TY - JOUR
T1 - Quantifying rates of methanogenesis and methanotrophy in Lake Kinneret sediments (Israel) using pore-water profiles
AU - Adler, Michal
AU - Eckert, Werner
AU - Sivan, Orit
PY - 2011/7/1
Y1 - 2011/7/1
N2 - Full seasonal sets of chemical and isotope profiles from the pore water of Lake Kinneret (Sea of Galilee, Israel) were produced to study methanogenesis and methanotrophy processes and the couplings between methane (CH 4), sulfur, AND iron. Sulfate is depleted within the upper 10 cm of the sediment mainly by traditional bacterial sulfate reduction by organic matter. Maximum sulfate reduction rates calculated from sulfate concentration profiles are found at the water-sediment interface (0-1 cm 2-1.4×3 102 -12 ± 0.2×10 -12 mol cm -3 s -1). CH 4 concentrations and modeling of dissolved inorganic carbon (DIC) and its stable carbon isotope (δ 13C DIC) suggest that maximum methanogenesis rates of 2.5 × 10 -13 ± 1.5 × 10 -13 mol cm -3 s -1 occur at 5-12-cm depth in the sediments, AND that it ends at 20 cm. Of the produced CH 4, 50-75% is converted to gas bubbles of CH 4 before it reaches the bottom water. Model results suggest the occurrence of anaerobic oxidation of CH4 (AOM) in the deep sediments of the lake below the zone of methanogenesis.
AB - Full seasonal sets of chemical and isotope profiles from the pore water of Lake Kinneret (Sea of Galilee, Israel) were produced to study methanogenesis and methanotrophy processes and the couplings between methane (CH 4), sulfur, AND iron. Sulfate is depleted within the upper 10 cm of the sediment mainly by traditional bacterial sulfate reduction by organic matter. Maximum sulfate reduction rates calculated from sulfate concentration profiles are found at the water-sediment interface (0-1 cm 2-1.4×3 102 -12 ± 0.2×10 -12 mol cm -3 s -1). CH 4 concentrations and modeling of dissolved inorganic carbon (DIC) and its stable carbon isotope (δ 13C DIC) suggest that maximum methanogenesis rates of 2.5 × 10 -13 ± 1.5 × 10 -13 mol cm -3 s -1 occur at 5-12-cm depth in the sediments, AND that it ends at 20 cm. Of the produced CH 4, 50-75% is converted to gas bubbles of CH 4 before it reaches the bottom water. Model results suggest the occurrence of anaerobic oxidation of CH4 (AOM) in the deep sediments of the lake below the zone of methanogenesis.
UR - http://www.scopus.com/inward/record.url?scp=84858242133&partnerID=8YFLogxK
U2 - 10.4319/lo.2011.56.4.1525
DO - 10.4319/lo.2011.56.4.1525
M3 - Article
AN - SCOPUS:84858242133
SN - 0024-3590
VL - 56
SP - 1525
EP - 1535
JO - Limnology and Oceanography
JF - Limnology and Oceanography
IS - 4
ER -