Soil erosion (soil erosion) is a process of ground washing and is a natural phenomenon that is natural and continues as long as there is flow on the surface. Erosion is balanced with the rate of soil formation so that the land undergoes continuous rejuvenation. Soil erosion turns into a danger if the process progresses faster than the rate of soil formation. Rapid erosion will attenuate the soil, and eventually can make ground material such as bedrock to the ground surface.
This erosion will damage upstream areas affected by direct erosion, as well as downstream areas. The erosion material deposited in the downstream area will adversely affect the building or natural body of storage or water supply causing a trail which results in the capacity of the container or channel to decrease rapidly and damage the land and settlement.
Erosion will cause a decline in the quality of agricultural land in Indonesia. At the time of the rainy season 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 tropics wet. Soils lost due to erosion are fertile topsoil, so the erosion will decrease soil fertility significantly.
In slope soils, erosion is also a serious issue. Where the slope and slope length are two slope elements that affect the surface flow and erosion. If the velocity increases twice, then the clumps of clogged soil become 32-fold. On deforested soil, will cause water flow disruption that will cause damage to road infrastructure and facilities.
DEFINING CONSERVATION METHOD
Conservation is an attempt to keep the land productive or to repair soil damaged by erosion. Conservation measures have certain criteria, such as one of the considerations is the value of the limit of erosion that can still be ignored (tolerable soil loss). There are three selection of conservation techniques, namely:
- Vegetative method
Namely any use of plants / vegetation as a protective soil from erosion, inhibition of surface flow rate, increased moisture content of the soil, and improvement of soil properties, both physical, chemical, and biological. Plants or crop residues serve as a protective soil against rainwater punching forces as well as on runoff water carrying capacity, as well as increasing infiltration of water into the soil.
One example is the vetiver grass, known as the fragrant root, or usar. Namely plants with grass that is large and have many functions. Utilization of this plant is called the Vetiver System (VS). Which VS is a technology that utilizes vetiver plants that are still alive for soil conservation.
- Mechanical Method
The mechanical way is the way of land management using physical facilities such as soil or rock 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 the flow of surface water.
Included in this method is the soil treatment method. This soil processing works to create soil conditions that make plants easy to grow on it including making rorak (sewer) and making terracing. The purpose of soil preparation is to prepare seedlings, create good root areas, remove plant debris and eradicate weeds.
Technical and mechanical erosion controls are soil maintenance efforts to reduce the amount of land losing their function in agricultural areas in a particular way. In relation to mechanical soil improvement efforts it is aimed at slowing the flow of the surface and accommodating and continuing the distribution of surface flows with a non-destructive soil removal such as https://www.maccaferri.com/my/applications/erosion-control/.
- Chemical methods
Strong soil structure is one of the soil properties that will determine the degree of soil sensitivity to erosion. What is meant by chemical conservative methods in erosion prevention is by the use of soil conditioner or soil ingredients in terms of improving soil structure so that the soil will remain resistant to erosion.
Chemicals as soil conditioner have a very big influence on the level of aggregate stability (adhesion) of the soil. The effect is long-term because the compound will be resistant to microbes found on the soil. The permeability (flow) of the soil is heightened and the erosion will decrease. These materials also have important consequences for improving the growth of seasonal crops on heavy clays.