Endogeic earthworms lower net methane production in saturated riparian soils

作者：Kernecker Maria; Whalen Joann K^*; Bradley Robert L

来源：Biology and Fertility of Soils, 2015, 51(2): 271-275.

DOI：10.1007/s00374-014-0965-0

• Earthworms
• Methane
• Riparian
• Difluoromethane
• Methanogenesis
• Methanotrophy

Methane (CH4) emissions from soils are erratic, the typical pattern being long periods of imperceptible emissions punctuated by short periods of high CH4 release. These short peaks are a result of higher gross CH4 production rates (methanogenesis) relative to gross rates of CH4 consumption (methanotrophy), and can be induced by rising water table level and periodic flooding in riparian soils. Soil fauna, specifically earthworms, affected soil CH4 cycling in some studies. We studied the effect of the endogeic earthworm Aporrectodea turgida (Eisen) on CH4 production and consumption activities in saturated and field-moist soils collected from a riparian area in southern Qu,bec, Canada. Saturated (100 % water-filled pore space, WFPS) and field-moist soils (31.5 % WFPS) were incubated at 20 A degrees C, with difluoromethane added to quantify gross CH4 production (i.e., methanogenesis activity) and consumption rates (i.e., methanogenic activity). The pattern of gross CH4 consumption followed that of gross CH4 production, and net CH4 production was an order of magnitude lower than the gross rate. Gross rates of CH4 production were 41 to 65 ng CH4 g(-1) h(-1), gross CH4 consumption rates were estimated to be 37 to 63 ng CH4 g(-1) h(-1), and the net CH4 production ranged from 2 to 4 ng CH4 g(-1) h(-1). Saturated soils with earthworms had consistently lower net CH4 production, relative to field-moist and saturated soils without earthworms. This means that earthworms could potentially reduce the impact of periodic flooding on CH4 emissions from riparian soils.

• 出版日期2015-2