摘要： 土壤呼吸是陆地生态系统碳循环的重要环节,在维持全球碳平衡中发挥着十分重要的作用。全球气候变暖会改变大气环流和全球水文循环,研究土壤水分状况对土壤呼吸的影响机理对于预测未来土壤碳储量变化具有重要意义。本文通过人为控制灌溉量,研究了灌溉量对灌浆期麦田土壤呼吸的影响,结果表明:在水分亏缺下,土壤呼吸随着灌溉量的增大而增强,但过量灌溉会抑制土壤呼吸,而这种抑制作用会随着时间的推移而消退。Q₁₀与灌溉量之间呈抛物线关系,在灌溉量较小的情况下,Q₁₀随灌溉量的增加而增大,过量灌溉时随灌溉量的增加而减小。

关键词: 土壤呼吸, 灌溉量, Q₁₀, 农田

Abstract: Soil respiration has been shown to be a major contributor to the carbon budget and plays an important role in the global carbon cycle.Global warming is anticipated to alter the patterns of global atmosphere circulation and hydrologic cycling, so it is necessary to study the responses of soil respiration to the precipitation affected by the altered hydrologic cycling.In this study,we controlled the soil moisture by 4 levels of irrigation modeling different precipitation and observed the soil respiration.We found that: one, irrigation could stimulate the soil respiration but much water could reduce the soil respiration rate especially shortly after the irrigation; two, the response of temperature sensitivity( i．E． Q₁₀ ) of soil respiration to the irrigation quantity was curvilinear with apparently less increase in per Q₁₀per unit of increase in irrigation quantity and even decreased at the higher values of irrigation quantity．

Key words: Soil respiration, Irrigation quantity, Q₁₀, Cropland

中图分类号: 

• S152.7