INTRODUCTION Soil degradation is a most serious environmental problem in many countries. One of the most important driving forces of soil degradation is human activities. Human activities often influence the natural processes in soil. According to (Doran et al., 1998; Cavelier et al., 1999; Chew, 2001; Liu et al., 2002; Johnson and Lewis, 2007; Seeger and Ries, 2008) defined deforestation as a perceptible aspect of human activities in environment. This change has many effects that can appear through the reduction of chemical and physical qualities of the soil resources.
SOIL EROSION I. INTRODUCTION Soil erosion is one of the most devastating environmental disasters which always happen all over the globe and it is caused by unavoidable natural phenomenon factors such as climatic factor, physical characteristics of soil and cover and management factor and the solution on how to reduce soil erosion which are managing soil surfaces, improving organic matter and making grasses waterway. II. BODY Factor of Soil Erosion A. One of the reasons that contribute to this soil erosion problem is climatic factor.
This is because the higher demand for food and fuel causes the removal of protective vegetation from the area, meaning that rain-splash erosion and aeolian erosion can occur. The chance of desertification increases when an area is experiencing drought conditions. This is because the soil is already stressed by the processes of overcropping and overgrazing, and so a drought dries out the soil completely and causes it to become useless and desertified. In Sahelian countries such as Chad and Niger, cash crops (Crops only sold for their monetary value) such as cotton and cashew nuts are grown in massive plantations as part of economic reforms known as structural adhustment programmes. This is because the owners of these farms receive debt relief for growing this crop.
Not only is it a very serious problem, it has also become widely spread that it demands our immediate action. Soil erosion is caused and affected by several factors; however, it can be minimized by several easy actions which one can implement daily. Introduction: Soil
However it is sometime considered that the soil health is depends on biological activities held in the soil. There are few controversies about role of soil in plant growth and yield, as few belifs on its direct effect on plant growth and yield, while rest consider that it mere provide physical support and the growth and yield are the result of non-soil components, such as fertilizer and pesticide. Soil organisms contributes significantly in soil health through various ways such as, humus formation, decomposing dead plant and animal residues, enrichment of soil organic matter, etc. They produces carbon dioxide in soil to be dissolved in water and further converted in carbolic acid, which breakdowns insoluble rock minerals (Edwards et al. nd.).
Increasing population, intense land cultivation, uncontrolled grazing, and deforestation often lead to, or exacerbate, soil erosion (Tadesse, 2001; Bewket, 2002). These factors undermine agricultural productivity and frustrate economic development efforts, especially in developing countries where there is heavy land dependence (Shiferaw & Holden, 2000; Feoli et al., 2013) in low external-input farming systems (e.g., the Ethiopian
To add salt to the wound, deforestation also results in soil degradation and soil erosion. Roots of trees acts as anchor to the soil. Therefore, without trees, the soil is free to wash or blow away, which can lead to problems in growth of vegetation. Cash crops like coffee, soy and palm oil are usually planted after a clear cutting. Planting these types of trees can cause further soil erosion because their roots cannot hold onto the soil.
INTRODUCTION What objects can prevent soil erosion the best? Erosion is the process in which the Earth’s surface gets worn down by the forces of nature, which can be a good or a bad thing. A beneficial result of erosion is the movement of nutrient rich soil to new areas. New plants and trees can grow in those areas, aiding people as well as animals. Erosion can form riverbanks, caves, wetlands, and other habitats for animals to live in.
When topsoil becomes eroded during heavy rains, it washes away nutrient rich soil needed by plants for growth. This limits the amount of vegetation on an area which subsequently leads to further erosion of soil and therefore soil degradation. Animals may lose habitats and food sources due to lack of plants to feed on and this will affect the natural species population in these areas (Mack, 2017). When loose sediment is combined with water, natural disasters
Review of Related Literature 2.1 Introduction Soil is an important source of raw materials such as clay, sand, gravel and minerals. It is a non- renewable natural resource with potentially rapid degradation rates and extremely slow reformation and regeneration process(Mwangi,2007). Sand is a cheap and heavy resource consisting of very small pieces of rocks and minerals, a result of weathering that forms beaches and deserts. River sand is extracted from riverbeds and banks; unscientific mining has led to the degradation and ecological imbalance around mining areas(Saviour,2012). Gaddard (2007) realised that decisions on where to mine, how much and how often requires definition of "reference state" and sand budget.