Soil Nutrient Status at Zhayun,Qiongzhong County of Hainan Province
A study on soil nutrient status at Zhayun,Qiongzhong County of Hainan Province was conducted and 276 soil samples were collected to determine pH,organic matter,nitrogen,phosphorus,potassium,calcium,magnesium,zinc and boron contents in November,2007.The results showed that:(1)Of the 276 collected soil samples,235 ranged from 4.6 to 5.5 and 21 from 5.5 to 6.5,apparently,the soils had strong acidity;(2)Soil organic matter ranged from 0.25 to 34.0 g/kg with a mean of 17.0 g/kg,which was ranked in the middle level;(3)Soil total nitrogen ranged from 0.33 to 2.07 g/kg and available nitorgen ranged from 60～150 mg/kg;(4)Soil phosphorus contents,whatever in total form or available form were extremely low ranged from 0.171 to 0.384 g/kg with a mean of 0.231 g/kg and from 0.3 to 54.2 mg/kg with a mean of 4.4 mg/kg for total P and available P,respectively;(5)Both total potassium and available potassium were extremely deficient ranged from 0.58 to 19.08 g/kg with a mean of 4.42 g/kg and from 13.9 to 362.5 mg/kg with a mean of 65.5 mg/kg for total K and available K,respectively;(6)Soil exchangeable calcium were relatively high with a mean of 740.4 mg/kg while soil exchangeable magnesium were low with a mean of 68.4 mg/kg;(7)As micronutrients,available zinc in the soil was high with a mean of 1.85 mg/kg and soil boron was extremely low with a mean value of 0.128 mg/kg.