Woody-Herbaceous-Livestock Species Interaction

Woody-herbaceous-livestock species interactions have attracted a great deal of research attention due to global land cover changes and increasing livestock production systems around the world. It has been well recognized that many local and regional factors, physical and biological, influence the interaction between woody and herbaceous species. While impacting the dynamics, and tipping the balance between woody and herbaceous species, livestock grazing effects also interact with these factors leading to various ecosystem states and woody/herbaceous ratios. The result is a complex set of multiple interacting factors that are difficult to experimentally control in long-term studies at large spatial scales. Ecological processes and empirical relationships observed in woody-herbaceous-livestock interactions, therefore, have largely been developed based on site-specific, local-scale studies emphasizing limited number of factors, processes, and relationships. Many of the proposed processes and empirical relationships have not been explicitly tested outside of the areas where they were developed. Future studies need to use such site-specific data in quantitative models and simulation-based approaches and test the validity of empirical models that are based on local data and relationships.