• 제목/요약/키워드: Forest cover

검색결과 670건 처리시간 0.022초

공간DB엔진(SDE)을 이용한 수치임상도 운영·관리 프로그램 개발(Revision 1.0) (Development of the Program for Operating & Managing Digital Forest Cover Type Map Using SDE(Revision 1.0))

  • 유병오;서수안;류주형
    • 한국지리정보학회지
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    • 제14권3호
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    • pp.1-10
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    • 2011
  • 본 프로그램 개발의 목적은 기존의 아날로그 형태의 제작과정 및 공정 그리고 방대한 자료 관리의 문제점들을 해결하기 위해 SDE(spatial database engine) 라는 공간DB엔진을 이용하여 대량의 임상도를 운영 관리하는데 있다. 이를 위해 공간DB검색, 작업내용 및 진도파악, 인접 도엽간 검정/편집, 완료 도엽의 승인 및 반려 기능 등을 구현하여 일관된 운영 관리 표준화 공정을 확립하였다. 향후 본 프로그램을 활용하여 효율적인 임상도 제작과 대량의 임상도 보급이 가능할 것이며, 이에 따른 시간 및 비용을 절감할 수 있을 것으로 기대된다.

토지부문 온실가스 통계 산정을 위한 토지이용변화 평가방법 비교 (Comparison of Land-use Change Assessment Methods for Greenhouse Gas Inventory in Land Sector)

  • 박진우;나현섭;임종수
    • 한국기후변화학회지
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    • 제8권4호
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    • pp.329-337
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    • 2017
  • In this study, land-use changes from 1990 to 2010 in Jeju Island by different approaches were produced and compared to suggest a more efficient approach. In a sample-based method, land-use changes were analyzed with different sampling intensities of 2 km and 4 km grids, which were distributed by the fifth National Forest Inventory (NFI5), and their uncertainty was assessed. When comparing the uncertainty for different sampling intensities, the one with the grid of 2 km provided more precise information; ranged from 6.6 to 31.3% of the relative standard error for remaining land-use categories for 20 years. On the other hand, land-cover maps by a wall-to-wall approach were produced by using time-series Landsat imageries. Forest land increased from 34,194 ha to 44,154 ha for 20 years, where about 69% of total forest land were remained as forest land and 19% and 8% within forest lands were converted to grassland and cropland, respectively. In the case of grassland, only about 40% of which were remained as grassland and most of the area were converted to forest land and cropland. When comparing land-cover area by land-use categories with land-use statistics, forest areas were underestimated while areas of cropland and grassland were overestimated. In order to analyze land use change, it is necessary to establish a clear and consistent definition on the six land use classification.

Disturbance, Diversity, Regeneration and Composition in Temperate Forests of Western Himalaya, India

  • Tiwari, Om Prakash;Sharma, Chandra Mohan;Rana, Yashwant Singh;Krishan, Ram
    • Journal of Forest and Environmental Science
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    • 제35권1호
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    • pp.6-24
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    • 2019
  • We have investigated the impact of anthropogenic and natural disturbances on regeneration, composition and diversity in some temperate forests of Bhagirathi Catchment Area of Garhwal Himalaya. The forests were categorized on the basis of canopy cover and magnitude of disturbance into highly, moderately and least disturbed classes. The dominant tree species at lower elevation were Pinus roxburghii and Quercus leucotrichophora, while Abies pindrow, Q. semecarpifolia and Rhododenron arboreum were the dominant species at the upper elevational forests. Cythula tomentosa and Indegophera heterentha were the dominant shrub species present in all the forests. Similarly, Circium wallichii and Oxalis corniculata were the dominant herb species found in all forests (except Q. leucotrichophora forest), whereas Thalictrum foliolosum and Viola pilosa were noticed in each forest (except P. roxburghii forest). The tree density values oscillated between $400{\pm}10\;trees\;ha^{-1}$ to $750{\pm}89.1\;trees\;ha^{-1}$ which generally decreased from lower to higher disturbance regimes however, the total basal cover value was highest ($88.1{\pm}23.6m^2\;ha^{-1}$) in highly disturbed forest and lowest ($25.8{\pm}2.2m^2\;ha^{-1}$) in moderately disturbed forest. The shrub and herb densities were maximum in least disturbed forest, while the young regenerating individuals i.e., sapling and seedling were observed increasing from high to low disturbed forests which reflected that the forest fragmentation adversely affected the regeneration. However, A. pindrow and P. roxburghii were found invariably encroaching the habitats of R. arboreum and Q. leucotrichophora at various altitudes, respectively. The Canonical Correspondence Analysis clearly indicated that the elevation and lopping intensity have more impact on trees, while shrub and herbs were more influenced by elevation, canopy cover, light attenuation and soil erosion. Pinus roxburghii was the only species which was affected by heavy litter removal and forest fire.

