Matter dead organic

Dead vegetation also afreets the global carbon cycle. Dead organic matter decomposes, releasing carbon dioxide to the atmosphere. Rates of decomposition vary with material, location, and climate. Non-woody organic matter decomposes rapidly woody organic matter slowly. Decomposition tends to occur faster at the soil surface than below. Decomposition is relatively fast in warm moist climates. In cold climates and in wetlands, decomposition is so slow that there is a net increase of stored carbon in the soil and organic soils called, "histosols, are formed. 

Fluxes are linear functions of reservoir contents. Reservoir size and the residence time of the carbon in the reservoir are the parameters used in the functions. Between the ocean and the atmosphere and within the ocean, fluxes rates are calculated theoretically using size of the reservoir, surface area of contact between reservoirs, concentration of CO2, partial pressures of CO2, temperature, and solubility as factors. The flux of carbon into the vegetation reservoir is a function of the size of the carbon pool and a fertilization effect of increased CO2 concentration in the atmosphere. Flux from vegetation into the atmosphere is a function of respiration rates estimated by Whittaker and Likens (79) and the decomposition of short-lived organic matter which was assumed to be half of the gross assimilation or equal to the amount transferred to dead organic matter. Carbon in organic matter that decomposes slowly is transferred... 

Fig. 3-9 Trophic levels in ecosystems. Thin arrows show flow of energy up the food chain (through living biomass) and the broad arrows show the complementary flow of dead organic matter (detritus) back down. R indicates respiration.

The biomass of Tundra ecosystems gradually increases from 4-7 ton/ha for moss-lichen tundra to 28-29 ton/ha by dry weight for low-bush tundra. In the northern tundra, the plant biomass and dead organic matter are eventually shared. Southwards this percentage tends to diminish, and low-bush living biomass is smaller than dead plant remains mass. A typical feature of the Tundra ecosystems plant species is the prevalence of underground matter (roots) up to 70-80% of the total biomass. 

There are significant differences between biogeochemical cycling in forest and swampy ecosystems of the Boreal climate zone. The annual growth (NPP) of moor vegetation is about 3.5 ton/ha, which is twice as small as that in a forest ecosystem. In the bog, the degradation of dead organic matter proceeds at a much smaller rate than in the forest. The mass of peat accumulated within a period of 100 years accounts for... 

The content of heavy metals in Steppe soils is tightly connected with their contents in geological rocks. In formation of soil exposure pathways in Desert ecosystems, water-soluble forms of these metals play the most important role. We can see an analogy between the increasing content of elements in soil dead organic matter as a function of decreasing water excess in Forest ecosystems and the increasing content of water-soluble species of chemical elements in the soils of Dry Steppe and Desert ecosystems as a function of enhanced aridity. The accumulation of water-soluble species occurs in the upper horizon for almost all elements, with exception of strontium. The main factor responsible for the accumulation of water-soluble forms is connected with evapotranspiration. 

Since methane is produced mainly by microbial decomposition of dead organic matter in swamps, bogs and refuse piles, the close correlations between changes in methane, C02, and temperature suggest that biological processes are involved. 

However raising the temperature in the soils by a few degrees may increase the activity rates of bacteria that convert dead organic matter into... 

BioEnviroTech, Inc., is a supplier of bacterial products based upon natural saprophytic (those that digest only dead organic matter) and facultative (those that can modify their metabolism to live in the presence of free oxygen and with exposure to sunlight) bacteria for bioremediation. The technology is commercially available and has been tested by the National Environmental Technology Applications Center (NETAC) of the University of Pittsburgh Applied Research Center. 

Saprobe An organism living on dead organic matter. 

Many organic reactions are slow at low temperatures but are considerably accelerated by temperature increases (I). In addition, living organisms themselves, such as chemoautotrophic bacteria, may accelerate reactions involving dead organic matter. 

Natural organic matter (NOM) Complex mixtures of organic compounds that result from the partial decay of plants and other dead organisms. NOM commonly occurs in natural waters, soils, and sediments. 

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