3种典型生物措施对亚热带红壤丘陵茶园季节性干旱的防御效果

Defensive Effects of Three Representative Biological Measures on Seasonal Drought in Tea Plantation in Subtropical Red Soil Hilly Region

在采集湖南省长沙县1960～2001年气象资料的基础上．探讨了我国亚热带红壤丘陵茶园夏季高温干旱和秋季持续干旱的发生规律，并以常规管理茶园为对照，通过2001～2004年连续4年大田对比试验，分析了杉树高层间作、白三叶草低层间种和稻草覆盖3种典型生物措施对茶园季节性干旱的防御效果，结果发现，3种生物措施明显减少了茶园全年0～20cm土层土壤含水量≤15％，≤12％，≤10％的出现频率，在夏季高温干旱和秋季持续干旱时期均提高了茶园土壤含水量，有效地延缓和缩短了干旱时间，缓解了旱情，显著增加了夏秋茶产量，改善了夏秋茶品质。

On the basis of the collection of weather data from 1960 to 2001 of Changsna county, Hunan province, the law of drought with high temperature in summer and continuous drought in autumn was discussed in subtropical red soil hilly region in China. Defensive effects of the three representative biological measures （i. e. upper-intercropping fir, lower-intercropping white clover and straw mulching） on seasonal droughty in tea plantation were studied through continual 4 years＇ large-field contrast experiments from 2001 to 2004 and taken general tea plantation as control. It was found that the three measures evidently decreased the frequency of whole year soil water content ≤15%, ≤12% and ≤10% in 0-20cm in tea plantation and increased soil water content during the period of high temperature drought in summer and continuous drought in autumn. Moreover, they effectively delayed and shortened the drought, and then alleviated the seriousness of drought. Furthermore, to summer and autumn tea, they improved the quality and remarkably increased the yield.