The effect of fertilization on early growth of konara oak and Japanese zelkova seedlings planted in a harvested pitch pine plantation

We determined a suitable amount of fertilizer for konara oak（Quercus serrata） and Japanese zelkova（Zelkova serrata） planted in a harvested pitch pine（Pinus rigida） plantation. Two-year-old bare-root seedlings of konara oak and one-year-old containerized seedlings of Japanese zelkova were planted in April 2011. Three plots were established for each tree species to evaluate each of three fertilization applications. Solid compound fertilizer（N：P：K = 3：4：1） was applied yearly in three amounts（control： no fertilization, F1： 180 kg ha-1, and F2：360 kg ha-1）, every May from 2011 to 2013. We measured the root collar diameter and height, and analyzed the compartmental N and P concentrations. Compartmental N concentrations of konara oak and Japanese zelkova were not consistent based on amount of fertilization. However,the compartmental P concentrations of konara oak and Japanese zelkova were significantly different in the order of F2, F1, and control. Although the differences in growth of konara oak appeared after 3 years of fertilization,Japanese zelkova showed differences after only 2 years of fertilization owing to differences in seedling type. Growth of konara oak was affected by fertilization at F1 and F2 in2013. However, growth of Japanese zelkova was affected only at F2. Nutrient demand of Japanese zelkova appeard to be higher than that of konara oak, at least during the early growing period. Results from this study could be practically used in harvested pitch pine plantations to determine appropriate fertilization regimes.

Estimation of carbon storage based on individual tree detection in Pinus densiflora stands using a fusion of aerial photography and LiDAR data

The objective of this study was to estimate the carbon storage capacity of Pinus densiflora stands using remotely sensed data by combining digital aerial photography with light detection and ranging(LiDAR) data.A digital canopy model(DCM),generated from the LiDAR data,was combined with aerial photography for segmenting crowns of individual trees.To eliminate errors in over and under-segmentation,the combined image was smoothed using a Gaussian filtering method.The processed image was then segmented into individual trees using a marker-controlled watershed segmentation method.After measuring the crown area from the segmented individual trees,the individual tree diameter at breast height(DBH) was estimated using a regression function developed from the relationship observed between the field-measured DBH and crown area.The above ground biomass of individual trees could be calculated by an image-derived DBH using a regression function developed by the Korea Forest Research Institute.The carbon storage,based on individual trees,was estimated by simple multiplication using the carbon conversion index(0.5),as suggested in guidelines from the Intergovernmental Panel on Climate Change.The mean carbon storage per individual tree was estimated and then compared with the field-measured value.This study suggested that the biomass and carbon storage in a large forest area can be effectively estimated using aerial photographs and LiDAR data.

利用航空影像和雷达数据估算韩国单株个体赤松林的碳储量

利用航空影像和激光雷达数据,对韩国赤松林的碳储量进行了估算.基于雷达数据建立数字冠层模型,再与航空影像融合,进而划分单株树木的冠幅范围.为消除分段误差,采用高斯滤波方法对融合后的影像进行平滑,然后利用标记控制阈值分割方法提取出单株树木的冠幅范围,再通过建立实测冠幅面积和胸径间的回归方程计算出单株树木的胸径.在此基础上,利用韩国森林研究所建立的回归模型,计算单株树木的地上生物量.单株树木的碳储量由地上生物量乘以转化系数(0.5)得到.结果显示,用此方法估算的平均单株树木碳储量为193.7kgC,与实际测量值223.8kgC较为接近,说明本研究提供的基于航空影像和雷达的方法,可以有效地估算大面积森林树木的生物量和碳储量.