Elevated levels of nitrogen and phosphorus were added to soils in northern hardwood forests to test their effects on microbial biomass. Microbial cells were lysed using the chloroform fumigation method to measure the nutrient content of the biomass and determine which nutrient, nitrogen or phosphorus, most limited microbial growth. Previous results suggested phosphorus limitation and nitrogen suppression of microbial biomass. Further analysis is being conducted to measure the effects on total biomass carbon and nutrient ratios to better understand the response of microbial biomass and nutrients to the additions of nitrogen and phosphorus.
WhatsUpp In... Alpine Region concerning Hydrogen Valleys - 16 mai 2024
Does elevated N or P increase the microbial biomass in the soils of the northern hardwood forests?
1. Does elevated N or P increase the microbial biomass in the soils of the northern hardwood forests?
Cindy Sosa
Pictures taken by Cindy Sosa
and Caitlin Buchheim
• Microbes need nitrogen for proteins and need
phosphorus for genetic material and protein synthesis.
• Tested which nutrient to microbial biomass was more
limiting.
• Chloroform fumigation method was used to lyse
microbial cells, measure nutrient cotent of biomass.
2 years ago: Results suggested P limitation and N
suppression.
• What were the effects on the total biomass Carbon?
• I am measuring remaining chemical analyses for C, N,
& P to test for the biomass and nutrient ratio response.
Ribosomes and protein synthesis, genetic material – P
N for proteins
Test which nutrient is more limiting…in the MELNHE experiment
2 yrs ago: p inc. p, n dec. n
We don’t know if it was the actual biomass change
Carbon gives an estimate of microbial biomasss
But we don’t know the total biomass (C) – we are not sure if this is microbe concentration or biomass change. So are the microbes consuming the nutrients and using it or are they just left behind.?
