A common soil temperature threshold for the upper limit of alpine grasslands in European mountains

AbstractWhile climatic research about treeline has a long history, the climatic conditions corresponding to the upper limit of closed alpine grasslands remain poorly understood. Here, we propose a climatic definition for this limit, the ‘grassline’, in analogy to the treeline, which is based on the growing season length and the soil temperature. Eighty-seven mountain summits across ten European mountain ranges, covering three biomes (boreal, temperate, Mediterranean), were inventoried as part of the GLORIA project. Vascular plant cover was estimated visually in 326 plots of 1 × 1 m. Soil temperatures were measured in situ for 2–7 years, from which the length of the growing season and mean temperature were derived. The climatic conditions corresponding to 40% plant cover were defined as the thresholds for alpine grassland. Closed vegetation was present in locations with a mean growing season soil temperature warmer than 4.9 °C, or a minimal growing season length of 85 days, with the growing season defined as encompassing days with daily mean ≥ 1 °C. Hence, the upper limit of closed grasslands was associated with a mean soil temperature close to that previously observed at the treeline, and in accordance with physiological thresholds to growth in vascular plants. In contrast to trees, whose canopy temperature is coupled with air temperature, small-stature alpine plants benefit from the soil warmed by solar radiation and consequently, they can grow at higher elevations. Since substrate stability is necessary for grasslands to occur at their climatic limit, the grassline rarely appears as a distinct linear feature.

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Nutrient cycling in Alaskan tundra in response to experimental manipulation of growing season length and soil temperature : a climate change scenario

10.25148/etd.fi13101545 ◽

2003 ◽

Author(s):

Lorraine E. Ahlquist

Keyword(s):

Climate Change ◽

Nutrient Cycling ◽

Soil Temperature ◽

Climate Change Scenario ◽

Growing Season ◽

Experimental Manipulation ◽

Change Scenario ◽

Season Length ◽

Growing Season Length ◽

Alaskan Tundra

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Growing Season Precipitation Rather than Growing Season Length Predominates Maximum Normalized Difference Vegetation Index in Alpine Grasslands on the Tibetan Plateau

Sustainability ◽

10.3390/su12030968 ◽

2020 ◽

Vol 12 (3) ◽

pp. 968

Author(s):

Jiang Wei Wang ◽

Meng Li ◽

Guang Yu Zhang ◽

Hao Rui Zhang ◽

Cheng Qun Yu

Keyword(s):

Tibetan Plateau ◽

Vegetation Index ◽

Normalized Difference Vegetation Index ◽

Growing Season ◽

The Tibetan Plateau ◽

Season Length ◽

Alpine Grasslands ◽

Vegetation Productivity ◽

Growing Season Length ◽

Growing Season Precipitation

Precipitation and growing season length (GSL) are vital abiotic and biotic variables in controlling vegetation productivity in alpine regions. However, their relative effects on vegetation productivity have not been fully understood. In this study, we examined the responses of the maximum normalized difference vegetation index (NDVImax) to growing season precipitation (GSP) and GSL from 2000 to 2013 in 36 alpine grassland sites on the Tibetan Plateau. Our results indicated that NDVImax showed a positive relationship with prolonged GSL (R2 = 0.12) and GSP (R2 = 0.39). The linear slope of NDVImax increased with that of GSP rather than GSL. Therefore, GSP had a stronger effect on NDVImax than did GSL in alpine grasslands on the Tibetan Plateau.

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Consistent Poplar Clone Ranking Based on Leaf Phenology and Temperature Along a Latitudinal and Climatic Gradient in Northern Europe

BioEnergy Research ◽

10.1007/s12155-021-10249-5 ◽

2021 ◽

Author(s):

Giulia Vico ◽

Almir Karacic ◽

Anneli Adler ◽

Thomas Richards ◽

Martin Weih

Keyword(s):

Growing Season ◽

Climatic Conditions ◽

Northern Europe ◽

Season Length ◽

Spring Phenology ◽

Phenological Data ◽

Growing Season Length ◽

Degree Day ◽

Growing Conditions ◽

The Baltic

AbstractIn Northern Europe, poplars (Populus) can provide biomass for energy and material use, but most available clones were developed for lower latitudes and are unlikely to be well adapted to higher latitudes, even under warmer climates. We thus need to understand how clones respond to climatic conditions and photoperiod, and how these responses can be predicted. We answer these questions exploiting leaf phenological data of Populus clones, grown in six sites across the Baltic region, in Northern Europe, for 2 years with contrasting climatic conditions. Regarding the effects of climatic conditions and photoperiod, within each site, higher temperatures advanced the timing and enhanced the speed of spring and autumn phenology, but reduced the effective growing season length. Across sites, latitude affected the timing of spring and autumn phenology, the speed of spring phenology, and the effective growing season length; clone affected only the timing of phenology. Regarding the predictability of clone response to growing conditions, the growing degree day (GDD) model could not predict spring phenology, because the growing degree day threshold for a specific phenological stage was not only clone-, but also latitude- and year-specific. Yet, this GDD threshold allowed a robust ranking of clones across sites and years, thus providing a tool to determine the relative differences across clones, independently of latitude and temperature. A similar, but not as strong, pattern was observed in the timing of spring and autumn phenological stages. Hence, while prediction of spring phenology remains elusive, the ranking of clones based on observations of their phenology in a single location can provide useful indications on the clones’ relative performance under different latitudes and climates.

