Category :
                    
                    Research article
                                    
                            
                    
        
            
            article id 239,
                            category
                        Research article
                    
        
        
                            Matti Stendahl,
                            Anders Roos.
                    
                    
                (2008).
            
                            
                                    Antecedents and barriers to product innovation – a comparison between innovating and non-innovating strategic business units in the wood industry.
                            
                            
                Silva Fennica
                                                            vol.
                                        42
                                                                            no.
                                        4
                                article id 239.
            
                            
                https://doi.org/10.14214/sf.239
            
             
        
                                    
                                    
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                            Increased competitive pressure from low-cost economies and substituting  materials has raised the need for new strategies focusing on product  differentiation in the Nordic wood industry. With the aim to identify  factors that can facilitate increased product innovation activity, this  study compared organizational characteristics and perceived barriers to  product development among innovating and non-innovating strategic  business units (SBUs) in the Swedish and Finnish wood industry.  Multivariate analysis of data from a cross-sectional sample of 110 SBUs  suggested that organizational size and educational level among  white-collar workers are significant antecedents of product innovation  activity. Furthermore, the difficulty of giving practical priority to  development work in the everyday stress was identified as the most  important perceived barrier to product development among managers in  both innovating and non-innovating SBUs. A low competence level among  the personnel and a low need to innovate was perceived to be the second  most important barriers to product development among managers in,  respectively, innovating and non-innovating SBUs. Practitioners who wish  to increase product innovation activity in the wood industry are  advised to promote an increased educational level in wood industry  companies. They are further encouraged to seek ways to reduce the  perceived barriers to product innovation identified in this study.
                        
                
                                            - 
                            Stendahl,
                            Swedish University of Agricultural Sciences, Department of Forest Products, P.O. Box 7008, SE-750 07 Uppsala, Sweden
                                                        E-mail:
                                                            matti.stendahl@sprod.slu.se
                                                                                        
                                                     
                                            - 
                            Roos,
                            Swedish University of Agricultural Sciences, Department of Forest Products, P.O. Box 7008, SE-750 07 Uppsala, Sweden
                                                        E-mail:
                                                            ar@nn.se
                                                                                
 
                                    
             
         
     
 
            
        
            
            article id 238,
                            category
                        Research article
                    
        
        
                            Mikko Kurttila,
                            Pekka Leskinen,
                            Jouni Pykäläinen,
                            Tiina Ruuskanen.
                    
                    
                (2008).
            
                            
                                    Forest owners' decision support in voluntary biodiversity-protection projects.
                            
                            
                Silva Fennica
                                                            vol.
                                        42
                                                                            no.
                                        4
                                article id 238.
            
                            
                https://doi.org/10.14214/sf.238
            
             
        
                                    
                                    
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                            New forest-biodiversity-protection instruments based on temporary  protection periods and non-industrial private forest owners’ voluntary  participation have been recently introduced and tested in pilot areas  located in Southern Finland. Thanks to their several benefits, the use  of voluntary instruments is becoming more common in many other countries  as well. Voluntary protection here means that forest owners voluntarily  set aside tracts of forest to be protected and define their  compensation fees. Depending on the objectives of the forest owners, the  compensation fee reflects the forest owners’ (positive) attitude  towards biodiversity, scenic beauty, recreational values and/or the  existence of long-term cutting possibilities. When a forest owner  decides to offer part of his/her forest holding to be temporarily  protected, the owner faces a new decision problem related to definition  of the compensation fee, which should be based on diverse information  concerning stand- and holding-level opportunity costs as well as on the  biodiversity value of the stand. This article introduces three  decision-support elements for assisting forest owners in defining their  compensation fees. The first element relates to the assessment of the  potential stand-level loss of timber harvesting income that the  temporary protection of the stand may cause. The second element sets the  holding-level opportunity cost of protection by utilizing the forest  owners’ holding level goals, the holdings’ production possibilities and  optimization methods. The third element describes the biodiversity value  of the stand by means of a multi-criteria expert model. Case study  material collected from the area of Central Karelia Herb-rich Forests  Network pilot project is used to illustrate the characteristics of the  decision-support elements and to point out some development needs for  the future use of these elements.
                        
