• Title/Summary/Keyword: forest cover

Search Result 673, Processing Time 0.028 seconds

Spatial Distribution of CO2 Absorption Derived from Land-Cover and Stock Maps for Jecheon, Chungbuk Province (토지피복도와 임상도를 이용한 제천시의 이산화탄소 분포 추정)

  • Jeon, Jeong-Bae;Na, Sang-Il;Yoon, Seong-Soo;Park, Jong-Hwa
    • Journal of Korean Society of Rural Planning
    • /
    • v.19 no.2
    • /
    • pp.121-128
    • /
    • 2013
  • The greenhouse gas emission according to the energy consumption is the cause of global warming. With various climates, it is occurs the direct problems to ecosystem. The various studies are being to reduce the carbon dioxide, which accounts for more than 80% of the total greenhouse gas emissions. In this study, estimate the carbon usage using potential biomass extracted from forest type map according to land-use by satellite image, and estimate the amount of carbon dioxide, according to the energy consumption of urban area. The $CO_2$ adsorption is extracted by the amount of forest based on the direct absorption of tree, the other used investigated value. The $CO_2$ emission in Jecheon was 3,985,900 $TCO_2$ by energy consumption. At the land cover classification, the forest is analyzed as 624,085ha and the farmland is 148,700ha. The carbon dioxide absorption was estimated at 1,834,850 Tons from analyzed forest. In case of farmland, it was also estimated at 706,658 Tons.

Understanding the LST (Land Surface Temperature) Effects of Urban-forests in Seoul, Korea

  • Kil, Sung-Ho;Yun, Young-Jo
    • Journal of Forest and Environmental Science
    • /
    • v.34 no.3
    • /
    • pp.246-248
    • /
    • 2018
  • Urban development and population have augmented the increase of impervious land-cover. This phenomenon has amplified the effects of climate change and increasing urban island effects due to increases in urban temperatures. Seoul, South Korea is one of the largest metropolitan cities in the world. While land uses in Seoul vary, land cover patterns have not changed much (under 2%) in the past 10 years, making the city a prime target for studying the effects of land cover types on the urban temperature. This research seeks to generalize the urban temperature of Seoul through a series of statistical tests using multi-temporal remote sensing data focusing on multiple scales and typologies of green space to determine its overall effectiveness in reducing the urban heat. The distribution of LST values was reduced as the size of urban forests increased. It means that changing temperature of large-scale green-spaces is less influenced because the broad distribution could be resulted in various external variables such as slope aspect, topographic height and density of planting areas, while small-scale urban forests are more affected from that. The large-scale green spaces contributed significantly to lowering urban temperature by showing a similar mean LST value. Both of concentration and dispersal of urban forests affected the reduction of urban temperature. Therefore, the findings of this research support that creating urban forests in an urban region could reduce urban temperature regardless of the scale.

Ecological responses of natural and planted forests to thinning in southeastern Korea: a chronosequence study

  • Cho, Yong-Chan;Pee, Jung-Hun;Kim, Gyeong-Soon;Koo, Bon-Yoel;Cho, Hyun-Je;Lee, Chang-Seok
    • Journal of Ecology and Environment
    • /
    • v.34 no.4
    • /
    • pp.347-355
    • /
    • 2011
  • Effects of forest thinning on community level properties have not been understood yet in Korea. We investigated regeneration patterns and trajectories after a disturbance by applying a chronosequence approach. Light availability, litter and woody debris cover, and species composition were determined for twenty 50 m line-transect samples representing a disturbance duration gradient (within 11 years). Environmental factors such as light availability and coverage of woody debris and litter changed abruptly after thinning and then returned to the pre-disturbance state. Although species richness was gained at shrub and ground layer in a limited way in both forests, cover of various functional types revealed diversity in their responses. Notably, Alnus firma stands exhibited a larger increment of cover in woody plants. Ordination analysis revealed different regeneration trajectories between natural and planted stands. Based on ordination analysis, rehabilitated stands showed movement to alternative states compared with natural ones, reflecting lower resilience to perturbation (i.e., lower stability). Our results suggest that community resilience to artificial thinning depends on properties of the dominant species. But to get more explanatory ecological information, longer-term static observations are required.

