摘要
为明确外源有机物质和无机碳酸盐对桂西北石灰土土壤有机碳矿化的影响,加深对土壤有机碳周转特征的认识,本文以广西环江县喀斯特地区的棕色石灰土、黑色石灰土和地带性红壤(对照)为研究对象,进行为期100d的室内培养试验[对照(无外源物添加,CK)、添加14C-稻草(S)、添加Ca14CO3(C)],并对土壤呼吸释放的CO2及14C-CO2含量进行测定。结果表明:培养100d后,外源物的添加均明显促进了红壤、棕色和黑色石灰土有机碳的矿化,外源14C-稻草和Ca14CO3对上述土壤有机碳矿化的激发效应分别为28.7%、46.2%、15.5%和127.0%、175.3%、100.1%;土壤表观累积矿化量中外源Ca14CO3的贡献率分别为40.4%、48.4%、19.6%;土壤类型和添加物及两者间的交互作用均对土壤有机碳矿化的激发效应、土壤表观累积矿化量中外源物的贡献、土壤有机碳的矿化速率、土壤有机碳累积矿化量/率有显著影响。因此,外源有机物质和碳酸钙的添加改变了土壤有机碳的矿化特征,对于含碳酸盐的石灰土,研究土壤有机碳矿化、周转规律,评估其对大气CO2的影响必须考虑无机碳酸盐的贡献。
To elucidate the effects of exogenous organic substrate and calcium carbonate on the organic carbon mineralization in lime soils and to deepen the understanding of the characteristics of soil organic carbon turnover,the terra fusca,rendzina,and zonal red soil were collected from the Karst region in Huanjiang of Guangxi,and a 100-day incubation experiment was conducted,with the fluxes of CO2 and 14C-CO2 from the soils determined.Three treatments were installed,i.e.,no exogenous addition（CK）,addition of 14C-labeled rice straw（S）,and addition of 14C-labeled calcium carbonate（C）.In treatments S and C,the mineralization of soil organic carbon was promoted obviously,and the priming effect of 14C-labeled rice straw and 14C-labeled calcium carbonate on the organic carbon mineralization in the terra fusca,rendzina,and zonal red soil after 100-day incubation was 28.7%,46.2%,and 15.5%,and 127.0%,175.3%,and 100.1%,respectively.In the apparent cumulative mineralization,the contribution rate of 14C-labeled calcium carbonate in the terra fusca,rendzina,and zonal red soil was 40.4%,48.4%,and 19.6%,respectively.Soil type,exogenous additives,and their interaction had significant effects on the priming effect of the soil organic carbon mineralization,the contribution of the additives to the apparent cumulative mineralization,and the cumulative mineralization volume（or rate）（P0.01）.This study indicated that the addition of exogenous organic substrate and calcium carbonate altered the characteristics of soil organic carbon mineralization,and,as for the lime soils,the contribution of inorganic carbonate should be taken into consideration in the study of the mineralization and turnover of soil organic carbon and the assessment of their effects on atmosphere CO2.
出处
《生态学杂志》
CAS
CSCD
北大核心
2012年第11期2748-2754,共7页
Chinese Journal of Ecology
基金
中国科学院战略性先导科技专项(XDA05070403)
中国科学院西部行动计划项目(KZCX2-XB3-10)
国家自然科学基金项目(30970538和41171246)
中国科学院亚热带农业生态研究所青年人才领域前沿项目(ISACX-LYQY-QN-1101)资助
关键词
喀斯特
土壤有机碳矿化
激发效应
无机碳
14C示踪技术
Karst
soil organic carbon mineralization
priming effect
inorganic carbon
14C tracer technique.
