长期施氮与灌溉对毛白杨人工林土壤硝态氮分布与积累的影响  

Effects of Long-term Irrigation and Nitrogen Application on Distribution and Accumulation of Soil Nitrate in Populus tomentosa var. tomentosa Plantations

作　　者：张润哲 朱嘉磊[1] 王江 聂浩亮 黄梦遥 宋连君 聂立水[1] ZHANG Run-zhe;ZHU Jia-lei;WANG Jiang;NIE Hao-liang;HUANG Meng-yao;SONG Lian-jun;NIE Li-shui(College of Forestry,Beijing Forestry University,Beijing 100083,China;Weixian Nursery,Xingtai 054700,Hebei,China)

机构地区：[1]北京林业大学林学院,北京100083 [2]威县苗圃场,河北邢台054700

出　　处：《林业科学研究》2019年第6期7-13,共7页Forest Research

基　　金：十二五"国家科技支撑计划资助(2015BAD09B02)

摘　　要：[目的]研究灌溉和施氮对硝态氮在毛白杨林地土壤中积累与分布的影响,为毛白杨速生丰产林科学精准施肥和减少硝态氮淋失提供依据。[方法]在华北平原毛白杨适生地河北威县,利用"十二五"毛白杨大径材培育研究长期试验地,研究了通过灌溉保持不同土壤水分状况(田间持水量45%、60%、75%)和施氮量(0.0、101.6、203.2、304.8 kg·hm^-2)对土壤硝态氮分布与积累的影响。[结果]土壤硝态氮分布具有明显的表聚性,在0~200 cm土层呈先下降后上升再下降的"S"型变化趋势,且施氮量越大,硝态氮在60~100 cm土层累积的趋势越明显。随着土壤水分的增加,土壤硝态氮的淋洗峰所在土层深度分别在40~60、60~80、80~100 cm。土壤硝态氮累积量随施氮量的增加而增加,随灌水量的增加则呈先增加后减少的趋势;水氮交互作用对硝态氮的分布与积累影响显著。林地不同水氮组合土壤硝态氮积累量为86.11~259.29 kg·hm^-2。[结论]施氮量与土壤水分含量对毛白杨林地土壤硝态氮的分布与积累影响显著,在0~200 cm土层内,随着施氮量的增加,硝态氮的积累量呈上升趋势;随着土壤含水量的增加,硝态氮积累峰所在的土层呈逐渐下移的趋势。与农田生态系统相比,试验林地0~200 cm土层内硝态氮积累量较低,林地生态系统庞大林木根系对硝态氮吸收作用值得重视。同时,为了减少硝态氮的淋失,建议减少氮肥的施用,并将田间持水量控制在60%~75%。[Objective]To investigate the effects of irrigation and nitrogen application on soil nitrate accumulation and distribution,so as to provide visions for specific irrigation and fertilization management principles and guidelines as well as reducing nitrate leaching in intensively managed Populus tomentosa var.tomentosa industrial plantation.[Method]The study site locates in Weixian County of Hebei Province where a long-term irrigation and fertilization supported by“12th Five-Year Plan”research project has been initiated with aims to improve timber production.By maintaining the soil water content above different field water holding capacity(45%,60%,75%)and different nitrogen application rate(0.0,101.6,203.2,and 304.8 kg hm^-2),the distribution pattern and accumulation of soil nitrate were studied.[Result]Soil nitrate content had an obvious surface accumulation tendency.From 0-200 cm,the soil nitrate content followed a S-shaped pattern(decrease-increase-decrease).The higher rate the nitrogen,the more the accumulation of nitrate in the soil layer between 60-100 cm.With the increase of soil moisture level,the leaching peak of soil nitrate was going down to 40-60,60-80,and 80-100 cm,respectively.The nitrate accumulation in soil increased with the increase of nitrogen application rate.With the increase of soil moisture level,the soil nitrate showed an up then down pattern.Meanwhile,the water and nitrogen had a significant positive interaction on the distribution and accumulation of nitrate.In this study,different combinations of water and nitrogen of the soil nitrate accumulation ranged from 86.11-259.29 kg hm^-2.[Conclusion]Nitrogen application and soil moisture levels have significant effects on the distribution and accumulation of soil nitrate in the P.tomentosa var.tomentosa stand.With the increase of nitrogen application rate,the soil nitrate shows a tendency to build up in the soil layer between 0-200 cm.With the increase of irrigation level,the soil nitrate accumulation peak tends to move downward gradually.Co

关 键 词：硝态氮 施氮量 田间持水量 毛白杨 农田生态系统 林地生态系统 

分 类 号：S718.5[农业科学—林学]