Model-Based Assessment of Forest Land Management on Water Dynamics at Various Hydrological Scales – A Case Study

Abstract

This case study follows a straight forward approach to assess forest impact on water dynamics at different scales. Investigation in the catchment of the upper Mulde River (Saxony/Germany) explored firstly to the impact of afforestation measures on the soil hydraulic properties. ‘False chronosequences’ were used to quantify the time-dependent dynamical character of such changes. The findings of these experimental studies were implemented in an existing spatially distributed water budget and rainfall-runoff model (AKWA-M^®) and scaled-up for the 129 km² large catchment of the Schwarze Pockau River (Mulde River). The aim was to describe potentials and limitations of forest impact on water balance and floods at the mesoscale. After that a small catchment (6.8 km²) in the study area was analyzed to describe a socio-economically founded development of the land-use (historical background, site properties, subsidy policy etc.). The objectives were (1) to describe scenarios that reflect a close-to-reality future with different boundary conditions which could be guided by political authorities; (2) to consider climate change especially assessing the site conditions before a flood originating rainfall event.