Global-scale pattern of peatland &lt;i&gt;Sphagnum&lt;/i&gt; growth driven by photosynthetically active  radiation and growing season length

Abstract. High-latitude peatlands contain about one third of the world's soil organic carbon, most of which is derived from partly decomposed Sphagnum (peat moss) plants. We conducted a meta-analysis based on a global dataset of Sphagnum growth measurements collected from published literature to investigate the effects of bioclimatic variables on Sphagnum growth. Analysis of variance and general linear models were used to relate Sphagnum magellanicum and S. fuscum growth rates to photosynthetically active radiation integrated over the growing season (PAR0) and a moisture index. We found that PAR0 was the main predictor of Sphagnum growth for the global dataset, and effective moisture was only correlated with moss growth at continental sites. The strong correlation between Sphagnum growth and PAR0 suggests the existence of a global pattern of growth, with slow rates under cool climate and short growing seasons, highlighting the important role of temperature and growing season length in explaining peatland biomass production. Large-scale patterns of cloudiness during the growing season might also limit moss growth. Although considerable uncertainty remains over the carbon balance of peatlands under a changing climate, our results suggest that increasing PAR0 as a result of global warming and lengthening growing seasons could promote Sphagnum growth. Assuming that production and decomposition have the same sensitivity to temperature, this enhanced growth could lead to greater peat-carbon sequestration, inducing a negative feedback to climate change.

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Global-scale pattern of peatland <i>Sphagnum</i> growth driven by photosynthetically active radiation and growing season length

Biogeosciences ◽

10.5194/bg-9-2737-2012 ◽

2012 ◽

Vol 9 (7) ◽

pp. 2737-2746 ◽

Cited By ~ 59

Author(s):

J. Loisel ◽

A. V. Gallego-Sala ◽

Z. Yu

Keyword(s):

Photosynthetically Active Radiation ◽

Growing Season ◽

Peat Moss ◽

Season Length ◽

Data Set ◽

Active Radiation ◽

Growing Season Length ◽

Growing Seasons ◽

Bioclimatic Variables ◽

Global Data

Abstract. High-latitude peatlands contain about one third of the world's soil organic carbon, most of which is derived from partly decomposed Sphagnum (peat moss) plants. We conducted a meta-analysis based on a global data set of Sphagnum growth measurements collected from published literature to investigate the effects of bioclimatic variables on Sphagnum growth. Analysis of variance and general linear models were used to relate Sphagnum magellanicum and S. fuscum growth rates to photosynthetically active radiation integrated over the growing season (PAR0) and a moisture index. We found that PAR0 was the main predictor of Sphagnum growth for the global data set, and effective moisture was only correlated with moss growth at continental sites. The strong correlation between Sphagnum growth and PAR0 suggests the existence of a global pattern of growth, with slow rates under cool climate and short growing seasons, highlighting the important role of growing season length in explaining peatland biomass production. Large-scale patterns of cloudiness during the growing season might also limit moss growth. Although considerable uncertainty remains over the carbon balance of peatlands under a changing climate, our results suggest that increasing PAR0 as a result of global warming and lengthening growing seasons, without major change in cloudiness, could promote Sphagnum growth. Assuming that production and decomposition have the same sensitivity to temperature, this enhanced growth could lead to greater peat-carbon sequestration, inducing a negative feedback to climate change.

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Human Contribution to the Lengthening of the Growing Season during 1950–99

Journal of Climate ◽

10.1175/2007jcli1568.1 ◽

2007 ◽

Vol 20 (21) ◽

pp. 5441-5454 ◽

Cited By ~ 55

Author(s):

Nikolaos Christidis ◽

Peter A. Stott ◽

Simon Brown ◽

David J. Karoly ◽

John Caesar

Keyword(s):

Growing Season ◽

Future Climate Change ◽

Season Length ◽

Growing Season Length ◽

Growing Seasons ◽

Detection Analysis ◽

Observation Area ◽

Anthropogenic Component ◽

Rate Of Increase ◽

Socioeconomic Consequences

Abstract Increasing surface temperatures are expected to result in longer growing seasons. An optimal detection analysis is carried out to assess the significance of increases in the growing season length during 1950–99, and to measure the anthropogenic component of the change. The signal is found to be detectable, both on global and continental scales, and human influence needs to be accounted for if it is to be fully explained. The change in the growing season length is found to be asymmetric and largely due to the earlier onset of spring, rather than the later ending of autumn. The growing season length, based on exceedence of local temperature thresholds, has a rate of increase of about 1.5 days decade−1 over the observation area. Local variations also allow for negative trends in parts of North America. The analysis suggests that the signal can be attributed to the anthropogenic forcings that have acted on the climate system and no other forcings are necessary to describe the change. Model projections predict that under future climate change the later ending of autumn will also contribute significantly to the lengthening of the growing season, which will increase in the twenty-first century by more than a month. Such major changes in seasonality will affect physical and biological systems in several ways, leading to important environmental and socioeconomic consequences and adaptation challenges.

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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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