Delineating sources of groundwater recharge and carbon in Holocene aquifers of the central Gangetic basin using stable isotopic signatures.
Isotopes Environ Health Stud
; 55(3): 254-271, 2019 Jun.
Article
en En
| MEDLINE
| ID: mdl-31012329
ABSTRACT
Stable isotopes of water (δ2H, δ18O) and δ13CTIC were used as a tool to trace the recharge processes, natural carbon (organic and inorganic) source and dynamics in the aquifers of the central Gangetic basin, India. Stable isotope (δ2H, δ18O) record of groundwater (n = 105) revealed that the groundwater of Piedmont was recharged by meteoric origin before evaporation, while aquifers of the older and younger alluvium were recharged by water that had undergone evaporation loss. River Ganges and its tributaries passing through this area have very little contribution in recharging while ponds play no role in the recharging of adjacent aquifers. The connectivity of shallow aquifers of aquitard formation (comprised of clay/sandy clay with thin patches of fine grey sand), i.e. 25-60â
m below ground level (bgl) with the main upper aquifer (at a depth of >120â
mâ
bgl) was found to be higher in older and younger alluvium. Negative values of δ13CTIC (median -9.6 ; range -13.2 to -5.4 ) and high TIC (median 35â
mM; range 31-46â
mM) coupled with low TOC (median 1.35â
mg/L; range 0.99-1.77â
mg/L) indicated acceleration in microbial activity in the younger alluvium, especially in the active floodplain of river Ganges and its proximity.
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Bases de datos:
MEDLINE
Asunto principal:
Isótopos de Oxígeno
/
Agua Subterránea
/
Isótopos de Carbono
/
Deuterio
País/Región como asunto:
Asia
Idioma:
En
Revista:
Isotopes Environ Health Stud
Asunto de la revista:
SAUDE AMBIENTAL
Año:
2019
Tipo del documento:
Article
País de afiliación:
India