Numerous studies with wide-ranging results have been conducted to resolve if Great Plains soils are a C source or sink. The authors addressed the source/sink question by examining the results from producer soil samples and production surveys that were analyzed and archived by the South Dakota Soil Testing Laboratory. Results showed that between 1985 and 2010, soil organic C content increased at a rate of 326 lb C/A/year, for a total increase of 24%. The increase was attributed to planting better adapted varieties and using better management practices that on average increased corn grain yields 2.29 bu/A/year. Higher soil organic C has impacts on water quality, soil productivity, and plant nutrition. For example, if we assume that the C:N ratio of organic matter is 10:1, then these findings would indicate that soils during this 25-year period were a sink for both C and N, and could have influenced the N needed to optimize crop yields
展开▼
机译：为了解决大平原土壤是碳源还是汇的问题，已经进行了许多广泛的研究。作者通过检查生产者土壤样本和生产调查的结果解决了源/汇问题，这些样本是由南达科他州土壤测试实验室分析和存档的。结果表明，从1985年到2010年，土壤有机碳含量以326 lb C / A /年的速度增加，总量增加了24％。产量的增加归因于种植了适应性更强的品种并采用了更好的管理方法，玉米平均单产提高了2.29布/年/年。较高的土壤有机碳会影响水质，土壤生产力和植物营养。例如，如果我们假设有机物的C：N比率为10：1，那么这些发现将表明，在这25年的时间里，土壤既是C和N的汇聚区，又可能影响了N优化农作物产量
展开▼
