关键词: 秸秆覆盖, 土壤呼吸, 土壤温度, 土壤水分

Abstract: [Objective] The aim of the present study was to explore the effects of straw mulching on soil respiration of maize(Zea mays) cropland in the mountain area in North China. [Method] Soil respiration of two treatments(with straw incorporation, TSI and tillage with no straw return, TNS) was measured with Li-8100 carbon efflux system. In addition, the relationships between soil respiration and water and temperature were analyzed. [Results] Changes in soil respiration rates exhibited a single-peaked curve in the two treatments. Soil respiration rates under TSI and TNS were 0.88~2.80 μmol/(m²·s) and 0.71~1.78 μmol/(m²·s), respectively. The pairwise t test showed that soil respiration in the TSI was significantly higher than that in the TNS. Based on exponential function, soil temperature ex plained 82.5% and 69.5% variations of soil respiration in the TSI and in the TNS, respectively. The Q₁₀ of TSI(2.94) was greater than that of TNS(2.18). Soil moisture was related to soil respiration, explaining 88.8% in the TNS and 84.6% in the TSI, respectively. [Conclusion] Straw incorporation increased soil respiration significantly. Quadratic model could well simulate the relationship between soil respiration and soil moisture content. Compared with single-factor equation, two-factor equations(soil temperature and soil moisture) did not improve the explanation of soil respiration to soil temperature and soil moisture content.

Key words: straw mulching, soil respiration, soil temperature, soil moisture