A kinetic approach to evaluate salinity effects on carbon mineralization in a plant residue-amended soil.
The interaction of salinity stress and plant residue quality on C mineralization kinetics in soil is not well understood. A laboratory experiment was conducted to study the effects of salinity stress on C mineralization kinetics in a soil amended with alfalfa, wheat and corn residues. A factorial combination of two salinity levels (0.97 and 18.2 dS/m) and four levels of plant residues (control, alfalfa, wheat and corn) with three replications was performed. A first order kinetic model was used to describe the C mineralization and to calculate the potentially mineralizable C. The CO(2)-C evolved under non-saline condition, ranged from 814.6 to 4842.4 mg CO(2)-C/kg in control and alfalfa residue-amended soils, respectively. Salinization reduced the rates of CO(2) evolution by 18.7%, 6.2% and 5.2% in alfalfa, wheat and corn residue-amended soils, respectively. Potentially mineralizable C (C(0)) was reduced significantly in salinized alfalfa residue-treated soils whereas, no significant difference was observed for control treatments as well as wheat and corn residue-treated soils. We concluded that the response pattern of C mineralization to salinity stress depended on the plant residue quality and duration of incubation.
Nourbakhsh
Farshid
F
Department of Soil Science, School of Agriculture, Isfahan University of Technology, Isfahan 84154, Iran. farshid@cc.iut.ac.ir
Sheikh-Hosseini
Ahmad R
AR
D002244:Carbon / Q000737:chemistry*; D002245:Carbon Dioxide / Q000737:chemistry; D002482:Cellulose / Q000378:metabolism; D017753:Ecosystem; D007700:Kinetics; D000455:Medicago sativa / Q000378:metabolism*; D008956:Models, Chemical; D010944:Plants / Q000378:metabolism*; D012492:Salts / Q000737:chemistry / Q000494:pharmacology; D012987:Soil; D012989:Soil Pollutants; D014908:Triticum / Q000378:metabolism; D003313:Zea mays / Q000378:metabolism
D012492:Salts; D012987:Soil; D012989:Soil Pollutants; D002245:Carbon Dioxide; D002244:Carbon; D002482:Cellulose