Intensifying neighbouring tree competition suppresses tree growth at the eastern Tibetan tree line

Functional Ecology, Год журнала: 2025, Номер unknown

Опубликована: Апрель 7, 2025

Abstract Although neighbourhood interactions are important for the establishment and survival of tree line trees, it remains poorly understood how they affect growth rates under changing climatic conditions. Here, we combine census data dendrochronological measurements from 18 plots between 4300 4520 m asl on eastern Tibetan Plateau to develop a retrospective Neighbourhood Index. We then investigate whether interaction is facilitative or competitive changes over time. Our results show that competition water not only dominates Plateau, but also increased significantly 1960 2009 ( p < 0.001). Contrary common belief at high elevation, demonstrate among mature trees in ecotones likely increase projected global warming. Read free Plain Language Summary this article Journal blog.

Язык: Английский

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Late Quaternary fluctuation in upper range limit of trees shapes endemic flora diversity on the Tibetan Plateau

Nature Communications, Год журнала: 2025, Номер 16(1)

Опубликована: Фев. 20, 2025

The influence of paleoclimate in shaping current biodiversity pattern is widely acknowledged. However, it remains unclear how the upper paleo-range limit trees, which dictated habitat endemic alpine species, affects variability species composition across space over Tibetan Plateau. We integrated satellite-derived range dendrochronological data, and fossil pollen records with a dataset climate-driven predictive model to reconstruct spatio-temporal trees at 100-year intervals since Last Glacial Maximum. Our results show that distributed lowest elevations during Maximum (~3426 m), ascended highest Holocene Climatic Optimum (~4187 level ~180 m higher than present-day (~4009 m). temporal fluctuations limits play more important role spatial beta-diversity flora, regions witnessing having lower beta-diversity. therefore suggest anthropogenic-caused climate change on decadal-to-centennial timescales could lead orbitally-forced centennial-to-millennium timescales, consequently cause homogenization composition, threatening pool.

Язык: Английский

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Climatic Influence on Growth Performance of Abies spectabilis in the Himalayas

Forests, Год журнала: 2025, Номер 16(3), С. 473 - 473

Опубликована: Март 8, 2025

Climate change has affected forest ecosystems across the world over past century. However, its impact is particularly high in Himalayas due to increasing temperatures, extreme precipitation events, and regional droughts. In this context, a review of current stage research was deemed necessary understand adaptation key conifer species climate variability Central Himalayas. Hence, we conducted systematic published peer-reviewed journal articles addressing growth performance Abies spectabilis (D. Don) Spach From review, three main patterns response have emerged: positive correlation radial tree with temperature previous growing seasons, limitation by winter temperature, or moisture pre-monsoon season. Overall, results indicate an elevation-dependent sensitivity, crucial role availability, seasonal shifts climate–growth relationships, reflecting species’ adaptability changing conditions. Our revealed that studies on wood anatomical traits A. are still rare. The tree-ring shows complex variability, as well decreasing trends distribution range.

Язык: Английский

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Sub-surface processes and heat fluxes at coarse blocky Murtèl rock glacier (Engadine, eastern Swiss Alps): seasonal ice and convective cooling render rock glaciers climate-robust

Earth Surface Dynamics, Год журнала: 2025, Номер 13(3), С. 365 - 401

Опубликована: Май 15, 2025

Abstract. We measured sub-surface heat fluxes and calculated the energy budget of coarse blocky active layer (AL) Murtèl rock glacier, a seasonally snow-covered permafrost landform located in eastern Swiss Alps. In highly permeable AL, conductive/diffusive transfer, including thermal radiation, non-conductive transfer by air circulation (convection), storage changes from seasonal build-up melting ground ice, shapes regime. Individual are quantified based on novel situ sensor array AL (operational 2020–2023) direct observations ice melt (in thaw seasons 2022–2024). The yields first field-data-based quantitative estimate climate sensitivity glaciers. total uptake during season has been increasing 4–10 MJ m−2 per decade (4 %–11 % 2022 94 m−2), driven earlier snow melt-out June increasingly hot dry July–September periods. Two thaw-season processes render glacier comparatively climate-robust. First, intercepts ∼70 (55–85 m−2) flux that runs off as meltwater, ∼20 (10–20 is spent heating blocks, only ∼10 (7–13 transferred into body beneath causes slow degradation. Second, effective conductivity ventilated increases 1.2Wm-1K-1 under strongly stable temperature gradients (weak warming) to episodically over 10Wm-1K-1 unstable (strong cooling), favouring convective cooling buoyancy-driven Rayleigh ventilation (thermal semiconductor effect). winter, radiatively cooled infiltrating through discontinuous, semi-closed cover leads strong cooling. two characteristic parameters (effective intrinsic permeability) sensitive debris texture; hence undercooling specific material.

Язык: Английский

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The global spectrum of tree crown architecture

Nature Communications, Год журнала: 2025, Номер 16(1)

Опубликована: Май 26, 2025

Язык: Английский

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