• Journal of Forest and Environmental Science
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• v.28 no.3
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• pp.144-151
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• 2012

Deforestation is a major and very critical problem faced by many tropical countries including Malaysia. Sabah is the second largest state in Malaysia and its deforestation rate has been accelerating. This study was conducted to monitor the deforestation in Sabah in the last two decades with Landsat images of 1990, 2000 and 2008. Supervised classification with maximum likelihood algorithm was conducted using the Landsat data for monitoring deforestation. In total, between 1990 and 2008, Sabah lost half of its intact forest, or more than 1.85 million ha in less than two decades. Overall, the deforestation rate for all forest types combined for the last two decades was 1.6% per year. Deforestation seemed to be accelerating because the deforestation rate between 1990 and 2000 was 0.9% per year and it had increased to 2.7% per year between 2000 and 2008. The deforestation trend seemed to follow a negative exponential from 1990 to 2008. In contrast, the agricultural areas increased rapidly with a total of increment more than 1 million ha. This confirmed that agriculture especially establishment of commercial plantation was the major factor of deforestation in Sabah for the last two decades.

• Korean Journal of Remote Sensing
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• v.27 no.3
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• pp.315-328
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• 2011

Landsat data incorporated with additional bands-normalized difference vegetation index (NDVI) and band ratios were used to assess the extent and rate of deforestation in the Gunung Mutis Nature Reserve (GMNR), a mountainous tropical forest in Eastern of Indonesia. Hybrid classification was chosen as the classification approach. In this approach, the unsupervised classification-iterative self-organizing data analysis (ISODATA) was used to create signature files and training data set. A statistical separability measurement-transformed divergence (TD) was used to identify the combination of bands that showed the highest distinction between the land cover classes in training data set. Supervised classification-maximum likelihood classification (MLC) was performed using selected bands and the training data set. Post-classification smoothing and accuracy assessment were applied to classified image. Post-classification comparison was used to assess the extent of deforestation, of which the rate of deforestation was calculated by the formula suggested by Food Agriculture Organization (FAO). The results of two periods of deforestation assessment showed that the extent of deforestation during 1989-1999 was 720.72 ha, 0.80% of annual rate of deforestation, and its extent of deforestation during 1999-2009 was 1,059.12 ha, 1.31% of annual rate of deforestation. Such results are important for the GMNR authority to establish strategies, plans and actions for combating deforestation.

• Journal of Korean Society of Forest Science
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• v.101 no.3
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• pp.365-373
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• 2012

This study purposed to extract and assess the accuracy of assessment for deforestation area in Wonju city using medium resolution satellite image. The total size of deforestation area during the last nine years (2000-2008) was about 467 ha, and it was occurred annually about 52 ha. The most frequent form of deforestation was settlements (72%). Ninety percent of the size of deforestation was less than 2 ha in size. In addition, 79 percent of deforestation area was found within 500 m from the road network and within 100 m of the Forest/Non-forest boundary. This study compared the deforestation based on the administrative information (GIS deforestationI) with the deforestation (RS deforestation) extracted from the satellite imagery by vegetation indices (NDVI, NBR, NDWI). Extraction accuracy, mean-standard deviation${\times}1.5$ applied 3 by 3 filtering, showed reliable accuracy 35.47% k-value 0.20. However, error could be occurred because of the difference of land-use change and land-cover change. The actual rate of land-cover change deforestation area was 32% on administrative information. The 7.52% of forest management activities area was misjudged as deforestation by RS deforestation. Finally, the comparison of land-cover change deforestation (GIS deforestationII) with the RS deforestation accuracy, as a result NDVI mean-standard deviation${\times}2$ applied 3 by 3 filtering, showed improved accuracy 61.23%, k-value 0.23.

• Journal of the Korean Association of Geographic Information Studies
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• v.11 no.2
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• pp.108-120
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• 2008

This paper discusses the prediction of deforestation areas using probability models from forest census database, Geographic information system (GIS) database and the land cover database. The land cover data was analyzed using remotely-sensed (RS) data of the Landsat TM data from 1989 to 2001. Over the analysis period of 12 years, the deforestation area was about 40ha. Most of the deforestation areas were attributable to road construction and residential development activities. About 80% of the deforestation areas for residential development were found within 100m of the road network. More than 20% of the deforestation areas for forest road construction were within 100m of the road network. Geographic factors and vegetation change detection (VCD) factors were used in probability models to construct deforestation occurrence map. We examined the size effect of area partition as training area and validation area for the probability models. The Bayes model provided a better deforestation prediction rate than that of the regression model.

• Journal of Korean Society of Forest Science
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• v.100 no.3
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• pp.466-475
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• 2011

This study purposed to analyze the spatial pattern and the amount of carbon emission at the deforestation area based on the administrative and GIS data. The total size of deforestation area in last nine years (2000-2008) was about 649 ha, and it was occurred annually about 72 ha. The occurrence rate of deforestation per administrative area in Wonju was about 0.74%. It was 0.34% higher than that of Kwangwondo, and 0.06% less than that of National rate. On the other hand, the forms of deforestation by purpose were not related to the administrative district unit. The number of deforestation forms was highest at settlements. second most frequent form is other land. Grassland showed the lowest score. In addition, the deforestations were more occurred which is closed to the existing housing and building rather than roads. The number of deforestation was 1.2 times higher based on 300m. Seventy percent of deforestation was occurred which is less than 0.5 ha in size, and it increased to 91% when the size is less than 1ha. The total size of theoretical carbon emission based on deforestation area was estimated at 23,424 tc, and average annual carbon emission was estimated by 2,603 tc. Carbon emission per ha was 36.1 tC/ha. This study results will be useful to construct the greenhouse gas statistical verification system against the Post-2012 by GIS.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.244-247
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• 2003

Multi-temporal data is used to determine the rate of deforestation between the years 1976, 1987 and 2000. Three Landsat TM images, for each period, are pre-processed, mosaicked and normalized difference vegetation index (NDVI) values computed. Based on the values, totally non-forested areas are masked out. The forested areas, both partially and wholly, show a very high degree of correlation between all the bands (reflective), thus necessitating application of principal component analysis. The first two principal components and NDVI values (scaled to 0 ? 255) are used in K-means unsupervised classification to distinguish forest from non-forest areas (that appeared as forest at first). Comparison of the resulting thematic maps gives an annual deforestation rate of roughly 15 0000ha. or 2% between any two epochs.

