GIS ANALYSIS OF SHORT AND LONG TERM HYDROGEOGRAPHICAL CHANGES ON A NATURE CONSERVATION AREA AFFECTED BY ARIDIFICATION - Carpathian Journal of Earth And Environmental Sciences

The shrinking of wetlands in Hungary is a striking consequence of recent climatic processesand anthropogenic influence. The investigation of endangered wetland areas is of crucial importance,since the complex phenomenon of climate change superimposed by inadequate management strategies seriouslythreatens these exceptionally rich and diverse areas. Statistical and spatial assessment is a difficulttask as tendencies need to be realised and quantified in a highly variable environment. The quantity ofwater in the landscape is a key factor from this aspect. The database of the study was made up of mediumscale and freely accessible LANDSAT satellite images at the greatest possible temporal resolution. Themain object of the investigation was the mapping of aridification on a longer 130 year and a shorter 4 yeartimescale at the protected Upper Kiskunság Lakes, being severely hit by droughts in the past decades.When analysing maps and images certain areas were difficult to classify and results did hardly yield ageneral and uniform long term tendency. Degradation processes were evaluated by applying both an optimisticand pessimistic scenario. In case of the optimistic evaluation, ambiguous patches were alwaysconsidered to represent the favourable state in the future (the pessimistic approach worked the oppositeway). Concerning the optimistic and pessimistic scenarios 5.6 and 33.5% of the study area will be affectednegatively by water management strategies and precipitation decrease, respectively. As a consequencea remote sensing based monitoring activity is suggested by using sensors of great resolution in order tosupport planning, decision making and nature conservation in the future.