PRF/J: Nutrient Cycling as a Measure of Agroecosystem Sustainability

PRF/J：养分循环作为农业生态系统可持续性的衡量标准

• 批准号: 9303261
• 负责人: Erle Ellis
• 金额: --
• 依托单位: DC Fellowships
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-08-01 至 1996-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9303261&HistoricalAwards=false
• 关键词: PRF; Nutrient; Cycling; Measure; Agroecosystem

This project will relate nutrient cycling to long term productivity of agroecosystems by comparing nutrient cycles that prevail under agricultural methods in ancient and complex Chinese agroecosystems with those of conventional farms. With nitrogen often being the limiting nutrient in such systems, nitrogen (N) - cycling is the main focus of the study, with other nutrient cycles to be also characterized where useful. N-cycling patterns are to be modeled from annual N-transfer budgets of village-scale agroecosystems. Food web and trophic chain models of N-cycling will be compared for their ability to differentiate agroecosystem behaviors, and various calculations will be assessed for their suitability in quantifying nutrient cycling. A nitrogen-recycling-efficiency index will be derived from N-cycling measures combined with input/output efficiency criteria and soil N pool size. This index will be related to ecological sustainability using as a benchmark Chinese agroecosystems that have sustained high yields for centuries. The contemporary importance of legume cultivation to sustained agroecosystem productivity will then be evaluated using the N- recycling index. %%% Traditional Chinese agroecosystems and the eco-farms derived from them are striking examples of environmental management based upon ecological principles. Nutrient cycling patterns of such systems provide an excellent contrast to Chinese farms that use only conventional chemical nutrient management. All three agroecosystem types (traditional, eco-farm, conventional) may be found in the same bioclimatic area of China; the combination of all three types in a comparative study constitutes a unique opportunity to develop measurements of sustainability.

这个项目将养分循环与长期生产力联系起来 通过比较不同环境下普遍存在的养分循环来研究农业生态系统 中国古代复杂农业生态系统中的农业方法 与传统农场相比。 氮通常是 限制营养素在这样的系统中，氮（N）循环是 研究的主要重点，与其他营养循环也 在有用的地方进行表征。 N-循环模式将被建模 从村规模农业生态系统的年度氮转移预算。 食物网和营养链模型的N-循环将进行比较， 他们区分农业生态系统行为的能力，以及各种 将评估计算在定量方面的适用性 养分循环 氮循环效率指数将是 从N循环度量与输入/输出相结合导出 效率标准和土壤氮库大小。 该指数将 与生态可持续性相关的标准， 几个世纪以来一直保持高产的农业生态系统。 的 豆科植物种植对可持续发展的当代重要性 农业生态系统的生产力，然后将评估使用N- 循环指数 %%% 中国传统农业生态系统及其衍生的生态农场 它们是环境管理的突出例子， 生态原则。 这类系统的养分循环模式 这与中国的农场形成了鲜明对比， 常规化学养分管理。 三大农业生态系统 类型（传统，生态农场，常规）可以在 中国同一生物气候区;三种类型的组合 在一项比较研究中， 衡量可持续性。