PASTURES FOR PROSPERITY .4. MANAGING RESOURCES - MOVING FROM SUSTAINABLE-YIELD TO SUSTAINABILITY IN TROPICAL RANGELANDS

Emphasis in management and research for tropical grasslands has focuss ed on increasing productivity via the addition of new plants, animals or energy to native systems. The criterion for success was economic pe rformance. However, public expectations and a more thorough understand ing of ecosystem dynamics, have redefined the goals of land management . In this paper, we identify temporal and spatial variability as the p rimary constraints to sustainable land management in tropical grasslan ds and provide experimental evidence to suggest that an enhanced under standing of key ecological processes is central to achieving sustainab ility.