海南西南部不同植被类型样地的土壤养分特性及持水性比较研究

The Comparative Study on the Soil Nutrients and Water-holding Among Different Vegetation Types in the South-west Area of Hainan Island

对海南西南部海尾地区的桉树林、木麻黄林、相思林、灌丛、草地和甘蔗园等6种主要植被类型进行了野外调查和室内分析,研究了其土壤养分和4个不同季节的土壤含水量.结果表明:6种植被类型的土壤养分整体明显偏低,在0～20cm土层,全N为0.0058%～0.0471%,全P为0.0080%～0.0180%,全K为0.0491%～0.1482%,速效N为12.30～63.20mg·kg-1,速效P为9.75～44.63mg·kg-1,速效K为11.25～27.50mg·kg-1,有机质为0.145%～0.878%,pH值为5.55～7.18;灌丛、甘蔗和相思林持水性较好,而桉树林地土壤含水量极差;桉树林、木麻黄和相思林林地土壤有机质含量与含水量、全N含量有一定的相关性.由于桉树林土壤持水能力弱,因此认为该地区不适宜大面积种植桉树,可用灌丛和相思林代替桉树林.

The main types of artificial and nature vegetation are as follows:Eucalyptus forest,Casuarina forest,Acacia forest,corps,shrub and grass.Soil water content and soil nutrients of 6 main vegetation types were studied comparatively in this paper.The results showed that the soil nutrients are very poor.i.e.the content of total N is 0.005 8%-0.047 1%,the content of total P is 0.008 0%-0.018 0%,the content of total K is 0.049 1%-0.148 2%,the content of quick-acting N is 12.30-63.20 mg·kg^(-1),the content of quick-acting P is 9.75-44.63 mg·kg^(-1),the content of quick-acting K is 11.25-27.50 mg·kg^(-1),the content of organic is 0.145%-0.878%,pH is 5.55-7.18 in the lay from 0-20 cm.Water-holding power of Eucalyptus forest is the lowest among these vegetations.For mitigating the dry situation of this region,it should properly plants the shrub and Acacia forest instead of eucalyptus forest.