To begin, we define soil as the weathered and fragmented outer layer of the earth’s terrestrial surface. It is formed initially through disintegration, decomposition, and recomposition of mineral material contained in exposed rocks by physical, chemical, and biological processes. The material thus modified is further conditioned by the activity and accumulated residues of numerous microscopic and macroscopic organisms (plants and animals). In a series of processes that may require hundreds or even thousands of years and that is called soil genesis, the loose debris of rock fragments is transmuted into a more or less stable, internally ordered, actively functioning natural body. Ultimately, this culminates in the formation of a characteristic soil profile, which resembles a layer cake. We can visualize the soil profile as a composite living body, in the same way that we think of the human body as a distinct organism, even though in reality it is an ensemble of numerous interdependent and symbiotically coordinated groups of organelles, cells, organs, and colonies of myriad organisms. <...>

“Water, water, every where, — nor any drop to drink” (Samuel Taylor Coleridge, “The Rime of the Ancient Mariner”) aptly sums up the overall picture of the hydrosphere — that part of planet Earth made up of water. The oceans, covering 71% of the surface of the globe, make up 97.25% of the mass of water. Most of the freshwaters, whose volume is estimated to be 39·106 km3, are also not immediately accessible: 29·106 km3 is ice accumulated on mountain glaciers and on the ice caps of the poles; 9.5·106 km3 constitute groundwaters and only about 0.13·106 km3 are surface waters, mainly lakes and rivers. The amount of water held up in the biosphere is estimated to be 0.6·103 km3. The atmospheric moisture amounts to just 13·103 km3 — less than 10−5 of the total amount of water — but this small amount is the one which actuates the hydrologic cycle by virtue of its dynamic nature. <...>

Agricultural productivity growth is vital for economic and food security outcomes which are threatened by climate change. In the present times, changing climate is a burning issue. Climate change may be limited to a specific region or may occur across the earth.