Humus has a characteristic black or dark brown colour, which is due to an abundance of organic carbon. Carbon (kɑɹbən is a Chemical element with the symbol C and its Atomic number is 6

Humus (Latin - "soil ") is the organic material in soil lending it a dark brown or black colouration. Latin ( lingua Latīna, laˈtiːna is an Italic language, historically spoken in Latium and Ancient Rome. Soil, often typeset as SOiL, is a four piece rock band from Chicago Illinois United States founded by Shaun Glass Tom Schofield Tim King and Adam Zadel

In soil science, humus refers to any organic matter which has reached a point of stability, where it will break down no further and might, if conditions do not change, remain essentially as it is for centuries, if not millennia^[1]. Soil science is the study of Soil as a Natural resource on the surface of the Earth including soil formation, classification and mapping

In agriculture, humus is sometimes also used to describe mature compost, or natural compost extracted from a forest or other spontaneous source for use to amend soil. Compost (ˈkɒmpɒst or US /ˈkɒmpoʊst/ also known as brown manure is the aerobically decomposed remnants of Organic matter. It is also used to describe a topsoil horizon that contains organic matter (humus type, humus form, humus profile). Topsoil is the upper outermost layer of soil usually the top 2 to 8 inches The horizon ( Ancient Greek ὁ ὁρίζων, /ho horídzôn/ from ὁρίζειν, "to limit" is the apparent line that separates Organic matter (or organic material) is Matter that has come from a once-living Organism; is capable of

Humification

The process of "humi"can occur naturally in soil, or in the production of compost. Compost (ˈkɒmpɒst or US /ˈkɒmpoʊst/ also known as brown manure is the aerobically decomposed remnants of Organic matter. Chemically stable humus is thought by some to be important to the fertility of soils in both a physical and chemical sense, though some agricultural experts advocate a greater focus on other aspects of nutrient delivery, instead. Physically, it helps the soil retain moisture, and encourages the formation of good soil structure. Chemically, it has many active sites which bind to ions of plant nutrients, making them more available. Humus is often described as the 'life-force' of the soil. Soil, often typeset as SOiL, is a four piece rock band from Chicago Illinois United States founded by Shaun Glass Tom Schofield Tim King and Adam Zadel Yet it is difficult to define humus in precise terms; it is a highly complex substance, the full nature of which is still not fully understood. Physically, humus can be differentiated from organic matter in that the latter is rough looking material, with coarse plant remains still visible, while once fully humified it becomes more uniform in appearance (a dark, spongy, jelly-like substance) and amorphous in structure. That is, it has no determinate shape, structure or character.

Plant remains (including those that have passed through an animal and are excreted as manure) contain organic compounds: sugars, starches, proteins, carbohydrates, lignins, waxes, resins and organic acids. Plants are living Organisms belonging to the kingdom Plantae. Manure is Organic matter used as Organic fertilizer in Agriculture. Carbohydrates (from ' Hydrates of Carbon ' or saccharides ( Greek σάκχαρον meaning " Sugar " are the most Lignin or lignen is a complex Chemical compound most commonly derived from Wood and an integral part of the secondary Cell walls of Plants An organic acid is an Organic compound with Acidic properties The process of organic matter decay in the soil begins with the decomposition of sugars and starches from carbohydrates which break down easily as saprotrophs initially invade the dead plant, while the remaining cellulose breaks down more slowly. Cellulose is an Organic compound with the formula, a Polysaccharide consisting of a linear chain of several hundred to over ten thousand β(1→4 Proteins decompose into amino acids at a rate depending on carbon to nitrogen ratios. In Chemistry, an amino acid is a Molecule containing both Amine and Carboxyl Functional groups In Biochemistry, this The C/N ratio or Carbon to Nitrogen ratio can amongst other things be used in analysing Sediments and Compost. Organic acids break down rapidly, while fats, waxes, resins and lignins remain relatively unchanged for longer periods of time. The humus, that is the end product of this process, is thus a mixture of compounds and complex life chemicals of plant, animal, or microbial origin, which has many functions and benefits in the soil. Earthworm humus (vermicompost) is considered by some to be the best organic manure there is. Earthworm is the usual name for the largest members of Oligochaeta (which is either a class or subclass depending on the author in the phylum Annelida In classical Vermicompost (also called worm Compost, vermicast worm castings worm humus or worm manure is the end-product of the breakdown of Organic matter by some

