## 5 Conclusions  
In this paper we present analysis of impact of short- to medium-term meteorological drought on the alpine mountain forest of South Tyrol. The study provides temporal and spatial identification of drought induced changes, additionally exploring phenology and green biomass production variability within the affected forest ecosystem. Our results indicate complex and non-uniform drought impact within the region, where forest response to aridity and elevated temperature is principally governed by location, local environmental conditions and forest structure. Identified meteorological variability highlighted mild to extreme drought conditions between 2003 and 2007, as well as increasing aridity of the local climate. Both patterns are in good accordance with other studies. Despite considerably arid meteorological conditions in the region, decline in status of the alpine mountain forest was only localized. Furthermore, phenological activity and biomass production of some stands enhanced along with drought development. Elevation was recognized to have the leading role in shaping forest response to drought. A distinction between stands growing below and above 1400 m a.s.l. was made, where the latter showed productivity increment in response to temperature increase in 2003. Aspect-specific differences in forest drought response were more entangled and largely dependent on considered drought evolution pattern. Although forest type was expected to have the greatest effect on forest phenology and green biomass production during aridity conditions, insufficient representation of broadleaved and mixed stands hindered analyses. Since inclination showed vague relation to forest status, we put into question aptness of analyzing this factor at 250 m resolution. Perceived changes in forest phenology and green biomass production were coincided with other studies on drought response in the alpine ecosystem. The results accentuate different vegetation related information fostered in the NDVI and NDII7 time series. While forest foliage water content approximated by NDII7 better followed apparent meteorological conditions, trees photosynthetic activity assessed through NDVI, stronger related to more subtle patterns. The diverse focus of both indices suggests their further synergetic use for comprehensive analysis of forest ecological dynamics. Despite complexity of the area, our analysis provided valuable insight into forest growth diversity under drought conditions. Although some identified tendencies support climate change projections and vegetation transformation trends [12], our results are in itself a no solid evidence for alternation of the local climate, and arising vegetation response. Further analyses should be carried out in order to answer this burning question. We believe our study sheds a new light on the critical aspect of drought impact on ecological dynamics within complex alpine forest. Prospective synergy with additional datasets, including CO\({}_{2}\) fluxes and local dendrochronological analyses; an extensive inspection of mutual combination of factors and factors' classes, as well as an extension of available time series combined with downscalingof NDVI and NDII7 datasets, will significantly enhance our understanding of forest growth under stress and allow to further improve climate-change modeling and carbon-sink efficiency analyses. **Supplementary Materials:** The following are available online at www.mdpi.com/1999-4907/9/2/91/s1. Table S1: Number of forest pixels that underwent linear interpolation within the 2001-2013 MODIS derived NDVI time series. Complete forest mask comprises 52394 pixels; Table S2: Number of forest pixels that underwent linear interpolation within the 2001-2013 MODIS derived NDII7 time series. Complete forest mask comprises 52,394 pixels.