ABSTRACT
Principal global issues of the 21st century are: (1) population of 6.5 billion and increasing at the rate of 1.14% yr-1, (2) per capita arable land area of 0.22 ha and decreasing to < 0.07 ha for 30 countries by 2025, (3) soil degradation of 2 billion ha (Bha) and increasing at the rate of 5-10 million hectares (Mha) yr-1, (4) renewable fresh water supply of < 1000 m3 for 30 countries and increasing to 58 countries by 2050, (5) atmospheric C 0 2 concentration of 378 ppm and increasing at 0.46% yr-1, (6) energy use of 435 quads (1015 BTU) yr-1 and increasing at the rate of 2.2% yr-1, and (7) per capita grain consumption of 300 Kg yr-1 and decreasing. These global issues cut across national/political borders, because people and nature are inextricably linked, irrespective of political boundaries. Therefore, addressing these issues warrants a coherent and coordinated effort. Further, soil degradation is a common thread that transcends all seven issues. Therefore, an objective assessment of the processes, causes and factors affecting soil degradation may be necessary to identify viable technological interventions of addressing these issues.
