茶园——土壤系统的物质循环对土壤酸化的影响

基于植茶后土壤酸度逐渐增高,盐基含量降低,铝饱和度增加,土壤呈现酸化现象。本文通过茶园—土壤系统中铝、锰、钙、镁等矿质元素循环,探讨了茶园土壤酸化的原因。在江苏省金坛县茅麓茶场的黄棕壤上,对不同植茶年限(9龄、29龄、80龄)茶园的茶树茎流、透冠水和土壤渗漏水的化学成分进行了分析研究。茶树是富集铝和锰的植物,茶树茎流与透冠水相比,具有含铝多、含盐基少、pH 值较低的特点。茶园土壤酸化受茶树群体分布的影响而存在着不均一性,植茶初期离茶树根颈近的土壤率先酸化,随着植茶年限的延长和茶树群体覆盖度的增加,茶树落叶

Effect of Biogeochemical Cycle in Tea Garden on the Soil Acidification

The tea stemflow,throughfall and the soil percolating water wereinvestigated in tea gardens(located on yellow-brown earth)with teaplants of 9,29 and 80 years old on Maolu Tea Plantation,JintanCounty,Jiangsu Province.Results indicated that,comparing with thethroughfall,the stemflow contained more aluminium and fewer basicions,and had a lower pH value.In the initial stage of plantation,the leading acidification occurred in the soil around the tea col-lets.The litter played a dominant role in the soil acidification asthe time passed,resulting in lower pH values in the soil far fromthe collets.Therefore,the biogeochemical cycle of substances led tothe acidification of the whole pedon in the tea garden ecosystem.Inthe course of the soil acidification,large amounts of calcium andmagnesium were leached,and the leachings of aluminium and manganese,especially of manganese,increased with the increasing of the degreeof the soil acidification.