Share on Facebook Share on Twitter Summary: Soil is one of the biggest carbon reservoirs on the planet and the very basis of our existence. We have already lost almost half of the planet’s topsoil (outermost or surface-level soil) in the last 150 years[2]. Livestock farming is responsible for more than half (55%) of global soil erosion[3]. As the world’s population grows, we need to produce more food and soil erosion affects the world’s food production. Soil Erosion Facts Human life depends on the soil’s generosity and soil degradation or erosion poses a direct threat to food security. Apart from supporting food requirements, it is also essential for the following things.

Due to the enormous scale of soil erosion, more than half of the world’s total agricultural land is considered degraded and nearly 2 billion hectares of land (an area twice the size of China) is severely degraded, sometimes irreversibly[5]. To put the numbers into perspective, it takes around 200-400 years to regain 1cm of soil and almost 3000 years to make the same soil fertile[6]. Every year, approximately 24 billion tonnes of fertile soil is lost, which costs the global economy anything between $6.3 and 10.6 trillion dollars [1,4]. Hence soil is considered a non-renewable source. To highlight the urgency of the situation and importance of soil preservation, the UN has declared 5th December as World Soil’s day. Advertisement Soil as Carbon Reservoirs Soil is one of the largest carbon reservoirs on the planet. i.e. Soil holds more carbon dioxide than the living vegetation and atmosphere combined. The infographic from the United Nations perfectly summarizes the soil carbon cycle[4]. Sources: Soils-2015, FAO The below graph highlights the planet’s carbon sinks and the amount of carbon they hold expressed in Gigatonnes carbon (GTC). Source: Nasa Earth Observatory [7] Hence, even relatively small changes in carbon stored in the soil could make a significant impact on the global carbon balance. It is estimated that soil erosion caused by land-use changes along with other agricultural-related emissions are responsible for 24% of global warming-related causes [8]. Advertisement Causes

Share on Facebook Share on Twitter Causes of Soil Erosion Although there are many reasons for soil erosion, we’ll be only focussing on the erosion caused due to livestock farming and deforestation, equivalent to 55% of total erosion[3]. Since 80% of the agricultural land on the planet is used to produce crops for animal feed or for grazing animals, meat and dairy production contribute significantly to soil erosion and associated problems particularly in 2 related ways[1]. Livestock Farming Livestock farming on agricultural as well as forest land is the single largest driver of soil erosion, contributing an estimated 55% of global erosion losses[1]. Soil is loosened by the livestock hoof as well as grazing impacts on pastures and hence it becomes more prone to erosion by wind or rainfall. Also, livestock can overgraze vegetation, disrupting its role of trapping and stabilizing soil and aggravating erosion and pollution[3]. Furthermore, farmers have to maintain field productivity by using fertilizers, pesticides that harm the quality of the soil in the long run and further leading to land and nutrient degradation. Advertisement Land Use Changes Increased demand for agricultural products has incentivised farmers and organizations to convert natural habitats like forests, grasslands and rangelands to farmlands and pastures to meet the ever-growing food demand. Millions of hectares of land have been converted to pastures to grow crops, particularly for soy and corn cultivations which are used as livestock feed in industrialised farms [1,3]. Amazon’s rain forest in Latin America is a prime example of such land conversions. Without plant cover, erosion can sweep lands into rivers as the soil loses it’s compaction and is able to hold less water, thus being more prone to wash off and can drain away easily [4]. Advertisement Facts Consequences