Impacts of extensive grazing and abandonment on grassland soils and productivity

• Published in: Agriculture, ecosystems & environment ecosystems & environment, 2010-12, Vol.139 (4), p.476-482
• Main Authors: Marriott, C.A., Fisher, J.M., Hood, K., Pakeman, R.J.
• Format: Article
• Language: English
• Subjects: abandoned land; Accumulation; Agricultural production; Agronomy. Soil science and plant productions; Animal productions; Biodiversity; Biological and medical sciences; botanical composition; Carbon; Ecosystem services; Extensification; Fundamental and applied biological sciences. Psychology; General agroecology; General agroecology. Agricultural and farming systems. Agricultural development. Rural area planning. Landscaping; General agronomy. Plant production; Generalities. Agricultural and farming systems. Agricultural development; Grassland; Grazing; grazing management; intensive livestock farming; land management; long term experiments; nitrogen; Nutrients; nutritive value; pastures; plant communities; Productivity; Reduction; Soil carbon; soil fertility; soil organic carbon; soil pH; soil water content; Soils; Terrestrial animal productions; Trade-offs; Tradeoffs; vegetation; Vertebrates
• ISSN: 0167-8809; 1873-2305
• DOI: 10.1016/j.agee.2010.09.005

▶ At the dry site there is a trade-off between soil carbon and productivity. ▶ At the wet site, intensive grazing promotes soil carbon. ▶ Changes in major nutrients have little impact on productivity. Two long-term (16 year) experiments on intensively managed pastures compared extensive grazing, abandonment and continued intensive grazing and were assessed for impacts on soil parameters, plant nutrient content and ecological indicator values. There was a reduction in soil carbon and nitrogen in the abandoned treatment compared to the intensively managed treatment at the wetter site. At the drier site, extensive grazing resulted in a build up of soil carbon. There was a build up of dead organic matter and a reduction in the nutritive value of the vegetation as grazing was reduced. Indicator values confirmed the reduced soil nutrients and a fall in site pH. There was also a rise in the dominance of plants preferring moist conditions, especially at the wetter site. As biodiversity gains are small, the management of these systems could be seen as a trade-off between managing for production and for soil organic carbon. At the drier site this trade-off is apparent, whereas at the wetter site managing for production also maximises soil carbon content.