Analysis of tree volume equations for Cherul Forest Reserve, Terengganu

• 主要作者: Mohd Mushar, Siti Hajar
• 格式: Thesis
• 語言: 英语; 英语
• 出版: 2021
• 主題: S Agriculture (General); SD Forestry
• 在線閱讀: http://eprints.utem.edu.my/id/eprint/25986/1/Analysis%20of%20tree%20volume%20equations%20for%20Cherul%20Forest%20Reserve%2C%20Terengganu.pdf; http://eprints.utem.edu.my/id/eprint/25986/2/Analysis%20of%20tree%20volume%20equations%20for%20Cherul%20Forest%20Reserve%2C%20Terengganu.pdf

With the forestry and logging activities contributing to 5.4% of the agricultural sector in the Malaysia’s 2019 GDP growth, this had thus implied the forest as having a significant role in national growth and the critical need of a precise tree volume estimation. Other than that, the forest also plays a pivotal role in forest management and administration as the tree volume assessment is a key element in the establishment of an efficient forest management plan for longrun sustainability. It has been highlighted in the 38th Majlis Urusan Hutan dan Silvikultur (MAJURUS) where each Forest Management Unit (FMU) is preferable to have their own local volume table. Research has therefore been conducted to be align with the issue highlighted by MAJURUS as the current practice by the Forestry Department Peninsular Malaysia (FDPM) is that the same volume table been used throughout all forest reserves in Malaysia and there is also a limited number of study performed on developing a volume table. Therefore, this research is to fill the gap by performing the development and validation of local and standard volume model for Malaysia’s forest reserve. Briefly, a volume table can be developed through several ways and one of it is by deriving from the volume function. In this research, the performance of several log formulas against several log sectional lengths will be tested. Results of the assessment show that Huber of 2 m log sectional length is the best as it recorded the least bias and lowest value of mean square error (MSE). The development of local and standard volume model is then performed by using one of the most powerful tools in analyzing the data of natural and physical sciences, which is regression analysis. The regression analysis consists of two phase which is relationship testing and volume equation modelling. 15 volume models were tested and the performance of each model will be assessed from the result of several statistical tests. The developed local and standard volume model is then validated against the current volume table practiced by the FDPM and developed volume table by the previous scholar for one of the secondary growth forest in Malaysia. The finding from the research found that the current volume table practiced by the FDPM tends to overestimate the estimation for diameter at breast height (DBH) that is greater than 40 cm which represented by 89.16% while the constructed volume models in this study have a higher accuracy level than the previous scholar as it records 0.1565 of root mean square error (RMSE) lower than the previous scholar. Hence, this is clearly shown that the current volume table practiced by the FDPM is less reliable to be used for all forest reserves in Malaysia and there is a significant difference between the volume model developed for a different forest reserve. This is therefore in alignment with the issue highlighted by the MAJURUS.