울진지역 산불피해지의 산림피복형별 식생구조의 초기 변화 특성 (The Characteristics of Early Changes in Vegetation Structure by Forest Cover Type after Forest Fire Damage in Uljin region)

  • 김태운;한영섭;이성호;임채영;허태철;임창균;길민경;박준형
    • 한국환경복원기술학회지
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    • 제27권3호
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    • pp.1-18
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    • 2024
  • The study aims to establish a direction for forest ecological restoration by classifying forest types and understanding the ecological characteristics of the Uljin forest area damaged by a large fire in 2022. Hierarchical cluster analysis and indicator species analysis were conducted on 78 survey plots located in the forest fire-affected area, and four forest cover types were derived: P. densiflora pure forests, P. densiflora dominant forests, mixed broad-leaved forests, and Q. variabilis dominant forests. As a result of visually comparing changes in forest types before and after forest fire damage, by classifying data according to whether or not upper dead trees are included, it was confirmed that pine forests, which have a high proportion of pine trees, spread widely due to forest fire damage. However, broad-leaved mixed forests and oyster oak dominant forests showed characteristics of maintaining concentration, indicating that pine forests were severely damaged. As a result of the important value analysis, during the process of natural recovery after a forest fire, the species that appear early in the lower layer are the sprouts of existing species such as Quercus mongolica Fisch. ex Ledeb., Quercus variabilis Blume, Fraxinus sieboldiana Blume, Rhododendron mucronulatum Turcz. The distribution of diameter at breast height by forest cover type showed that among areas with extreme forest fire damage, the proportion of dead trees was relatively high and structural changes were large in P. densiflora pure forests and P. densiflora dominant forests where pine trees had a high distribution ratio. However, if continuous monitoring is carried out in the future with reference to the results of this study and plant data is collected and analyzed from a mid- to long-term perspective, it is believed that it will be used as useful data to promote forest ecological restoration projects in forest fire-affected areas.

Evaluation of a Land Use Change Matrix in the IPCC's Land Use, Land Use Change, and Forestry Area Sector Using National Spatial Information

  • Park, Jeongmook;Yim, Jongsu;Lee, Jungsoo
    • Journal of Forest and Environmental Science
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    • 제33권4호
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    • pp.295-304
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    • 2017
  • This study compared and analyzed the construction of a land use change matrix for the Intergovernmental Panel on Climate Change's (IPCC) land use, land use change, and forestry area (LULUCF). We used National Forest Inventory (NFI) permanent sample plots (with a sample intensity of 4 km) and permanent sample plots with 500 m sampling intensity. The land use change matrix was formed using the point sampling method, Level-2 Land Cover Maps, and forest aerial photographs (3rd and 4th series). The land use change matrix using the land cover map indicated that the annual change in area was the highest for forests and cropland; the cropland area decreased over time. We evaluated the uncertainty of the land use change matrix. Our results indicated that the forest land use, which had the most sampling, had the lowest uncertainty, while the grassland and wetlands had the highest uncertainty and the least sampling. The uncertainty was higher for the 4 km sampling intensity than for the 500 m sampling intensity, which indicates the importance of selecting the appropriate sample size when constructing a national land use change matrix.