NDVI RESPONSES TO THE FOREST CANOPY AND FLOOR IN EASTERN SIBERIA

  • Suzuki, Rikie;Kobayashi, Hideki;Delbart, Nicolas;Hiyama, Tetsuya;Asanuma, Jun
    • Proceedings of the KSRS Conference
    • /
    • 2007.10a
    • /
    • pp.325-328
    • /
    • 2007
  • We discuss the Normalized Difference Vegetation Index (NDVI) of the forest canopy and floor separately based on airborne spectral reflectance measurements and simultaneous airborne land surface images acquired around Yakutsk, Siberia in 2000. The aerial land surface images were visually classified into four forest types: no-green canopy and snow floor (Type-1), green canopy and snow floor (Type-2), no-green canopy and no-snow floor (Type-3), and green canopy and no-snow floor (Type-4). The mean NDVI was calculated for these four types. Although Type-2 had green canopy, the NDVI was rather small (0.17) because of high reflection from the snow cover on the floor. Type-3, which had no green canopy, indicated considerably large NDVI (0.45) due to the greenness of the floor. Type-4 had the largest NDVI (0.75) because of the greenness of both the canopy and floor. These results reveal that the NDVI depends considerably on forest floor greenness and snow cover in addition to canopy greenness.

  • PDF

Assessment on Forest Resources Change using Permanent Plot Data in National Forest Inventory (국가산림자원조사 고정표본점 자료를 활용한 산림자원변화 평가에 관한 고찰)

  • Yim, Jong-Su;Kim, Eun Sook;Kim, Chel Min;Son, Yeong Mo
    • Journal of Korean Society of Forest Science
    • /
    • v.104 no.2
    • /
    • pp.239-247
    • /
    • 2015
  • Since 2006, new national forest inventory in Korea has been restructured to assess current status and and monitor the changes in forest resources based on permanent sample plots. The objective of estimate this study is to assess changes in forest resources such as land use/cover categories and forest stand variables. For this study, permanent plot data were collected between 2006-2008 and 2011-2013 in Chungcheongbuk-do, respectively. In order to produce land use/cover change matrix which plays an important role as an activity data for estimating GreenHouse Gas inventory, permanent plots were classified into six land use/cover categories. Additionally, matrixes for assessing the changes in age class and dominant tree species can provide more detailed information. For forest stand variables(tree density, basal area, growing stock, mean diameter at breath height, and mean height), their growth and change were assessed. The periodic annual growth ratios for tree density and basal area were slightly declined whereas that of growing stock was estimated to be about 3.7%. The uncertainty of changes in forest stand variables is less than 5%, except for tree density (RSE: 58%). The variation of tree density is relatively high compared to the other variables.

Application of Remote Sensing and Geographic Information System in Forest Sector (원격탐사와 지리정보시스템의 산림분야 활용)

  • Lee, Woo-Kyun;Kim, Moonil;Song, Cholho;Lee, Sle-gee;Cha, Sungeun;Kim, GangSun
    • Journal of Cadastre & Land InformatiX
    • /
    • v.46 no.2
    • /
    • pp.27-42
    • /
    • 2016
  • Forest accounts for almost 64 percents of total land cover in South Korea. For inventorying, monitoring, and managing such large area of forest, application of remote sensing and geographic information system (RS/GIS) technology is essential. On the basis of spectral characteristics of satellite imagery, forest cover and tree species can be classified, and forest cover map can be prepared. Using three dimensional data of LiDAR(Light Detection and Ranging), tree location and tree height can be measured, and biomass and carbon stocks can be also estimated. In addition, many indices can be extracted using reflection characteristics of land cover. For example, the level of vegetation vitality and forest degradation can be analyzed with VI (vegetation Index) and TGSI (Top Grain Soil Index), respectively. Also, pine wilt disease and o ak w ilt d isease c an b e e arly detected and controled through understanding of change in vegetation indices. RS and GIS take an important role in assessing carbon storage in climate change related projects such as A/R CDM, REDD+ as well. In the field of climate change adaptation, impact and vulnerability can be spatio-temporally assessed for national and local level with the help of spatio-temporal data of GIS. Forest growth, tree mortality, land slide, forest fire can be spatio-temporally estimated using the models in which spatio-temporal data of GIS are added as influence variables.

Mapping Distribution of Dipterocarpus in East Kalimantan, Indonesia

  • Aoyagi, Kota;Tsuyuki, Satoshi;Phua, Mui-How;Teo, Stephen
    • Journal of Forest and Environmental Science
    • /
    • v.28 no.3
    • /
    • pp.179-184
    • /
    • 2012
  • Dipterocarps (Dipterocarpaceae) is a dominant tree family of tropical rainforest in Southeast Asia. Dipterocarps have been exploited for its timber and disappearing fast in East Kalimantan. In this study, we predicted the distribution of dipterocarpus, one of the main dipterocarps genera, by evaluating its habitat suitability using logistic regression analysis with specimen collection points and environmental factors from GIS data. Current distribution of dipterocarpus was generated by combining the habitat suitability classes with an updated forest cover map. Rainfall, soil type, followed by elevation was the main factors that influence the distribution of dipterocarpus in East Kalimantan. Dipterocarpus can be found in a quarter of the current forest cover, which is highly suitable as habitat of Dipterocarpus.

