Effects of temperature, glucose and inorganic nitrogen inputs on carbon mineralization in a Tibetan alpine meadow soil

• Main Authors: Song, Minghua, Jiang, Jing, Cao, Guangmin, Xu, Xingliang
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2010
• Subjects: Soc Mineralization; q(10); c Or n Amendment; Soil Heterotrophic Respiration; Tibetan Plateau; Science & Technology; Life Sciences & Biomedicine; WATER-CONTENT; ORGANIC-CARBON; ALASKAN TUNDRA; BOREAL FOREST; ARCTIC TUNDRA; CO2 EXCHANGE; RESPIRATION; DECOMPOSITION; ECOSYSTEM; FLUXES; Environmental Sciences & Ecology; Agriculture; Ecology; Soil Science; Arctic; Tundra
• Online Access: http://ir.nwipb.ac.cn//handle/363003/1634

High levels of available nitrogen (N) and carbon (C) have the potential to increase soil N and C mineralization We hypothesized that with an external labile C or N supply alpine meadow soil will have a significantly higher C mineralization potential and that temperature sensitivity of C mineralization will increase To test the hypotheses an incubation experiment was conducted with two doses of N or C supply at temperature of 5 15 and 25 C Results showed external N supply had no significant effect on CO(2) emission However external C supply increased CO(2) emission Temperature coefficient (Q(10)) ranged from 113 to 1 29 Significantly higher values were measured with C than with N addition and control treatment Temperature dependence of C mineralization was well-represented by exponential functions Under the control CO(2) efflux rate was 425 g CO(2)-Cm(-2) year(-1) comparable to the in situ measurement of 422 g CO(2)-Cm(-2) year(-1) We demonstrated if N is disregarded microbial decomposition is primarily limited by lack of labile C It is predicted that labile C supply would further increase CO(2) efflux from the alpine meadow soil (C) 2010 Elsevier Masson SAS All rights reserved High levels of available nitrogen (N) and carbon (C) have the potential to increase soil N and C mineralization We hypothesized that with an external labile C or N supply alpine meadow soil will have a significantly higher C mineralization potential and that temperature sensitivity of C mineralization will increase To test the hypotheses an incubation experiment was conducted with two doses of N or C supply at temperature of 5 15 and 25 C Results showed external N supply had no significant effect on CO(2) emission However external C supply increased CO(2) emission Temperature coefficient (Q(10)) ranged from 113 to 1 29 Significantly higher values were measured with C than with N addition and control treatment Temperature dependence of C mineralization was well-represented by exponential functions Under the control CO(2) efflux rate was ...