生态环境研究室知识库

Turfgrass systems represent one major group of intensively managed ecosystems and a potential carbon (C) sink. Turfgrass management practices critically influence C inputs to soil, soil microbial dynamics, and in turn soil C and nitrogen (N) balance. However, how management practices influence soil organic C and microbial dynamics in turfgrass systems is not well understood. We investigated the effect of management duration and intensities on soil microbial biomass, microbial activities and soil organic C contents in two golf courses dominated by Bermuda grass near Raleigh, NC, USA. In Hope Valley, two fairways were studied under the same management scheme but for a huge difference in duration (10 vs. 80 years). Whereas, in Treyburn, rough, fairway, and tee areas that were constructed in the same year but received different N and water inputs, and with different cutting frequencies were examined. Results showed conversion of a pine forest to turfgrass course reduced soil microbial biomass, microbial activities and soil organic C. Long term turfgrass planting accumulated soil organic C and N at rates of 71.9 and 10.6 g m(-2) y(-1) over 80 years. Moderate management intensity resulted in highest soil organic C and microbial biomass C. High N and water inputs stimulated decomposition and reduced the C accumulation in highly managed areas such as the tee area. These results suggest that management practices may critically affect organic C sequestration in turfgrass management systems.