Application study of random forest method based on Sentinel-2 imagery for surface cover classification in rivers - A case of Naeseong Stream - (하천 내 지표 피복 분류를 위한 Sentinel-2 영상 기반 랜덤 포레스트 기법의 적용성 연구 - 내성천을 사례로 -)

  • An, Seonggi;Lee, Chanjoo;Kim, Yongmin;Choi, Hun
    • Journal of Korea Water Resources Association
    • /
    • v.57 no.5
    • /
    • pp.321-332
    • /
    • 2024
  • Understanding the status of surface cover in riparian zones is essential for river management and flood disaster prevention. Traditional survey methods rely on expert interpretation of vegetation through vegetation mapping or indices. However, these methods are limited by their ability to accurately reflect dynamically changing river environments. Against this backdrop, this study utilized satellite imagery to apply the Random Forest method to assess the distribution of vegetation in rivers over multiple years, focusing on the Naeseong Stream as a case study. Remote sensing data from Sentinel-2 imagery were combined with ground truth data from the Naeseong Stream surface cover in 2016. The Random Forest machine learning algorithm was used to extract and train 1,000 samples per surface cover from ten predetermined sampling areas, followed by validation. A sensitivity analysis, annual surface cover analysis, and accuracy assessment were conducted to evaluate their applicability. The results showed an accuracy of 85.1% based on the validation data. Sensitivity analysis indicated the highest efficiency in 30 trees, 800 samples, and the downstream river section. Surface cover analysis accurately reflects the actual river environment. The accuracy analysis identified 14.9% boundary and internal errors, with high accuracy observed in six categories, excluding scattered and herbaceous vegetation. Although this study focused on a single river, applying the surface cover classification method to multiple rivers is necessary to obtain more accurate and comprehensive data.

Monitoring of Deforestation and Fragmentation in Sarawak, Malaysia between 1990 and 2009 Using Landsat and SPOT Images

  • Kamlun, Kamlisa Uni;Goh, Mia How;Teo, Stephen;Tsuyuki, Satoshi;Phua, Mui-How
    • Journal of Forest and Environmental Science
    • /
    • v.28 no.3
    • /
    • pp.152-157
    • /
    • 2012
  • Sarawak is the largest state in Malaysia that covers 37.5% of the total land area. Multitemporal satellite images of Landsat and SPOT were used to examine deforestation and forest fragmentation in Sarawak between 1990 and 2009. Supervised classification with maximum likelihood classifier was used to classify the land cover types in Sarawak. The overall accuracies of all classifications were more than 80%. Our results showed that forests were reduced at 0.62% annually during the two decades. The peat swamp forest suffered a tremendous loss of almost 50% between 1990 and 2009 especially at coastal divisions due to intensified oil palm plantation development. Fragmentation analysis revealed the loss of about 65% of the core area of intact forest during the change period. The core area of peat swamp forest had almost completely disappeared during the two decades.

Temporal and Spatial Cumulative Impact Assessments on Forest Damages by Housing Development Projects (택지개발사업이 산림에 미치는 시·공간적 누적영향 분석)

  • Lee, Dong-Kun;Kim, Eun-Young;Oh, Kyu-Shik;Yoon, So-Won
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.9 no.6
    • /
    • pp.107-116
    • /
    • 2006
  • Recently, it has been important not only to evaluate environmental effects but also to assess cumulative and comprehensive effects by the development projects. This paper concentrates on temporal and spatial cumulative impacts on Suji district in Yongin, Gyunggi-do. This paper adopted two methods to assess the cumulative impacts. First, it assesses the temporal change of forest patch size and land cover according to the patch size. Second, it compares housing development zones with the neighborhood. The result of the research appears that the damage is very serious, especially in small forest. The Forest area is changed to farm land, most of them become to built-up area later. In addition, it is assessed that the secondary housing development projects did more harm than the initial one. By assessing the cumulative impacts on Suji district, this research suggests to minimize two kinds of solutions : comprehensive environmental assessments in regional unit and regulation on total forest quantity.