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Growing‐season length and soil microbes influence the performance of a generalist bunchgrass beyond its current range

Ecology ◽

10.1002/ecy.3095 ◽

2020 ◽

Vol 101 (9) ◽

Author(s):

Clifton P. Bueno de Mesquita ◽

Samuel A. Sartwell ◽

Steven K. Schmidt ◽

Katharine N. Suding

Keyword(s):

Soil Microbes ◽

Growing Season ◽

Season Length ◽

Current Range ◽

Growing Season Length

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Growing Season Length as a Key Factor of Cumulative Net Ecosystem Exchange Over the Pine Forest Ecosystems in Europe

International Agrophysics ◽

10.1515/intag-2015-0026 ◽

2015 ◽

Vol 29 (2) ◽

pp. 129-135 ◽

Cited By ~ 3

Author(s):

Alina Danielewska ◽

Marek Urbaniak ◽

Janusz Olejnik

Keyword(s):

Air Temperature ◽

Measurement Data ◽

Growing Season ◽

Pine Forest ◽

Pine Forests ◽

Net Ecosystem Productivity ◽

Ecosystem Productivity ◽

Season Length ◽

Important Species ◽

Growing Season Length

Abstract The Scots pine is one of the most important species in European and Asian forests. Due to a widespread occurrence of pine forests, their significance in the energy and mass exchange between the Earth surface and the atmosphere is also important, particularly in the context of climate change and greenhouse gases balance. The aim of this work is to present the relationship between the average annual net ecosystem productivity and growing season length, latitude and air temperature (tay) over Europe. Therefore, CO2 flux measurement data from eight European pine dominated forests were used. The observations suggest that there is a correlation between the intensity of CO2 uptake or emission by a forest stand and the above mentioned parameters. Based on the obtained results, all of the selected pine forest stands were CO2 sinks, except a site in northern Finland. The carbon dioxide uptake increased proportionally with the increase of growing season length (9.212 g C m-2 y-1 per day of growing season, R2 = 0.53, p = 0.0399). This dependency showed stronger correlation and higher statistical significance than both relationships between annual net ecosystem productivity and air temperature (R2 = 0.39, p = 0.096) and annual net ecosystem productivity and latitude (R2 = 0.47, p = 0.058). The CO2 emission surpassed assimilation in winter, early spring and late autumn. Moreover, the appearance of late, cold spring and early winter, reduced annual net ecosystem productivity. Therefore, the growing season length can be considered as one of the main factor affecting the annual carbon budget of pine forests.

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Projections of Climate Suitability for Wine Production for the Cotnari Wine Region (Romania)

Present Environment and Sustainable Development ◽

10.2478/pesd-2019-0001 ◽

2019 ◽

Vol 13 (1) ◽

pp. 5-18 ◽

Cited By ~ 1

Author(s):

Irimia Liviu Mihai ◽

Patriche Cristian Valeriu ◽

LeRoux Renan ◽

Quénol Herve ◽

Tissot Cyril ◽

...

Keyword(s):

Growing Season ◽

Climatic Conditions ◽

Climate Projections ◽

Lower Zone ◽

Wine Production ◽

White Wines ◽

Growing Season Length ◽

Average Annual Temperature ◽

Climate Suitability ◽

Wine Region

Abstract Climate projections have revealed the perspective of changing the climate of the world's wine regions in the coming decades by diversifying heliothermal resources. Research in the Cotnari winegrowing region over the past decade has shown that the local climate has been affected by such developments especially after 1980. This research continues the series of studies on the climate of the Cotnari winegrowing region through projections of the climatic conditions for the 2020-2100 time period based on the RCP 4.5 scenario. Average annual temperature, warmest month temperature, precipitation during the growing season, length of the growing season and the Huglin, IAOe and AvGST bioclimatic indices for the 2020-2050, 2051-2080 and 2081-2100 time periods indicate the evolution of Cotnari area climate towards suitability for red wines and loss of suitability for the white wines. Climatic suitability classes for wine production, shift between 2020-2100 to the higher, cooler zone of the winegrowing region, narrowing down their surface and disappearing successively at the maximum altitude of 315 m asl. They are further replaced from the lower zone by classes specific to warmer climates. The suitability for white wines, specific to wine region, disappears at the maximum altitude of 315 m asl around 2060, being replaced by climate suitability for the red wine production. The average temperature of the growing season will exceed 19.5°C after 2080, becoming unsuitable for the production of red quality wines of Cabernet Sauvingnon variety. After 2050, in the lower zone of the winegrowing region the warm IH5 class, suitable for Mediterranean varieties such as Carignan and Grenache will install, as compared to temperate IH3 class which characterizes today the lower zone and allows the production of white wines of the local Feteasca albă, Grasa de Cotnari, Frâncușa and Tămâioasa românească varieties. The results suggest the need to develop strategies for adapting the viticulture of the Cotnari area to climate change.

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