脐橙果园土壤养分动态与酶活性的季节变化  

Seasonal changes of soil nutrient supply and enzyme activities in navel orange orchards of south Jiangxi

作　　者：郭恢财[1] 廖鹏飞[1] 陈伏生[1] 

机构地区：[1]南昌大学生命科学与食品工程学院,南昌330031

出　　处：《生态学杂志》2010年第4期754-759,共6页Chinese Journal of Ecology

基　　金：江西省自然科学基金项目(2007GQN1935);国家自然科学基金资助项目(30960311)

摘　　要：土壤酶活性可用于衡量土壤养分供应能力及土壤质量,而其季节变化可反映养分供应与植物需求的耦合关系。在赣南地区选取施肥模式类似,种植年限分别为9、20和31年的脐橙果园为研究对象,测定土壤养分含量,监测土壤酶活性的季节变化。结果表明:土壤有机碳(C)、全氮(N)和全磷(P)均表现为随种植年限延长逐渐提高;土壤蔗糖酶活性表现为20年高于9年和31年,脲酶为9年和21年高于31年,而酸性磷酸酶不同种植年限之间差异不显著。土壤C、N、P的转化和供应速率与养分含量提高的变化趋势不一致,种植年限至31年,土壤C和N供应速率均表现出下降的趋势;且土壤蔗糖酶、脲酶和酸性磷酸酶活性的季节变化与脐橙初冬C贮存、春夏N需求和夏末秋初P转移更明显的节律不吻合。因此推断,随着种植年限增加,土壤养分转化和供应速率下降,N和P供应失衡、养分供应的季节变化与果树需求不协调可能是导致赣南高龄果园土壤质量及脐橙产量和品质下降的重要原因。Taking three navel orange orchards varied in stand age but similar in fertilization mode in south Jiangxi as test objects,this paper studied the seasonal changes of their soil nutrient supply and enzyme activities.The soil organic carbon （OC）,total nitrogen （TN）,and total phosphorus （TP） contents all increased with stand age.Soil sucrase activity was higher in the 20-year-old orchard than in the 9-and 31-year-old orchards,soil urease activity was in reverse,and soil acid phosphatase activity had no significant difference among the three orchards.The increase of soil OC,TN,and TP contents with stand age was not consistent with their transformation rates based on the determinations of soil enzyme activities,e.g.,in 31-year-old orchard,the transformation rates of soil C and N had a decreasing trend.In addition,the seasonal changes of soil sucrase,urease,and acid phosphatase activities did not meet the seasonal shifts of the orange tree＇s nutrient demands,i.e.,C accumulation in early winter,N need in spring and summer,and P transfer in late autumn and early winter.It was deduced that the lower transformation rate of soil nutrients,imbalance of soil N and P supply,and inconsistency between the seasonal changes of soil nutrient supply and plant nutrient demand would be the main causes inducing the decrease of productivity and the decline of fruit quality in elder navel orange orchards of south Jiangxi.

关 键 词：长期施肥 赣南脐橙 土壤酶活性 土壤质量 

分 类 号：S666.4[农业科学—果树学]