Microbial Changes Associated with Renovated Soils: Nutrient Cycling in Subtropical Agroecosystems

拟议的研究分两个阶段进行：第一阶段将集中于 控制微生物变化的机制 以一种详细的、具体的控制方式对土壤进行修复， 温室或生长室系统。 第二阶段将重点关注碳 和氮动力学，以及相关的微生物变化，在 皮埃蒙特景观使用稳定同位素。 本研究的目标是： 1.为了测量氮的吸收和回收的百分比， 受时间、侵蚀/质地水平 表面放置的残留物，以及聚集体的形成和稳定 在皮埃蒙特的农业生态系统中。 2.为了更好地了解内部动态循环， 通过使用同位素示踪剂15 N来测量微生物的氮含量， 氮以及其他池在特定的时间间隔。 3.研究了氮肥对土壤残留氮的影响， 以及这个过程如何影响矿化作用- 固定化周转率。

The proposed research is in two phases: phase I will focus on mechanisms controlling microbial changes associated with the renovation of soils in a detailed, specific controlled fashion in a greenhouse or growth chamber system. Phase II will focus on carbon and nitrogen dynamics, as well as associated microbial changes, in the Piedmont landscape using stable isotopes. The objectives of this research are: 1. To measure the uptake and the percentage of nitrogen recovered by the summer grain crop as affected by time, erosion/texture levels, surface placed residues, and aggregate formation and stabilization in the Piedmont agroecosystems. 2. To gain a better understanding of the internal, dynamic cycling of nitrogen by using an isotope tracer, 15N, to measure microbial nitrogen as well as other pools at specific time intervals. 3. To measure the effect of fertilizer N on residue N retention and release and how this process affects mineralization - immobilization turnover rates.