Study On Relationship Between Soil Nutrients And The Corresponding Components In Tea Of Shaanxi Province

Shaanxi has a long history of producing tea, and the main producing areas of which are Hanzhong city, Ankang city and Shangluo city. Soil is the foundation for the growth of tea, supplying the essential nutrients, and playing an important role in the high yield and quality of tea. By the methods of field sampling survey, laboratory analysis and computer technique, the content of tea in 99 tea gardens, 495 sampling sites of 3 cities and 8 counties of Southern Shaanxi and tea related composition were investigated, and soil nutrients in tea gardens and tea related composition of distribution characteristics were definited, then it provide the basis for correctly judging the condition of soil nutrient supply and tea trees'application to soil available nutrients.In present research, soil pH value, organic substance, available N, available P, available K, microelements Zn and Se as well as the contents of N, P, K, Zn, Se in tea were tested as indexes. The following results were obtained:(1) Soil of Shaanxi tea gardens generally has low content of organic substance, which is about 0.96~43.34 g/kg, falls short of the requirement of a high quantity and quality tea garden; pH value ranges during 4.08~6.93, can satisfy tea growing for the basic need of soil pH condition.(2) Soil comprehensively has higher level of available N, ranges from 28.35~277.14 mg/kg, among which, Mian county has the highest averaged content, which is about 168.98 g/kg; Available P content was at extremely low level, ranges from 0.35~10.89 g/kg, with the highest averaged content of 10.34 g/kg in Shangnan county; Available K content retained in medium, from 0.35 to 10.89 g/kg, thereinto, Ziyang county has the highest averaged content of 215.53 g/kg.(3) The Zn content of Soil ranges from 0.379 mg/kg to 1.585 mg/kg which is the highest with 0.983 mg/kg averaged content in Pingli county, while the Se content of soil ranges from 0.216 mg/kg to 43.013 mg/kg, with the highest averaged content of 3.986 mg/kg in Xixiang county.(4) The N content of tea ranges during 36.14 g/kg and 44.72 g/kg, averagely 40.04 g/kg, among the middle level. Thereinto, the highest is in Mianxian county tea garden, about 44.72 g/kg; P content ranges from 1.273 g/kg to 1.430 g/kg, the average of the collectivity is 1.36 g/kg, at a extremely low level; the K content of tea ranges from 10.983 g/kg to 12.585 g/kg, the average content is 11.89 g/kg, so that belongs to relatively low level.(5) The Zn content of tea ranges from 39.16 mg/kg to 51.46 mg/kg and Mianxian county has the highest content; Se content of tea varies from 0.818 mg/kg to 3.537 mg/kg with the highest value in Xixiang county.(6) pH value shows significantly negative correlation or extremely significant, negative correlation with organic substance, available N and available K while organic substance has significant positive correlation or extremely significant, positive correlation with available N and available K.(7) Organic substance shows not very significant positive correlation with Se content, but appears negative correlation with Zn; pH value has positive correlation with Zn and Se content though not significantly.(8)The applying proportion of Zn relative to soil is 31.63%～39.13%, the applying proportion of Zn in Shangnan county is the lowest; The applying proportion of Se relative to soil is about 25.80%～62.82%, among which the proportion is the highest in Nanzheng county.