• Title/Summary/Keyword: Forest Cover

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Detection of Heat Change in Urban Center Using Landsat Imagery (Landsat 영상을 이용한 도심의 열변화 탐지)

  • Kang, Joon-Mook;Ka, Myung-Seok;Lee, Sung-Soon;Park, Joon-Kyu
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.28 no.2
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    • pp.197-206
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    • 2010
  • Recently, developed countries have continuously been trying to recognize many issues about heat island in urban area and to make up countermeasures for them. This research is designed to extract change of land cover in the area under condition of land development with satellite images and to analyze its effect on the heat change in there. Heat change upon change of land cover in daejeon was analyzed with the four Landsat satellite images taken in April 1985, August 1994, May 2001, and May 2009. In order to measure the temperature on the surface in the city, the land surface temperature was produced with Landsat TM Band 6. Heat change is to detected with it. As a result, The urban area has been increased up to 23.59 percent. On the other hand, the forest area has been decreased up to 27.91%. Due to the urbanization, the temperature on the surface in urban center was higher than surrounding area. In that case, the temperature of urban center area was higher 2.4 to $5.7^{\circ}C$ compared with the forest area.

A Study on Effects of Vegetative Cover on Atmospheric Purification in Seoul, Korea (서울시 도시녹지의 대기정화효과)

  • Cho, Yong-Hyeon;Jo, Hyun-Kil
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.5 no.4
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    • pp.51-60
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    • 2002
  • This study quantified $CO_2$, $SO_2$ and $NO_2$ uptake by vegetation in Seoul. The natural area was only 20% of the area of Seoul and its tree-age structure was dominated by a young and growing tree population. However the natural area accounted for about 65%, 60%, and 59% of total $CO_2$, $SO_2$ and $NO_2$ uptake relatively. In natural area broad-leaved forest was dominative and accounted for about 37.8%, 36.7%, 36.6% of total $CO_2$, $SO_2$ and $NO_2$ uptake in Seoul relatively. In urbanized area the park type land use played an important role. It's area was only 17% of the urbanized area in Seoul, but it accounted for about 67%, 57%, and 56% of $CO_2$, $SO_2$ and $NO_2$ uptake in urbanized area relatively. Total annual uptake by vegetative cover was estimated as 446,741 ton/yr for $CO_2$, 314 ton/yr for $SO_2$ and 815 ton/yr for $NO_2$, and economic value of atmospheric purification for the entire area of Seoul amounted to approximately \228,073 millions/yr for the annual $CO_2$, $SO_2$ and $NO_2$ uptake. The results from this study are expected to be useful not merely in informing the public of atmospheric purification values of vegetative cover, but in urging the necessity for replanting and management budgets.

The Evaluation of on Land Cover Classification using Hyperspectral Imagery (초분광 영상을 이용한 토지피복 분류 평가)

  • Lee, Geun-Sang;Lee, Kang-Cheol;Go, Sin-Young;Choi, Yun-Woong;Cho, Gi-Sung
    • Journal of Cadastre & Land InformatiX
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    • v.44 no.2
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    • pp.103-112
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    • 2014
  • The objective of this study is to suggest the possibility on land cover classification using hyperspectal imagery on area which includes lands and waters. After atmospheric correction as a preprocessing work was conducted on hyperspectral imagery acquired by airborne hyperspectral sensor CASI-1500, the effect of atmospheric correction to a few land cover class in before and after atmospheric correction was compared and analyzed. As the result of accuracy of land cover classification by highspectral imagery using reference data as airphoto and digital topographic map, maximum likelihood method represented overall accuracy as 67.0% and minimum distance method showed overall accuracy as 52.4%. Also product accuracy of land cover classification on road, dry field and green house, but that on river, forest, grassland showed low because the area of those was composed of complex object. Therefore, the study needs to select optimal band to classify specific object and to construct spectral library considering spectral characteristics of specific object.

