Alright buddy, this time we will discuss aboutUnderstanding Erosion and Soil Conservation Methods, let’s just get into the discussion.
DEFINITION OF SOIL EROSION
Soil erosion (soil erosion) is the process of washing away the soil and is a natural phenomenon that is natural and continues as long as there is flow on the surface. The erosion proceeds in balance with the rate of soil formation so that the soil undergoes continuous rejuvenation. Soil erosion turns into a hazard if the process takes place faster than the rate of formation of the soil. Rapid erosion will thin the soil, and eventually can make soil parent material such as bedrock to the soil surface.
This erosion will damage the upstream area that is affected by direct erosion, as well as the downstream area. Erosion material deposited in the downstream area will have a negative impact on buildings or natural bodies of water storage or distribution, causing sagging which results in the capacity of the reservoir or channel decreasing rapidly and damaging land and settlements.
Erosion will cause a decrease in the quality of agricultural land in Indonesia. During the rainy season, where high rainfall is concentrated in certain months, the level of erosivity is very large, so that erosion is the main cause of dry land in the wet tropics. Soil lost due to erosion is a fertile topsoil, so erosion will reduce soil fertility significantly.
On sloping soils, erosion is also a serious problem. Where the slope and the length of the slope are two elements of the slope that affect runoff and erosion. If the speed is doubled, then the soil particles stuck are 32 times. On bare land, it will cause disruption of water flow which will cause damage to infrastructure and road facilities.
UNDERSTANDING CONSERVATION METHODS
Conservation is an effort to keep soil productive or repair soil damaged by erosion. Conservation actions have certain criteria, such as one of the considerations is the erosion limit value that can still be ignored (tolerable soil loss). There are three choices of conservation techniques, namely:
1. Vegetative method
Namely any use of plants/vegetation as soil protection from erosion, inhibition of surface runoff, increasing soil moisture content, as well as improving soil properties, both physical, chemical, and biological. Plants or plant remains function as soil protectors against the impact of raindrops as well as the carrying capacity of surface runoff (runoff), as well as increasing water infiltration into the soil.
One example is vetiver grass, known as vetiver, or usar. That is a plant with grass that is large and has many functions. The use of this plant is called Vetiver System (VS). Which VS is a technology that utilizes live vetiver plants for soil conservation.
VS is very effective for soil conservation and easy to use, conserve water and also stabilize and improve land. Vetiver is also easy to control because it does not produce flowers and seeds that can quickly spread wild like the reeds or grasses found in most wild plants.
The wonder of vetiver as ecological is caused by unique root system. This plant has long fibrous roots that enter vertically into the soil. Even the length of this root reaches 5.2 meters into the ground, so you can imagine how this vetiver grips the ground.
The roots of this vetiver can penetrate a layer of soil up to 15 cm thick which is very hard. On very dense slopes, the tips of the vetiver roots are able to penetrate and become a kind of firm gripping anchor. The way these roots work is like an iron column that goes deep into the soil texture layer. So there is no need to doubt its function to prevent erosion, be it from wind or water.
2. Mechanical Method
Mechanical method is a way of land management by using physical means such as soil or rocks as a means of preventing soil erosion. The goal is to slow the flow of water on the surface, reduce erosion and accommodate and drain surface water flow.
Included in this method is the method of tillage. This tillage serves to create soil conditions that make it easy for plants to grow on it, including making rorak (water drains) and making terraces. The purpose of tillage is to prepare a place for seedlings to grow, create a good root area, remove plant debris and eradicate weeds.
Technical and mechanical erosion control is soil maintenance efforts to reduce the amount of soil that loses its function in agricultural land areas in a certain way. In connection with mechanical soil improvement efforts, the aim is to slow down runoff and accommodate and continue the distribution of surface runoff with non-destructive soil erosion.
Terraces are mechanical soil and water conservation structures designed to shorten the length of the slope and or reduce the slope of the slope by digging and filling the soil across the slope. Making terracing is to change the sloping land surface to be terraced, so this situation will reduce the surface runoff speed because the slope angle is also changed and holds and accommodates it, so more water seeps into the soil through the infiltration process, so the soil becomes fertile.
Broadly speaking, terracing is a condition of slopes made of stairs that can be used on highlands and serves to:
- Increase slope stability
- Facilitate the process of slope conservation
- Extend the water catchment area into the ground
- Shorten the length of the slope and or reduce the angle of the slope
- Reduces surface runoff
- Can be used for landscape
The types of terracing according to the slope, namely:
Flat terraces are made on land with a slope of less than 3% (flat) with the aim of improving water drainage and soil wetting. Flat terraces are made by digging the soil according to the height line and the excavated soil is then backfilled to the outer edge, so that water can be held and collected. The bunds formed are planted with grass.
The credit terrace is made on sloping soil with a slope of 3 – 10% (sloping / wavy), aiming to maintain soil fertility. The creation of a credit terrace begins with making a terrace reinforcement line parallel to the high line and planted with plants such as caliandra.
The mound terraces are made on land that has a slope of 10 – 50% (wavy to slightly steep) and aims to prevent the loss of the soil layer.
Bench terraces are made on land with a slope of 10-30% (hilly and bumpy) and aim to prevent erosion on the slopes planted with secondary crops.
Individual terraces are made on land with slopes between 30 – 50% (rather steep) which are planned for plantation planting areas in areas with little rainfall and good ground cover.
The garden terraces are made on land with slopes between 30 – 50% (rather steep) which are planned for planting plantation types. The making of this terrace is only carried out on the plant path so that in the area there is land that is not terraced and is usually covered by ground cover vegetation.
Channel terraces or better known as rorak or dead-end trenches are soil and water conservation techniques in the form of making dead-end holes made to absorb water into the soil and accommodate sediments from the tillage field.
A stone terrace is the use of stone to create a wall of suitable spacing along contour lines on sloping land.
Making the terrace should be combined with the application of a vegetative system by planting cover crops on the edge of the terrace. Land slope is a quantity expressed in degrees / percent (%) which indicates the angle formed by the difference in altitude.
3. Chemical method
Steady soil structure is one of the soil properties that will determine the level of sensitivity of the soil to erosion. What is meant by chemically conservative methods in preventing erosion is the use of soil ameliorants (s)oil conditioner) or soil stabilizing materials in terms of improving soil structure so that the soil will remain resistant to erosion.
Chemicals as soil conditioner has a very large influence on the level of stability of the aggregate (adhesion) of the soil. The effect is long-term because these compounds will be resistant to microbes found in the soil. Soil permeability (flow) is increased and erosion will be reduced. These materials are also important for improving the growth of annuals on heavy clay soils.
This is the article about Understanding Erosion and Soil Conservation Methods, hopefully useful for all friends. J