Verification and Validation of Sampling Intensities in the Pre-Felling Inventory of a Tropical Forest in Peninsular Malaysia

This study was carried out on a randomly chosen 40 ha (800 m x 500 m) forest area within the 50 ha Demography Project of the Forest Research Institute Malaysia (FRIM) in Pasoh Forest Reserve, Negri Sembilan. A total of 30h a out of 40 ha study area were used as a Calibration data set and the 10 h...

Full description

Saved in:

Bibliographic Details
Main Author:	Wan Ahmad, Wan Mohd Shukri
Format:	Thesis
Language:	English English
Published:	1997
Subjects:	Forests and forestry - Pasoh Forest Reserve - Negeri Sembilan.
Online Access:	http://psasir.upm.edu.my/id/eprint/9949/1/FH_1997_6_A.pdf
Tags:	Add Tag No Tags, Be the first to tag this record!

id	my-upm-ir.9949
record_format	uketd_dc
spelling	my-upm-ir.99492012-07-18T02:41:29Z Verification and Validation of Sampling Intensities in the Pre-Felling Inventory of a Tropical Forest in Peninsular Malaysia 1997 Wan Ahmad, Wan Mohd Shukri This study was carried out on a randomly chosen 40 ha (800 m x 500 m) forest area within the 50 ha Demography Project of the Forest Research Institute Malaysia (FRIM) in Pasoh Forest Reserve, Negri Sembilan. A total of 30h a out of 40 ha study area were used as a Calibration data set and the 10 ha remaining area as a Validation data set. The percent sample or intensity of sampling was determined at various confidence and error levels, viz., from 80% to 95% confidence with ± 5% to ± 20% error in estimating tree density, basal area and volume. Results obtained from both calibration and validation data sets were used to assess the notion that the statistical reliability of the SMS's Pre-felling inventory (by Forestry Department Peninsular Malaysia) is at 95% confidence and ± 20% error levels. Results showed different intensities of sampling regarding classification into diameter, plot size and species groups to the three parameters measured at different confidence and error levels. At 1% sampling intensity to inventorise density of trees 5 cm - <15 cm dbh in 10 m x 10 m plot, the confidence and error levels of respectively 95% and ± 15% or 90% and ± 10% would be better reliability levels. The 95% and ± 15% levels were also true for estimating basal area and volume. At 5% sampling intensity of trees 15 cm - <30 cm dbh (20 m x 25 m plot), its reliability was at 90% confidence and ± 10% error limits for either tree density, basal area or volume estimation. However, at 10% sampling intensity of trees ≥30 cm dbh (20 m x 50 m plot), the 95% confidence and ± 20% error held true in estimating tree volume. Classification into species groups showed that higher sampling intensity was needed to sample volume of Dipterocarps species compared to tree density, basal area and other species groups at any confidence and error levels. Results also showed that plot 10m x 10m yielded lower sampling intensity for trees <30cm dbh and plot 20 m x 25 m for trees ≥30 cm dbh at any confidence and error levels. The implications of attaching confidence and error levels to the sampling intensity are also discussed. Forests and forestry - Pasoh Forest Reserve - Negeri Sembilan. 1997 Thesis http://psasir.upm.edu.my/id/eprint/9949/ http://psasir.upm.edu.my/id/eprint/9949/1/FH_1997_6_A.pdf application/pdf en public masters Universiti Putra Malaysia Forests and forestry - Pasoh Forest Reserve - Negeri Sembilan. Faculty of Forestry English
institution	Universiti Putra Malaysia
collection	PSAS Institutional Repository
language	English English
topic	Forests and forestry - Pasoh Forest Reserve - Negeri Sembilan.
spellingShingle	Forests and forestry - Pasoh Forest Reserve - Negeri Sembilan. Wan Ahmad, Wan Mohd Shukri Verification and Validation of Sampling Intensities in the Pre-Felling Inventory of a Tropical Forest in Peninsular Malaysia
description	This study was carried out on a randomly chosen 40 ha (800 m x 500 m) forest area within the 50 ha Demography Project of the Forest Research Institute Malaysia (FRIM) in Pasoh Forest Reserve, Negri Sembilan. A total of 30h a out of 40 ha study area were used as a Calibration data set and the 10 ha remaining area as a Validation data set. The percent sample or intensity of sampling was determined at various confidence and error levels, viz., from 80% to 95% confidence with ± 5% to ± 20% error in estimating tree density, basal area and volume. Results obtained from both calibration and validation data sets were used to assess the notion that the statistical reliability of the SMS's Pre-felling inventory (by Forestry Department Peninsular Malaysia) is at 95% confidence and ± 20% error levels. Results showed different intensities of sampling regarding classification into diameter, plot size and species groups to the three parameters measured at different confidence and error levels. At 1% sampling intensity to inventorise density of trees 5 cm - <15 cm dbh in 10 m x 10 m plot, the confidence and error levels of respectively 95% and ± 15% or 90% and ± 10% would be better reliability levels. The 95% and ± 15% levels were also true for estimating basal area and volume. At 5% sampling intensity of trees 15 cm - <30 cm dbh (20 m x 25 m plot), its reliability was at 90% confidence and ± 10% error limits for either tree density, basal area or volume estimation. However, at 10% sampling intensity of trees ≥30 cm dbh (20 m x 50 m plot), the 95% confidence and ± 20% error held true in estimating tree volume. Classification into species groups showed that higher sampling intensity was needed to sample volume of Dipterocarps species compared to tree density, basal area and other species groups at any confidence and error levels. Results also showed that plot 10m x 10m yielded lower sampling intensity for trees <30cm dbh and plot 20 m x 25 m for trees ≥30 cm dbh at any confidence and error levels. The implications of attaching confidence and error levels to the sampling intensity are also discussed.
format	Thesis
qualification_level	Master's degree
author	Wan Ahmad, Wan Mohd Shukri
author_facet	Wan Ahmad, Wan Mohd Shukri
author_sort	Wan Ahmad, Wan Mohd Shukri
title	Verification and Validation of Sampling Intensities in the Pre-Felling Inventory of a Tropical Forest in Peninsular Malaysia
title_short	Verification and Validation of Sampling Intensities in the Pre-Felling Inventory of a Tropical Forest in Peninsular Malaysia
title_full	Verification and Validation of Sampling Intensities in the Pre-Felling Inventory of a Tropical Forest in Peninsular Malaysia
title_fullStr	Verification and Validation of Sampling Intensities in the Pre-Felling Inventory of a Tropical Forest in Peninsular Malaysia
title_full_unstemmed	Verification and Validation of Sampling Intensities in the Pre-Felling Inventory of a Tropical Forest in Peninsular Malaysia
title_sort	verification and validation of sampling intensities in the pre-felling inventory of a tropical forest in peninsular malaysia
granting_institution	Universiti Putra Malaysia
granting_department	Faculty of Forestry
publishDate	1997
url	http://psasir.upm.edu.my/id/eprint/9949/1/FH_1997_6_A.pdf
_version_	1747811032618762240

Verification and Validation of Sampling Intensities in the Pre-Felling Inventory of a Tropical Forest in Peninsular Malaysia

Similar Items