秸秆还田及施肥对小麦复种油菜农田土壤呼吸的影响  

Effects of Crop Residue Returning to Field and Fertilizer Application on Soil Respiration in Wheat/rape Field

作　　者：何向南[1,2] 黄高宝[2,3] 黄鹏[2,3] 

机构地区：[1]甘肃农业大学资源与环境学院,甘肃兰州730070 [2]甘肃省干旱生境作物学重点实验室,甘肃兰州730070 [3]甘肃农业大学农学院,甘肃兰州730070

出　　处：《干旱区研究》2012年第6期1003-1008,共6页Arid Zone Research

基　　金：国家科技支撑计划项目(2012BAD14B10)

摘　　要：在甘肃省石羊河绿洲灌区连续3 a的小麦复种油菜田间定位试验的基础上,采用EGM-4密闭式土壤呼吸测量系统,测定了不同施肥水平和不同秸秆还田方式下小麦复种油菜农田的土壤呼吸速率。结果表明:在整个观测期内,土壤呼吸速率最高值出现在8月下旬(152.06～199.58 mg.m-2.h-1),最低值出现在10月中旬(12.67～19.01 mg.m-2.h-1)。土壤呼吸速率日变化呈单峰曲线,最高值出现在12:00—14:00,4:00左右达最低值;不同秸秆还田方式下,高茬收割免耕播种油菜的处理明显降低了土壤呼吸速率,且在秸秆处理后的油菜生育期内降低效果更加明显;不同施肥水平下,在N、P减量15%的情况下,土壤呼吸速率显著下降;各试验处理措施下,土壤呼吸速率与5 cm和10 cm土壤温度、30 cm各层土壤含水量均呈极显著正相关,并且土壤呼吸速率与0～30 cm土壤水分的相关性较土壤温度高;不同处理下土壤呼吸速率与土壤孔隙度基本上呈负相关,但是两者之间相关性并不显著。Based on the three-year field experiment in wheat/rape field in the Hexi Oasis Irrigation Area,the values of soil respiration rate were estimated with the EGM-4 soil respiration measurement system under different fertilizer application levels and ways and crop residue returning to field.The results showed that,throughout the observation period,the maximum value of soil respiration rate（152.06-199.58 mg·m-2·h-1） occurred in late August,and the minimum one（12.67-19.01 mg·m-2·h-1） occurred in mid-October.The curve of daily variation of soil respiration rate was unimodal,the maximum value occurred during the period of 12：00-14：00,and the minimum value appeared around 4：00.The soil respiration rate was significantly reduced under high crop stubble harvest without till,especially during the rape growth period.The soil respiration rate was significantly decreased under the different fertilizer application levels and in the case that N and P fertilizers were reduced by 15%.Under the treatment measures in the experiment,there was an extremely significant positive correlation between soil respiration rate and soil temperatures at soil layers of 5 cm and 10 cm in depth and also the soil moisture content at soil layer of 30 cm in depth.Furthermore,the correlation of soil respiration rate with soil moisture content in soil layer of 0-30 cm was higher than that with soil temperature.There was a negative correlation between soil respiration rate and soil porosity,but their correlation was not significant.

关 键 词：土壤呼吸速率 小麦 油菜 施肥水平 秸秆还田 石羊河 甘肃 

分 类 号：S512.1[农业科学—作物学] S565.4