Influence of nitrogen on cellulose and lignin mineralization in blackwater and redwater forested wetland soils

La Influencia del nitrógeno en la mineralización de celulosa y lignina en aguas negras y rojas de suelos húmedos boscosos

Entry, James A. (2000) Influence of nitrogen on cellulose and lignin mineralization in blackwater and redwater forested wetland soils. Biology & Fertility of Soils. 31:436-440.

	PDF 1019.pdf Download (461kB)
	PDF ES_1019.pdf Download (12kB)

Abstract

Microcosms were used to determine the influence
of N additions on active bacterial and active
fungal biomass, cellulose degradation and lignin degradation
at 5, 10 and 15 weeks in soils from blackwater
and redwater wetlands in the northern Florida panhandle.
Blackwater streams contain a high dissolved organic
C concentration which imparts a dark color to the
water and contain low concentrations of nutrients. Redwater
streams contain high concentrations of suspended
clays and inorganic nutrients, such as N and P,
compared to blackwater streams. Active bacterial and
fungal biomass was determined by direct microscopy;
cellulose and lignin degradation were measured radiometrically.
The experimental design was a randomized
block. Treatments were: soil type (blackwater or
redwater forested wetlands) and N additions (soils
amended with the equivalent of 0, 200 or 400 kg N ha- 1
as NH4NO3 ). Redwater soils contained higher concentrations
of C, total N, P, K, Ca, Mn, Fe, B and Zn than
blackwater soils. After N addition and 15 weeks of incubation,
the active bacterial biomass in redwater soils
was lower than in blackwater soils; the active bacterial
biomass in blackwater soils was lower when 400 kg N
ha', but not when 200 kg N ha-1 , was added. The active
fungal biomass in blackwater soils was higher when
400 kg N ha- 1 , but not when 200 kg N ha- 1 , was added.
The active fungal biomass in redwater wetland soils was
lower when 200 kg N ha- 1 , but not when 400 kg N ha- 1 ,
was added. Cellulose and lignin degradation was higher
in redwater than in blackwater soils. After 10 and
15 weeks of incubation, the addition of 200 or 400 kg N
as NH4NO3 ha-1 decreased cellulose and lignin degradation
in both wetland soils to similar levels. This study
indicated that the addition of N may slow organic matter
degradation and nutrient mineralization, thereby
creating deficiencies of other plant-essential nutrients
in wetland forest soils.

Item Type:	Article
NWISRL Publication Number:	1019
Subjects:	Soil > Chemistry > Nitrogen Mass Import - autoclassified (may be erroneous)
Depositing User:	Dan Stieneke
Date Deposited:	20 Nov 2010 21:50
Last Modified:	15 Nov 2016 15:29
Item ID:	107
URI:	https://eprints.nwisrl.ars.usda.gov/id/eprint/107