DISSERTATION RESEARCH: Carbon and Nitrogen Dynamics of Southern Great Plains Mixed Grasslands: Impacts of Seasonal Fire and Simulated Herbivory

论文研究：南部大平原混合草原的碳和氮动态：季节性火灾和模拟食草动物的影响

• 批准号: 0309286
• 负责人: Thomas Boutton
• 金额: $ 0.9万
• 依托单位: Texas A&M Research Foundation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-05-01 至 2004-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0309286&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Carbon; Nitrogen; Dynamics

The research proposed here will assess the importance of feedbacks between plant productivity, biomass removal due to fire and herbivory, and element cycling in grassland ecosystems. Conceptual models of interactions among these processes will be evaluated in mixed grasslands of the southern Great Plains. These models are distinguished by the relative importance they assign to feedbacks between plant tissue quality and soil nitrogen mineralization rates. Models emphasizing feedbacks differ in the nature (positive or negative) of specific feedback mechanisms. Models assume minimal importance to feedbacks identify different factors (climate vs. decoupling of C and N cycles) as primary regulators of fertility and plant productivity. Existing data collected by these researchers suggest that that modulation of plant inputs to soils by fire and herbivory limit microbial C pools in these grasslands, thereby minimizing feedbacks to C and N cycling. The investigators request support for analysis of existing plant and soil samples to assess the degree of decoupling between C and N cycling in soil pools.

本文的研究将评估植物生产力，生物量去除由于火灾和草食动物，以及草原生态系统中的元素循环之间的反馈的重要性。 这些过程之间的相互作用的概念模型将在南部大平原的混合草原进行评估。 这些模型的区别在于它们赋予植物组织质量和土壤氮矿化速率之间的反馈的相对重要性。 强调反馈的模型在具体反馈机制的性质（积极或消极）上有所不同。 模型假设最小的重要性，以反馈确定不同的因素（气候与C和N循环的脱钩）作为生育力和植物生产力的主要调节因素。 这些研究人员收集的现有数据表明，通过火和草食动物对土壤的植物输入的调节限制了这些草原中的微生物C库，从而最大限度地减少了对C和N循环的反馈。 调查人员要求支持现有的植物和土壤样本的分析，以评估土壤池中的C和N循环之间的脱钩程度。