Humification of leaf litter and formation of clay-humus complexes

Compost which is readily capable of further decomposition is sometimes referred to as effective or active humus, though again scientists would say that if it is not stable, it's not humus at all. Decomposition (or spoilage) refers to the break down of tissue of a formerly living Organism into simpler forms of matter This kind of compost is principally derived from sugars, starches, and proteins, and consists of simple organic (fulvic) acids. It is an excellent source of plant nutrients, but of little value regarding long-term soil structure and tilth. Stable (or passive) humus consisting of humic acids and humins, on the other hand, are so highly insoluble (or tightly bound to clay particles that they cannot be penetrated by microbes) that they are greatly resistant to further decomposition. Humic acid is one of the major components of humic substances which are dark brown and major constituents of soil organic matter Humus that contributes to Soil chemical Solubility is the characteristic Physical property referring to the ability of a given substance the Solute, to dissolve in a Solvent. Thus they add few readily available nutrients to the soil, but play an essential part in providing its physical structure. Some very stable humus complexes have survived for thousands of years. Stable humus tends to originate from woodier plant materials, eg, cellulose and lignins. Wood is hard fibrous lignified structural tissue produced as secondary Xylem in the stems of Woody plants notably trees but also shrubs Soil animals, which ingest then transform organic matter in their guts, are active agents of humification, in association with fungi and bacteria: most humus in the soil is included in animal faeces of more or less dark colour according to their content in organic matter^[2].

Benefits of humus

• The mineralisation process that converts raw organic matter to the relatively stable substance that is humus feeds the soil population of micro-organisms and other creatures, thus maintaining high and healthy levels of soil life. Soil life or soil biota is a collective term for all the organisms living within the soil
• The rate at which raw organic matter is converted into humus promotes (when fast) or limits (when slow) the coexistence of plants, animals and microbes in terrestrial ecosystems ^[3]
• Effective and stable humus (see below) are further sources of nutrients to microbes, the former providing a readily available supply while the latter acts as a more long-term storage reservoir. Plants are living Organisms belonging to the kingdom Plantae. A microorganism (also spelled micro organism or micro-organism and also called a microbe) is an Organism that is Microscopic (usually An ecosystem is a natural unit consisting of all plants animals and micro-organisms( Biotic factors in an area functioning together with all of the non-living physical ( A microorganism (also spelled micro organism or micro-organism and also called a microbe) is an Organism that is Microscopic (usually
• Humification of dead plant material causes complex organic compounds to break down into simpler forms which are then made available to growing plants for uptake through their root systems.
• Humus is a colloidal substance, and increases the soil's cation exchange capacity, hence its ability to store nutrients by chelation as can clay particles; thus while these nutrient cations are accessible to plants, they are held in the soil safe from leaching away by rain or irrigation. A colloid is a type of mechanical Mixture where one substance is dispersed evenly throughout another In Soil science, cation exchange capacity (CEC is the capacity of a Soil for Ion exchange of positively charged ions between the soil and the Chelation is the binding or complexation of a bi- or multidentate Ligand. Clay is a naturally occurring material composed primarily of fine-grained Minerals which show plasticity through a variable range of Water content, and An ion is an Atom or Molecule which has lost or gained one or more Valence electrons giving it a positive or negative electrical charge Rain is Liquid precipitation. On Earth it is the condensation of atmospheric Water vapor into drops heavy enough to fall often making it to Irrigation is an artificial application of water to the soil usually for assisting in growing crops
• Humus can hold the equivalent of 80-90% of its weight in moisture, and therefore increases the soil's capacity to withstand drought conditions.
• The biochemical structure of humus enables it to moderate — or buffer — excessive acid or alkaline soil conditions. In Computer science, ACID ( Atomicity Consistency Isolation Durability) is a set of properties that guarantee that Database transactions are In Chemistry, an alkali (from Arabic: Al-Qaly القلي القالي) is a basic, ionic salt of an Alkali metal
• During the humification process, microbes secrete sticky gums; these contribute to the crumb structure of the soil by holding particles together, allowing greater aeration of the soil. Aeration is the Process by which Air is circulated through mixed with or dissolved in a Liquid or substance Toxic substances such as heavy metals, as well as excess nutrients, can be chelated (that is, bound to the complex organic molecules of humus) and prevented from entering the wider ecosystem. An ecosystem is a natural unit consisting of all plants animals and micro-organisms( Biotic factors in an area functioning together with all of the non-living physical (
• The dark colour of humus (usually black or dark brown) helps to warm up cold soils in the spring. Spring is one of the four Temperate Seasons Spring marks the transition from Winter into Summer.

See also

• Biomass
• Biotic matter
• Glomalin
• Humic acid
• Organic matter
• Plant litter

References