Molecular-level chemical characterization and bioavailability of dissolved organic matter in stream water using electrospray-ionization mass spectrometry

摘要: We used electrospray-ionization mass spectrometry (ESI-MS) to characterize, at the compound level, dissolved organic matter (DOM) composition and bioavailability in two streams. There was considerable consistency of DOM between streams (unit resolution): .70% masses detected occurred both Approximately 40‐50% bulk carbon stream water bioavailable during a 12-d microbial decomposition experiment. ESI-MS level analysis identified which were used, not, their patterns utilization. In streams, ;40% decreased concentration, ;55% did not change, ,5% increased. Despite complex system (.1,500 compounds natural consortia bacteria), there high degree similarity amount each replicate flasks for stream. also good agreement used. This suggests that selection by heretofore largely uncharacterized pool is repeatable and, therefore, ultimately predictable.