Relation between photosynthetic capacity and cold hardiness in Scots pine

Abstract. The seasonality of the NEE of the northern boreal coniferous forests was investigated by means of inversion modelling using eddy covariance data. Eddy covariance data was used to optimize the biochemical model parameters. Our study sites consisted of three Scots pine (l. Pinus sylvestris) forests and one Norway spruce (l. Picea abies) forest that were located in Finland and Sweden. We obtained temperature and seasonal dependence for the biochemical model parameters: the maximum rate of carboxylation (V c(max) ) and the maximum rate of electron transport (J max ). Both of the parameters were optimized without assumptions about their mutual magnitude. The values obtained for the biochemical model parameters were similar at all the sites during summer time. To describe seasonality, different temperature fits were made for the spring, summer and autumn periods. During summer, average J max across the sites was 54.0 µmol m −2 s −1 (variance 31.2 µmol m −2 s −1 ) and V c(max) was 12.0 µmol m −2 s −1 (variance 6.6 µmol m −2 s −1 ) at 17 • C. The sensitivity of the model to LAI and atmospheric soil water stress was also studied. The impact of seasonality on annual GPP was 17% when only summertime parameterization was used throughout the year compared to seasonally changing parameterizations.

show abstract

“…We were also able to capture the decrease in the photosynthetic capacity during autumn, as has been observed in e.g. Repo et al (2006).…”

Section: Discussionmentioning

confidence: 86%

Assessing seasonality of biochemical CO<sub>2</sub> exchange model parameters from micrometeorological flux observations at boreal coniferous forest

et al. 2008

View full text Add to dashboard Cite

show abstract

“…Despite continuous freezing air temperatures during the winter of 2004-2005, the apparent quantum yield remained close to 0.1 in the present study. Unlike in lingonberry, quantum yield decreases from approximately 0.05 in late summer to nearly zero in winter in the needles of Scots pine (Pinus sylvestris); consequently, no photosynthesis can be detected (Repo et al 2006). The ability of lingonberry to maintain a high quantum yield probably depends on the presence of a protective snow cover.…”

Section: Discussionmentioning

confidence: 98%

“…As nights lengthen and chilling temperatures arrive, plants begin cold hardening and their frost resistance increases (Sakai and Larcher 1987). During the cold hardening, the photosynthetic capacity of evergreen conifers decreases gradually (Repo et al 2006). Both low temperatures and shortening of the photoperiod contribute to this decrease (Ö quist et al 1980;Vogg et al 1998).…”

Section: Introductionmentioning

confidence: 99%

Recovery of photosynthetic capacity in Vaccinium vitis-idaea during mild spells in winter

2011

View full text Add to dashboard Cite

Recent studies suggest that evergreen plants may maintain their photosynthetic capacity through the winter. Since mild winters are predicted to be more frequent in the future, the metabolic activity of plants is also likely to increase. The aim of the present study was to assess how various environmental factors, such as temperature, photoperiod and preceding frost, affect the recovery of photosynthesis during a mild spell in winter. The recovery of photosynthesis was studied in a series of growth chamber experiments where the overwintering of lingonberry (Vaccinium vitis-idaea) was interrupted by an intermittent warm spell of 1 week during different phases of winter. Rapid activation was observed in all the experiments during the first 3-4 days. No obvious effects of the phase of winter or photoperiod on the recovery of photosynthesis were observed, but a severe freezing treatment prior to the warm spell retarded the recovery significantly. Once recovered, however, lingonberry was able to maintain high rates of photosynthesis even at nearfreezing temperatures, which prevail in their natural sub-nivean environment. The apparent quantum yield of photosynthesis remained high through the winter for lingonberry. This may prove advantageous for evergreen dwarf shrubs which overwinter in dim environments under snow.

show abstract

“…Although research related to the influence of cold acclimation on the photoprotective mechanism in woody plants have been made under natural or controlled environmental conditions (Doulis et al 1993, Repo et al 1996, Wang 1996, Li et al 2002, 2004, Verhoeven et al 2005, Repo et al 2006 in Pinus sylvestris, Picea rubens, Pinus ponderosa, and Betula pendula, no information about the protective mechanism in sudden or gradual temperature-decrease conditions have previously been considered.…”

Section: Introductionmentioning

confidence: 98%

Photoprotective mechanisms in cold-acclimated and nonacclimated needles of Picea glehnii

Bae¹,

Choo²,

Ono³

et al. 2010

Photosynt.

View full text Add to dashboard Cite

The response of Picea glehnii, a cold-tolerant species in the boreal zone, to air temperature (T) was investigated for its cold-acclimated needles (i.e. the ones subjected to gradual decrease in T) and nonacclimated needles (i.e. the ones subjected to a sudden decrease in T) were compared under low temperature. Cold-acclimated needles showed a greater increase of zeaxanthin and lutein contents than nonacclimated ones, whereas the nonacclimated needles showed a greater increase of thylakoid-bound ascorbate peroxidase (tAPX) activity than cold-acclimated ones under chilling conditions (after cold acclimation). These results suggest that: (1) low T induces the increase of zeaxanthin and lutein content, and tAPX activity; (2) accumulated zeaxanthin and lutein protect needles from photooxidative stress by dissipating excess energy before the reactive oxygen species (ROS) are formed in response to a gradual decrease in T (with cold acclimation and subsequent chilling condition), and by tAPX scavenging ROS formed in the case of a sudden decrease in T (without cold acclimation and chilling condition).

show abstract

Relation between photosynthetic capacity and cold hardiness in Scots pine

Cited by 29 publications

References 49 publications

Assessing seasonality of biochemical CO<sub>2</sub> exchange model parameters from micrometeorological flux observations at boreal coniferous forest

Assessing seasonality of biochemical CO<sub>2</sub> exchange model parameters from micrometeorological flux observations at boreal coniferous forest

Recovery of photosynthetic capacity in Vaccinium vitis-idaea during mild spells in winter

Photoprotective mechanisms in cold-acclimated and nonacclimated needles of Picea glehnii

Contact Info

Product

Resources

About

Relation between photosynthetic capacity and cold hardiness in Scots pine

Cited by 29 publications

References 49 publications

Assessing seasonality of biochemical CO&lt;sub&gt;2&lt;/sub&gt; exchange model parameters from micrometeorological flux observations at boreal coniferous forest

Assessing seasonality of biochemical CO&lt;sub&gt;2&lt;/sub&gt; exchange model parameters from micrometeorological flux observations at boreal coniferous forest

Recovery of photosynthetic capacity in Vaccinium vitis-idaea during mild spells in winter

Photoprotective mechanisms in cold-acclimated and nonacclimated needles of Picea glehnii

Contact Info

Product

Resources

About

Assessing seasonality of biochemical CO<sub>2</sub> exchange model parameters from micrometeorological flux observations at boreal coniferous forest

Assessing seasonality of biochemical CO<sub>2</sub> exchange model parameters from micrometeorological flux observations at boreal coniferous forest