Though its fundamental to life, but human pressures on soil resources are reaching critical.

Human security has and will continue to rely on Earth’s diverse and healthy soil resources. Yet we have now exploited the planet’s most productive soils. Soil erosion greatly exceeds rates of production in many agricultural regions. Nitrogen produced by fossil fuel and geological reservoirs of other fertilizers are headed toward possible scarcity, increased cost, and/or geopolitical conflict.

The connections between soils and societal issues – such as food security, sustainability, climate change, carbon sequestration, greenhouse gas emissions, and degradation through erosion and loss of organic matter and nutrients – are central to the recently developed concept of soil security (Mc Bratney, Field and Koch, 2014).

Changes in the balance of important soil processes caused by human disturbance.

Humans altered the ecosystems they encountered as they began their spread across the globe. However, the most momentous development in human landscape change occurred with the invention and adoption of modern agriculture (1). Most agricultural practices involve the cutting of trees for converting to open landscape, removal of the natural flora, the simplification of biodiversity to favor monocultures, and other physical disruption.

The large-scale use of pesticides has increased worldwide to approximately two million tonnes per year (herbicides 47.5 percent, insecticides 29.5 percent, fungicides 17.5 percent, other 5.5 percent by De et al. (2014)), may have direct or indirect effects on soil biodiversity. Effects are dependent on a variety of factors including the chemical composition, the rate applied, the buffering capacity of the soil, the soil organisms in question, and the time-scale. Since the Industrial Revolution, expanding populations have relied on the exploitation of more and more soil for a corresponding growth in food production. The late 20th and early 21st centuries have been, for industrialized

Careful soil management is one essential element of sustainable agriculture and also provides a valuable lever for climate regulation and a pathway for safeguarding ecosystem services and biodiversity.

countries, an unprecedented era of increasingly low food prices. There are numerous factors that may reverse this trend— such as increased global demand; climate change; and competition for soil by nonagricultural uses, such as biofuels or urbanization. Abundant energy has been the key driving force behind our ability to maintain food production apace with an expanding population that is estimated to reach 11 billion by 2100.

Sustainable soil management

Sustainability: development that meets the needs of the present without compromising the ability of future generations to meet their own needs. The services provided by soils are primarily determined by the three core soil properties (texture, mineralogy, and organic matter), which together form the natural capital of soils (Palm et al. 2007). Soil texture and mineralogy are inherent properties of soil that are initially inherited from the parent materials and which change only very slowly over time. In a natural state, soil organic matter (SOM) reaches equilibrium with the environment in which the soil forms, but SOM responds quickly to human-induced changes. Management of SOM is central to sustainable soil management because of its rapid response to change and our ability to manipulate it.

Careful soil management is one essential element of sustainable agriculture and also provides a valuable lever for climate regulation and a pathway for safeguarding ecosystem services and biodiversity.

The concept of sustainable soil management is central to pillar one of the Global Soil Partnership(2): “Promote sustainable management of soil resources for soil protection, conservation, and sustainable production”. Soil management is sustainable if the supporting, provisioning, regulating and cultural services provided by soil are maintained or enhanced without significantly impairing either the soil functions that enable those services or biodiversity.

References:

1. J. Diamond, Evolution, consequences and future of plant and animal domestication. Nature 418, 700–707 (2002). doi: 10.1038/nature01019; pmid: 12167878

2. The Global Soil Partnership was initiated by FAO and the EU in 2011.For a description of the five pillars, see a full description of the Partnership, in www.fao.org/globalsoilpartnership).