A Study on Deep Learning Optimization by Land Cover Classification Item Using Satellite Imagery (위성영상을 활용한 토지피복 분류 항목별 딥러닝 최적화 연구)

  • Lee, Seong-Hyeok;Lee, Moung-jin
    • Korean Journal of Remote Sensing
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    • v.36 no.6_2
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    • pp.1591-1604
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    • 2020
  • This study is a study on classifying land cover by applying high-resolution satellite images to deep learning algorithms and verifying the performance of algorithms for each spatial object. For this, the Fully Convolutional Network-based algorithm was selected, and a dataset was constructed using Kompasat-3 satellite images, land cover maps, and forest maps. By applying the constructed data set to the algorithm, each optimal hyperparameter was calculated. Final classification was performed after hyperparameter optimization, and the overall accuracy of DeeplabV3+ was calculated the highest at 81.7%. However, when looking at the accuracy of each category, SegNet showed the best performance in roads and buildings, and U-Net showed the highest accuracy in hardwood trees and discussion items. In the case of Deeplab V3+, it performed better than the other two models in fields, facility cultivation, and grassland. Through the results, the limitations of applying one algorithm for land cover classification were confirmed, and if an appropriate algorithm for each spatial object is applied in the future, it is expected that high quality land cover classification results can be produced.

Estimation of Carbon Stock in the Chir Pine (Pinus roxburghii Sarg.) Plantation Forest of Kathmandu Valley, Central Nepal

  • Sharma, Krishna Prasad;Bhatta, Suresh Prashad;Khatri, Ganga Bahadur;Pajiyar, Avinash;Joshi, Daya Krishna
    • Journal of Forest and Environmental Science
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    • v.36 no.1
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    • pp.37-46
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    • 2020
  • Vegetation carbon sequestration and regeneration are the two major parameters of forest research. In this study, we analyzed the vegetation carbon stock and regeneration of community-managed pine plantation of Kathmandu, central Nepal. Vegetation data were collected from 40 circular plots of 10 m radius (for the tree) and 1m radius (for seedling) applying a stratified random sampling and nested quadrat method. The carbon stock was estimated by Chave allometric model and estimated carbon stock was converted into CO2 equivalents. Density-diameter (d-d) curve was also prepared to check the regeneration status and stability of the plantation. A d-d curve indicates the good regeneration status of the forest with a stable population in each size class. Diversity of trees was very low, only two tree species Pinus roxburghii and Eucalyptus citriodora occurred in the sample plots. Pine was the dominant tree in terms of density, basal area, biomass, carbon stock and CO2 stock than the eucalyptus. The basal area, carbon stock and CO2 stock of forest was 33±1.0 ㎡ ha-1, 108±5.0 Mg ha-1 and 394±18 Mg ha-1, respectively. Seedling and tree density of the plantation was 4,965 ha-1 and 339 ha-1 respectively. The forest carbon stock showed a positive relationship with biomass, tree diameter, height and basal area but no relationship with tree density. Canopy cover and tree diameter have a negative effect on seedling density and regeneration. In conclusion, the community forest has a stable population in each size class, sequestering a significant amount of carbon and CO2 emitted from densely populated Kathmandu metro city as the forest biomass hence have a potentiality to mitigate the global climate change.

Outlook Analysis of Future Discharge According to Land Cover Change Using CA-Markov Technique Based on GIS (GIS 기반 CA-Markov 기법을 이용한 토지피복 변화에 따른 미래 유출량 전망 분석)

