Abstract: This paper investigated the effects of four years intercropping white clover in a one-year old tea plantation on soil environment,and tea yield and quality in subtropical hilly region.The results showed that intercropping white clover decreased soil bulk density,increased soil porosity and the contents of soil organic matter,total nitrogen,available nitrogen and available potassium,and partly consumed soil organic phosphorous.It increased the moisture content in key soil layer (0～20 cm) during key time (April-June),and also,postponed and shortened the period of high temperature in summer and the continual drought in autumn.Intercropping showed duplex effects of raising and keeping temperature at cold time while lowering temperature during hot season,making the temperature of same soil layer more stable.Intercropping also postponed the coming of high and low temperature,shortened the duration of extreme high temperature,lightened the effects of high temperature on tea tree growth,and thus,boosted the growth of tea tree,and improved the tea yield and quality.Compared to single-cropping,intercropping decreased the ratio of polyphenol to amino acid in spring and autumn tea by 17.10% and 30.90%,respectively, and increased the tea yield by 32.65%.

Key words: Medicago sativa, Astragalus adsurgens, Seedling growth, Soil moisture, Water consumption