Black spruce (Picea mariana) is the most abundant tree species in the boreal biome, but little is known about how climate warming may change recruitment in peatlands, especially those affected by permafrost thaw. We used results from a seven-year study in northern Manitoba, Canada, to address the following questions: (1) What is the relative importance of early life history transitions on P. ma...

Responses of wetland carbon cycling to environmental changes, particularly changes in water table depth, which are the key determinants to control the ecological and biogeochemical functions of wetlands, are highly non-linear and complex due to the dynamic interactions of several physical and biological processes. Several field experiments have found that wetland productivities have a significa...

In this study we investigate the effect of a water table boundary on solute spreading during infiltration in the vadose zone of heterogeneous soils. It has been found recently that the presence of the water table significantly affects unsaturated flow in a heterogeneous vadose zone and causes the flow to be spatially nonstationary. Because a vadose zone is by definition bounded by the water tab...

Plants, by influencing water fluxes across the ecosystem–vadose zone–aquifer continuum, can leave an imprint on salt accumulation and distribution patterns. We explored how the conversion of native grasslands to oak plantations affected the abundance and distribution of salts on soils and groundwater through changes in the water balance in naturally salt-affected landscapes of Hortobagy (Hungar...

The occurrence of halogenated volatile organic compounds (HVOCs) in groundwater beneath several municipal solid waste landfills in Tucson, Arizona in the absence of significant liquid phase movement has suggested that vapor phase transport may be the principal process transporting HVOCs from the vadose zone into the water table. The results of mathematical modeling of these transport processes ...

Groundwater irrigation has been instrumental in enhancing food security and, arguably, in mitigating poverty in developing countries. Groundwater provides timely irrigation, leading to an increase in crop intensity and productivity (Food and Agriculture Organization 2003). But groundwater irrigation also contributes the most to the depletion of groundwater reserves. Countries with significant g...

The lowering of the groundwater table causes the area above the water table to become unsaturated and capillary phenomena to appear in this zone. This means that the bearing capacity of shallow footings will be influenced by capillary stress or matric suction. In this research, the effect of groundwater table lowering on the bearing capacity of a shallow square model footing on dense sand has b...