Effects of Changing Temperature on Gross N Transformation Rates in Acidic Subtropical Forest Soils
Open Access
- 10 October 2019
- Vol. 10 (10), 894
- https://doi.org/10.3390/f10100894
Abstract
Soil temperature change caused by global warming could affect microbial-mediated soil nitrogen (N) transformations. Gross N transformation rates can provide process-based information about abiotic–biotic relationships, but most previous studies have focused on net rates. This study aimed to investigate the responses of gross rates of soil N transformation to temperature change in a subtropical acidic coniferous forest soil. A 15N tracing experiment with a temperature gradient was carried out. The results showed that gross mineralization rate of the labile organic N pool significantly increased with increasing temperature from 5 °C to 45 °C, yet the mineralization rate of the recalcitrant organic N pool showed a smaller response. An exponential response function described well the relationship between the gross rates of total N mineralization and temperature. Compared with N mineralization, the functional relationship between gross NH4+ immobilization and temperature was not so distinct, resulting in an overall significant increase in net N mineralization at higher temperatures. Heterotrophic nitrification rates increased from 5 °C to 25 °C but declined at higher temperatures. By contrast, the rate of autotrophic nitrification was very low, responding only slightly to the range of temperature change in the most temperature treatments, except for that at 35 °C to 45 °C, when autotrophic nitrification rates were found to be significantly increased. Higher rates of NO3− immobilization than gross nitrification rates resulted in negative net nitrification rates that decreased with increasing temperature. Our results suggested that, with higher temperature, the availability of soil N produced from N mineralization would significantly increase, potentially promoting plant growth and stimulating microbial activity, and that the increased NO3− retention capacity may reduce the risk of leaching and denitrification losses in this studied subtropical acidic forest.Keywords
Funding Information
- National Natural Science Foundation of China (41830642)
This publication has 62 references indexed in Scilit:
- Net and gross nitrification in tea soils of varying productivity and their adjacent forest and vegetable soilsSoil Science and Plant Nutrition, 2012
- Effects of repeated fertilizer and cattle slurry applications over 38 years on N dynamics in a temperate grassland soilSoil Biology and Biochemistry, 2011
- Autotrophic ammonia oxidation by soil thaumarchaeaProceedings of the National Academy of Sciences of the United States of America, 2010
- Nitrogen balance in forest soils: nutritional limitation of plants under climate change stressesPlant Biology, 2009
- Functional role of DNRA and nitrite reduction in a pristine south Chilean Nothofagus forestBiogeochemistry, 2008
- Estimation of parameters in complex 15N tracing models by Monte Carlo samplingSoil Biology and Biochemistry, 2007
- Linking litter calcium, earthworms and soil properties: a common garden test with 14 tree speciesEcology Letters, 2005
- Nitrification in acid soils: micro-organisms and mechanismsSoil Biology and Biochemistry, 2001
- Analysis of Factors Controlling Soil Organic Matter Levels in Great Plains GrasslandsSoil Science Society of America Journal, 1987
- Nitrification by Heterotrophic Soil MicroorganismsSoil Science Society of America Journal, 1966