Saving and Rebuilding Our Soil
Saving the environment requires more than simply planting trees and leading a greener life, although that definitely helps. It also involves attempting to return the environment to its original state. While oceans, the atmosphere and rainforests receive a lot of attention, soil is rarely mentioned. In fact, improving soil quality is one of the most important factors in saving our environment since it provides us with important food and vegetation.
All over the world the disappearance of topsoil has begun to worry many farmers and scientists. The US has the highest loss percentage, with some areas losing 75 percent of their topsoil with other countries seeing similar results. The major cause of this land degradation is from overgrazing, deforestation and agricultural use. Patterns of soil loss differ in each region with agriculture accounting for 66 percent in North America while Africa has problems with overgrazing. Still almost all areas around the world have soil degradation that’s either of some or serious concern. While there are numerous layers of soil, topsoil contains almost all of the nutrients important to plants and takes nearly 100 years to create one millimeter of topsoil. Plants absorb these nutrients from the soil and when the soil begins containing less nutrients, the plants become weaker and more vulnerable to pests and disease, leading to increased usage of chemical fertilizers, pesticides and herbicides, all which are absorbed into the vegetables and fruits put on our tables [Source: The Guardian]. These harsh chemicals and farming techniques leads to a higher rate of soil erosion. Without topsoil, there is not enough nutrients in the layer below to sustain plant life. Without plant life, the soil becomes more susceptible to wind and water erosion and either form large sediment deposits in rivers or dust bowls. Around the world topsoil is eroding faster than it can be replaced, and the US alone spends $125 billion to combat topsoil loss [Source: University of Michigan].
Despite these numbers, many governments around the world have realized the importance of conserving what is left of our topsoil. In 1985 the US government contracted 14 million hectares of land under the Conservation Reserve Program (CRP) that paid farmers to convert highly erodible cropland to vegetative cover including trees, grasslands and native wildplants. From 1982 to 1997, the US was able to reduce topsoil erosion from 3.1 billion tons to 1.7 billion tons [Source: Earth Policy]. States like Oregon are in the forefront of the CRP program and have covered 550,000 acres of fragile topsoil, a value of nearly $27 million if actually allowed to be cropland. Oregon plans on adding more cropland to the CRP in 2011. Nationally, there is 31.2 million acres of land dedicated to the CRP with a cap of 32 million acres [Source: Natural Resource Report]. Many other countries are following the US lead and are beginning to plant many more trees in order to prevent desert encroachment. The Moroccan government in 2005 canceled farmers’ debts and encouraged the replacement of more fragile cereal crops to olive trees and orchards. Countries in Africa have created the Green Wall Sahara Initiative that calls for planting 300 million trees along 3 million hectares of land in Africa. The initiative has expanded to also include improved land management practices and crop rotation. China as well plans to plant nearly 4,480 km (2,800 miles) of land near the Gobi Desert to prevent further desertification. The Mongolian government is also focusing on planting desert shrubs to stabilize various dunes within the Gobi Desert. The government has become so committed to preventing further soil erosion that sheep and goats have been banned completely and in China, the government is pushing for farmers to reduce their sheep and goat herds by 30 percent [Source: Earth Policy] .
For the land that is still being used for crops, many farmers are beginning to use different methods of farming in order to save the soil. One of the most common method is conservation tilling, which includes no till and minimum tillage. Conventional tilling of soil not only releases stored carbon – roughly 78 billion metric tons of carbon has been released due to tilling [Source: Ohio State Research] – it also leave less than 15 percent crop residue cover less than 500 pounds per acre (560 kg/ha) of small grain residue. This turning of the soil leads to higher degradation of important organic materials in the soil and also allows for faster water travel through soil, which leads to faster erosion. Conservation tilling techniques require farmers to leave at least 30 percent crop residue, which allows for water to travel slower through the soil, resulting in less erosion. These methods also help reduce fuel cost on farmers and could also potentially earn farmers more money than through conventional techniques. In the US there is currently over 27 million hectares of farm land using no-till with five other countries following suit:
- Brazil – 26 million hectares
- Argentina – 20 million hectares
- Canada – 13 million hectares
- Australia – 12 million hectars [Source: Earth Policy].
Unfortunately, the no-tilling technique could potentially lead to higher usages of herbicides as traditional tilling technique removes many invasive weed species.
The importance of saving our topsoil has been a worry for farmers for nearly three decades. Still, there is little public awareness concerning government programs aimed at conserving topsoil. Not only that, but there are still many farms around the world that do not have proper information on how to conserve soil and still make profits. Not only does the government need to push for these reforms, farmers also need to take the initiative and begin better farming methods.