PT - JOURNAL ARTICLE AU - Dragos G. Zaharescu AU - Peter S. Hooda AU - Carmen I. Burghelea AU - Antonio Palanca-Soler TI - A Multiscale Framework for Deconstructing the Ecosystem Physical Template of High-Altitudes Lakes AID - 10.1101/034405 DP - 2016 Jan 01 TA - bioRxiv PG - 034405 4099 - http://biorxiv.org/content/early/2016/06/07/034405.short 4100 - http://biorxiv.org/content/early/2016/06/07/034405.full AB - An ecosystem is generally sustained by a set of integrated physical elements forming a functional landscape unit – ecotope, which supplies nutrients, microclimate, and exchanges matter and energy with the wider environment. To better predict environmental change effects on ecosystems, particularly in critically sensitive regions such as high altitudes, it is imperative to recognise how their natural landscape heterogeneity works at different scales to shape habitats and sustain biotic communities prior to major changes.We conducted a comprehensive survey of catchment physical, geological and ecological properties of 380 high altitude lakes and ponds in the axial Pyrenees at a variety of scales, in order to formulate and test an integrated model encompassing major flows and interactions that drive lake ecosystems.Three composite drivers encompassed most of the variability in lake catchment characteristics. In order of total percentage of variance explained they were: (i) hydrology/hydrodynamics-responsible for type and discharge of inlets/outlets, and for water body size; (ii) bedrock geomorphology, summarizing geology, slope and fractal order-all dictating vegetation cover of catchment slope and lake shore, and the presence of aquatic vegetation; and, (iii) topography, i.e. catchment formation type-driving lakes connectivity, and the presence of summer snow deposits. While driver (i) appeared to be local, (ii) and (iii) showed gradient changes along altitude and latitude. These three drivers differentiated several lake ecotopes based on their landscape similarities. The three-driver model was successfully tested on a riparian vegetation composition dataset, further illustrating the validity and fundamental nature of the concept.The findings inform on the relative contribution of scale-dependent catchment physical elements to lake ecotope and ecosystem formation in high altitude lakes, which should be considered in any assessment of potentially major deleterious effects due to environmental/climate change.Lake Bassia at 2275m a.s.l. in the Pyrenees National Park, France, is one of the millions of remote high altitude lakes worldwide whose catchments are likely to experience severe effects due to climate change. Photo credit: Antonio Palanca-Soler.