Nitrogen and phosphorus constrain labile and stable carbon turnover in lowland tropical forest soils |
| |
| Institution: | 1. Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK;2. School of Geosciences, University of Edinburgh, Drummond Street, Edinburgh EH8 9XP, UK;3. Smithsonian Tropical Research Institute, Apartado 0843-03092, Balboa, Ancón, Panama;4. Centre of Ecology and Hydrology, Lancaster Environment Centre, Lancaster LA1 4AP, UK;1. Huitong Experimental Station of Forest Ecology, State Key Laboratory of Forest and Soil Ecology, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110164, PR China;2. Huitong National Research Station of Forest Ecosystem, Huitong 418307, PR China;3. Shandong Agricultural University, Taian 271018, PR China;4. University of Chinese Academy of Sciences, Beijing 100049, PR China;1. Centre for Environmental Risk Assessment and Remediation (CERAR), University of South Australia, SA, 5095, Australia;2. Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), University of South Australia, SA, 5095, Australia;3. CSIRO Land and Water/Sustainable Agriculture Flagship, PMB 2, Glen Osmond, SA, 5064, Australia;1. Laboratoire des Radio-Isotopes, BP 3383, Route d''Andraisoro, 101 Antananarivo, Madagascar;2. Eco&Sols, IRD, INRA, CIRAD, SUPAGRO, Université de Montpellier, Montpellier, France;3. Eco&Sols, IRD, Laboratoire des Radio-Isotopes, BP 3383, Route d''Andraisoro, 101 Antananarivo, Madagascar;1. Department of Soil Science of Temperate Ecosystems and Department of Agricultural Soil Science, University of Göttingen, Germany, Büsgen-Institute, Büsgenweg 2, 37077 Göttingen, Germany;2. Department of Range and Wildlife Sciences, South Eastern Kenya University, Kenya, P.O. Box 170-90200, Kitui, Kenya;3. Agro-Technology Institute, RUDN University, Moscow, Russia;4. Institute of Environmental Sciences, Kazan Federal University, Kremlevskaya, 18, 420049, Kazan, Russia;1. Swedish University of Agricultural Sciences (SLU), Department of Ecology, Box 7044, 75007 Uppsala, Sweden;2. Thuenen Institute of Climate-Smart Agriculture, Bundesallee 50, 38116 Braunschweig, Germany;3. Swedish University of Agricultural Sciences (SLU), Department of Soil and Environment, Box 7014, 75007 Uppsala, Sweden |
| |
| Abstract: | Tropical forests contain a large stock of soil carbon, but the factors that constrain its mineralization remain poorly understood. Microorganisms, when stimulated by the presence of new inputs of labile organic carbon, can mineralize (‘prime’) soil organic matter to acquire nutrients. We used stable carbon isotopes to assess how nutrient demand and soil properties constrain mineralization of added labile (sucrose) carbon and pre-existing (primed) soil carbon in tropical forest soils. In a series of lowland tropical forest soils from Panama, we found that the mineralization of fresh labile carbon was accelerated foremost by phosphorus addition, whereas the mineralization of pre-existing soil carbon was constrained foremost by nitrogen addition. However, there was variation in the relative importance of these nutrients in different soils and the largest effects on the acceleration of sucrose metabolism and constraint of priming occurred following the addition of nitrogen and phosphorus together. The respiration responses due to sucrose or primed soil carbon mineralization were reduced at pH below 4.8 and above 6.0. We conclude that in these tropical forest soils, phosphorus availability is more important in promoting microbial mineralization of sucrose carbon, whereas nitrogen availability is more important in constraining the priming of pre-existing soil organic carbon. This response likely arises because nitrogen is more closely coupled to organic matter cycling, whereas phosphorus is abundant in both organic and inorganic forms. These results suggest that the greatest impact of priming on soil carbon stocks will occur in moderately acidic tropical forest soils of low nitrogen availability. Given long-term changes in both atmospheric carbon dioxide and nitrogen deposition, the impact of priming effects on soil carbon in tropical forest soils may be partially constrained by the abundance of nitrogen. |
| |
| Keywords: | Carbon dioxide Nitrogen Phosphorus Priming effects Microorganisms Stable isotopes |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
