Soil nitrate and ammonium: Effect of Fire Frequency on Grassland Vegetation and Soils

The purpose of this experiment, begun in 1983 by Johannes Knops, is to determine what effect different fire frequencies have on grassland vegetation. This experiment is being conducted in field B. There are 4 different burn treatments: 1. plots burned every year 2. plots burned every other year 3. controls which are not burned 4. plots burned every fourth year There are 6 replicates of each treatment which were randomly assigned to the 24 plots. Plots are 8 by 8 meters and are placed in a 3 by 8 grid with 2 meter walkways. Plots are marked with colored rebar at each corner.约翰内斯·克诺普斯（Johannes Knops）于1983年启动本实验，旨在探明不同火烧频率对草原植被的影响。本实验于B样地开展，共设置4种火烧处理方案： 1. 每年火烧样地 2. 隔年火烧样地 3. 未火烧对照样地 4. 每四年火烧样地 每种处理设置6个重复，随机分配至24个样地中。单块样地尺寸为8米×8米，以3行8列的网格排布，样地间设有2米宽的步道。样地四角均采用彩色钢筋（rebar）进行标记。