不同施氮水平下旱作玉米田土壤呼吸速率与土壤水热关系  

Effects of Different Levels of N Fertilizer on Soil Respiration, and Its Relation to Soil Moisture and Soil Tem-perature Under Rainfed Land of Summer Maize

作　　者：张俊丽[1] 廖允成[1] 曾爱[1] 刘杨[1] 林杰[1] 王永平[1] 

机构地区：[1]西北农林科技大学农学院,陕西杨凌712100

出　　处：《农业环境科学学报》2013年第7期1382-1388,共7页Journal of Agro-Environment Science

基　　金：国家自然科学基金项目(31071375;31171506);西北农林科技大学国际科技合作项目;西北农林科技大学基本科研业务费专项资金项目;高等学校学科创新引智计划(B12007)

摘　　要：为探讨不同施氮量对旱作玉米田土壤呼吸速率的影响,设置0(CK)、80、160、240、320kg·hm-25个氮肥水平,分析不同施氮水平下土壤呼吸速率动态变化及其与土壤温度和土壤含水量间的关系。结果表明:夏玉米生长季土壤呼吸速率呈单峰变化曲线,于播种后52d左右达到最大值,成熟收获时降至最低;土壤呼吸总量(Sr)与施氮量(n)满足关系式Sr=1204.09(/1+e-1.69-0.02n)。土壤温度和土壤水分是影响土壤呼吸速率的主要因素,5cm土壤温度与土壤呼吸速率呈显著正相关,土壤呼吸速率随土壤温度升高呈指数增加,土壤温度可以解释旱作农田土壤呼吸速率季节变化的62.31%～78.66%;土壤水分和温度相互协调共同调控土壤呼吸,两者可以解释旱作玉米田土壤呼吸季节变化的79.63%～85.87%。An experiment was conducted to explore the effects of different levels of nitrogen fertilizer on soil respiration and on the factors which affecting the soil respiration, especially soil moisture and soil temperature, in the arid condition. Summer maize crop was planted by applying the five different N fertilizer levels, including 0 kg N·hm-2（CK）, 80 kg N·hm-2（N1）, 160 kg N·hm-2（N2）, 240 kg N·hm-2（N3）and 320 kg N·hm-2（N4）. Data regarding average soil respiration showed a single peak curve. maximum respiration rate was recorded after 52 days of planting and the minimum was recorded near to maturity stage. Soil respiration increased with the increase of nitrogen fertilizer level. The equation i.e. Sr=1 204.09 /（1＋e-1.69-0.02n） was used to measure the total amount of soil respirations by applying the different levels of N fertilizer. Minimum total soil respiration was recorded in case of CK, while maximum but statistically at par respirations were recorded in case of N3 and N4. Soil temperature and soil moisture significantly affected the soil respirations. There was a significant positive correlation between 5 cm soil depth temperatures and soil respiration. Soil respiration exponentially increased with the increase of soil temperature, and 62.31%-78.66% variations in it were recorded due to the seasonal variations. Soil temperature and soil moisture interacted with each other and ultimately affected soil respirations. Both two factors showed 79.63%-85.87% variations in seasonal soil respirations from the field under the rained condition.

关 键 词：土壤呼吸速率 氮肥 夏玉米 旱作农田 土壤温度 土壤含水量 

分 类 号：S152.6[农业科学—土壤学]