Organic Matter: Difference between revisions
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=== Humus === | === Humus === | ||
Humus is considered as a complex formed in soils that are generated from plant residues in different formats by a special process of "humification". 'A complex aggregate of brown to dark colored amorphous substances, which have originated during the decomposition of plant and animal residues by microorganisms, under aerobic and anaerobic conditions, usually in soils, composts, peat bogs, and water basins'. Different humus types can be represented in an advanced state of decomposition, produced from various plant residues at different periods during prehistoric times, and later stratified and compressed by superimposed layers of mineral matter. <ref> Senn, T. L. and Alta R. Kingman, 1973, A review of Humus and Humic Acids. Research Series No. 145, S. C. Agricultural Experiment Station, Clemson, South Carolina.</ref> | Humus is considered as the stable soil organic matter exists as a complex formed in soils that are generated from plant residues in different formats by a special process of "humification". 'A complex aggregate of brown to dark colored amorphous substances, which have originated during the decomposition of plant and animal residues by microorganisms, under aerobic and anaerobic conditions, usually in soils, composts, peat bogs, and water basins'. Different humus types can be represented in an advanced state of decomposition, produced from various plant residues at different periods during prehistoric times, and later stratified and compressed by superimposed layers of mineral matter. <ref> Senn, T. L. and Alta R. Kingman, 1973, A review of Humus and Humic Acids. Research Series No. 145, S. C. Agricultural Experiment Station, Clemson, South Carolina.</ref> | ||
=='''Importantce of Organic Matter'''== | |||
=== Physical Benefits === | |||
* Improves soil structure, which further helps to control [[soil erosion]], improves water infiltration and water holding capacity. | |||
* Reduces surface crusting, facilitating seedbed preparation. | |||
* Provides better living conditions to [[plant roots]] and soil [[organisms]]. | |||
=== Chemical Benefits === | |||
* Improves the capacity of a soil to store and supply essential nutrients (e.g. nitrogen, phosphorus, potassium, calcium and magnesium). | |||
* Improves the ability of a soil to resist pH change (buffering capacity). | |||
* Improves the capacity of a soil to retain toxic elements. | |||
* Allows the soil to cope with changes in soil acidity. | |||
* Helps accerelate soil minerals to decomposition, making the nutrients in the minerals available for plant uptake. | |||
=== Biological Benefits === | |||
* Supports soil functionality as a primary source of carbon which gives energy and nutrients to [[soil organisms]]. | |||
* Improves the activity of microorganisms in the soil and enhances biodiversity. | |||
# Drcrease the emssions of CO<sup>2</sup> to the atmostphere by capturing carbon in the soil, and hence mitigates climate change. | |||
==References== | ==References== | ||
{{reflist}} | {{reflist}} | ||
Revision as of 21:31, 8 April 2022
Soil organic matter is the fraction of the soil that consists of plant or animal tissue in various stages of breakdown (decomposition). [1] Soil organic matter takes only a few percent of most soils, but it has a great deal of influence on soil properties and agricultural productivity. [2] In the production of a fertile soil, organic substances play a direct part as they are the sources of plant nutrients which are liberated in available forms during mineralization. [3]
Formation Source
Plant residues and microbial biomass
Microbial biomass (bacteria and fungi) is a measure of the mass of the living component of soil organic matter. The microbial biomass decompose plant and animal residues and soil organic matter to release carbon dioxide and plant available nutrients. Farming systems that return plant residues (e.g. no-tillage) tend to increase the microbial biomass. Soil properties such as pH, clay, and the availability of organic carbon all influence the size of the microbial biomass. [4]
Detritus
Detritus is living organic matter composed of leaves and other plant parts, animal remains, waste products, and other organic debris that falls onto the soil or into bodies of water from surrounding terrestrial communities. Microorganisms (such as bacteria or fungi) break down detritus, and this microorganism-rich material is eaten by invertebrates, which are in turn eaten by vertebrates. Many freshwater streams have detritus rather than living plants as their energy base. [5]
Humus
Humus is considered as the stable soil organic matter exists as a complex formed in soils that are generated from plant residues in different formats by a special process of "humification". 'A complex aggregate of brown to dark colored amorphous substances, which have originated during the decomposition of plant and animal residues by microorganisms, under aerobic and anaerobic conditions, usually in soils, composts, peat bogs, and water basins'. Different humus types can be represented in an advanced state of decomposition, produced from various plant residues at different periods during prehistoric times, and later stratified and compressed by superimposed layers of mineral matter. [6]
Importantce of Organic Matter
Physical Benefits
- Improves soil structure, which further helps to control soil erosion, improves water infiltration and water holding capacity.
- Reduces surface crusting, facilitating seedbed preparation.
- Provides better living conditions to plant roots and soil organisms.
Chemical Benefits
- Improves the capacity of a soil to store and supply essential nutrients (e.g. nitrogen, phosphorus, potassium, calcium and magnesium).
- Improves the ability of a soil to resist pH change (buffering capacity).
- Improves the capacity of a soil to retain toxic elements.
- Allows the soil to cope with changes in soil acidity.
- Helps accerelate soil minerals to decomposition, making the nutrients in the minerals available for plant uptake.
Biological Benefits
- Supports soil functionality as a primary source of carbon which gives energy and nutrients to soil organisms.
- Improves the activity of microorganisms in the soil and enhances biodiversity.
- Drcrease the emssions of CO2 to the atmostphere by capturing carbon in the soil, and hence mitigates climate change.
References
- ↑ Department of Crop and Soil Sciences,Soil Organic Matter, Agronomy Fact Sheet Series - Fact Sheet 41, Cornell University Cooporative Exentensive.
- ↑ Grubinger, V. Soil Organic Matter: The Living, the Dead, and the Very Dead https://www.uvm.edu/vtvegandberry/factsheets/soilorganicmatter.html.
- ↑ Senn, T. L. and Alta R. Kingman, 1973, A review of Humus and Humic Acids. Research Series No. 145, S. C. Agricultural Experiment Station, Clemson, South Carolina.
- ↑ Soil Quality Fact Sheet. https://soilquality.org.au/factsheets/microbial-biomass#:~:text=Microbial%20biomass%20(bacteria%20and%20fungi,dioxide%20and%20plant%20available%20nutrients.
- ↑ Britannica. https://www.britannica.com/science/detritus
- ↑ Senn, T. L. and Alta R. Kingman, 1973, A review of Humus and Humic Acids. Research Series No. 145, S. C. Agricultural Experiment Station, Clemson, South Carolina.