秸秆覆盖对冀北山区夏玉米土壤呼吸的影响

发布时间：2018-06-26 01:39

本文选题：秸秆覆盖 + 土壤呼吸　；参考：《四川农业大学学报》2016年02期

【摘要】：【目的】揭示北方山区秸秆覆盖对旱作玉米田土壤呼吸的影响。【方法】以北方山区夏玉米田为研究对象,采用Li-8100土壤碳通量系统测定了无秸秆覆盖和秸秆覆盖2种条件下土壤呼吸速率的生长季变化特征,分析土壤呼吸速率与水热因子的关系。【结果】在玉米生长季内,土壤呼吸速率呈单峰型变化趋势;秸秆覆盖和无秸秆覆盖的土壤呼吸速率变化范围分别为0.88~2.80μmol/(m2·s)和0.71~1.78μmol/(m2·s),秸秆覆盖土壤呼吸速率显著高于无秸秆覆盖;土壤呼吸与10 cm深处的土壤温度呈显著的指数相关,秸秆覆盖和无秸秆覆盖的土壤温度可以分别解释土壤呼吸变化的82.5%和69.5%;基于土壤温度计算的敏感性指数Q10值为秸秆覆盖(2.94)无秸秆覆盖(2.18);土壤呼吸对土壤水分的响应符合一元二次函数模型,无秸秆覆盖和秸秆覆盖的土壤含水率可以解释土壤呼吸变化的88.8%和84.6%;水热双因子模型的拟合结果比单因子模型较差。【结论】秸秆覆盖显著增加了土壤CO2排放,土壤含水率能更好地解释土壤呼吸速率的变化,水热双因子的协同影响机制有待进一步研究。
[Abstract]:[objective] to reveal the effect of straw mulching on soil respiration in dry maize field in northern mountainous area. [methods] Summer corn field in northern mountainous area was taken as the research object. Li-8100 soil carbon flux system was used to measure the seasonal variation characteristics of soil respiration rate under two conditions of no straw mulching and straw mulching, and to analyze the relationship between soil respiration rate and water and heat factors. [results] in maize growing season, the relationship between soil respiration rate and water heat factor was analyzed. The variation range of soil respiration rate in straw mulching and non-straw mulching was 0.880.80 渭 mol/ (m 2 s) and 0.71 s), 1.78 渭 mol/ (m 2 s), respectively, which was significantly higher than that without straw mulching. Soil respiration was exponentially correlated with soil temperature at a depth of 10 cm. The soil temperature with straw mulching and without straw mulching can explain 82.5% and 69.5% of soil respiration, the sensitivity index Q10 calculated based on soil temperature is straw mulch (2.94), no straw mulch (2.18), and the response of soil respiration to soil moisture. It should conform to the quadratic function model of one variable, The soil moisture content without straw mulching and straw mulching could explain 88.8% and 84.6% of soil respiration, and the fitting results of water and heat double factor model were worse than that of single factor model. [conclusion] Straw mulching significantly increased soil CO2 emission. Soil moisture content can better explain the change of soil respiration rate, and the synergistic mechanism of water and heat factors need to be further studied.
【作者单位】：河北省科学院地理科学研究所;中国科学院遗传与发育生物学研究所农业资源研究中心;
【基金】：河北省自然科学基金项目(C2015503008) 河北省科学院高层次人才项目(20150503LR62-1)
【分类号】：S513;S154

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