Characteristics Of Soil Nutrients And Enzyme Activities Of Ancient Tea Garden In Jingmai, Lancang, Yunnan

Camellia sinensis var. assamica is the principal raw material of Pu-erh Tea, and there's a long history of tea planting in Xishuangbanna, Simao, Lincang, etc of Yunnan Province. The largest Ancient Tea Gardens (ATGs) with oldest tea trees are distributed in these areas. ATGs are very special ecosystems with high biodiversity and plenty of wild plant resources. Moreover, ATGs have special self-sustaining capability of soil fertility maintenance and self-protection from pests. Without artificial fertilizers and pesticides, Pu-erh tea produced here could keep its excellent quality. ATG in Jingmai, Langcang County is a typical example of cultivated ATGs. In this research, ATG soil in Jingmai and its neighboring conventional tea garden (CTG) and forest soils were sampled and assayed for soil nutrients and soil enzyme activities. Another experiment was designed to test effects of sample storage under different conditions on soil enzyme activities. The main conclusions were listed as follow:1) Soil moisture showed no marked difference between the top layer (0~20 cm) and deeper one (20~40 cm), while there's significant difference among different land uses, with an order of CTG< ATG< Forest.2) All the soils sampled were acid, with a pH of 3.80~3.91 in wet season and 4.00~4.24 in dry season. Soil pH was lower in tea garden, and the acidification was also more serious under older tee plants.3) Content of OM, N, P and soil enzyme activities were higher in the top soil, while Mg, Al and K showed no such marked vertical difference. The content of OM was much higher than average tea gardens in other areas. The content of N and OM had an order of CTG< ATG