Deposition, burial and sequestration of carbon in an oligotrophic, tropical lake
Por:
Alcocer, J, Ruiz-Fernandez, AC, Escobar, E, Perez-Bernal, LH, Oseguera, LA, Ardiles-Gloria, V
Publicada:
1 ene 2014
Resumen:
The amount of biogenic carbon that may be deposited, buried and
eventually preserved (sequestered) in the sediments of a tropical,
oligotrophic lake, was evaluated based on i) the temporal variation of
the particulate organic carbon (POC) concentration in the superficial
sediments in the deep zone of Lake Alchichica, Puebla, Mexico; and ii)
the POC accumulation and preservation in a Pb-210-dated sediment core
from the lake. In Lake Alchichica the POC concentration in the surficial
sediments ranged between 12 and 60 mg POC g(-1) (25 +/- 12 mg POC g(-1)
dry weight). The magnitude of the sedimented POC in Alchichica was high
and mostly of autochthonous origin. The POC concentrations recorded in
the sediment core (16.6 to 31.6 mg g(-1) dry weight) were comparable to
the concentration range observed in the surface sediment samples
collected during the study period, which signaled a high POC
preservation capacity in the sedimentary column of Lake Alchichica. The
POC fluxes, estimated from the Pb-210-dated sediment core, varied
between 14.9 and 35.3 g m(-2) year(-1) within the past century; and the
maximum POC losses through diagenesis during this period were estimated
to be lower than 25%. This study concludes that deep tropical lakes,
exemplified by Lake Alchichica, accumulate and preserve most of the POC
deposited, playing an important role in regional carbon balances.
Filiaciones:
Alcocer, J:
Univ Nacl Autonoma Mexico, Fac Estudios Super Iztacala, Proyecto Invest Limnol Trop, Tlalnepantla 54090, Estado De Mexic, Mexico
Ruiz-Fernandez, AC:
Univ Nacl Autonoma Mexico, Inst Ciencias Mar & Limnol, Unidad Acad Mazatlan, Mazatlan 82040, Sin, Mexico
Escobar, E:
Univ Nacl Autonoma Mexico, Inst Ciencias Mar & Limnol, Lab Biodiversidad & Macroecol, Mexico City 04510, DF, Mexico
Perez-Bernal, LH:
Univ Nacl Autonoma Mexico, Inst Ciencias Mar & Limnol, Unidad Acad Mazatlan, Mazatlan 82040, Sin, Mexico
Oseguera, LA:
Univ Nacl Autonoma Mexico, Fac Estudios Super Iztacala, Proyecto Invest Limnol Trop, Tlalnepantla 54090, Estado De Mexic, Mexico
Ardiles-Gloria, V:
Univ Nacl Autonoma Mexico, Fac Estudios Super Iztacala, Proyecto Invest Limnol Trop, Tlalnepantla 54090, Estado De Mexic, Mexico
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