article id 68,
                            category
                        Research article
                    
        
                                    
                                    
                            Abstract |
                        
                                    View details
                             |
                            
Full text in PDF |
                        
Author Info
            
                            This study examined the suitability of airborne laser scanner (ALS) data  collected under leaf-off conditions in a forest inventory, in which  deciduous and coniferous trees need to be separated. All analyses were  carried out with leaf-on and leaf-off ALS data collected from the same  study area. Additionally, aerial photographs were utilized in the  Nearest Neighbor (NN) imputations. An area-based approach was used in  this study. Regression estimates of plot volume were more accurate in  the case of leaf-off than leaf-on data. In addition, regression models  were more accurate in coniferous plots than in deciduous plots. The  results of applying leaf-on models with leaf-off data, and vice versa,  indicate that leaf-on and leaf-off data should not be combined since  this causes serious bias. The total volume and volume by coniferous and  deciduous trees was estimated by the NN imputation. In terms of total  volume, leaf-off data provided more accurate estimates than leaf-on  data. In addition, leaf-off data discriminated between coniferous and  deciduous trees, even without the use of aerial photographs. Accurate  results were also obtained when leaf-off ALS data were used to classify  sample plots into deciduous and coniferous dominated plots. The results  indicate that the area-based method and ALS data collected under  leaf-off conditions are suitable for forest inventory in which deciduous  and coniferous trees need to be distinguished.
                        
                
                                            - 
                            Villikka,
                            University of Easten Finland, Department of Forest Sciences, Joensuu, Finland
                                                        E-mail:
                                                            mv@nn.fi
                                                                                
- 
                            Packalén,
                            University of Easten Finland, Department of Forest Sciences, Joensuu, Finland
                                                        E-mail:
                                                            petteri.packalen@uef.fi
                                                                                          
- 
                            Maltamo,
                            University of Easten Finland, Department of Forest Sciences, Joensuu, Finland
                                                        E-mail:
                                                            mm@nn.fi