The equilibrium between, and amicable coexistence of, organisms and their environment. Changes in air temperature, precipitation, and carbon dioxide levels, plus lesser ecological changes, may alter the ecological balance between communities: ‘slight increases in individual mortality of one community, coupled with increased success rates of another, could eventually cause changes in the geographical distribution of forests, grasslands, and deserts’ (Masek (2001) J. Biogeog. 28, 8). See Ding et al. (1998) PPG 22 on the concept of ecological balance and the definition of desertification.