README
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Dataset title:
Data for: Forest Development and financial outcomes under shelterwood and clearcut regimes in mixed stands

Citation:  
Nyberg, T., Holmström, E., Lula, M., & Adekunle, H. (2026). Data för: Forest Development and financial outcomes under shelterwood and clearcut regimes in mixed stands (Version 1) [Data set]. Sveriges lantbruksuniversitet. https://doi.org/10.5878/rmrv-xh80

See the Researchdata.se catalogue entry for this dataset - accessible via the DOI link above - for complete metadata, including the dataset description, contact information and information about how to obtain the dataset. 

Responsible organization:
The Swedish University of Agricultural Sciences 

Description:
Collected field measurements in Sweden during year 2022 and 2023 were used to assess stand development (growth and yield). The objective was to assess if the stands had turned into mixed species forests and if there were any differences in growth and yield between treatments.       

License: CC0

Access restrictions: No


Essential information for dataset reuse.
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Two to four circle plots per treatment and site (block) were laid out, with a radius of 5.64 meters. In each circle plot for every tree above 1.3 meters, tree species and dbh (cross calipered) were noted. Furthermore, for every tree species present in the circle plot, height of the two largest trees and the three closest to the plot centre was measured. The field data was then used as the baseline for the simulations in StandWise, Heureka.

The instruments used for collecting field data were a Vertex 5 (for height measurements) and a calliper (for breast height diameters). R, version 2023.9.1.494, was used to analyse the data and StandWise, Heureka (an open source program) was used for the stand simulations. Open access to Heureka can be found here: https://www.heurekaslu.se/wiki/Heureka_Wiki/sv        


Datafile descriptions
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circle_plot_data.tsv - data collected in the field for each tree above 1.3 meters in dbh per circle plot (5.64 m in radius). 
Columns:
  site - one block per site.
  parcel - four parcel numbers i.e. treatments. 1 = clearcut without mechanical site preparation, 2 = clearcut with mechanical site preparation, 3 = shelterwood without mechanical site preparation, 4 = shelterwood with mechanical site preparation
  cyt - circle plot, level on which the tree data was collected on.
  trsl - tree species, 1 = Pinus sylvestris, 2 = Picea abies, 3 = Betula spp. (B. pendula and B. pubescens), 5 =  Alnus glutinosa, 6 = Alnus incana, 9 = Populus tremula, 12 = Quercus robur, 21 = Larix decidua, 23 = Sorbus aucuparia, 24 = Salix caprea
  d.a [dead or alive] - 1 = alive, 2 = dead.
  d1 [mm] - breast height diameter
  d2 [mm] - breast height diameter	   
    

data_height.tsv - data collected in the field for the height.
  site - site number, one block per site.
  parcel - four parcel numbers i.e. treatments. 1 = clearcut without mechanical site preparation, 2 = clearcut with mechanical site preparation, 3 = shelterwood without mechanical site preparation, 4 = shelterwood with mechanical site preparation
  cyt - circle plot, level on which the tree data was collected on.
  trsl - tree species, 1 = Pinus sylvestris, 2 = Picea abies, 3 = Betula spp. (B. pendula and B. pubescens), 5 =  Alnus glutinosa, 6 = Alnus incana, 9 = Populus tremula, 12 = Quercus robur, 21 = Larix decidua, 23 = Sorbus aucuparia, 24 = Salix caprea
  d1 [mm] - breast height diameter
  d2 [mm] - breast height diameter	   
  dcm [cm] - mean breast height diameter based on the cross calipered measurements (d1 and d2). Equation used to calculate dcm: (sqrt(d1*d2)/10) 
  hm [m] - tree height

calculations_based_on_circle_plot_data.tsv - data calculations based on the collected field data (so the data from data files circle_plot_data.tsv and data_height.tsv).
  site - one block per site.
  parcel - four parcel numbers i.e. treatments. 1 = clearcut without mechanical site preparation, 2 = clearcut with mechanical site preparation, 3 = shelterwood without mechanical site preparation, 4 = shelterwood with mechanical site preparation
  cyt - circle plot, level on which the tree data was collected on.
  trsl - tree species, 1 = Pinus sylvestris, 2 = Picea abies, 3 = Betula spp. (B. pendula and B. pubescens), 5 =  Alnus glutinosa, 6 = Alnus incana, 9 = Populus tremula, 12 = Quercus robur, 21 = Larix decidua, 23 = Sorbus aucuparia, 24 = Salix caprea
  d.a [dead or alive] - 1 = alive, 2 = dead.
  d1 [mm] - breast height diameter
  d2 [mm] - breast height diameter	   
  dcm [cm] - mean breast height diameter based on the cross calipered measurements (d1 and d2). Equation used to calculate dcm: (sqrt(d1*d2)/10)
  vol [dm3] - volume calculated based on dcm and esth, for trees with DBH <4 cm, Andersson’s volume functions (1954) were applied, while for trees with DBH >5 cm, Brandel’s volume function (1990) was used. For trees with a DBH ranging from 4.0 to 5.0 cm, a smoothing function was applied to reduce possible divergence between functions found in Holmström et al. (2016) - Holmström E, Hjelm K, Johansson U, Karlsson M, Valkonen S, Nilsson U (2016) Pre-commercial thinning, birch admixture and sprout management in planted Norway spruce stands in South Sweden. Scand J Forest Res 31: 56-65. https://doi.org/10.1080/02827581.2015.1055792
  esth [m] - tree height was estimated using Näslund’s height function (1947), implemented in R, using the package forestmangr. One α and one β coefficient were estimated for each combination of species, site, and sub-treatment based on the data_height.tsv
  ba [m2] - basal area for each tree, calculated (((dcm/100)/2)*((dcm/100)/2)*pi)    
  volm [m3] - volume in m3, calculated vol/1000

CF_LEV_calculations.xlsx - data from the simulations in StandWise, Heureka DSS.
 Overstory sim for shelterwood and clearcut
  CAI [m3sk/ha, year] - current annual increment 
  MAI [m3sk/ha, year] - mean annual increment
 Understory sim calculations 
  NPV [SEK] - net present value
  LEV [SEK] - land expectation value
  0, 2.5 or 4 [% expressed as decimal] - three differnet interest rates used for calculating NPV and LEV 

Reference information
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Source code information:
  R, version 2023.9.1.494
  StandWise, Heureka 

Data Quality:
In some of the parcels (treatments) there are fewer circular plots due to problems establishing the borders of the treatments in the field

