• Journal of Forest and Environmental Science
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• 제28권3호
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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.

• 대한원격탐사학회지
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• 제27권3호
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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.

• 한국산림과학회지
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• 제101권3호
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• pp.365-373
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• 2012

본 연구는 원주시를 대상으로 중해상도 위성영상을 이용하여 산림전용지의 추출 및 정확도 분석을 목적으로 수행하였다. 2000년부터 2008년까지 산림에서 비산림으로 전용된 면적은 467 ha로 연평균 약 52 ha가 전용되었으며, 전용형태는 주거지로의 전용이 약 72% 차지하였으며, 전체발생면적의 약 97%가 2 ha 미만이였다. 또한, 산림전용지는 도로로부터 500 m이내와 산림 비산림 경계로부터 100 m이내 지역에서 약 79%가 발생하였다. 한편, 행정정보상의 산림전용지(GIS전용지)와 위성영상에 의하여 구축된 지수별(NDVI,NBR,NDWI) 산림전용지(RS전용지)와 비교한 결과, 추출정확도는 $3{\times}3$ 필터링을 적용한 NDVI의 평균$({\mu})$-표준편차$({\sigma}){\times}1.5$ 구간에서 일치율 35.47%, K-지수 0.20로 가장 안정적인 정확도를 나타냈다. 정확도 오차의 원인으로는 산림전용지의 토지이용변화와 토지피복변화의 불일치로서, 행정정보상의 산림전용지의 실제 토지피복변화율은 약 32%에 지나지 않았다. 또한, RS전용지에 의하여 산림경영활동지역의 약 7.52%가 산림전용지로 오류 추출되었다. 토지이용 및 토지피복상 변화된 산림전용지(GIS전용지2)를 대상으로 지수별 RS전용지와 정확도를 비교한 결과, $3{\times}3$ 필터링을 적용한 NDVI의 ${\mu}-{\sigma}{\times}2$ 구간에서 일치율 61.23%, K-지수 0.23으로 향상되었다.

• 한국지리정보학회지
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• 제11권2호
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• pp.108-120
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• 2008

본 연구에서는 행정정보, GIS, RS정보, 확률모델을 이용하여 교토의정서에서 정의하는 산림전용지역의 추출가능성에 대하여 검토하였다. 1989년의 정사사진과 2001년의 IKONOS화상을 이용한 산림전용지역의 특성을 보면, 1989년부터 2001년까지의 산림전용지역은 약 40ha로 나타났다. 산림전용지역의 종류를 살펴보면, 도로(임도) 개설 및 주택지 개발을 위한 산림전용이 대부분을 차지하였고, 택지전용지의 80%는 기존의 도로로부터 100m이내에 분포하였으며, 신설된 도로 또한 20% 이상이 기존의 도로로부터 100m이내에 분포하였다. 산림전용지역의 추출모델 구축을 위하여 지형인자와 위성영상인자를 이용하였으며, 확률 개념을 도입한 산림전용지 발생 확률 지도를 작성하였다. 구축한 산지전용지 발생 모델의 유효성을 검증하기 위하여, 대상지역을 시스템적으로 구분하여, 추출 정도를 비교 검토하였다. 베이즈 모델과 Regression모델을 비교한 결과, 베이즈모델이 Regression모델보다 높은 추출확률을 나타냈다. 모델의 적합성을 평가하기위해서 대상지역을 2지역으로 구분하여 한쪽의 정보만을 가지고 발생확률지도를 작성하고, 나머지 지역에 대하여 발생확률을 검토한 결과에서도 베이즈모델이 높은 추출확률을 나타냈다.

• 한국산림과학회지
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• 제100권3호
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• pp.466-475
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• 2011

본 연구는 산림전용정보와 GIS 정보를 상호 이용하여 산림전용지의 공간특성 분석과 함께 탄소배출량 파악을 목적으로 수행하였다. 최근 9년간(2000년부터 2008년까지) 산림에서 비산림으로 전용된 면적은 약 649 ha로, 연간 약 72 ha의 산림전용이 발생하였다. 행정구역 단위별 면적대비 전용발생률을 보면, 원주시는 약 0.74%로, 강원도 전용발생률보다는 0.34% 높게 나타났으나, 전국 전용발생률보다는 약 0.06%낮게 나타났다. 한편, 산림전용 목적별 형태는 행정구역 단위와 상관없이 유사하게 발생하였으며, 주거지, 기타 토지, 농경지, 초지의 순으로 나타났다. 또한, 산림전용은 기존 주택 및 건물로부터의 접근성이 도로로부터의 접근성보다 근접한 곳에서 발생하였으며, 300 m 기준으로는 약 1.2배정도 높게 발생하였다. 전체 산림전용발생의 70%는 0.5 ha미만의 지역에서 발생하였으며, 91%는 1 ha미만의 지역에서 발생하였다. 산림전용에 따른 총 탄소배출량은 약 23,424 tC이며, 연평균 2,603 tC로 나타났다. ha당 탄소배출량은 36.1 tC/ha로 나타났다. GIS에 의한 전용지의 공간특성을 파악함에 따라 Post-2012에 대비 온실가스 통계검증시스템 구축을 위한 기초적인 자료로서 유용하리라 생각된다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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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.

• 한국환경과학회지
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• 제11권8호
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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.

• 한국가구학회지
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• 제18권4호
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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.

• 농업과학연구
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• 제47권4호
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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.

• 한국환경생태학회지
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• 제29권5호
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• pp.785-790
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• 2015

대면적 개벌의 대안으로서, 대상 개벌은 생산림지의 생태 조건 보전과 임분 재생을 모두 고려하는 작업법이다. 그러나 우리나라에서는 대상 벌채 기법의 적용 및 효율성에 대한 연구를 찾아보기 어렵다. 본 연구는 강원도 삼척에서 2012년부터 2014년까지 소나무림 대상 벌채 (10m, 20m 및 40m) 처리 전 후의 하층식생 반응 및 소나무 재생과 임분 환경 변화와의 상관성을 방형구법을 적용하여 조사 및 분석하였다. 하층식생 피도 및 종다양성은 대상 벌채 넓이에 상관없이 교목 종 및 광선호 종의 확장에 의해 증가하는 경향이었고, 신갈나무, 맑은대쑥 및 산딸기 등의 벌채 후 잔존 교목 및 광선호 종들의 활발한 증가가 관찰되었다. 대상 벌채 구역의 소나무 정착은 수관층 환경 (광량 및 수관열림도) 및 토양나출도와는 정의 상관, 그리고 하층식생 및 임상 목질잔해물의 피도와는 음의 상관을 나타내었다.