Soil Organic Matter Recovery in Semiarid Grasslands: Implications for the Conservation Reserve Program

摘要: Although the effects of cultivation on soil organic matter and nutrient supply capacity are well understood, relatively little work has been done long-term recovery soils from cultivation. We sampled 12 locations within Pawnee National Grasslands northeastern Colorado, each having native fields that were his- torically cultivated but abandoned 50 yr ago. also had for at least 5 these locations. Our results demonstrated matter, silt content, microbial biomass, po- tentially mineralizable N, potentially respirable C significantly lower than fields. Both contents Abandoned fields, however, not different with respect to or C. In addition, we found characteristic small-scale heterogeneity shortgrass steppe associated individuals dom- inant plant, Bouteloua gracilis, recovered Soil beneath plant canopies an average 200 g/m2 more between-plant suggest is adequate time active availability, total pools a much slower process. Plant population dynamics may play important role in ecosystems disturbance, such establishment perennial grasses determines rate recovery.