海南岛中部山区土壤养分状况研究——以琼中黎族苗族自治县什运乡为例

Soil Nutrient Status in the Central Hainan Island--A Case Study in Zhayun Township,Li and Miao Autonomous County,Hainan Province

我们在海南中部山区琼中黎族苗族自治县什运乡采集了各类土壤样品276个,系统测定了pH、氮、磷、钾、钙、镁、锌、硼等含量,应用第二次土壤普查土壤养分分级标准和全国农业技术推广服务中心微量元素含量分析要求,对其进行养分状况评价。结果表明:①什运乡81.5%的土壤pH分布在4.6~5.5之间,属于强酸性土壤;②91.3%的土壤有机质含量分布在10.1g/kg^30.0g/kg之间,处于中等水平;③79.7%的土壤全氮含量分布在0.076%~0.150%之间,处于中等水平,而87.7%的土壤碱解氮分布在60mg/kg^150mg/kg之间,处于中等偏上水平;④92.4%的土壤全磷含量分布在0.2g/kg^0.4g/kg之间,处于低至极低水平,而76.1%的土壤速效磷含量分布在3mg/kg以下,处于极低水平;⑤95.6%的土壤全钾含量分布在5.0g/kg^10.0g/kg之间,处于低至极低水平,而81.9%的土壤速效钾含量分布在30mg/kg^100mg/kg之间,处于中低至极低水平;⑥各等级的土壤交换性钙的分布较为均匀,高、中、低的频率分别为38.7%、20.3%、41.0%;⑦76.1%的土壤交换性镁含量分布在50mg/kg^100mg/kg之间,处于低至极低水平;⑧99.7%的土壤有效锌的含量多在0.51μg/g^3.00μg/g之间,处于中等至极高水平;⑨所有土壤有效硼的含量分布在0.20mg/kg^0.50mg/kg之间,处于低与极低水平。

Soil nutrient status in Zhayun township,Qiongzhong Li and Miao Autonomous County,Hainan Province was studied by analyzing 276 soil samples collected from both cultivated and uncultivated lands in 2007.The results showed that:①Of 276 soil samples,235 had pHs ranging from 4.6 to 5.5 and 21 from 5.5 to 6.5,showing strong acidity.②Soil organicmatter ranged from 0.25 to 34.0 g/kg with a mean of 17.0 g kg-1,falling in medium levels.③Soil total nitrogen was 0.33 g kg-1 to 2.07 g kg-1,lineally correlated with soil organicmatter.④Both soil total phosphorus and available phosphorus were extremely low,ranging from 0.171 to 0.384 g/kg and averaging 0.231 g/kg for the total P,and from 0.3 mg/kg to 54.2 mg/kg and averaging 4.4 mg/kg for available P.⑤Total soil potassium and available potassium were also extremely deficient,ranging from 0.58 g/kg to 19.08 g/kg and averaging 4.42 g/kg for the total K,and from 13.9 mg/kg to 362.5 mg/kg and averaging 65.5 mg/kg for the available K.⑥Soil exchangeable calcium was relatively high with a mean of 740.4 mg/kg.⑦Soil exchangeable magnesium was low and averages 68.4 mg/kg.⑧Soil available zinc was high and averaged 1.85 mg/kg.⑨Soil boron was extremely low and averaged 0.128 mg/kg.