effect of continuous cropping on soil chemical properties and crop yield in banana plantation

the effects of banana continuous cropping on soil quality and chemical properties and crop yield were investigated under continuous cropping for 1, 3, 5, 7, 10, and 15 years in hainan province, china. the results indicated that the contents of total n, total k, available k, nh4-n, exchangeable ca, and available cu tended to increase, while total organic c (toc), available s, and available zn tended to decrease with the increase of continuous cropping years at the four sampling stages. the contents of exchangeable mg and available fe and mn were higher in the 3, 5, 7, and 10 years than in the 1 and 15 years at the four sampling stages. the values of ph, the contents of total p and available p decreased from 1 to 5 years and increased from 7 to 15 years at most of the sampling stages. overall, average banana yield increased from 1 to 3 years and decreased afterwards. in conclusion, banana continuous cropping deteriorated soil quality as evidenced by increase of soil acidity, decrease of total organic c, accumulation of n, p, k, ca and cu, deficiency of mg, s, fe, mn, and zn and accompanying decline in banana yield. in order to improve the soil environment and sustain higher productivity under continuous-banana cropping system, application of balanced rate of fertilizers is of considerable importance.