Riparian zones in semi-arid regions often exhibit high rates of evapotranspiration (ET) in spite of low soil moisture content due to vegetation that is able to withdraw water from shallow aquifers. This work better defines the relationship between ET and the saturated zone by comparing the observed water table drawdown to analytically modeled drawdown in fully penetrating wells of an unconfined...

Water-table drawdown across peatlands increases carbon dioxide (CO2) and reduces methane (CH4) emissions. The net climatic effect remains unclear. Based on global observations from 130 sites, we found a positive (warming) climate of water-table drawdown. Using machine-learning-based upscaling approach, predict that peatland driven by drying human activities will increase CO2 emissions 1.13 (95%...

[1] Growing season CH4 fluxes were monitored over a two year period following the start of ecosystem-scale manipulations of water table position and surface soil temperatures in a moderate rich fen in interior Alaska. The largest CH4 fluxes occurred in plots that received both flooding (raised water table position) and soil warming, while the lowest fluxes occurred in unwarmed plots in the lowe...

it is over two decades that groundwater flow models are routinely implemented for better management of groundwater resources.modeling groundwater flow with the help of the ground water modeling system (gms) in the damghan plain aquifer in northern iran,which experiences declining levels and numerous environmental hazards, has demonstrated that, (a) in the worst case scenario theaquifer will fac...

A semianalytical solution is presented for transient streaming potentials associated with flow to a pumping well in an unconfined aquifer, taking into account the effect of flow in the unsaturated zone above the water table. Flow in the unsaturated zone is modeled with a linearized form of Richards’ equation using an exponential model for soil moisture retention and unsaturated hydraulic conduc...

global warming, as a consequence of greenhouse gases accumulation, has exerted significant impacts on biosphere. methane, a product of reduction processes of organic carbon in anaerobic conditions, is mainly emitted from paddy fields. the aim followed in this research is to evaluate the impact of midseason drainage on methane emission from paddy fields. the research was conducted with three tre...