三峡库区脐橙园土壤养分、酸度变化特征与施肥管理对策——以秭归县水田坝乡为例

An investigation was conducted from 2005 to 2006 on soil nutrients contents and acidity for hillside orange garden in Shuitianba Town in the Three Gorges Region. Soil organic matter content, total nutrients contents (N, P and K), available nutrients contents (N, P, K, Zn, Fe, Mn and Cu) and soil acidity (pH, exchangeable acidity) were analyzed and elucidated, the correlations between the available macro-element contents and soil pH were revealed. The results showed that a great uneven distribution of soil nutrients and soil organic matter, attributed to the great slope degree, the intensive cultivation in the last century, the complexity of parent material distribution, and the current soil fertilization. The deficiency of organic matter, total N and P, and abundance of total K, about 65% of the sampled soil deficient in available N, 45% deficient in available P and K, and 45% deficient in available Zn. With the increase of continuous orange cultivation year, continuous fertilization increased soil available nutrients contents but enhanced soil acidification, therefore, suitable measures in fertilization should be taken to prevent soil deterioration.