| Popis: |
The term ‘natural protective effect’ is commonly associated with the capacity of ecosystems to balance or buffer the action of natural hazard processes, such as floods, droughts, snow avalanches, mass-movements or soil erosion (Gray and Leiser 1982; Stocklin et al. 2007; Wehrli et al. 2007; Salzman et al. 2001; Stoffel 2006; Nairz et al. 2015). They are generated by certain elements in mountain catchments: the topography, soils, vegetation cover and forests, and waterbodies. Protective effects in ecosystems are inseparably linked with the emergence and impact of the hazard processes themselves and often originate from the same ecosystem elements. While in the normal case, natural forces driving or buffering hazard processes are well balanced in mountain catchments, excessive natural events (e.g. extreme precipitation, thick snow cover, strong earthquakes) may severely unbalance the ecosystems and trigger natural catastrophic events. However, antagonistic natural effects in ecosystems exist, that counterbalance the emergence, displacement and action (impact) of hazard processes (Rudolf-Miklau et al. 2012). Natural protective effects emerge and subsist by nature, respectively without human creative act. They are bounded in their capacity of protection, either seasonally or when reaching a critical threshold. As a rule, the sustainability of natural protective effects requires a certain treatment or maintenance of the ecosystem. |
