Organic matter exogenous

Biological exposure pathway of sulfur movement in soils of forest ecosystems is related to microbial transformation of sulfolipids. Back conversion of sulfate-S into organic matter immobilizes the anion and potentially reduces soil cation leaching. Processes of sulfur mineralization and incorporation proceed rapidly in response to several factors, including temperature, moisture, and exogenous sulfate availability in soils and water. 

Sanchez-Camazano M, Sanchez-Martm MJ, Poveda E, Iglesias-Jimdnez E. Study of the effect of exogenous organic matter on the mobility of pesticides in soil using soil thin-layer chromatography. J. Chromatogr. A 1996 754 279-284. 

Matrajt G, Pizzarello S, Taylor S, Brownlee D. Concentration and variability of the AIB amino acid in polar micrometeorites Implications for the exogenous delivery of amino acids to the primitive Earth. Meteorit. Planet. Sci. 2006 128 7412-7413. Busemann H, Young, AE, Alexander, CMO D, Hoppe, P, Mukhopadhyay, S, Nitter, LR. Interstellar chemistry recorded in organic matter from primitive meteorites. Science 2006 312 727-730. 

The two dominant exogenic reservoirs of carbon are carbonate rocks and organic matter in sediments. They are linked in the carbon cycle via atmospheric CO2 and the carbon species dissolved in the hydrosphere. The for the total... 

Rittenberg, S.G., 1969. The roles of exogenous organic matter in the physiology of chemolithotophic bacteria. Adv. Microb. Physiol., 3 159—196. 

The importance of exogenous delivery of organic matter to the early Earth is critically dependent on the survivability of organic compounds during the delivery process. It is presently unclear exactly how much organic material would escape destruction during asteroid, comet and interplanetary dust particle infall to the Earth s surface. 

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