What is Soil Conservation?
Soil conservation is defined as the act of preserving the loss of soil nutrients or infertility from erosion which is usually caused by salinization, organic carbon loss, acidification, over usage of soil or by other chemical soil contamination. Traditional agricultural practices are based on ploughing and tilling of land in preparation of seedbed. These practices have been shown to be highly destructive of the soil with about 24% of global agricultural land being degraded; however, soil-conservation farming encouragesno-till farming, green manures and other soil-enhancing practices.
It is no longer a surprise that soil erosion has rendered millions of acres of land unusable and highly unproductive in many parts of the world. If the world is to meet up with adequate provision of food for the daily increase in the population and to avert famine and diseases, measures must be taken to check the ravages of excessive erosion on agricultural land.
Acidification, organic carbon loss, salinization, compaction and over usage all threaten the proper functioning of soils to a high level in different parts of the world. One of the most important and maybe the most threatening is increase erosion due to agricultural disturbance. When soils are continually used for farming, their natural vegetation cover is removed and they are often disturbed by tillage. The result is that, under conventional tillage, erosion rates by running water on arable land are, on a high increase compered to those seen under natural vegetation. This acceleration creates a major imbalance as soil nutrients are removed by soil erosion. Eroded soil is in many cases, truly lost and cannot be restored although not in cases, which explains why land prices in areas heavily affected by erosion may remain lower than expected, even when excessive erosion has been halted for several decades.
The terrestrial land surface provides critical services to humans and this is largely possible because soils are present and are constantly used. Humans use about 37% of the total Earths land mass as arable farmland; however, part of this is land is used as grazing sites, construction sites. On the same land plants grow on it which are either directly used as food or indirectly as feed, fuel or fibre and still used by humans for nutrition and a large range of economic activities.
Agricultural lands, especially areas used as arable land, are the most used areas; this is because they have soils that make them suitable for agricultural purposes. But it is not only the soils on agricultural land that provide humans with essential needs but also on non-agricultural land, the soils still provide space for plants roots to grow, the soils store a required amount of water necessary for their growth and provide nutrients in ways that plants can have access to. On agricultural and non- agricultural lands, soils are therefore a vital part of humans global support system, as in the case of the atmosphere and the oceans. An Earth without soils would be fundamentally different from the Earth we know, as in all likelihood, it wont be able to support human life as we know it.
Having seen all of these, there is need for soil conservation in order to prevent the soil from further loss of nutrients and organic matters. To protect soils from the different threats posed to them by modern agriculture and other human activities. Yet, as is the case with many other natural resources, soils are under intensive pressure.
There are certain ways in which we can implement soil conservation, this technology has emerged over the last decades, hence we now have the methods to effectively reduce erosion rates on agricultural lands. The implementation of soil conservation measures depends on a multitude of factors but it is also clear that rapid change in agricultural systems only takes place when a clear economic incentive is available for the farmers. Conservation measures are often more or less cost-neutral, which explains why they are often less generally practiced than expected. This needs to be accounted for when developing a strategy on how we may achieve effective soil conservation in the Global level, where agriculture will fundamentally change in the next century
Soil Conservation Measures
- By terracing hillsides to prevent soil erosion- Terrace farming uses the relief of the land to allow water flow through a serries of terraces. The teraces form a serries of steps each at a higher level than the previous. This method helps to reduce the velocity of water running down the hill slopes. This method is commonly practiced in parts of Java, Japan, Monsoon Asia etc.
- Through contour ploughing– whereby the furrows in which the crops are planted create a narrow and banked up terrace round hillsides.
- By strip-cropping– this is when grasses are planted in stripes, soil binding leguminous crops and yearly cereals at right angles to the prevailing wind.
- Planting of cover crops– cover crops such as legumes, melons, potatoes, cowpeas etc. to cover the soil and to reduce surface run-off, helps keep the soilhealthy, hence contributing to better harvests.
- By afforesting hill-slopes– trees should be planted in strips across the erosion-prone lands to reduce the velocity of water, trap silt, and to prevent further erosion from occurring.
- Conversion of cropland into pasture– land use can be changed into a different use, especially in certain areas experiencing severe soil erosion. For instance, if the land was initially used for grazing, it should be allowed to revert to native vegetation to allow organic matter to build up. In other cases, it may be necessary to stop any further cultivation and keep the areas only for a longer period to retain back its natural state.
- Replacing fallow crops with suitable crop rotation– crop rotation like sequences intercropping or mixed cropping should be encouraged.
- By dividing up large field into smaller ones surrounded by hedges and walls that acts as wind breakers
- By limiting the number of animals on a farm to the actual holding capacity of the pasture.
Importance of Soil Conservation
- Our soil needs to be conserved for plant growth; this will help the plants to create more nutrients like starch, protein etc. that human body need for energy and metabolism.
- So many microbes prefer to live in healthy soil; these microbes produce amino acids, which plants convert to protein. If the soil is not conserved, these precious microbes are lost from the soil through heavy and continuous running water.
- Living organisms such as bacteria, fungi and microbes, which live in healthy soil, form a natural defense against pests and diseases, while infertile and erosion prone soils have fewer microbes thereby, exposing plants to pest and disease.
- Rich soils are healthy soil which contributes to the healthiness of the environment and other living creatures around it, a healthy soil promotes healthy plant growth and also contribute to the increase yield of plants.
- Nutrient-rich soil has a strong and stable structure. When the soil is not conserved, it loses the structure causing dust clouds to form, increasing erosion and airs and land pollution.
- Countries with nutrient-rich soils are known for increased food yield, they dont experience food scarcity. Year in year out, their food produce are in high demand, hence the food produce provide constant revenue and foreign exchange to the country.