                
                                            - 
                            Kurttila,
                            University of Joensuu, Faculty of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland
                                                        E-mail:
                                                            mikko.kurttila@joensuu.fi
                                                                                        
                                                     
                                            - 
                            Leskinen,
                            Finnish Environment Institute, Research Programme for Production and Consumption, P.O. Box 111, FI-80101 Joensuu, Finland
                                                        E-mail:
                                                            pl@nn.fi
                                                                                
 
                                            - 
                            Pykäläinen,
                            Metsämonex Ltd., Joensuu, Finland
                                                        E-mail:
                                                            jp@nn.fi
                                                                                
 
                                            - 
                            Ruuskanen,
                            University of Joensuu, Faculty of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland
                                                        E-mail:
                                                            tr@nn.fi
                                                                                
 
                                    
             
         
     
 
            
        
            
            article id 237,
                            category
                        Research article
                    
        
        
                            Jussi Peuhkurinen,
                            Matti Maltamo,
                            Jukka Malinen.
                    
                    
                (2008).
            
                            
                                    Estimating species-specific diameter distributions and saw log recoveries of boreal forests from airborne laser scanning data and aerial photographs: a distribution-based approach.
                            
                            
                Silva Fennica
                                                            vol.
                                        42
                                                                            no.
                                        4
                                article id 237.
            
                            
                https://doi.org/10.14214/sf.237
            
             
        
                                    
                                    
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                            The low-density airborne laser scanning (ALS) data based estimation  methods have been shown to produce accurate estimates of mean forest  characteristics and diameter distributions, according to several  studies. The used estimation methods have been based on the laser canopy  height distribution approach, where various laser pulse height  distribution -derived predictors are related to the stand  characteristics of interest. This approach requires very delicate  selection methods for selecting the suitable predictor variables. In  this study, we introduce a new nearest neighbor search method that  requires no complicated selection algorithm for choosing the predictor  variables and can be utilized in multipurpose situations. The proposed  search method is based on Minkowski distances between the distributions  extracted from low density ALS data and aerial photographs. Apart from  the introduction of a new search method, the aims of this study were: 1)  to produce accurate species-specific diameter distributions and 2) to  estimate factual saw log recovery, using the estimated height-diameter  distributions and a stem data bank. The results indicate that the  proposed method is suitable for producing species-specific diameter  distributions and volumes at the stand level. However, it is proposed,  that the utilization of more extensive and locally emphasized reference  data and auxiliary variables could yield more accurate saw log  recoveries.
                        
                
                                            - 
                            Peuhkurinen,
                            University of Joensuu, Faculty of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland
                                                        E-mail:
                                                            jp@nn.fi
                                                                                        
                                                     
                                            - 
                            Maltamo,
                            University of Joensuu, Faculty of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland
                                                        E-mail:
                                                            mm@nn.fi
                                                                                
 
                                            - 
                            Malinen,
                            Finnish Forest Research Institute, Joensuu Research Unit, P.O. Box 68, FI-80101 Joensuu, Finland
                                                        E-mail:
                                                            jm@nn.fi
                                                                                
 
                                    
             
         
     
 
            
        
            
            article id 236,
                            category
                        Research article
                    
        
        
                            Jaakko Repola.
                    
                    
                (2008).
            
                            
                                    Biomass equations for birch in Finland.
                            
                            
                Silva Fennica
                                                            vol.
                                        42
                                                                            no.
                                        4
                                article id 236.
            
                            
                https://doi.org/10.14214/sf.236
            
             
        
                                    
                                    
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                            Biomass equations were compiled for the above- and below-ground tree components of birch (Betula pendula Roth and Betula pubescens Ehrh.). The equations were based on 127 sample trees in 24 birch stands located on mineral soil sites. The study material consisted of 20 temporary plots and ten plots from four thinning experiments with different thinning intensities (unthinned, moderately and heavily thinned plots). The equations were estimated for the following individual tree components: stem wood, stem bark, living and dead branches, foliage, stump, and roots. In the data analysis, a multivariate procedure was applied in order to take into account the statistical dependency among the equations. Three multivariate variance component models were constructed for the above-ground biomass components, and one for the below-ground biomass components. The multivariate model (1) was mainly based on tree diameter and height, and in the multivariate models (2) and (3) additional commonly measured tree variables were used. The equations provided logical biomass predictions for a number of tree components, and were comparable with other functions used in Finland and Sweden. The applied statistical method generated equations that gave more reliable biomass estimates than the equations presented earlier. Furthermore, the structure of the multivariate models enables more flexible application of the equations, especially for research purposes.
                        
