Political debates on global challenges such as achieving food security and combating climate change often fail to consider one of the most vital natural resources of all: soils. This is not a surprise – the multiple beneficial functions of soil are not readily apparent at first glance. Despite the enormous losses involved, soil degradation often occurs so slowly that it takes more than a single human lifetime for its effects to become visible. In land used for agricultural purposes, it takes about 500 years for a 2.5cm layer of fertile topsoil to form.[1]

Soils are essential to the production of over 90% of the world’s food. A lack of fertile soils would therefore place global food security in jeopardy. Thus, managing soils in a sustainable way is essential in the fight against hunger. This is particularly true with regard to the poorest people in the world, as their survival often hinges on the soils that are most severely degraded.

In addition, soils store over 4,000 billion tonnes of carbon.[2] If soils are managed responsibly, they can act as carbon sinks and help to combat climate change. In comparison, forests store 360 billion tonnes of carbon in wood biomass, while the atmosphere contains over 800 billion tonnes of carbon as carbon dioxide. Unsustainable land and soil management practices can cause the release of carbon dioxide back into the atmosphere, and soils may turn from net carbon sinks into net carbon sources. Given the amount of carbon that soils contain, this flux could dramatically accelerate climate change.[3][4][5]

Arable land is limited to just 12% of the Earth’s surface.[6] Developing new land that has agricultural potential for feeding the world’s growing population involves enormous financial and environmental costs, and therefore will only be possible to a limited extent. More than two thirds of the potentially usable land either has soils of insufficient quality or is located on slopes that make it too difficult to farm. Much of the remaining land is covered by forests.

The amount of arable land available per capita is constantly decreasing, from 0.5 hectares in 1960 to 0.22 hectares today. Additionally, about a quarter of the world’s land surface is already degraded and degradation processes such as erosion, sealing of soil surfaces and desertification are on the rise. Estimates indicate that erosion alone is to blame for the loss of more than 24 billion tons of soil each year.[7][8] Although land and soil degradation is frequently associated with desertification in arid regions, it is a global phenomenon.

The limited supply of arable land has dramatically increased foreign direct investments in land in certain developing countries. During the period 2001-2010 developing countries leased or sold a total of 83 million hectares of land to foreign investors.[9] This often jeopardises the land rights of the local population and exacerbates hunger and poverty.

Women are particularly affected by unequal distribution of land and soils. They produce over 50% of food worldwide, while in developing countries, the share is even higher – between 60 and 80%. Despite this, women own only 2% of all agricultural land. It is estimated that women could increase the yields on their farms by 20 to 30% if they had the same access to productive resources as men.[10]

Luckily, solutions to these global problems already exist. It is widely accepted that securing land-use and land-access rights creates incentives for investing in protecting soils and water, which can have positive effects on sustainable production, poverty reduction and economic growth.

Furthermore, agricultural methods that enrich the soil with humus (through mulching, agroforestry, catch crops, etc.) and limited tillage increase the soil’s capacity for retaining water and nutrients, and encourage soil life. Compared to soils that are humus-poor, these humus-rich soils are better at coping with the effects of climate change, such as arid periods, and are less susceptible to erosion.

In 2011, FAO and a group of partners have launched the Global Soil Partnership (GSP) to improve global governance of the world’s soil resources in order to guarantee healthy, productive soils for a food secure world — and to work together to sustain other essential ecosystem services on which our livelihoods and societies depend.

In the framework of the Global Soil Partnership, the Global Soil Week will take place for the first time in Berlin from 18-22 November 2012. It is hosted by the Institute for Advanced Sustainability Studies (IASS) Global Soil Forum and was organized in collaboration with its partners – the Food and Agriculture Organization of the UN (FAO), UN Environment Programme (UNEP), the UN Convention to Combat Desertification (UNCCD), the European Commission, the German Federal Environment Agency, the Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) and the German Federal Ministry for Economic Cooperation and Development. The first Global Soil Week will provide a platform to initiate follow-up actions on land and soil-related decisions made at the UN Conference on Sustainable Development (UNCSD, or Rio+20).

The IASS’s Global Soil Forum addresses global soil-related concerns by carrying out interdisciplinary research into soil-related sustainability issues. It also takes a transdisciplinary approach to champion a balanced transfer of knowledge between researchers, decision-makers and representatives of civil-society organisations globally.

Five months after Rio +20, where the international community agreed on a process towards a set of Sustainable Development Goals (SDGs), and less than two weeks before the new round of negotiations at the 18th session of the Conference of the Parties (COP 18) to the UN Framework Convention on Climate Change (UNFCCC) in Doha, the first Global Soil Week will bring together stakeholders from around the world to develop future plans of action for the sustainable management and governance of soils.

For more information visit the Global Soil Week’s website and follow the coverage of the event by the IISD Reporting Services at: http://enb.iisd.org/soil/gsw1/ In addition, you can join the live stream (at http://www.globalsoilweek.org/) on Monday, 19 November, starting at 11:00 hours GMT+1 and on Wednesday, 21 November, starting at 15:00 hours GMT+1. You will also be able to join the discussions through Twitter. Follow us at @GlobalSoilWeek.

This article was authored by Alexander Müller – Assistant Director-General, Natural Resources Management and Environment Department, FAO, and Jes Weigelt, Project Leader, Global Soil Forum, Institute for Advanced Sustainability Studies (IASS) Potsdam.

[1] Pimentel et al. (2010): Will limited land, water and energy control human population numbers in the future? Hum Ecol (2010) 38.
[2] Tarnocai C, Canadell JG, Schuur EAG, Kuhry P, Mazhitova G, Zimov S (2009): Soil organic carbon pools in the northern circumpolar permafrost region. Global Biogeochem Cycles, 23, GB2023, doi:10.1029/2008GB003327
[3] Yu Z (2011) Holocene carbon flux historiesof the world’s peatlands: global carbon-cycle implications. The Holocene 21:761-774
[4] Eswaran H, Reich PF, Kimble JM (2000): Global carbon stocks. In: Lal R, Kimble JM, Eswaran H, Stewart BA (eds): Global climate change and pedogenic carbonates. CRC Press, Boca Raton, FL, pp. 15-25
[5] Jobbágy EG, Jackson RB (2000): The vertical distribution of soil organic carbon and its relation to climate and vegetation. Ecol Appl 10:423-436.
[6] G. Fischer, E. Hizsnyik, S. Prieler & D. Wiberg (2010) Scarcity and abundance of land resources: competing uses and the shrinking land resource base. SOLAW Background Thematic Report – TR02. FAO, Rome.
[7] John N. Quinton, Gerard Govers, Kristof Van Oost, Richard D. Bardgett (2010) The impact of agricultural soil erosion on biogeochemical cycling. Nature Geosci 3:311-313.
[8] Bai ZG, Dent DL, Olsson L, Schaepman ME (2008): Proxy global assessment of land degradation. Soil Use Manage 24:223-234.
[9] Anseeuw, W. et al. (2012): Transnational Land Deals for Agriculture in the Global South. Analytical Report based on the Land Matrix Database, http://landportal.info/landmatrix/media/img/analytical-report.pdf
[10] UN (2012): Resilient People, Resilient Planet: a Future Worth Choosing.