Biotic and Abiotic Controls on Soil Inorganic Carbon Dynamics in Arid Ecosystems: A Three-component Study to Evaluate the Effects of Global Change in the Mojave Desert

大多数关于土壤在全球碳(C)循环中的作用的研究都集中在有机碳上。然而，在干旱生态系统中，土壤碳主要以无机碳酸盐矿物的形式存在。驱动碳酸盐转化的两个主要因素是水分和二氧化碳（CO2）浓度，这两者都取决于植物的活动。本研究通过实地研究、温室实验和计算机建模来解决地下植物活动与碳酸盐转化之间的联系。实地研究将在莫哈韦沙漠进行，那里的自然生态系统将暴露于氮沉积、降水和大气二氧化碳浓度增加的环境中。温室研究将允许在更可控的条件下进行实验，而建模将整合从野外和温室获得的知识，以预测未来气候变化下碳酸盐储层的长期变化。这项研究的结果将有助于更好地评估干旱生态系统在全球C循环中的作用。

Most research addressing the role of soils in the global carbon (C) cycle has focused on organic C. In arid ecosystems, however, soil C is predominantly present as inorganic carbonate minerals. The two main factors driving transformation of carbonates are moisture and carbon dioxide (CO2) concentrations, both of which depend on plant activity. This study addresses linkages between belowground plant activity and carbonate transformations using field studies, greenhouse experiments, and computer modeling. The field study will be conducted in the Mojave Desert where natural ecosystems will be exposed to increased nitrogen deposition, precipitation, and atmospheric CO2 concentrations. The greenhouse studies will allow for experimentation under more controlled conditions while the modeling will integrate knowledge obtained from the field and greenhouse to predict long-term changes in carbonate pools under future climate change. Results of this study will allow for better assessment of the role of arid ecosystems in the global C cycle.