjac Plantation in Yunnan Highland Region

连续三年研究稻草覆盖对云南高原山地栽培‘花魔芋’地温时空变化的影响。结果表明:地温具有明显的时空变化特征,与‘花魔芋’的年生长周期各发育阶段的最适温度相吻合。稻草覆盖改变土壤热量交换层(地表层)的性质,具有延缓地温上升和下降的双向动态调控作用,调控幅度随气温升高而增大,随气温下降而加强;增强了同一土层温度的稳定性,其调控幅度随着土壤深度增加而降低,不同观察时间表现出13:00>19:00>7:00的规律。

The effects of straw mulching on temporal spatial variation of soil temperature of konjac plantation in Yunnan highland region were studied for three years continuously. The results showed that the soil temperature presented a significant variation, which were coincident with the optimum temperatures of konjac at different stage of annual growth cycle. Straw mulching altered the nature of soil thermal exchanging layer （soil surface）, meanwhile it had a double-side effect on slowing down the raise and the decline of soil temperature, with the regulation breadth increasing when air temperature increased or decreased. As a result, the temperature stability in same soil layer was enhanced. However, the regulation breadth decreased while soil depth increasing. Observation time showed a rule as： 13：00〉19：00〉7：00.