                
                                            - 
                            Repola,
                            Finnish Forest Research Institute, Rovaniemi Research Unit, P.O. Box 16, FI-96301 Rovaniemi, Finland
                                                        E-mail:
                                                            jaakko.repola@metla.fi
                                                                                        
                                                     
                                    
             
         
     
 
            
        
            
            article id 235,
                            category
                        Research article
                    
        
        
                            Ari Nikula,
                            Ville Hallikainen,
                            Risto Jalkanen,
                            Mikko Hyppönen,
                            Kari Mäkitalo.
                    
                    
                (2008).
            
                            
                                    Modelling the factors predisposing Scots pine to moose damage in artificially regenerated sapling stands in Finnish Lapland.
                            
                            
                Silva Fennica
                                                            vol.
                                        42
                                                                            no.
                                        4
                                article id 235.
            
                            
                https://doi.org/10.14214/sf.235
            
             
        
                                    
                                    
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                            Moose (Alces alces) damage in forest plantations have been at a high  level in Finland in recent decades. Nowadays, moose is the most severe  pest in Scots pine plantations also in Finnish Lapland. So far, despite  the high level of damage and different bio-geographical conditions in  Northern Finland, most of the moose-damage research has been carried out  in Southern Finland. A number of research have also been performed to  analyse factors affecting browsing but predictive models are rare. Data  from 123 randomly selected and artificially regenerated pine plantations  in Northern Finland were used in modelling the risk of moose browsing.  The stands had been regenerated during 1984–1995. A total of 508 sample  plots (range 2–8 plots per stand) were measured. Hierarchical logistic  regression models with a random factor were constructed to predict the  probability of leader-shoot browsing of pine on a plot. The number of  planted pines and deciduous trees overtopping the pines were the most  important predictors increasing the browsing probability. The results  support earlier findings that deciduous trees overtopping or reaching  the height of the pines should be cleaned from the immediate vicinity of  the pines. Seedlings with a height ranging from 75 to 299 centimetres  were more susceptible to browsing. Heavy soil scarification, such as  ploughing or mounding, increased the browsing probability compared with  lighter scarification methods. Soil type did not affect the browsing  probability, but paludification decreased it. The within-stand variation  in deciduous trees density and height should be taken into account in  future moose browsing risk assessments. In Lapland, high moose damage  risk areas are characterized by a low elevation and higher temperature  sum.
                        
                
                                            - 
                            Nikula,
                            Finnish Forest Research Institute, Rovaniemi Research Unit, Eteläranta 55, FI-96300 Rovaniemi, Finland
                                                        E-mail:
                                                            ari.nikula@metla.fi
                                                                                        
                                                     
                                            - 
                            Hallikainen,
                            Finnish Forest Research Institute, Rovaniemi Research Unit, Eteläranta 55, FI-96300 Rovaniemi, Finland
                                                        E-mail:
                                                            vh@nn.fi
                                                                                
 
                                            - 
                            Jalkanen,
                            Finnish Forest Research Institute, Rovaniemi Research Unit, Eteläranta 55, FI-96300 Rovaniemi, Finland
                                                        E-mail:
                                                            rj@nn.fi
                                                                                
 
                                            - 
                            Hyppönen,
                            Finnish Forest Research Institute, Rovaniemi Research Unit, Eteläranta 55, FI-96300 Rovaniemi, Finland
                                                        E-mail:
                                                            mh@nn.fi
                                                                                
 
                                            - 
                            Mäkitalo,
                            Finnish Forest Research Institute, Rovaniemi Research Unit, Eteläranta 55, FI-96300 Rovaniemi, Finland
                                                        E-mail:
                                                            km@nn.fi
                                                                                
 
                                    
             
         
     
 
            
        
            
            article id 234,
                            category
                        Research article
                    
        
        
                            Enni Flykt,
                            Sari Timonen,
                            Taina Pennanen.
                    