고해상도 항공 영상과 딥러닝 알고리즘을 이용한 표본강도에 따른 토지이용 및 토지피복 면적 추정 (Assessing the Impact of Sampling Intensity on Land Use and Land Cover Estimation Using High-Resolution Aerial Images and Deep Learning Algorithms)

  • 이용규;심우담;이정수
    • 한국산림과학회지
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    • 제112권3호
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    • pp.267-279
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    • 2023
  • 본 연구는 IPCC에서 제시하고 있는 Approach 3 수준의 토지이용 및 토지피복 면적 추정을 위해 고해상도 항공사진에 딥러닝 알고리즘과 Sampling method를 적용하였으며, 표본강도에 따라 토지피복 면적을 산출하고 최적의 표본강도를 도출하는 것을 목적으로 하였다. 원격탐사자료로는 51 cm급의 고해상도 칼라 항공 이미지를 사용하였으며, 딥러닝 알고리즘은 전이 학습이 적용된 VGG16 아키텍처를 활용하였다. 딥러닝 기반 토지피복 분류모델의 학습과 검증은 육안판독을 통해 선별된 데이터를 이용하였다. 최적의 표본강도를 도출하기 위한 평가는 7개의 표본강도(4 × 4 km, 2 × 4 km, 2 × 2 km, 1 × 2 km, 1 × 1 km, 500 × 500 m, 250 × 250 m)에 따른 토지이용 및 토지피복 면적을 추정하고 환경부에서 제시한 토지피복지도와 비교하였다. 본 연구 결과, 딥러닝 기반의 토지피복 분류 모델의 전체정확도와 카파계수는 각각 91.1% 와 88.8%였다. F-Score는 초지를 제외한 모든 범주가 90% 이상으로 구축되어 모델의 정확도가 우수하였다. 표본강도별 적합도 검정은 유의수준 0.1에서 4 × 4 km를 제외한 모든 표본강도에서 환경부에서 제시한 토지피복지도의 면적 비율과 유의한 차이를 보이지 않았다. 또한, 표본강도가 증가할수록 상대표준오차와 상대효율은 감소하였으며, 상대표준오차는 1 × 1 km 표본강도에서 모든 토지피복범주가 15% 이하로 감소하였다. 따라서, 지역 단위의 토지피복 면적 산정을 위해서는 표본강도를 1 × 1 km보다 상세하게 설정하는 것이 적합하다고 판단된다.

경상북도 신갈나무 성숙림에서 15% 군상잔존벌 이후 초기 하층식생 변화 (Initial Responses of Understory Vegetation to 15% Aggregated Retention Harvest in Mature Oak (Quercus mongolica) Forest in Gyungsangbukdo)

  • ;김준수;조용찬;배상원;윤충원;변봉규;배관호
    • 한국산림과학회지
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    • 제102권2호
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    • pp.239-246
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    • 2013
  • 본 연구에서는 15% 군상잔존벌채의 식생 및 종다양성 보전 효과를 분석하기 위하여 경상북도 봉화군 신갈나무 성숙림(임령 100년 이상)에서 처리 전 후 조사를 통하여 직접적인 식생 변화를 관찰하였다. 벌채구(0.85), 잔존구(0.15) 및 대조구(1.0)에 1의 초본방형구를 각각 192개, 36개, 300개 설치한 후 하층식생의 피도 및 종다양성의 변화, 초본 및 목본의 생육형별 변화, 그리고 군집 변화(서열분석)등을 분석하였다. 서열분석 결과, 잔존구는 벌채구와 비교하여 전체적인 식생 속성 변화가 낮게 나타났다. 처리 직후, 벌채구는 기계적 피해에 의해 피도가 약간 감소(15.6%에서 14.7%)하였으며, 종풍부도(14종에서 22종)는 증가하였다. 잔존구 및 대조구는 피도 및 종풍부도 모두 증가하였다. 생육형 측면에서 15% 잔존벌채 이후 초기변화는 목본성 종 보다는 초본성 종의 양 증가에 영향을 미치는 것으로 나타났다. 처리 이후, 잔존구는 가장자리 증가에 의한 환경 변화 및 그에 따른 반응을 나타냈고, 벌채구는 벌채교란에 기인한 기계적 피해를 포함한 임분 구조 변화에 의한 반응이 나타났다. 본 연구는 임분 처리 전 자료를 수집하여 진행되고 있다는 점에서 지속적 관찰의 필요성이 높다.

