Soil conditions required for reaction wood formation of drunken trees in a continuous permafrost region
| Autor: | Akira Osawa, Kazumichi Fujii, Yojiro Matsuura, Koh Yasue |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
010506 paleontology
010504 meteorology & atmospheric sciences thermokarst active layer Permafrost 01 natural sciences Thermokarst lcsh:QH540-549.5 Ecology Evolution Behavior and Systematics lcsh:Environmental sciences 0105 earth and related environmental sciences Earth-Surface Processes lcsh:GE1-350 Global and Planetary Change geography geography.geographical_feature_category frost heaving Frost heaving Drunken trees Black spruce Permafrost Region Active layer gelisols earth hummock Physical geography Tree (set theory) lcsh:Ecology Geology |
| Zdroj: | Arctic, Antarctic, and Alpine Research, Vol 52, Iss 1, Pp 47-59 (2020) |
| ISSN: | 1938-4246 1523-0430 |
| Popis: | Black spruce trees lean to form “drunken” forest on degrading permafrost; however, the causes of tree leaning on continuous permafrost remain unclear. Leaning events are recorded by reaction wood formation in tree rings, and it remains unclear what soil conditions are required for reaction wood formation of drunken trees. Tree disk morphology and soil hummock properties were examined for fifty tree–mound combinations in Northwest Territories, Canada. Spruce trees growing on mound edges form reaction wood on the downslope sides of their trunks. Reaction wood formation in mature trees was greatest in stem tissues between ground level and 30 cm aboveground. Reaction wood formation occurred only in trees growing on mound edges. The extent of reaction wood formation was higher in trees growing in clayey soils than in trees on sandy soils. For trees growing on clayey mound edges, the extent of reaction wood formation decreased with increasing permafrost table depth. Black spruce tree rings formed between ground level and 30 cm aboveground could record movement of clayey soil hummocks over shallow, underlying permafrost tables. A combination of clayey soil texture and shallow permafrost table is likely required for development of hummocks and drunken forests on the continuous permafrost region studied. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|