                    
                (2008).
            
                            
                                    Variation of ectomycorrhizal colonisation in Norway spruce seedlings in Finnish forest nurseries.
                            
                            
                Silva Fennica
                                                            vol.
                                        42
                                                                            no.
                                        4
                                article id 234.
            
                            
                https://doi.org/10.14214/sf.234
            
             
        
                                    
                                    
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                            Ectomycorrhizal (ECM) colonisation patterns and seedling growth of  containerised spruce seedlings were studied in five typical Finnish  forest nurseries by morphotyping and molecular characterisation. ECM  colonisation degree of 1-year-old spruce seedlings was below 20% in all  studied Finnish forest nurseries. In 2-year-old spruce seedlings the ECM  colonisation degree was ca. 50–60% in three of the nurseries, but  negligible in others. The ECM fungal species richness varied from 0.1 to  3.8 types per seedling. Altogether seven ECM morphotypes were  distinguished. The clearest factors associated with ECM colonisation  patterns were nitrogen and phosphorus fertilisation. Particularly  fertilisation in the early stage of seedling development appeared to  diminish the degree of colonisation and species richness of ECM fungi.  Root/shoot ratio was positively correlated with high colonisation degree  and species richness of ECM fungi. Higher fertilisation inputs in these  overall fertilisation levels did not increase the size of the  seedlings. According to these results moderate fertilisation levels  particularly in the beginning of seedling cultivation are critical for  generating higher root/shoot ratios and sufficient ECM colonisation  degree of the roots.
                        
                
                                            - 
                            Flykt,
                            University of Helsinki, Department of Applied Chemistry and Microbiology, P.O. Box 27, FI-00014 University of Helsinki, Finland
                                                        E-mail:
                                                            ef@nn.fi
                                                                                        
                                                     
                                            - 
                            Timonen,
                            University of Helsinki, Department of Applied Chemistry and Microbiology, P.O. Box 27, FI-00014 University of Helsinki, Finland
                                                        E-mail:
                                                            st@nn.fi
                                                                                
 
                                            - 
                            Pennanen,
                            Finnish Forest Research Institute, Vantaa Research Unit, P.O. Box 18, FI-01301 Vantaa, Finland
                                                        E-mail:
                                                            tp@nn.fi
                                                                                
 
                                    
             
         
     
 
            
        
            
            article id 233,
                            category
                        Research article
                    
        
        
                            Raija Laiho,
                            Sakari Sarkkola,
                            Seppo Kaunisto,
                            Jukka Laine,
                            Kari Minkkinen.
                    
                    
                (2008).
            
                            
                                    Macroscale variation in peat element concentrations in drained boreal peatland forests.
                            
                            
                Silva Fennica
                                                            vol.
                                        42
                                                                            no.
                                        4
                                article id 233.
            
                            
                https://doi.org/10.14214/sf.233
            
             
        
                                    
                                    
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                            Information on the variation in soil element concentrations at different  spatial scales is needed for, e.g., designing efficient sampling  strategies, upscaling the processes related to carbon cycling, and  planning land use and management. In spite of intensive land use, such  information concerning peat soils is still scarce. We analyzed the  variation in peat mineral element concentrations in boreal peatland  forests drained 50–60 years earlier. We wanted to quantify the  proportions of variation deriving from differences between regions and  peatland basins and from within-peatland heterogeneity, and to model the  variation using relatively easily measurable site and soil  characteristics. We utilized 878 peat samples representing the 0–20 cm  layer and collected from 289 sites in 79 peatland basins. The sites  represented three different drained peatland forest site types. The two  strongest gradients in the element composition captured by principal  component analysis were correlated with both the North-South gradient  and the site type variation, and the East-West gradient. In general,  most of the variation in the element concentrations was contributed by  differences among peatland basins, and variation within the  floristically determined sites. Most of the element concentrations were  best modeled when either the bulk density or the ash content of the  peat, or both, were used in addition to site type and geographical  location. The explanatory power remained modest for most element  concentrations. As for the P concentrations in soil, however, our models  provide means for estimating a large part of the variation among  drained pine mire sites.
                        
