About humus

Humus” comes from the Latin word for “earth” or “soil”. One of the more specific definitions offered is: “The well decomposed, more or less stable part of the organic matter in mineral soils”¹. Other definitions add that humus “makes the soil more fertile”². Scientific studies note that a higher proportion of organic matter in mineral soil has beneficial effects on the fertility of the whole “soil-mix”. For those who are not interested in the specifics, “humus” could be understood as “healthy and fertile soil”. For rihumi the various definitions are all fine as long as you know that we mean the natural stuff that is required to grow plants well.

This stuff, land, soil, earth, dirt, humus or whatever else you want to call it, is endangered by human activities in many different ways. During the last couple of decennia 24% of the global land area has been degrading (Bai et al., 2008). On a global level, about 1.96 billion hectares are affected by “man-made” soil degradation (Oldeman, 2000). As Pimental (2006, p.123) nicely summarised: “Currently, about 80% of the world’s agricultural land suffers moderate to severe erosion, while 10% experiences slight erosion (Pimentel, 1993; Lal, 1994; Speth, 1994). Worldwide, erosion on cropland averages about 30 t/ha-yr and ranges from 0.5 to 400 t/ha-yr (Pimentel et al., 1995). As a result of soil erosion, during the last 40 years about 30% of the world’s arable land has become unproductive and, much of that has been abandoned for agricultural use (Kendall and Pimentel, 1994; WRI, 1994). The nearly 1.5 billion ha of world arable land now under cultivation for crop production are almost equal in area to the amount of arable land (2 billion ha) that has been abandoned by humans since farming began (Lal, 1990, 1994).”

It is time to start giving humus the appropriate attention. Humus is a human right!

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¹ Source: https://www.soils.org/publications/soils-glossary

² Oxford Advanced Learner's Dictionary, 5th edition)

Bai ZG, Dent DL, Olsson L and Schaepman ME 2008. Global assessment of land degradation and improvement. 1. Identification by remote sensing. Report 2008/01, ISRIC – World Soil Information, Wageningen

Oldeman, L.R., 2000: Impact of soil degradation: A global scenario, International Conference on Managing Natural Resources for Sustainable Agricultural Production in the 21st Century, New Delhi, 14-18 February, 2000.

Pimentel, David 2006, Soil erosion: a food and environmental threat. Environment, Development and Sustainability (2006) 8: 119–137