• Journal of Environmental Science International
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• v.11 no.8
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• pp.773-781
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• 2002

The natural carbon cycle has been perturbed since the mid-19th century by anthropogenic CO$_2$emissions from fossil fuel combustion and deforestation due to population growth and industrialization. The current study simulated the global carbon cycle for the past 42 years using an eight-box carbon cycle model. The results showed that since the terrestrial biospheric carbon sink was roughly offset by the deforestation source, the fossil fuel emission source was partitioned between the atmospheric and oceanic sinks. However, the partitioning ratio between the atmosphere and the ocean exhibited a change, that is, the carbon accumulation rate was faster in the atmosphere than in the ocean, due to a decrease in the so-called ocean buffering capacity. It was found that the ocean buffering capacity to take up excess CO$_2$decreased by 50% in terms of the buffer factor over the past 42 years. Accordingly, these results indicate that if the current CO$_2$emission trend continues, the future rate of increase in the atmospheric CO$_2$concentration will accelerate.

• Journal of the Korea Furniture Society
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• v.18 no.4
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• pp.317-323
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• 2007

Almost all the people, particularly the rural people are directly dependent on the continued productivity of natural resources, like water, soils, forests and fisheries. But the overuse by the extremely high population pressures has degraded the natural resources into severe widespread deforestation. The degradation of natural resources, particularly the plant resources has been a great concern for socio-economic and sustainable development of the country. The Forests in Bangladesh have been depleted and degraded in volume, area, and quantity, thus requiring urgent forest protection by identifying the causes of forest loss. There are so many causes of deforestation and loss of genetic resources such as; the timber industry, which, legal or not, are cutting too many trees; indigenous forest dwellers, having their own types of problems; migrants, who, because of problems in their places of origin, have decided to move to the forests and the government through its Forest Department which is not able or willing to implement suitable policies to regulate the cutting trees and to prevent illegal cutting. Because it is a time consuming task to mitigate the first and second sets of factors, we recommend involving forest dwellers in forestry practices as much as possible and taking necessary steps to alleviate the third and fourth sets and thereby reduce the rate of forest depletion. Accordingly, a number of strategies that should be adopted to halt the loss of remaining forest cover are discussed.

• Korean Journal of Agricultural Science
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• v.47 no.4
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• pp.1083-1096
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• 2020

Global attention to the greenhouse gas emissions from deforestation and forest degradation is increasing. There is a growing recognition of reducing emission from deforestation and forest degradation plus (REDD+) as an effective way to reduce greenhouse gas emissions in the forestry sector. The Republic of Korea is implementing REDD+ pilot projects in four Southeast Asian countries as part of its efforts to reduce greenhouse gas emissions. This study evaluates countries with the potential to become priority partner countries for Korea's REDD+ programs, using the following five criteria: The first criterion is that a country should include the forest sector and REDD+ in its national plan for reducing greenhouse gas (GHG) emissions. The second and third criteria refer to an average forest coverage rate of over 44% and a forest change rate of over - 0.1%, among the countries with forest cover of more than 10 million ha. The fourth criterion is that the country should meet the Forest Reference Emission Level requirements, one of the four elements of the Warsaw REDD+ Framework. The fifth criterion is that the country should have bilateral relations with the Republic of Korea in forestry while at the same time be a partner country for cooperation on climate change as well as a REDD+ pilot country. Based on our evaluation, we conclude that the first priority countries are Indonesia, Cambodia, and Myanmar. The second priority countries include Brazil, Ecuador, and Peru. Finally, the third priority countries are Columbia, Congo, and Mozambique. This study suggests that for the selection of priority partner countries, Korean REDD+ programs should center on existing REDD+ pilot countries.

• Korean Journal of Environment and Ecology
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• v.29 no.5
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• pp.785-790
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• 2015

As an alternative to large-scale clear cutting silviculture, strip clear cutting (SC) is being considered as a system compatible with ecological conservation and forest regeneration. In South Korea, application and effectiveness of SCC in varying forest types were rarely found. In this study, under the subject of strip clear cutting lands of pinus densiflora forest at Samcheok, Gangwon-do Province, the developmental aspect of low vegetation prior to and after deforestation and the correlation between environmental factor and pine regeneration were analyzed. The cover rate of understory vegetation was appeared to be increased after deforestation and rapidly increased two years after deforestation, and it was evaluated to be affected by vigorous tree species and photophilic species. From the perspective of relative importance value, Quercus mongolica, Artemisia keiskeana, and Rubus crataegifolius that influence the cover rate showed the inclination of continuous growth. The diversity of species showed increment inclination as well due to introduction and settlement of early transient species. As a result of analyzing the correlation between vegetation and environmental factor and generation of pine tree size, the soil exposure rate, intensity of light, and canopy openness showed positive relationship, and the understory vegetation cover and woody debris cover rate showed negative relationship.