Results 41 to 50 of about 54,771 (221)
Branch-depth: Generalizing tree-depth of graphs [PDF]
European J. Combin., 90(December 2020), 103186, 2019 We present a concept called the branch-depth of a connectivity function, that generalizes the tree-depth of graphs. Then we prove two theorems showing that this concept aligns closely with the notions of tree-depth and shrub-depth of graphs as follows.
arxiv +1 more source
Dwarf shrubs as bioindicators. [PDF]
Silva Fennica, 1981 Several studies of air polluted forest environments have shown that dwarf shrubs suffer from air pollution. In many cases the disturbances have been attributed to the susceptibility of the dwarf shrubs, while in some cases the vegetational competition factor has been discussed.
Hilkka Mikkonen, Satu Huttunen
openaire +3 more sources
Arctic shrubification mediates the impacts of warming climate on changes to tundra vegetation
Environmental Research Letters, 2016 Climate change has been observed to expand distributions of woody plants in many areas of arctic and alpine environments—a phenomenon called shrubification.
Heidi K Mod, Miska Luoto
doaj +1 more source
Ecology and Evolution, 2020 Periodic climatic oscillations and species dispersal during the postglacial period are two important causes of plant assemblage and distribution on the Qinghai‐Tibet Plateau (QTP).
Yuanming Xiao +6 more
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Pseudo-finiteness of arbitrary graphs of bounded shrub-depth [PDF]
arXiv, 2022 We consider classes of arbitrary (finite or infinite) graphs of bounded shrub-depth, specifically the classes $\mathrm{TM}_r(d)$ of arbitrary graphs that have tree models of height $d$ and $r$ labels. We show that the graphs of $\mathrm{TM}_r(d)$ are $\mathrm{MSO}$-pseudo-finite relative to the class $\mathrm{TM}^{\text{f}}_r(d)$ of finite graphs of ...
arxiv
Shrub tundra ecohydrology: rainfall interception is a major component of the water balance
Environmental Research Letters, 2019 As shrubs expand across the Arctic, they alter all cycles in the Earth system, including the water cycle. However, the coupling of shrubs with the water cycle during summer remains poorly understood.
Simon Zwieback +3 more
doaj +1 more source
Drivers of soil temperature variation in alpine lichen heaths and shrub vegetation during the summer
Arctic, Antarctic, and Alpine Research, 2023 Lichen heaths are decreasing in abundance in alpine and Arctic areas because of an increased competition with shrubs. This shift in vegetation might have important consequences for the soil temperature. The aim of this study is to find the drivers of the
Peter Aartsma +3 more
doaj +1 more source
LandBirds, potential pollinators and bio-indicators of ecosystem health, are important components of the global ecosystems. Habitat degradation and anthropogenic disturbance have influenced their survival.
Gayatri Mahanta +2 more
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Some classical model theoretic aspects of bounded shrub-depth classes [PDF]
arXiv, 2020 We consider classes of arbitrary (finite or infinite) graphs of bounded shrub-depth, specifically the class $\mathrm{TM}_{r, p}(d)$ of $p$-labeled arbitrary graphs whose underlying unlabeled graphs have tree models of height $d$ and $r$ labels. We show that this class satisfies an extension of the classical L\"owenheim-Skolem property into the finite ...
arxiv
Kernelizing MSO Properties of Trees of Fixed Height, and Some Consequences [PDF]
Logical Methods in Computer Science, Volume 11, Issue 1 (April 1,
2015) lmcs:748, 2012 Fix an integer h>=1. In the universe of coloured trees of height at most h, we prove that for any graph decision problem defined by an MSO formula with r quantifiers, there exists a set of kernels, each of size bounded by an elementary function of r and the number of colours. This yields two noteworthy consequences.
arxiv +1 more source