인공강우실험에 의한 임도노면의 지표유출량 및 토양유실량 평가 (Predicting Surface Runoff and Soil Erosion from an Unpaved Forest Road Using Rainfall Simulation)

  • 유송;;이은재;임상준
    • 한국환경복원기술학회지
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    • 제18권3호
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    • pp.13-22
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    • 2015
  • Unpaved forest roads are common accessways in mountain areas being used for forestry purposes. The presence of forest roads produces large volumes of surface runoff and sediment yield due to changes in soil properties and hillslope profile. Rainfall simulation experiments were conducted to estimate the impacts of above-ground vegetation and antecedent soil water condition on hydrology and sediment processes. A total of 9 small plots($1m{\times}0.5m$) were installed to represent different road surface conditions: no-vegetation(3 plots), vegetated surface(3 plots), and cleared vegetation surface(3 plots). Experiments were carried out on dry, wet, and very wet soil moisture conditions for each plot. Above ground parts of vegetation on road surface influenced significantly on surface runoff. Runoff from no-vegetation roads(39.24L) was greater than that from vegetated(25.05L), while cleared-vegetation condition is similar to no-vegetation roads(39.72L). Runoff rate responded in a similar way to runoff volume. Soil erosion was also controlled by land cover, but the magnitude is little than that of surface runoff. Even though slight differences among antecedent soil moisture conditions were found on both runoff and soil erosion, runoff rate and soil losses were increased in very wet condition, followed by wet condition. The experiments suggest that vegetation cover on forest road surface seems most effective way to reduce surface runoff and soil erosion during storm periods.

Assessment of Vegetation Recovery after Forest Fire

  • Yu, Xinfang;Zhuang, Dafang;Hou, Xiyong
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.328-330
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    • 2003
  • The land cover of burned area has changed dramatically since Daxinganling forest fire in Northeastern China during May 6 ? June 4, 1987. This research focused on determining the burn severity and assessment of forest recovery. Burned severity was classified into three levels from June 1987 Landsat TM data acquired just after the fire. A regression model was established between the forest canopy closure from 1999 forest stand map and the NDVI values from June 2000 Landsat ETM+ data. The map of canopy closure was got according to the regression model. And vegetation cover was classified into four types according to forest closure density. The change matrix was built using the classified map of burn severity and vegetation recovery. Then the change conversions of every forest type were analyzed. Results from this research indicate: forest recovery status is well in most of burned scars; and vegetation change detection can be accomplished using postclassification comparison method.

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충주시 학교외부공간 피복유형에 따른 온열환경 및 생태면적률 비교 (Comparison of Thermal Environment and Biotope Area Rate according to Land Cover Types of Outside Space of School located in Chung-ju)

  • 주진희;반종현;윤용한
    • 한국환경과학회지
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    • 제19권9호
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    • pp.1103-1108
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    • 2010
  • This study was conducted to be used as basic data of environmental friendly construction planning by comparing and analyzing thermal environment, find particles and biotope area rate according to land cover types of outside space of schools located in Chung-ju. When meteorological factors were analyzed according to land cover types, for temperature planting area and paved area showed low-and high-temperature ranges, respectively, and relative humidity was negatively related with temperature as low-and high-temperature ranges corresponded to high-and low-humidity ranges, respectively. For Wet Bulb Globe Temperature Index (WBGT) by land cover types, it was observed to be artificial grass> bare land> natural grass. Find particles were different according to land cover types of playground with being bare land> artificial grass> natural grass in the order. Bare land playground, where there were artificial factors and no absorption of fine particles through stomata of leaves as a function of natural circulation, recorded the highest level of $39.8\;{\mu}g/m^3$ and the level was relatively higher compared to the levels by season in Chung-ju. Biotope area rate showed the order of M elementary school> K elementary school> C commercial high school. That was considered to be caused by the difference of land cover type of school playground accounting for a large part of a school.