|Data by Research Category|
Project: Multiple Stressor Experiment II (MSE-II): Effect of multiple stressors (grazing and shrub removal) on decline and recovery of perennial grasses in a black grama-mesquite savanna on sandy soils
The objective of this project is to determine the effect of multiple stressors (grazing and shrub removal) on the decline and recovery of perennial grasses in a black grama-mesquite savanna on sandy soils. The initial savanna state represents an intermediate and possibly stable state between black grama grassland and mesquite shrubland. The experimental manipulations removed about 60% of aboveground herbaceous biomass over 24-36 hour periods in each of four years (from summer 1996-winter 2000). One grazing treatment applied grazing in winter and the other in summer. Including controls (ungrazed and shrubs left intact), this results in 6 treatment combinations. Treatments were applied in a randomized complete block design within 3 replicate blocks resulting in 18 experimental units. Experimental units were 0.5 ha (70 x 70 m) areas that have remained ungrazed by livestock after manipulations were completed in 2000.