Average soil nitrogen: Effect of N Addition on Vegetation with Mammalian Herbivory

The purpose of this experiment is to look at the effect of NH4NO3 addition in an unfenced area. The experiment is located in field E. There are 4 different treatments C, F, H, and I as defined in fertilization details in the "microplot" strategy. The plots are 4 by 4 meters and are laid out in an 8 by 8 grid with 1 meter aisles. From 1989-1994 plots with fertilizer treatment 1 were treated as complete controls, receiving no nutrients at all.本试验旨在探究硝酸铵（NH4NO3）添加在无围栏区域中的效应。试验设置于E号田块内。共设置C、F、H、I四种不同处理，具体施肥细节详见“微区（microplot）”试验策略说明。各试验小区面积为4米×4米，以8×8网格布局排列，小区间预留1米宽的通行过道。1989年至1994年期间，施加肥料处理1的小区作为完全对照组，不施加任何营养物质。