Effects of mild drought on the morphology of sun and shade needles in 20-year-old Norway spruce trees
| Autor: | Toril D. Eldhuset, Josef Urban, D. Volarík, Isabella Børja, Nina Elisabeth Nagy, Paal Krokene, Roman Gebauer |
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| Jazyk: | angličtina |
| Rok vydání: | 2019 |
| Předmět: |
0106 biological sciences
Ecophysiology Canopy Canopy Position Morphology (linguistics) Crown Light Gradient 01 natural sciences Transpiration Dry weight Needle Structure lcsh:Forestry Nature and Landscape Conservation Ecology biology Drought VDP::Landbruks- og Fiskerifag: 900 Picea abies fungi food and beverages Forestry 04 agricultural and veterinary sciences biology.organism_classification Water potential Agronomy Productivity (ecology) 040103 agronomy & agriculture lcsh:SD1-669.5 0401 agriculture forestry and fisheries 010606 plant biology & botany |
| Zdroj: | iForest : Biogeosciences and Forestry iForest-Biogeosciences and Forestry, Vol 12, Iss 1, Pp 27-34 (2019) |
| Popis: | Several studies have looked at how individual environmental factors influence needle morphology in conifer trees, but interacting effects between drought and canopy position have received little attention. In this study, we characterized morphological responses to experimentally induced drought stress in sun exposed and shaded current-year Norway spruce needles. In the drought plot trees were suffering mild drought stress, with an average soil water potential at 50 cm depth of -0.4 MPa. In general, morphological needle traits had greater values in sun needles in the upper canopy than in shaded needles in the lower canopy. Needle morphology 15 months after the onset of drought was determined by canopy position, as only sun needle morphology was affected by drought. Thus, canopy position was a stronger morphogenic factor determining needle structure than was water availability. The largest influence of mild drought was observed for needle length, projected needle area and total needle area, which all were reduced by ~27% relative to control trees. Needle thickness and needle width showed contrasting sensitivity to drought, as drought only affected needle thickness (10% reduction). Needle dry mass, leaf mass per area and needle density were not affected 15 months after the onset of mild drought. Our results highlight the importance of considering canopy position as well as water availability when comparing needle structure or function between conifer species. More knowledge about how different canopy parts of Norway spruce adapt to drought is important to understand forest productivity under changing environmental conditions. |
| Databáze: | OpenAIRE |
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