Mineralization and microbial immobilization of N and P in arctic soils in relation to season,temperature and nutrient amendment |
| |
| Institution: | 1. School of Life Science, East China Normal University, Shanghai 200062, PR China;2. School of Life Science, Huzhou Normal University, Huzhou, Zhejiang 313000, PR China;3. School of Biological Sciences, Flinders University, Adelaide, SA 5001, Australia;1. State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China;2. University of Chinese Academy of Sciences, Beijing 100049, China;3. INRA, UR 874, Grassland Ecosystem Research Team, Clermont-Ferrand, France;4. Department of Science, Information Technology and Innovation (DSITI), Dutton Park, QLD 4102, Australia;5. Environmental Futures Research Institute, Griffith University, Nathan, QLD 4111, Australia;6. AgResearch Limited, Ruakura Research Centre, Hamilton 3240, New Zealand;1. School of Biological Sciences, University of Tasmania, Private Bag 55, Hobart, Tasmania 7001, Australia;2. Land & Environmental Management, AgResearch, Palmerston North, New Zealand;1. Department of Engineering, Aarhus University, Blichers Allé 20, 8830 Tjele, Denmark;2. Department of Agroecology, Aarhus University, Blichers Allé 20, 8830 Tjele, Denmark;3. Department of Environmental Microbiology, Helmholtz Centre for Environmental Research-UFZ, 04318 Leipzig, Germany;1. School of Biological Sciences, Monash University, Victoria 3800, Australia;2. School of Chemistry, Monash University, Victoria 3800, Australia;3. Department of Environment and Primary Industries, Victoria, Australia;4. School of Agriculture, Food and Wine, University of Adelaide Waite Campus, Urrbrae, South Australia 5064, Australia |
| |
| Abstract: | In situ summer, winter and annual net N and P mineralization and microbial immobilization of mineralized nutrients were measured in a low-altitude subarctic/alpine dwarf shrub heath and in a high-altitude fellfield. Net mineralization was determined by using the buried-bag technique, which was combined with fumigation–extraction to recover microbial nutrients and estimate microbial nutrient immobilization. The measurements were carried out in unperturbed plots and in plots, which had been subjected to elevated temperature and fertilizer addition for 5 years before the experiment started. During the growing season, the microbes in the unperturbed plots immobilized the major part of the mineralized nutrients, which resulted in low net mineralization. This occurred also during winter, when we assumed that nutrients should be released during microbial die-back. However, we found no evidence for a large microbial winter die-back and the surviving microbial biomass even immobilized extra nutrients.Soil temperature enhancement by ca. 2°C in general increased, or tended to increase, net mineralization. However, there was not necessarily any strong correlation between net mineralization and temperature because temperature-induced increase in gross mineralized nutrients could either lead to nutrient immobilization in the microbes or the nutrients could be released to the soil inorganic pool.Fertilizer additions had no major effect on net nutrient mineralization or nutrient immobilization. However, the ligno-cellulose index, which has been used as a predictor of substrate quality and usually correlates negatively with decomposition rate, also appeared to be a good predictor of gross mineralization, but a poor predictor of net mineralization. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