                
                                            - 
                            Laiho,
                            University of Helsinki, Department of Forest Ecology, FI-00014 University of Helsinki, Finland
                                                        E-mail:
                                                            raija.laiho@helsinki.fi
                                                                                        
                                                     
                                            - 
                            Sarkkola,
                            Finnish Forest Research Institute, Vantaa Research Unit, P.O. Box 18, FI-01301 Vantaa, Finland
                                                        E-mail:
                                                            ss@nn.fi
                                                                                
 
                                            - 
                            Kaunisto,
                            Finnish Forest Research Institute, Parkano Research Unit, Kaironiementie 54, FI-39700 Parkano, Finland
                                                        E-mail:
                                                            sk@nn.fi
                                                                                
 
                                            - 
                            Laine,
                            Finnish Forest Research Institute, Parkano Research Unit, Kaironiementie 54, FI-39700 Parkano, Finland
                                                        E-mail:
                                                            jl@nn.fi
                                                                                
 
                                            - 
                            Minkkinen,
                            University of Helsinki, Department of Forest Ecology, FI-00014 University of Helsinki, Finland
                                                        E-mail:
                                                            km@nn.fi
                                                                                
 
                                    
             
         
     
 
            
        
            
            article id 232,
                            category
                        Research article
                    
        
        
                            Thomas Wutzler.
                    
                    
                (2008).
            
                            
                                    Effect of the aggregation of multi-cohort mixed stands on modeling forest ecosystem carbon stocks.
                            
                            
                Silva Fennica
                                                            vol.
                                        42
                                                                            no.
                                        4
                                article id 232.
            
                            
                https://doi.org/10.14214/sf.232
            
             
        
                                    
                                    
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                            Studies of the carbon sink of forest ecosystems often stratify the  studied stands by the dominating species and thereby abstract from  differences in the mixed-species, multi-cohort structure of many  forests. This case study infers whether the aggregation of forestry data  introduces a bias in the estimates of carbon stocks and their changes  at the scale of individual stands and the scale of a forest district.  The empirical TreeGrOSS-C model was applied to 1616 plots of a forest  district in Central Germany to simulate carbon dynamics in biomass,  woody debris, and soil. In a first approach each stand was explicitly  simulated with all cohorts. In three other approaches the forest  inventory data were aggregated in several ways, including a  stratification of the stands to 110 classes according to the dominating  species, age class, and site conditions. A small but significant bias  was confirmed. At stand scale the initial ecosystem carbon stocks by the  aggregated approach differed from that of the detailed approach by  2.3%, but at the district scale only by 0.05%. The differences in age  between interspersed and dominant cohorts as well as differences in  litter production were important for the differences in initial carbon  stocks. The amounts of wood extracted by thinning operations were  important for the differences in the projection of the carbon stocks  over 100 years. Because of the smallness of bias, this case study  collects evidence that the approaches, that represent stands or stratums  by a single cohort, are valid at the scale of a forest district or  larger.
                        
                
                                            - 
                            Wutzler,
                            Max Planck Institute for Biogeochemistry, Hans Knöll Str. 10, DE-07745, Jena, Germany
                                                        E-mail:
                                                            thomas.wutzler@bgc-jena.mpg.de
                                                                                        
                                                     
                                    
             
         
     
 
            
        
            
            article id 231,
                            category
                        Research article
                    
        
        
                            Hilppa Gregow,
                            Ulla Puranen,
                            Ari Venäläinen,
                            Heli Peltola,
                            Seppo Kellomäki,
                            David Schultz.
                    
                    
                (2008).
            
                            
                                    Temporal and spatial occurrence of strong winds and large snow load amounts in Finland during 1961-2000.
                            
                            
                Silva Fennica
                                                            vol.
                                        42
                                                                            no.
                                        4
                                article id 231.
            
