The Effects of Grazing on Above Ground Plant Biomass, Microbial Respiration, Net Ammonification, and Select Physical Properties of Coastal Prairie Soils.

A paired-plot analysis was conducted to quantify the effects that cattle grazing has on select soil physical and biological properties. Utilization cages measuring 1 m² were placed on several grazed areas throughout Redwood Creek Ranch—20 miles east of Blue Lake, CA—during the summer of 2012. They were revisited two years later on February 15, 2015 and March 29, 2015. Seven coastal prairie grassland soils were sampled from inside and directly adjacent to utilization cages to better understand the influence that cattle grazing imparts on aboveground plant biomass, bulk density, percent soil organic matter (SOM), microbial respiration, and net ammonification. Paired plot T-tests reported significantly (p < 0.05) more above ground plant biomass inside of cages, and higher bulk density measurements outside. No other significant findings were reported between the two management practices (no grazing and continuous grazing). 

Key words: Grazing, rangeland, soil microbial biomass, nitrogen mineralization, plant biomass, bulk density, soil organic matter.