A global analysis of recent disturbance patterns in temperate forest ecosystems

SOMMERFELD, A; SENF, C; SEIDL, R; GLOBAL DISTURBANCE PATTERNS CONSORTIUM; PARITSIS, J

Freiburg

Congreso; IUFRO 125th Anniversary Congress 2017; 2017

UFRO

Abstract: Natural disturbances in temperate forest ecosystems are expected to change drastically within the 21th century, yet the patterns anddrivers of disturbances remain incompletely understood. To better understand disturbances and provide a baseline for future disturbance change,it is important to quantify recent disturbances and their within-biome variation. Until recently, however, such large-scale analyses were limited bya widely varying availability and quality of disturbance data. In recent years, much progress has been made in the remote sensing of forestchange. Yet, anthropogenic and natural disturbances cannot be distinguished in currently available datasets, limiting their ecologicalinterpretation. To overcome this limitation and consistently contrast the patterns of natural disturbances with those in coupled human and naturalsystems, we - together with a consortium of global disturbance experts (see http://resin.boku.ac.at/page/global-disturbance-patterns) - focused on52 strictly protected areas in the temperate forest biome, distributed across five continents and representing a total area of ~6,450 000 ha. Ourobjectives were to quantitatively describe recent disturbance patterns (e.g. occurrence, size, and shape), identify factors explaining within-biomevariation in disturbance, and contrast this variation with the differences between protected areas and their managed surroundings. Our resultsindicate that differences in the locally prevailing disturbance agents are important for explaining variable disturbance patterns across the globe.We found that host-specific disturbance agents such as insects and pathogens create significantly more complex spatial patterns thandisturbances affecting all trees. Additionally, topographic complexity and climatic extremes affected disturbance occurrence. While disturbanceregimes differed within and outside protected areas, the large-scale differences across the biome were more pronounced than managementeffects.