GGR309H5 Lecture Notes - Lecture 5: Evapotranspiration, Okefenokee Swamp
Document Summary
Hydroperiod year-to-year variability: spring water level > fall water level. Due to snow melt: rarely the same for each year (graph 1, rarely the same in similar wetlands (graph 2, generally, water level is not stable. Seasonally, daily, semi-daily, yearly: management seeks to minimize the fluctuation in water levels. Fluctuation needs to be maintained or entire system will start to suffer in the long run: needs variable/fluctuating hydroperiod. Hydroperiod is the result of: the balance between the in"s and out"s, surface contours of the landscape, subsurface soil, geology, & groundwater conditions. Wetland water balance: the accountancy of the water at a site, in"s out"s = change in storage. Precipitation (pin) + surface water (swin) + groundwater (gwin) . Evapotranspiration (etout) surface water (swout) groundwater (gwout) +/- tides (t) ] = change in storage. Change in storage = change in volume (v) / change in time (t) Water balance examples: okefenokee swamp, georgia.
