This study was conducted to fit the diameter-height data of Quercusglaucain Jeju Island, South Korea to the four commonly used stem taper equations andto evaluate the performance of the four stem taper models using fo...This study was conducted to fit the diameter-height data of Quercusglaucain Jeju Island, South Korea to the four commonly used stem taper equations andto evaluate the performance of the four stem taper models using four statistical criteria: Fit index (FI), root mean square error (RMSE), bias (),and absolute mean difference (AMD). Results showed that the Kozak02stem taper equation provided the best FI(0.9847), RMSE(1.5745),(-0.0030 cm) and AMD (1.0990 cm) whileMax and Burkhart model had the poorest performance among the four stem taper models based on the four evaluation statistics (FI : 0.9793,RMSE : 1.8272, : 0.3040 cm and AMD : 1.3060 cm). These stem taper equations can serve as a useful tool for forest managers in estimating the diameter outside bark at any given height, merchantable stem volumes and total stem volumesof the standing trees of Quercusglaucain theGotjawal forests located in Mount Halla, Jeju Island, South Korea.展开更多
This study was conducted to evaluate the performance of six stem taper models on four tropical tree species, namely Celtis luzonica(Magabuyo),Diplodiscus paniculatus(Balobo), Parashorea malaanonan(Bagtikan), and Swiet...This study was conducted to evaluate the performance of six stem taper models on four tropical tree species, namely Celtis luzonica(Magabuyo),Diplodiscus paniculatus(Balobo), Parashorea malaanonan(Bagtikan), and Swietenia macrophylla(Mahogany) in Mount Makiling Forest Reserve(MMFR), Philippines using fit statistics and lack-of-fit statistics. Four statistical criteria were used in this study, including the standard error of estimate(SEE),coefficient of determination(R^2), mean bias( E),and absolute mean difference(AMD). For the lack-offit statistics, SEE, E and AMD were determined in different relative height classes. The results indicated that the Kozak02 stem taper model offered the best fit for the four tropical species in most statistics. The Kozak02 model also consistently provided the best performance in the lack-of-fit statistics with the best SEE, E and AMD in most of the relative height classes. These stem taper equations could help forest managers and researchers better estimate the diameter of the outside bark with any given height,merchantable stem volumes and total stem volumes of standing trees belonging to the four species of thetropical forest in MMFR.展开更多
基金the support of the Korea Forest Science and Warm Temperate and Subtropical Forest Research Center,Korea Forest Research Institute
文摘This study was conducted to fit the diameter-height data of Quercusglaucain Jeju Island, South Korea to the four commonly used stem taper equations andto evaluate the performance of the four stem taper models using four statistical criteria: Fit index (FI), root mean square error (RMSE), bias (),and absolute mean difference (AMD). Results showed that the Kozak02stem taper equation provided the best FI(0.9847), RMSE(1.5745),(-0.0030 cm) and AMD (1.0990 cm) whileMax and Burkhart model had the poorest performance among the four stem taper models based on the four evaluation statistics (FI : 0.9793,RMSE : 1.8272, : 0.3040 cm and AMD : 1.3060 cm). These stem taper equations can serve as a useful tool for forest managers in estimating the diameter outside bark at any given height, merchantable stem volumes and total stem volumesof the standing trees of Quercusglaucain theGotjawal forests located in Mount Halla, Jeju Island, South Korea.
基金support from Kongju National University Research Grant (2014)
文摘This study was conducted to evaluate the performance of six stem taper models on four tropical tree species, namely Celtis luzonica(Magabuyo),Diplodiscus paniculatus(Balobo), Parashorea malaanonan(Bagtikan), and Swietenia macrophylla(Mahogany) in Mount Makiling Forest Reserve(MMFR), Philippines using fit statistics and lack-of-fit statistics. Four statistical criteria were used in this study, including the standard error of estimate(SEE),coefficient of determination(R^2), mean bias( E),and absolute mean difference(AMD). For the lack-offit statistics, SEE, E and AMD were determined in different relative height classes. The results indicated that the Kozak02 stem taper model offered the best fit for the four tropical species in most statistics. The Kozak02 model also consistently provided the best performance in the lack-of-fit statistics with the best SEE, E and AMD in most of the relative height classes. These stem taper equations could help forest managers and researchers better estimate the diameter of the outside bark with any given height,merchantable stem volumes and total stem volumes of standing trees belonging to the four species of thetropical forest in MMFR.