作者: I. F. Creed , K. L. Webster , G. L. Braun , R. A. Bourbonnière , F. D. Beall
DOI: 10.1007/S10533-012-9713-4
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摘要: Soil carbon pools are an essential but poorly understood factor in heterotrophic soil respiration on forested landscapes. We hypothesized that the topographically regulated distribution of dissolved organic (DOC) is dominant contributing to CO2 efflux. tested this hypothesis by monitoring efflux and sampling particulate substrates (both mobile DOC solution potentially sorbed onto Fe Al oxyhydroxides) surface (freshly fallen leaves (FFL) forest floor) near-surface (A-horizon or top 10 cm peat) soils along three hillslope transects (15°, 25° 35° slopes) included upland (crest, shoulder, backslope, footslope, toeslope) wetland (periphery central) topographic features during snowfree season within a sugar maple forest. observed median ranged from 5 μmol CO2 m−2 s−1. Substrates mineral were most strongly related efflux, when combined together explained 78% heterogeneity (p < 0.001). When pool FFL (an important source soils) was included, explanation variance increased 81% Topographically processes created high concentrations at further downslope toeslope, forming distinct traps can become hotspots for production. A reduction uncertainty budgets be achieved taking into consideration regulation