README
======

Dataset title:
Data for: Fridell et al. - Photoperiod does not affect thermal acclimation of shoot-scale gas exchange but is important for shoot development in cuttings of Norway spruce (Picea abies (L.) H. Karst)

Creators:
Astrid Fridell, Göran Wallin, Curt Almqvist, Lasse Tarvainen

Responsible organization:
University of Gothenburg

See the Researchdata.se catalogue entry for this dataset for complete metadata, including the dataset description, recommended citation, contact information, and information about how to obtain the dataset. 
https://doi.org/10.5878/pjgb-yy92

Description: 
The data set contains measurement data collected during a factorial day length x warming experiment on Norway spruce (Picea abies (L.) H. Karst) cuttings of two geographical origins. The cuttings were exposed to combinations of long (20 hours of daylight) or short (14 hours of daylight) days and warm (25/20 °C day/night) and cool (15/10 °C day/night) growing conditions for three months in growth chambers.

Collected data include gas exchange variables measured using a Li-Cor 6400 portable photosynthesis system for determination of light response curves and photosynthetic responses to differing intercellular CO2 concentrations (A-Ci curves). Needle properties including leaf mass per area and nitrogen content were determined. In addition, the height growth of the cuttings and the rate of bud development was observed under the different treatment conditions.


License: none applied


Essential information for dataset reuse.
----------------------------------------

The sample cell CO2 concentrations reported in the data file used for determining A-Ci curves have been corrected for diffusion leaks according to the Li-6400 manual (2011 version).

Dataset organization
--------------------

The data set is divided into fives files:
1) Fridell et al - spruce - Variable definitions
2) Fridell et al - spruce - AQ Licor data
3) Fridell et al - spruce - ACI Licor data
4) Fridell et al - spruce - Needle property data
5) Fridell et al - spruce - Height growth and bud development data


Datafile descriptions
----------------------

1) "Fridell et al - spruce - Variable definitions" - Contains definitions of the variables names and units used in the data files 
2) "Fridell et al - spruce - AQ Licor data" - Contains the gas exchange data for generating light response curves
3) "Fridell et al - spruce - ACI Licor data" - Contains the gas exchange data for generating A-Ci curves 
4) "Fridell et al - spruce - Needle property data" - Contains needle property data, also includes data on tree origin 
5) "Fridell et al - spruce - Height growth and bud development data" - Contains height growth and bud development data
 

Reference information
---------------------

Abbreviations:
Please refer to the file "Fridell et al - spruce - Variable definitions" for definitions of abbreviations used in the data files

Data Quality:
Normal operating procedures and quality control measures were followed during the measurements - for further details please see the publication in which the data were used. The sample cell CO2 concentrations reported in the data file used for determining A-Ci curves have been corrected for diffusion leaks according to the Li-6400 manual (2011 version). All other included data are raw data from the measurements - we suggest that any user of this data conducts their own quality control of the light and CO2 response curves using their preferred method.

Publication: The dataset is used and the methodology described in more detail in Fridell et al. 2025 Photoperiod does not affect thermal acclimation of shoot-scale gas exchange but is important for shoot development in cuttings of Norway spruce (Picea abies (L.) H. Karst), Tree Physiology, 2025;, tpaf112, https://doi.org/10.1093/treephys/tpaf112"