  • Park, Jin-Hyeog;No, Sun-Hee;Lee, Geun-Sang
    • Journal of the Korean Association of Geographic Information Studies
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    • v.16 no.3
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    • pp.25-39
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    • 2013
  • In this study, the change of the discharge according to the land cover change which acts as one of dominant factors for the outlook of future discharge was analyzed using SWAT(Soil and Water Assessment Tool) model for Yongdam and Daecheong Dam Watershed in the Geum River Basin. The land cover maps generated by Landsat TM satellite images in the past 1990 and 1995 were used as observed data to simulate the land cover in 2000 by CA-Markov serial technique and after they were compared and verified, the changes of land cover in 2050 and 2100 in the future were simulated. The discharge before and after the change of land cover by using input data of SWAT model was compared and analyzed under the A1B scenario. As a result of analyzing the trend in the elapses of year on the land cover in the Geum River Basin, the forest and rice paddy class area steadily decreased while the urban, bare ground and grassland classes increased. As a result of analyzing the change of discharge considering the future change of the land cover, it appeared that the discharge considering the change of land cover increases by 1.83~2.87% on the whole compared to the discharge not considering the change of land cover.

Assessment of Biomass and Carbon Stock in Sal (Shorea robusta Gaertn.) Forests under Two Management Regimes in Tripura, Northeast India

  • Banik, Biplab;Deb, Dipankar;Deb, Sourabh;Datta, B.K.
    • Journal of Forest and Environmental Science
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    • v.34 no.3
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    • pp.209-223
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    • 2018
  • We investigated tree composition, stand characteristics, biomass allocation pattern and carbon storage variability in Sal forests (Shorea robusta Garten.) under two forest management regimes (Sal forest and Sal plantation) in Tripura, Northeast India. The results revealed higher species richness (29 species), stand density of $1060.00{\pm}11.12stems\;ha^{-1}$ and diversity index ($1.90{\pm}0.08$) in Sal forest. and lower species richness (4 species), stand density of $ 230.00{\pm}37.22stems\;ha^{-1}$ and diversity index ($0.38{\pm}0.15$) in Sal plantation. The total basal cover $33.02{\pm}4.87m^2ha^{-1}$) and dominance ($0.76{\pm}0.08$) were found higher in Sal plantation than the Sal forest ($22.53{\pm}0.38m^2ha^{-1}$ and $0.23{\pm}0.02$ respectively). The total vegetation carbon density was recorded higher in Sal plantation ($219.68{\pm}19.65Mg\;ha^{-1}$) than the Sal forest ($167.64{\pm}16.73Mg\;ha^{-1}$). The carbon density estimates acquired in this study suggest that Sal plantation in Tripura has the potentiality to store a large amount of atmospheric carbon inspite of a very low species diversity. However, Sal forests has also an impending sink of carbon due to presence of large number of young trees.

Assessment of Above Ground Carbon Stock in Trees of Ponda Watershed, Rajouri (J&K)

  • Ahmed, Junaid;Sharma, Sanjay
    • Journal of Forest and Environmental Science
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    • v.32 no.2
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    • pp.120-128
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    • 2016
  • Forest sequesters large terrestrial carbon which is stored in the biomass of tree and plays a key role in reducing atmospheric carbon. Thus, the objectives of the present study were to assess the growing stock, above ground biomass and carbon in trees of Ponda watershed of Rajouri district (J&K). IRS-P6 LISS-III satellite data of October 2010 was used for preparation of land use/land cover map and forest density map of the study area by visual interpretation. The growing stock estimation was done for the study area as well as for the sample plots laid in forest and agriculture fields. The growing stock and biomass of trees were estimated using species specific volume equations and using specific gravity of wood, respectively. The total growing stock in the study area was estimated to be $0.25million\;m^3$ which varied between $85.94m^3/ha$ in open pine to $11.58m^3/ha$ in degraded pine forest. However in agriculture area, growing stock volume density of $14.85m^3/ha$ was recorded. Similarly, out of the total biomass (0.012 million tons) and carbon (0.056 million tons) in the study area, open pine forest accounted for the highest values of 43.74 t/ha and 19.68 t/ha and lowest values of 5.68 t/ha and 2.55 t/ha, respectively for the degraded pine forest. The biomass and carbon density in agriculture area obtained was 5.49 t/ha and 2.47 t/ha, respectively. In all the three forest classes Pinus roxburghii showed highest average values of growing stock volume density, biomass and carbon.

