Effects of mowing, spring precipitation, soil nutrients and enzymes on grassland productivity
Reinhart, Kurt; Komatsu, Kim; Vermeire, Lance (2023), Effects of mowing, spring precipitation, soil nutrients and enzymes on grassland productivity, Dryad, Dataset, https://doi.org/10.5061/dryad.wstqjq2qg
Little research has assessed how the timing and intensity of grazing might affect plant biomass, available nutrients, and soil extracellular enzyme activity (EEA), and how climate change might influence these responses. We tested the effect of two spring precipitation variability (rainfed control, -30% of ambient), two mowing intensity (moderate, severe), and two mowing season treatments (June, October) on plant and soil properties. We detected an interactive effect of precipitation, mowing intensity, and mowing season on plant biomass. When plots were mowed at a moderate intensity, water reductions had irregular effects on plant biomass depending on the mowing season. Plant biomass was also 11% greater in plots mowed at moderate than severe intensities. Most soil nutrients were unaffected by treatments, except for calcium. Soil EEA was unaffected by treatments; however, the activity of a phosphorus (P)-acquisition enzyme was ≥4 times greater than the activity of nitrogen (N)- and carbon-acquisition enzymes. A substantial amount (adjusted R2= 0.51) of plot-to-plot variation in plant biomass was explained by three soil properties, especially a N-acquisition enzyme and to a lesser degree by plant available P and soil pH. The grassland had a high degree of natural buffering capacity as most soil properties were resistant to shifts in 6-yr spring precipitation and 5-yr simulated grazing intensity and season. Grassland plant biomass varied by treatments and was seemingly limited by biogeochemical constraints, especially the prevalent need to mobilize P and a secondary need to acquire N as plant biomass increased.
All data collection and analysis methods are described in, "Effects of mowing, spring precipitation, soil nutrients and enzymes on grassland productivity".
USDA appropriated funds*, Award: 5434-21630-003-00D