农业环境科学学报Issue(7)：1414-1421,8.DOI:10.11654/jaes.2015.07.026
施用硫酸铵对黄土高原地区不同类型土壤CO2释放的影响
Effect of Ammonium Sulfate Application on CO2 Emissions from Four Different Soils in Loess Plateau
摘要
Abstract
Large emissions of greenhouse gases have caused the global temperature increase. CO2 is one of the most important greenhouse gases. Calcareous soils are rich in calcium carbonate, which may release CO2. Soil pH and calcium carbonate content are often deemed to be important factors controlling soil inorganic carbon turnover. Here airtight culture method was adopted to evaluate the role of applying ammo-nium sulfate[(NH4)2SO4] fertilizer on CO2 emissions from four different calcareous soils from Loess Plateau. These soils are Lou soil, dark loessial soil, loessial soil and aeolian sandy soil varying in SOM, pH, texture and carbonate content. The soils were incubated under closed-jar conditions for 46 days at 25℃with and without 1000 mg·kg-1 mercury chloride(HgCl2)buffered by piperazine-1,4-bisethanesulfonic acid(PIPES). Under non-sterilized condition,(NH4)2SO4 application decreased soil pH and NH+4 content. However, sterilization effectively inhibited the nitrification process, thus alleviating soil pH reduction and resulting in NH+4 accumulations in soil. After 46 days of incubation, applying(NH4)2SO4 funder non-sterilized condition increased CO2 emissions by 26.9%, 19.5%, 68.8%and 46.1%for Lou soil, dark loessial soil, loessial soil, and aeolian sandy soil, respectively, compared to control soils(no fertilization). Sterilization obviously decreased CO2 re-leases, implying restrained soil organic mineralization. However,(NH4)2SO4 treatments still increased CO2 emissions from four sterilized soils by average 25.5% in comparison to no(NH4)2SO4 soils. Our results suggest that the main mechanism for CaCO3 dissolution was pro-tons produced by nitrification under non-sterilized condition, while it was H2SO4 under sterilized conditions. The partial pressure of soil so-lution might also leads to release of CO2. Our study confirmed that CO2 released from calcareous soil during the incubation may be from both soil organic carbon and soil inorganic carbon. Ignoring this inorganic process would result in overestimation of mineralization of soil organic carbon.关键词
土壤类型/碳释放/灭菌/无机碳/矿质态氮/土壤pHKey words
soil type/carbon emission/sterilization/inorganic carbon/mineral nitrogen/soil pH分类
农业科技引用本文复制引用
孟延,蔡苗,师倩云,周建斌..施用硫酸铵对黄土高原地区不同类型土壤CO2释放的影响[J].农业环境科学学报,2015,(7):1414-1421,8.基金项目
国家自然科学基金项目（31372137）；国家“十二五”科技支撑计划课题 （）
