不同施氮水平对‘库尔勒香梨’园土壤N_2O排放的影响  

Effects of different nitrogen application levels on nitrous oxide emission from the soil of a ‘Kuerlexiangli' pear orchard

作　　者：王成[1] 陈波浪[1,2] 玉素甫江.玉素音 王前登 柴仲平 刘雪艳[1] WANG Cheng;CHEN Bolang;Yusufujiang Yusuyin;WANG Qiandeng;CHAI Zhongping;LIU Xueyan(College of Pratacultural and Environmental Science,Xinjiang Agriculture University,Urumqi 830052,Xinjiang,China;Xinjiang Key Laboratory of Soil and Plant Ecological Process,Urumqi 830052,Xinjiang,China)

机构地区：[1]新疆农业大学草业与环境科学学院,乌鲁木齐830052 [2]新疆土壤与植物生态过程实验室,乌鲁木齐830052

出　　处：《果树学报》2018年第11期1353-1362,共10页Journal of Fruit Science

基　　金：国家自然科学基金(31460548);自治区自然科学基金面上项目(2017D01A38);自治区青年科技创新人才培养工程(QN2016YX0670);土壤学新疆维吾尔自治区重点学科资助项目

摘　　要：【目的】探寻不同施氮处理对香梨园土壤N_2O排放的影响。【方法】在香梨年生育期内,采用静态箱-气相色谱法对6 a树龄的‘库尔勒香梨’园进行定位监测。设置5个施氮水平:不施肥(N0P0K0)、不施氮肥(N0PK)、低氮量150kg·hm^(-2)(N1PK)、中氮量300 kg·hm^(-2)(N2PK)、和高氮量450 kg·hm^(-2)(N3PK)。【结果】不同施氮处理N_2O排放通量在一天不同时段表现为夜间(20:00—8:00)<上午(8:00—12:00)<中午(12:00—16:00)<下午(16:00—20:00);N_2O排放日累积量表现为:夜间<白天。不同施氮处理(N0P0K0、N0PK、N1PK、N2PK、N3PK)年生育期土壤N_2O累积量分别为341.616、346.548、437.000、459.748、531.960 g·hm^(-2)·a-1。施氮量在450 kg·hm^(-2)时,N_2O排放通量(下午)、日累积量、年生育期累积量均显著大于其他各处理。温度、灌水、施用氮肥均能影响土壤N_2O的排放,其中施用氮肥对土壤N_2O的排放影响最大,土壤N_2O的排放量随着施氮量的增加而增加。施氮量为150、300和450 kg·hm^(-2)时,N_2O排放系数分别为0.060%、0.038%和0.041%。【结论】随着氮肥(尿素)施用量的增加,N_2O排放系数先减小再增大,在尿素施用量为300kg·hm^(-2)(纯N)时,土壤N_2O排放系数最小(0.038%)。【Objective】‘Kuerlexiangli＇pear is a characteristic fruit industry in Xinjiang, where there is a large scale production. However, nitrogen content in the soils is low in‘Kuerlexiangli＇pear orchards. Through the application of nitrogen fertilizer, soil nitrogen contents can be increased to meet the nitrogen demands of pear trees. In order to increase the yield of‘Kuerlexiangli＇pear, farmers often use large amounts of fertilizer, which are excessive for the demands of pear trees. Excessive fertilization leads nitrogen enrichment in the soil, and reduces nitrogen use efficiency. The surplus nitrogen in the soil will be converted into ammonia and nitrogen oxides, which will re-enter the atmosphere, causing air pollution, intensifying greenhouse effect, and leading to a series of ecological and environmental problems. Therefore, we studied the effects of different nitrogen treatments on soil N2O emissions with in-situ field monitoring and indoor analysis, and determined the appropriate amount of nitrogen for pear orchard soil.【Methods】We conducted fertilization experiments with different amount of nitrogen fertilizer in a 6-year-old‘Kuerlexiangli＇pear orchard. Five nitrogen treatments were applied： nofertilizer（N0 P0 K0）, no nitrogen fertilizer（N0 PK）, low nitrogen amount 150 kg· hm（-2）（N1 PK）, medium nitrogen amount 300 kg· hm（-2）（N2 PK） and high nitrogen amount 450 kg· hm（-2）（N3 PK）. During the growth period of pear trees（from April to September）, the N2O emissions from the soil in the pear orchard were collected and monitored by applying the static box-gas chromatography method.【Results】In different nitrogen treatments, N2O emission flux was lowest at night（20：00—8：00）, followed in an increasing order by that in morning（8：00—12：00）, at noon（12：00—16：00） and in the afternoon（16：00—20：00）, and the range of change was from 0.060 to 0.310 g· hm（-2）· h-1. In April and June, the N2O fluxes of soils treated wi

关 键 词：'库尔勒香梨’ 氮肥 氧化亚氮 累积量 排放系数 

分 类 号：S661.2[农业科学—果树学]