Total microbial carbon and nitrogen were estimated as the difference between fumigated and unfumigated samples (expressed on an oven-dry mass basis), divided by appropriate conversion factors [44] [45].
The N balance and microbial nitrogen supply were remarkably improved when LLP supplementation level increased.
Soil particle size, soil carbon, respiration, microbial biomass and extractable nitrogen were also determined.
In addition, particulate organic matter (POM) as well as microbial biomass carbon and nitrogen were analyzed after 51 days of incubation.
In 2007, soil total nitrogen, available nitrogen, and soil organic carbon contents were increased by 10.2 27.9, 8.0 16.0, and 10.2 30.6%, respectively, in treatments with urea application rates of 0.5 to 2 U compared to control (0 U). Microbial biomass carbon and nitrogen were also increased by 3.1 30.8 and 1.3 13.9%, respectively, in treatments with urea application.
The carbon provides the primary energy source for microbial metabolism, and nitrogen is critical for microbial population growth (Stoffella and Kahn 2001).
Duodenal microbial nitrogen flow was positively correlated with ARS of riboflavin, niacin, vitamin B6, folates, and vitamin B12, but tended to be negatively correlated with thiamin ARS.
Microbial nitrogen supply was higher (P<0.05) in GOS supplemented sheep than those given control, YS and NS diets.
Microbial nitrogen yield was only different (P<0.05) when using reticulum and 15N from those estimated using abomasum and 15N.
The inhibitory effect of oxygen on microbial nitrogen fixation is documented for many bacteria.
