Nutritional controls on carbon dioxide and methane emission from Carex-dominated peat soils

TY - JOUR

T1 - Nutritional controls on carbon dioxide and methane emission from Carex-dominated peat soils

AU - Aerts, R

AU - Toet, S

PY - 1997

Y1 - 1997

N2 - Eutrophication of peatlands may have significant effects on emissions of carbon dioxide and methane. This study analyses the effects of nitrogen (28.7 mmol NH4+-N, N), phosphorus (1.78 mmol PO43--P, P) and glucose (2.79 mmol glucose, G) additions on CO2 and CH4 emission from intact soil cores from a Carex-dominated peatland in the Netherlands. The cores (taken from the upper 10cm of the peat profile) were brought to field capacity and aerobically incubated at 20 degrees C for 6 wk. Nutrients were added in the following combinations: 0 (unfertilized control), N, P, NP, G,NG, PG, NPG. All treatments in which glucose was present (G, NG, PG, NPG) stimulated CO2 emission during the first 2 wk of the experiment, but did not lead to increased decay of organic matter. At the end of the experiment, all treatments which included N (N, NG, NP, NPG) showed reduced CO2 emission. This was probably due to pH effects, because the pH in the N fertilized treatments was 0.4-0.8 units lower than in the unfertilized control. Cumulative CO2 emission in the N treatment was lower than in the control, but in the treatments where glucose was added it was higher. There was no effect of P addition on CO2 emission. In all treatments, cumulative CH4 emission was higher than in the control due to an initial stimulation of CH4 emission. Compared within treatments, cumulative CO2-C emission was 35-164 times higher than cumulative CH4-C emission. From these observations we conclude that increased amounts of NH4+-N supply lead to reduction of decay of organic matter in peat soils and thereby to a reduction of gaseous carbon loss from these soils. Nutrient or glucose additions lead only to a short-term increase in methane emissions from peat soils. (C) 1997 Elsevier Science Ltd.

AB - Eutrophication of peatlands may have significant effects on emissions of carbon dioxide and methane. This study analyses the effects of nitrogen (28.7 mmol NH4+-N, N), phosphorus (1.78 mmol PO43--P, P) and glucose (2.79 mmol glucose, G) additions on CO2 and CH4 emission from intact soil cores from a Carex-dominated peatland in the Netherlands. The cores (taken from the upper 10cm of the peat profile) were brought to field capacity and aerobically incubated at 20 degrees C for 6 wk. Nutrients were added in the following combinations: 0 (unfertilized control), N, P, NP, G,NG, PG, NPG. All treatments in which glucose was present (G, NG, PG, NPG) stimulated CO2 emission during the first 2 wk of the experiment, but did not lead to increased decay of organic matter. At the end of the experiment, all treatments which included N (N, NG, NP, NPG) showed reduced CO2 emission. This was probably due to pH effects, because the pH in the N fertilized treatments was 0.4-0.8 units lower than in the unfertilized control. Cumulative CO2 emission in the N treatment was lower than in the control, but in the treatments where glucose was added it was higher. There was no effect of P addition on CO2 emission. In all treatments, cumulative CH4 emission was higher than in the control due to an initial stimulation of CH4 emission. Compared within treatments, cumulative CO2-C emission was 35-164 times higher than cumulative CH4-C emission. From these observations we conclude that increased amounts of NH4+-N supply lead to reduction of decay of organic matter in peat soils and thereby to a reduction of gaseous carbon loss from these soils. Nutrient or glucose additions lead only to a short-term increase in methane emissions from peat soils. (C) 1997 Elsevier Science Ltd.

KW - N-FERTILIZATION

KW - NORTHERN WETLANDS

KW - BLANKET BOG

KW - TEMPERATURE

KW - CH4

KW - PEATLANDS

KW - DECOMPOSITION

KW - OXIDATION

KW - NITROGEN

KW - CO2

M3 - Article

SN - 0038-0717

VL - 29

SP - 1683

EP - 1690

JO - Soil Biology and Biochemistry

JF - Soil Biology and Biochemistry

IS - 11-12

ER -