A Study on Forest Land Classification Using Multivariate Statistical Methods : A Case Study at Mt. Kwanak (다변수통계방법을 이용한 산지분류에 관한 연구)

  • 정순오
    • Journal of the Korean Institute of Landscape Architecture
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    • v.13 no.1
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    • pp.43-66
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    • 1985
  • Korea needs proper and rational public policies on conservation and use of forest land and other natural resources because of the accelerating expansion of national land developments in recent years. Unfortunately, there is no systematic planning system to support the needs. Generally, forest land use planning needs suitability analysis based on efficient land classification system. The goal of this study was to classify a forest land using multivariate satistical methods. A case study was carried out in winter of 1983 on a mountainous area higher than 100m above sea level located at Mt. Kwanak in Anyang -city, Kyung-gi-do (province). The study area was 19.80 km$^2$wide and was divided into 1, 383 Operational Taxonomic Units (OTU's) by a 120m$\times$120m grid. Fourteen descriptors were identified and quantified for each OTU from existing national land data : elevation, slope, aspect, terrain form, geologic material, surface soil permeability, topsoil type, depth of the solum, soil acidity, forest cover type, stand size class, stand age class, stand density class, and simple forest soil capability class. For this study, a FORTRAN IV program was written for input and output map data, and the computer statistics packages, SPSS and BMD, were used to perform the multivariate statistical analysis. Fourteen variables were analyzed to investigate the characteristics of their fire quench distribution and to estimate the correlation coefficients among them. Principal component analysis was executed to find the dimensions of forest land characteristics, and factor scores were used for proper samples of OTU throughout the study area. In order to develop the classes of forest land classification based on 102 surrogates, cluster and discriminant analyses of principal descriptor variable matrix were undertaken. Results obtained through a series of multivariate statistical analyses were as follows ; 1) Principal component analysis was proved to be a useful tool for data selection and identification of principal descriptor variables which represented the characteristics of forest land and facilitated the selection of samples.

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Habitat Analysis Study of Honeybees(Apis mellifera) in Urban Area Using Species Distribution Modeling - Focused on Cheonan - (종분포모형을 이용한 도시 내 양봉꿀벌 서식환경 분석 연구 - 천안시를 중심으로 -)

  • Kim, Whee-Moon;Song, Won-Kyong;Kim, Seoung-Yeal;Hyung, Eun-Jeong;Lee, Seung-Hyun
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.20 no.3
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    • pp.55-64
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    • 2017
  • The problem of the population number of honeybees that is decreasing not only domestically but also globally, has a great influence on human beings and the entire ecosystem. The habitat of honeybees is recognized to be superior in urban environment rather than rural environment, and predicting for habitat assessment and conservation is necessary. Based on this, we targeted Cheonan City and neighboring administrative areas where the distribution of agricultural areas, urban areas, and forest areas is displayed equally. In order to predict the habitat preferred by honeybees, we apply the Maxent model what based on the presence information of the species. We also selected 10 environmental variables expected to influence honeybees habitat environment through literature survey. As a result of constructing the species distribution model using the Maxent model, 71.7% of the training data were shown on the AUC(Area Under Cover) basis, and it was be confirmed with an area of 20.73% in the whole target area, based on the 50% probability of presence of honeybees. It was confirmed that the contribution of the variable has influence on land covering, distance from the forest, altitude, aspect. Based on this, the possibility of honeybee's habitat characteristics were confirmed to be higher in wetland environment, in agricultural land, close to forest and lower elevation, southeast and west. The prediction of these habitat environments has significance as a lead research that presents the habitat of honeybees with high conservation value of ecosystems in terms of urban space, and it will be useful for future urban park planning and conservation area selection.