                            
                https://doi.org/10.14214/sf.231
            
             
        
                                    
                                    
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                            Information on the temporal and spatial occurrence of strong winds and snow loads on trees is important for the risk management of wind- and snow-induced damage. Meteorological measurements made at 19 locations across Finland during 1961–2000 are used to understand the temporal and spatial occurrence of strong winds and large snow loads. A Kriging interpolation method was used to produce a spatial analysis of wind-speed events above 11 m s–1, 14 m s–1, and greater or equal to 17 m s–1 and snowfall accumulation above 20 kg m–2 and 30 kg m–2. According to the analysis, wind speeds exceeded 14 m s–1 at least 155 times and reached 17 m s–1 only 5 times at inland locations during the 40 years. Large snowfall accumulations were more frequent in the higher-elevation inland areas than along the coast. The snow load on trees exceeded 20 kg m–2 about 65 times a year when averaged over all 40 years, but was as high as 150 times a year during the mild 1990s. The maximum number of heavy snow-load events occurred in 1994 in northern Finland, consistent with a forest inventory by the Finnish Forest Research Institute in 1992–1994. The findings of this study imply that the risk of wind-induced damage is highest in the late autumn when trees do not have the additional support of frozen soil. In contrast, the risk of snow-induced damage is highest at higher-elevations inland, especially in northern Finland.
* Erratum (23 Oct 2012): The authors have requested inclusion of an additional author. Author information should thus be as follows: Hilppa Gregow, Ulla Puranen, Ari Venäläinen, Heli Peltola, Seppo Kellomäki & David Schultz
                        
                
                                            - 
                            Gregow,
                            Finnish Meteorological Institute, P.O. Box 503, FI-00101 Helsinki, Finland
                                                        E-mail:
                                                            hilppa.gregow@fmi.fi
                                                                                        
                                                     
                                            - 
                            Puranen,
                            Finnish Meteorological Institute, P.O. Box 503, FI-00101 Helsinki, Finland
                                                        E-mail:
                                                            up@nn.fi
                                                                                
 
                                            - 
                            Venäläinen,
                            Finnish Meteorological Institute, P.O. Box 503, FI-00101 Helsinki, Finland
                                                        E-mail:
                                                            av@nn.fi
                                                                                
 
                                            - 
                            Peltola,
                            University of Joensuu, Faculty of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland
                                                        E-mail:
                                                            heli.peltola@uef.fi
                                                                                
 
                                            - 
                            Kellomäki,
                            University of Joensuu, Faculty of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland
                                                        E-mail:
                                                            seppo.kellomaki@uef.fi
                                                                                
 
                                            - 
                            Schultz,
                            Finnish Meteorological Institute, P.O. Box 503, FI-00101 Helsinki, Finland
                                                        E-mail:
                                                            ds@nn.fi
                                                                                
 
                                    
             
         
     
 
            
        
            
            article id 230,
                            category
                        Research article
                    
        
        
                            Risto Jalkanen,
                            Sheila Hicks,
                            Tarmo Aalto,
                            Hannu Salminen.
                    
                    
                (2008).
            
                            
                                    Past pollen production reconstructed from needle production in Pinus sylvestris at the northern timberline: a tool for evaluating palaeoclimate reconstructions.
                            
                            
                Silva Fennica
                                                            vol.
                                        42
                                                                            no.
                                        4
                                article id 230.
            
                            
                https://doi.org/10.14214/sf.230
            
             
        
                                    
                                    
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                            Annual needle production (PROD) of Scots pine (Pinus sylvestris L.) and  pine pollen accumulation rates (PAR) are compared along a 5-site  transect from the Arctic Circle to the northern timberline. PROD is  calculated using the Needle Trace Method (NTM). PAR is monitored by two  series of pollen traps, located in the centres of mires and within  forests, respectively. There is a strong year-to-year agreement in PAR  and PROD between the sites for the common 19-year period for which both  proxies are available. Mean July temperature of the previous year (TJUL–1)  correlates statistically significantly with PROD at all five sites and  with PAR in the four northernmost sites. There is also a significant  relationship between TJUN–1 and PROD at all sites, and TJUN and PAR at the two northernmost sites. PROD and PAR correlate most  strongly in the three near tree line sites, where PROD explains up to  51% of the variation in PAR. On the basis of the calibration between  PROD, PAR and TJUL–1, PROD and TJUL–1 are used to  reconstruct past PAR. That such a reconstruction is realistic is  supported by its agreement with the pollen record for 1982–2000 and with  records of male flowering for the period 1956–1973. The use of PROD in  reconstructing past PAR can help in interpreting the fossil pollen  signal in terms of climate rather than vegetation change and in  evaluating the high-resolution dating of peat profiles and calculations  of the rate of peat accumulation.
                        
