Dendrometer measurements of Mediterranean-alpine dwarf shrubs and micro-environmental drivers of plant growth – Dataset from long-term alpine ecosystem research in the Sierra Nevada, Spain (LTAER-ES)

Abstract

Here, we present measurement data of stem diameter variability of three common woody plants, monitored in the Mediterranean-alpine biome for six consecutive years (2015–2020). These focal species (Astragalus granatensis, Cytisus galianoi, and Genista versicolor) are abundant across the Sierra Nevada mountain chain (Southern Spain) and will potentially be affected by severe future climatic changes predicted for the region, including increased aridification in a warming environment. Understanding their fine-scale radial growth-patterns in relation to local environmental parameters might gain further insights into future vegetational shifts. We therefore used 139 high-resolution dendrometers to continuously monitor specimens along a steep elevational gradient and at varying topographical positions within the heterogeneous topography of the region. Additionally, we measured on-site environmental conditions at each studied site, including soil moisture and soil temperature within the root zone. All data were recorded at hourly resolution and are presented as daily mean values. The dataset was collected as a part of our long-term alpine ecosystem research program (LTAER), which functions as the basis for our recent projects on the use of dendrometer data to better understand the physiological mechanisms and the environmental drivers of the ongoing alpine greening.

Alpine shrub growth follows bimodal seasonal patterns across biomes – unexpected environmental controls

“…VPD reflects the combined effect of temperatures and air humidity, and is known to directly affect plant water use through transpiration, and productivity 51 . All data, including dendrometer as well as environmental measurements are available in separate publications 61 , 62 .…”

Patterns, timing, and environmental drivers of growth in two coexisting green‐stemmed Mediterranean alpine shrubs species

“…Cytisus galianoi shows a relatively wide biogeographical and ecophysiological range, occurring at elevations up to 2700 m above sea level (asl) at a variety of sites ranging from exposed ridges with severe frosts during winter to early snowbeds. Genista versicolor diminishes with elevation (Lorite, 2001) and is restricted to the more protected early snowbeds and slopes (Löffler et al ., 2022). Both species presumably create their own microhabitat (Pistón et al ., 2016).…”

“…1). Here, our focal species dominate the vegetation cover and coexist at the middle‐alpine slopes (Löffler et al ., 2022). The overall climate is characterized by a stable high‐pressure inversion layer in summer with autochthonous weather associated with continental easterly currents, resulting in hot and dry conditions (Roberts et al ., 2011; Jiménez‐Moreno & Anderson, 2012).…”

“…Here, we aimed at a better understanding of alpine shrub growth in the Mediterranean by monitoring growth patterns in two coexisting green‐stemmed species with similar traits but contrasting biogeographic patterns, coexisting on slope sites only (Löffler et al ., 2022). According to the general assumption that species with common traits exhibit similar growth strategies (Westoby et al ., 2002), we expected to find (a) congruencies in intra‐ and interannual growth patterns, (b) synchronicity of growth timing, and (c) similar environmental drivers of growth, despite differences in their biogeographical patterns.…”

Patterns, timing, and environmental drivers of secondary growth in two physiologically distinct Mediterranean alpine shrub species

“…C. galianoi disappears from the latest snow beds, whereas A. granatensis dominates the hilltops at about 2800 m a.s.l. (Löffler et al 2022).…”