摘要
The daily soil water budgets in the red soil areas of central Jiangxi Province,southern China,were investigated with a large-scale weighing lysimeter and runoff plots. From 1998 to 2000,peanuts (Arachis hypogaea L.) and rape (Brassica napus L.) were planted in the lysimeter and in 1999,peanuts were planted in the runoff plots. The soil water budget components including rainfall,runoff,percolation and evapotranspiration were measured directly or calculated by Richards' equation and water balance equation. The results showed that most rainfall,including rainstorms,occurred from March to July,and induced the greatest soil water percolation during the year. The evapotranspiration was still large from July to September when rainfall was minimal. Thus,the lack of synchronization in soil water inputs and losses was disadvantageous to crops growing in this region. Among the soil water losses,percolation was the largest,followed by evapotranspiration,and then soil runoff. Runoff was very small on farmland with crops. It was significantly different from the uncultivated uplands where large-scale runoff was usually reported. The soil water storage fluctuated sinusoidally,with a large amplitude in the rainy season and a small amplitude in the dry season.
The daily soil water budgets in the red soil areas of central JiangxiProvince, southern China, were investigated with a large-scale weighing lysimeter and runoff plots.From 1998 to 2000, peanuts (Arachis hypogaea L.) and rape (Brassica napus L.) were planted in thelysimeter and in 1999, peanuts were planted in the runoff plots. The soil water budget componentsincluding rainfall, runoff, percolation and evapotranspiration were measured directly or calculatedby Richards' equation and water balanceequation. The results showed that most rainfall, includingrainstorms, occurred from March to July, and induced the greatest soil water percolation during theyear. The evapotranspiration was still large from July to September when rainfall was minimal.Thus,the lack of synchronization in soil water inputs and losses was disadvantageous to crops growing inthis region. Among the soil water losses, percolation was the largest, followed byevapotranspiration, and then soil runoff. Runoff was very smallon farmland with crops. It wassignificantly different from the uncultivated uplands where large-scale runoff was usually reported.The soil water storage fluctuated sinusoidally, with a large amplitude in the rainy season and asmall amplitude in the dry season.
基金
Project supported by the Knowledge Innovation Project of the Chinese Academy of Sciences (No. KZCX2-407).
关键词
红土
花生
油菜
土壤水分
red soil
runoff plot
water budget
weighing lysimeter