| Water balance of forest and semi natural areas in Hungary was analyzed using remote-sensing
based evapotranspiration (ET ) maps (1⋅1 km spatial resolution) by CREMAP model over the
2000–2008 period. Recharge (R) was calculated as the difference of precipitation and
evapotranspiration: R = P − ET . For Hungary, the mean annual ET and R in the
percentage of the mean annual precipitation were about 90 percent and 10 percent,
respectively. ET and R were analyzed in the context of land cover types (artificial surfaces,
agricultural areas, forest and semi natural areas, wetlands, water bodies), based on Corine
Land Cover 2006.
As the ET and R maps have 1 km2 while the land cover map has higher resolution, a
number of ET and R pixels would be calculated to more than one land cover types. Thus,
there were selected only the pixels that have 90 percent of their area belong to only
one land cover type (“clear pixels”). For forest and semi natural areas 4424 “clear
pixels” were selected. The ET and R of forest and semi natural areas were analyzed
by regions, in the context of groundwater depth, soil texture and leaf area index
(LAI).
Among the regions, Little Plain (riparian forest ecosystems) presented the highest
ET mean (633 mm), while Southern Transdanubia (mostly sandy areas with good
infiltration capacity) presented the highest R mean (106 mm) for forests. An interesting
phenomenon that, in the case of forests (especially for the Great Plain region), an
increasing ET tendency can be detected with the groundwater depth, down to ten
meters.
This research has been partly supported by the Agroclimate.2 VKSZ_12-1-2013-0034
project. |