Determinants of spatial variability of methane emissions from wet grasslands on peat soil

• Published in: Biogeochemistry 1999-02, Vol.44 (2), p.221-237
• Main Authors: Pol-Van Dasselaar, A. van den, Beusichem, M.L. van, Oenema, O
• Format: Article
• Language: English
• Subjects: Aboveground biomass; biological activity in soil; Bodembiologie; Carbon dioxide; Earth sciences; Earth, ocean, space; Engineering and environment geology. Geothermics; Exact sciences and technology; Grassland soils; Instituut voor Agrobiologisch en Bodemvruchtbaarheidsonderzoek; Methane; methane production; Netherlands; Organic soils; PE&RC; Peat soils; Pollutant emissions; Pollution, environment geology; Production capacity; Research Institute for Agrobiology and Soil Fertility; Soil Biology; Soil organic matter; Soils; Spatial variability; spatial variation; Surficial geology
• ISSN: 0168-2563; 1573-515X
• DOI: 10.1007/BF00992980

Methane (CH4) emissions from soils, representing the consequence of CH4 production, CH4 consumption and CH4 transport, are poorly characterised and show a large spatial variability. This study aimed to assess the determinants of field-scale spatial variability of CH4 emissions from wet grasslands on peat soil. Mean CH4 emission rates of a three-year experiment at 18 plots distributed over three sites in the nature preserve "Nieuwkoopse Plassen" on peat soil in the Netherlands were related to CH4 production and CH4 consumption capacities of soil layers, and to soil and vegetation characteristics. Spatial variability of CH4 emissions and possible determining factors was high. Annual CH4 emissions ranged from 3 to 37 g CH4 m-2 yr-1. Coefficients of variation (CV) of CH4 emissions were on average 37% among sites and 83% within sites. Most important determinants of spatial variability were CH4 production capacity (average: 211 ng CH4 g-1 dry soil h-1; CV: 131%) and aboveground biomass of sedges (Carex spp.) (average: 0.45 g dm-2; CV: 127%) (P < 0.01). Sedges may affect CH4 emissions by stimulating CH4 transport from anaerobic layers to the surface via their vascular system and/or by serving as substrate for methanogens. For extrapolation of CH4 emissions to larger areas, best results will be obtained by using factors that are easy to determine, like vegetation.