季节性冻融作用对不同栽植年限及不同土层苹果梨园土壤pH值和有机碳变化的研究

Study on the effect of seasonal freezing and thawing on changing of soil pH and organic carbon in apple-pear orchard

为阐明季节性冻融作用对苹果梨园土壤pH值和有机碳的影响,于秋季和春季在延边朝鲜族自治州龙井市选取栽植年限为11、25、40、50、63年的苹果梨园土壤布置剖面点,按0~20、20~40、40~60cm分层采集样品。分别对苹果梨园土壤pH值、有机质含量和活性有机碳含量进行了测定。结果表明:季节性冻融对pH值、有机质和活性有机碳影响显著。受季节性冻融作用影响,在0~20和20~40cm土层,各栽植年限土壤pH值普遍上升,在40~60cm土层,pH值普遍下降。其中,在20~40cm土层,25年栽植年限pH值提高了23%,受季节性冻融作用影响最大。各个土层各栽植年限土壤有机质含量下降,其中,在0~20cm土层,25年栽植年限有机质含量下降了34.2%,受季节性冻融作用影响最大。各个土层各栽植年限土壤活性有机碳含量普遍下降,在40~60cm土层,40年栽植年限活性有机碳含量下降了49.4%,受季节性冻融作用影响最大。研究表明,经历冻融后,果园土壤pH值普遍上升而有机质含量和活性有机碳含量普遍下降。

In order to elucidate the effects of freezing and thawing action on soil pH and organic carbon in apple-pear orchard.In autumn and spring,the soil profile of apple pear orchard with planting years of 11,25,40,50 and 63 years was selected in Longjing,Yanbian Korean Autonomous Prefecture,and soil samples of 0-20 cm,20-40 cm,40-60 cm layers under ground were collected.The soil pH,organic matter content and active organic carbon content in apple pear orchard were determined.The results showed that under the influence of seasonal freezing and thawing,the pH of soil in the 0-20 cm and 20-40 cm soil layers generally increased,while that in the 40-60 cm soil layers generally decreased.In the 20-40 cm soil layer,the pH of soil with 25 years of planting increased by 23%,which was most affected by seasonal freezing and thawing.The organic matter content of the soil decreased in each soil layer during the planting period.Among these,the organic matter content in the 0-20 cm soil layer with 25 planting years decreased by 34.2%,which was most affected by seasonal freezing and thawing.The content of soil active organic carbon decreased generally in each soil layer,and the content of active organic carbon in the 40-60 cm soil layer decreased by 49.4%,which was most affected by seasonal freezing and thawing.Seasonal freezing and thawing significantly effected on organic matter,followed by active organic carbon and pH.The soil pH of the orchard generally increased while the content of organic matter and active organic carbon generally decreased after freezing and thawing cycle.