Long-term rice cultivation stabilizes soil organic carbon and promotes soil microbial activity in a salt marsh derived soil chronosequence.
Soil organic carbon (SOC) sequestration with enhanced stable carbon storage has been widely accepted as a very important ecosystem property. Yet, the link between carbon stability and bio-activity for ecosystem functioning with OC accumulation in field soils has not been characterized. We assessed the changes in microbial activity versus carbon stability along a paddy soil chronosequence shifting from salt marsh in East China. We used mean weight diameter, normalized enzyme activity (NEA) and carbon gain from straw amendment for addressing soil aggregation, microbial biochemical activity and potential C sequestration, respectively. In addition, a response ratio was employed to infer the changes in all analyzed parameters with prolonged rice cultivation. While stable carbon pools varied with total SOC accumulation, soil respiration and both bacterial and fungal diversity were relatively constant in the rice soils. Bacterial abundance and NEA were positively but highly correlated to total SOC accumulation, indicating an enhanced bio-activity with carbon stabilization. This could be linked to an enhancement of particulate organic carbon pool due to physical protection with enhanced soil aggregation in the rice soils under long-term rice cultivation. However, the mechanism underpinning these changes should be explored in future studies in rice soils where dynamic redox conditions exist.
Institute of Resource, Ecosystem and Environment of Agriculture, and Department of Soil Science, Nanjing Agricultural University, Nanjing 210095, China.
Ping
P
Wang
Institute of Resource, Ecosystem and Environment of Agriculture, and Department of Soil Science, Nanjing Agricultural University, Nanjing 210095, China.
Yalong
Y
Liu
Institute of Resource, Ecosystem and Environment of Agriculture, and Department of Soil Science, Nanjing Agricultural University, Nanjing 210095, China.
Lianqing
L
Li
Institute of Resource, Ecosystem and Environment of Agriculture, and Department of Soil Science, Nanjing Agricultural University, Nanjing 210095, China.
Kun
K
Cheng
Institute of Resource, Ecosystem and Environment of Agriculture, and Department of Soil Science, Nanjing Agricultural University, Nanjing 210095, China.
Jufeng
J
Zheng
Institute of Resource, Ecosystem and Environment of Agriculture, and Department of Soil Science, Nanjing Agricultural University, Nanjing 210095, China.
Xuhui
X
Zhang
Institute of Resource, Ecosystem and Environment of Agriculture, and Department of Soil Science, Nanjing Agricultural University, Nanjing 210095, China.
Jinwei
J
Zheng
Institute of Resource, Ecosystem and Environment of Agriculture, and Department of Soil Science, Nanjing Agricultural University, Nanjing 210095, China.|School of Materials Science and Engineering, University of New South Wales, Sydney, NSW 2052, Australia.|Discipline of Chemistry, University of Newcastle, Callaghan, NSW 2308, Australia.
Stephen
S
Joseph
Institute of Resource, Ecosystem and Environment of Agriculture, and Department of Soil Science, Nanjing Agricultural University, Nanjing 210095, China.
Genxing
G
Pan
D000383:Agriculture; D001419:Bacteria / Q000201:enzymology / Q000235:genetics; D018407:Bacterial Physiological Phenomena; D018533:Biomass; D002244:Carbon / Q000032:analysis*; D057965:Carbon Sequestration; D004798:Enzymes / Q000378:metabolism; D012275:Oryza / Q000254:growth & development*; D010316:Particle Size; D012336:RNA, Ribosomal, 16S / Q000032:analysis / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D012987:Soil / Q000737:chemistry*; D012988:Soil Microbiology; D053833:Wetlands
D004798:Enzymes; D012336:RNA, Ribosomal, 16S; D012987:Soil; D002244:Carbon