– loss of soil
– process of soil erosion where soil is detached from its place and transferred to another place. it is soil erosion.
Detachment of soil particles- in field soil is there and particles are aggregated & get detached
These detached particles are transported- they are transported to another place where they are deposited or lost anywhere.
# These two processes are carried by 2 agents/forces i.e. water & wind
-Water & wind are responsible for detachment and transported of soil particles & they are known as erosion agents.
Under natural conditions due to rain or wind there will be erosion of soil. In every situation there is natural erosion by wind & water. This natural erosion causes loss of soil but this loss of soil is compensated by soil formation process.
In natural conditions there are 2 processes-
Soil formation process by rock weathering- physical, chemical or biological weathering.
Factors (wind & water- natural agents) we cannot change rainfall pattern or wind speed to reduce erosion, we can’t control it for an area but the practices that is being done in that area- cultivation practices, farm practices it increases the rate of erosion.
2.1 Saltation- (Jumping action)- when wind flows, it makes pressure/hit soil particles, particles move into air and again come back to surface-jumping action.
– about 30-60 cm above from surface.
– medium size particles about 0.1mm-0.5mm
– 50-75% soil is eroded by saltation
2.2 Surface creeping-(rolling action) particles roll on surface, they do not come into the air-particles are heavy, they can’t come into air. Wind makes pressure on it & they start rolling on surface. Rolling is not for much distance.
– particle size- >0.5mm
– 5-20% soil is eroded
2.3 Suspension-(floating action) very small particles come into air & start floating in air. Particles are very small so they travel long distances.
– particle size- <0.1mm
– 3-4% soil is eroded
– If erodibility is high, soil is more prone to erosion | Erosivity– erosion causing power of agent (power of wind & water to cause erosion) – Erosivity more, erosion will be more. |
3.1 Aggregation- In soil particles are present in aggregates. If aggregation is more then there is more water stable aggregate, then detachment will be less, erodibility will be less & less chances of soil erosion
– if aggregation is good in soil, there is less chance of erosion.
3.2 Slope (Steepness)- if slope is more, water runoff is more, it will detach and transport the soil more.
3.3 Slope Length- if slope length is more, erosion will be more.
3.4 Physical characteristics in relation to aggregation- the soil having more aggregation, detachment will be less & transportation will be less.
Sandy (Coarse textured) | Clay (Fine textured) |
---|---|
In sandy soil aggregation is poor, detachment is easy but transportation is low because sand particles are heavy | In clay aggregation is more & detachment is less but transportation is easy & light particles are transported easily. |
Sand | Clay | |
---|---|---|
Detachment | Easy | Difficult |
Transport | Difficult | Easy |
Infilteration | Easy b/c macropores are there | Low b/c micropores, sealing of pores |
Runoff | less | more |
When land is worked through crops or other agricultural processes, it reduces the overall structure of the soil, reducing the levels of organic matter, making it more susceptible to the effects of rain and water. Tilling often breaks up and softens the structure of the soil, can be a major contributor to erosion
Unsheltered distance with lack of windbreaks such as trees, shrubs, crop residue, etc. make way for the wind to put soil particles into motion for greater distances, thereby increasing soil erosion. Knolls and hilltops are usually exposed without any vegetation cover and suffer the most.
1. Careful Tilling- Because tilling activity breaks up the structure of the soil, doing less tilling with fewer passes will preserve more of the crucial topsoil.
2. Crop Rotation- Plenty of crop rotation is crucial for keeping land happy and healthy. This allows organic matter to build up, making future plantings more fertile.
3. Increased Structure For Plants- Introducing terraces or other means of stabilizing plant life or even the soil around them can help reduce the chance that the soil loosens and erodes. Boosting areas that are prone to erosion with sturdy plant life can be a great way to stave off future effects.
4. Water Control- For those areas where soil erosion is predominantly caused by water – whether natural or man-made – specialized chutes and runoff pipes can help to direct these water sources away from the susceptible areas, helping stave off excess erosion. Having these filters in particular areas rather than leading to natural bodies of water is a focus to reduce pollution.
5. Soil Conservation- Soil conservation can be defined as “the combination of the appropriate land use and management practices that promotes the productive and sustainable use of soils and, in the process, minimizes soil erosion and other forms of land degradation.”
Various measures for soil conservation are primarily meant for the prevention of soil loss or reduced fertility caused by acidification, over usage, salinization or other chemical soil contamination.
Different techniques for improved soil conservation involve cover crops, crop rotation, planted windbreaks, and conservation tillage and affect both fertility and erosion.
6. Increased Knowledge- A major factor for preventing soil erosion is educating more and more people who work with the land on why it is a concern, and what they can do to help reduce it.
This means outreach to farmers in susceptible areas for ways that they can help protect crops from inclement weather or ways that they can help make sure their soil remains compact without restricting their plant growing activities.
Soil provides the nutrients essential for plant growth, animal life, and millions of microorganisms. Soil conservation focuses on keeping soils healthy through a combination of practices and techniques. Soil conservation helps to ensure that soil is fertile and productive, and protect it from erosion, degradation & depletion.
The major objective of conservation of the soil is maintaining its biodiversity of inhabiting eco-communities that contribute to its fertility in their own ways. They add organic matter, split perished organisms to release nutrients, improve water infiltration, and aeration.