Soils and sustainable agriculture. A review

Enhancing food production and supporting civil/engineering structures have been the principal foci of soil science research during most of the 19th and the first seven or eight decades of the 20th century. Demands on soil resources during the 21st century and beyond include: (i) increasing agronomic production to meet the food needs of additional 3.5 billion people that will reside in developing countries along with likely shift in food habits from plant-based to animal-based diet, (ii) producing ligno-cellulosic biomass through establishment of energy plantations on agriculturally surplus/marginal soils or other specifically identified lands, (iii) converting degraded/desertified soils to restorative land use for enhancing biodiversity and improving the environment, (iv) sequestering carbon in terrestrial (soil and trees) and aquatic ecosystems to off-set industrial emissions and stabilize the atmospheric abundance of CO2 and other greenhouse gases, (v) developing farming/cropping systems which improve water use efficiency and minimize risks of water pollution, contamination and eutrophication, and (vi) creating reserves for species preservation, recreation and enhancing aesthetic value of soil resources. Realization of these multifarious soil functions necessitate establishment of inter-disciplinary approach with close linkages between soil scientists and chemists, physicists, geologists, hydrologists, climatologists, biologists, system engineers (nano technologists), computer scientists and information technologists, economists, social scientists and molecular geneticists dealing with human, animal and microbial processes. While advancing the study of basic principles and processes, soil scientists must also reach out to other disciplines to address the global issues of the 21st century and beyond.