                
                                            - 
                            Jalkanen,
                            Finnish Forest Research Institute, Rovaniemi Research Unit, P.O. Box 16, FI-96301 Rovaniemi, Finland
                                                        E-mail:
                                                            risto.jalkanen@metla.fi
                                                                                        
                                                     
                                            - 
                            Hicks,
                            Institute of Geosciences, P.O. Box 3000, FI-90014 University of Oulu, Finland
                                                        E-mail:
                                                            sh@nn.fi
                                                                                
 
                                            - 
                            Aalto,
                            Finnish Forest Research Institute, Rovaniemi Research Unit, P.O. Box 16, FI-96301 Rovaniemi, Finland
                                                        E-mail:
                                                            ta@nn.fi
                                                                                
 
                                            - 
                            Salminen,
                            Finnish Forest Research Institute, Rovaniemi Research Unit, P.O. Box 16, FI-96301 Rovaniemi, Finland
                                                        E-mail:
                                                            hs@nn.fi
                                                                                
 
                                    
             
         
     
 
            
        
            
            article id 229,
                            category
                        Research article
                    
        
        
                            Carmen Martín,
                            Teresa Parra,
                            Margarita Clemente-Muñoz,
                            Esteban Hernández-Bermejo.
                    
                    
                (2008).
            
                            
                                    Genetic diversity and structure of the endangered Betula pendula subsp. fontqueri populations in the south of Spain.
                            
                            
                Silva Fennica
                                                            vol.
                                        42
                                                                            no.
                                        4
                                article id 229.
            
                            
                https://doi.org/10.14214/sf.229
            
             
        
                                    
                                    
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                            Betula pendula subsp. fontqueri, present in the south of Spain, has been  considered in danger of extinction and, for this reason, some regional  governments in Spain have included their populations in conservation  programmes. In order to establish the genetic structure of the Betula  pendula subsp. fontqueri populations, a random amplified polymorphic DNA  (RAPD) analysis was carried out. Two B. pubescens populations were  included in the study as taxonomic controls. B. pendula subsp. fontqueri  populations were clearly differentiated through UPGMA, and showed  significant pairwise genetic distance (ΦST) values between  all pairs of populations obtained by AMOVA. Genetic diversity found  between populations was not correlated to geographical distances. The  significant differences among populations must be due to progressive  isolation of Betula populations along their paleogeographical history,  and more recently to the drastic fragmentation and reduction of some of  these populations. The results obtained in this work show clear genetic  differences which could be considered in the management of conservation  strategies for Betula pendula subsp. fontqueri in its Iberian meridional  distribution.
                        
                
                                            - 
                            Martín,
                            Departamento de Biología Vegetal, Escuela Técnica Superior de Ingenieros Agrónomos de Madrid, Universidad Politécnica de Madrid, Ciudad Universitaria s/n, 28040-Madrid, Spain
                                                        E-mail:
                                                            mariacarmen.martin@upm.es
                                                                                        
                                                     
                                            - 
                            Parra,
                            Departamento de Ciencias y Recursos Agrícolas y Forestales, Universidad de Córdoba, Avda. Linneo s/n, 14004-Córdoba, Spain
                                                        E-mail:
                                                            tp@nn.es
                                                                                
 
                                            - 
                            Clemente-Muñoz,
                            Departamento de Ciencias y Recursos Agrícolas y Forestales, Universidad de Córdoba, Avda. Linneo s/n, 14004-Córdoba, Spain
                                                        E-mail:
                                                            mcm@nn.es
                                                                                
 
                                            - 
                            Hernández-Bermejo,
                            Departamento de Ciencias y Recursos Agrícolas y Forestales, Universidad de Córdoba, Avda. Linneo s/n, 14004-Córdoba, Spain
                                                        E-mail:
                                                            ehb@nn.es