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Mechanical sampling was used to set 95 plots in eucalypt plantations in Guangdong Province. Ring knife method was used to study soil physical properties, such as soil bulk density, soil capillary porosity, non-capillary porosity, soil maximum water. Soil chemical analysis method was used to determine the contents of soil organic matter, total N, total P, total K, alkalized N , available P and available K. According to the parent rocks developing soils, 95 soils were combined into the soils developed from granite, limestone, purple sandstone, sandshale and basalt. Meanwhile, they were divided into silty loam, glueing loam, course-sand soil, fine-sand soil, face sandy soil, silty clay, sandy clay, clay and loam clay according to “Classification of Soil Texture in China”. Using cluster analysis, soil fertilities were divided into four types: the first group included silty loam, silty clay and loam clay, which had relative high available K, median available P, and other nutrients ranked forefront, soil density and capillary porosity were median, so that their fertility was high; the second group included glueing loam, which had the highest available K, median alkalized N, whereas other nutrients were relative low, soil density was small, capillary porosity was great and non-capillary porosity was median, so that their fertility was median; the third group included course-sand soil, fine-sand soil, face sandy soil and sandy clay, most of which had low soil organic matter, total N, total K, alkalized N and available K, and available P contents of some plots were high, soil density was great with small capillary porosity, resulting their low soil fertility; the fourth group included clay with high fertility, its soil organic matter, total N, total P, alkalized N and available P contents were the highest among the nine type soils
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