海南雅星林场芒果园间作生态系统养分循环研究初报

对海南儋州雅星林场4龄芒果园的4种间作模式土壤中养分流失、养分淋失、氨挥发、养分输送循环等进行研究。结果表明:果园不同生态系统中,间作柱花草模式养分盈余最大,达到349.8kg/hm2,养分再循环量大,有利于果园不断的培肥;间作木薯模式养分盈余最少,只有7.64kg/hm2;而只有间作木薯模式的P,K和间作番薯—花生模式的N素才处于亏损状态,分别亏缺2.32kg/hm2 ,2.34kg/hm2 ,7.78kg/hm2。在果园生态系统中,不同养分损失量大小顺序为:有机质>速效钾>全氮>水解氮>速效磷。不同季节施肥(尿素),NH3挥发损失有明显的差异。随着N肥施用量的增加,N的淋失量呈现显著或极显著性增加。

Preliminary Report on the Nutrient Cycling in the Mango-Based Intercropping Ecosystems at Yaxin Forestry Farm of Hainan

A study on cycling of N,P and K nutrient elements was carried out in the intercropping systems of four-year mango plantations.The results showed that the nutrient gain(349.8kg/hm 2 )and the nutrient cycling was the highest in mango tree+S.guianensis intercropping system among the ecosystems,whereas the nutrient gain was the least(7.64kg/hm 2 )in mango tree+cassava intercropping system.Only the mango+sweet potato -peanut intercropping system and the mango+cassava intercropping system had deficits of N,P and K(2.32kg/hm 2 ,2.34kg/hm 2 ,7.78kg/hm 2 respec tively).The nutrient loss through erosion was organic matter>available K>total N>hydrolysable N>available P.Nutrient loss changed obviously with season.The loss of NH 3 volatilization was significantly different in seasons when fertilizer(urea)was applied.The loss of N by percolation increased significantly or highly significantly with the fertilizer application.