No abstract

Provenance trials are used to study the effects of tree origin on climate-growth relationships. Thereby, they potentially identify provenances which appear more resilient to anticipated climate change. However, when studying between provenance variability in growth behavior it becomes important to address potential effects related to site marginality in the context of provenance trials. In our study we focus on provenance-specific climate sensitivity manifested under marginal growth conditions. We hypothesized that the provenance effects are masked if trials are located at marginal environmental conditions of the natural species distribution. Under this framework, we investigate 10 Norway spruce provenances growing at two contrasting locations, i.e., a relatively drought-prone site in western Poland (at the climatic margin of Norway spruce’s natural distribution) and a mild and moist site in north-eastern Poland (within its natural range). Combining principal component analysis with climate-growth relationships, we found distinguishable growth patterns and climate correlations among provenances. That is, at the mild and moist north-eastern site, we observed provenance-specific growth patterns and thus a varying drought susceptibility. In contrast, at the dryer western site, provenance-specific growth patterns were less pronounced and all provenances expressed a common and strong sensitivity to drought. Our results indicate that the genetic specificity of growth reactions diminishes toward the distributional margins of a given species. We conclude that the climate conditions at the margins of a species’ distribution are constraining tree growth independently of tree origin. Because of this, the marginality of a site has to be considered when evaluating climate sensitivity of provenances within trials. As a consequence, the yet different responses of provenances to adverse growing conditions may synchronize under more extreme conditions in course of the anticipated climate change.

No abstract

Spatially heterogeneous landscapes provide solutions to the forage‐safety trade‐off when animals can access risky but energetically rewarding patches, or safer but resource‐poor patches. It can be advantageous for an animal to secure access to habitat heterogeneity at a broader scale in order to be able to dynamically adjust finer scale habitat use through time. We tested the hypothesis of a forage‐safety trade‐off optimization tactic in a hunted red deer (Cervus elaphus) population following a large accidental forest fire. We used telemetry data and fitted resource selection functions at the second‐ and third‐order scales. We then integrated the order‐specific probabilities into single, all‐in‐one multi‐level layers that synthetically captured the habitat selection patterns across scales by informing landscape‐scale annual habitat selectivity with finer within‐home‐range seasonal and diel processes. At the landscape scale, red deer anchored their home‐range at the interface of the disturbed and undisturbed patches, thereby securing habitat heterogeneity. This consequently enabled them to modulate within‐home‐range habitat selection depending on the season and the time of the day. In both seasons, red deer consistently used the burnt area for cover more during the day, and foraged in the unburnt forest and open fields at night. Interestingly there were no major seasonal differences in this diel habitat selection patterns. Increased mortality risk during the hunting season did not substantially change their spatial behaviour. We conclude that year‐round avoidance of non‐lethal human disturbance is the main driver of red deer habitat use in this system.

No abstract