• Title/Summary/Keyword: cropland areas

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Species richness related to landscape characteristics of uninhabited islands in Korea

  • Rho, Paikho
    • Journal of Ecology and Environment
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    • v.33 no.2
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    • pp.105-114
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    • 2010
  • The principal objective of this study was to characterize the relationships between geographical conditions (e.g., island area, distance to mainland) and landscape structures of uninhabited islands, and to evaluate the effects of islands and their landscape structures on species richness. One hundred randomly selected islands and 5,000 m buffered areas derived from the boundaries of each island were used to summarize the number of observed bird species, and landscape pattern indices, particularly patch density, edge density, shape index, and mean nearest neighboring distance. Spatial arrangements of individual patch type at the class level, which are markedly affected by the distance from an island to the mainland, have a superior ability to explain the variances in species richness, as compared to the geographical conditions and landscape pattern indices at the landscape level. The results demonstrate that the patch type landscape structure is the primary factor affecting species richness, as well as the distance to the mainland. In particular, landscape pattern indices of cropland/pasture and woody cover are statistically significant in terms of explaining species richness, which suggests that food resources and appropriate conditions in landscape structures of habitat types are assumed as important elements in attracting bird species. This study also proposes the importance of evaluation on the landscape structure of each island, in order to designate protected areas and to establish a management plan for species conservation in uninhabited islands.

Land-use Change Assessment by Permanent Sample Plots in National Forest Inventory (국가산림자원조사 고정표본점 자료를 이용한 토지이용변화 평가)

  • Yim, Jong-Su;Kim, Rae Hyun;Lee, Sun Jeoung;Son, Yeong Mo
    • Journal of Climate Change Research
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    • v.6 no.1
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    • pp.33-40
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    • 2015
  • Forests are to be recognized as an important carbon sink under the UNFCCC that consist of above- and below-biomass, dead organic matter (DOM) such as dead wood and litter, and soil organic matter (SOM). In order to asses for DOM and SOM, however, it is relevant to land-use change matrices over last 20 years for each land-use category. In this study, a land-use change matrix was produced and its uncertainty was assessed using a point sampling technique with permanent sample plots in national forest inventory at Chungbuk province. With point sampling estimated areas at 2012 year for each land-use category were significantly similar to the true areas by given six land-use categories. Relative standard error in terms of uncertainty of land-use change among land-use categories ranged in 4.3~44.4%, excluding the other land. Forest and cropland covered relatively large areas showed lower uncertainty compared to the other land-use categories. This result showed that selected permanent samples in the NFI are able to support for producing land-use change matrix at a national or province level. If the $6^{th}$ NFI data are fully collected, the uncertainty of estimated area should be improved.

Land Surface Temperature Dynamics in Response to Changes in Land Cover in An-Najaf Province, Iraq

  • Ebtihal Taki, Al-Khakani;Watheq Fahem, Al-janabi
    • Korean Journal of Remote Sensing
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    • v.39 no.1
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    • pp.99-110
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    • 2023
  • Land surface temperature (LST) is a critical environmental indicator affected by land cover (LC) changes. Currently, the most convenient and fastest way to retrieve LST is to use remote sensing images due to their continuous monitoring of the Earth's surface. The work intended to investigate land cover change and temperature response inAn-Najaf province. Landsat multispectral imageries acquired inAugust 1989, 2004, and 2021 were employed to estimate land cover change and LST responses. The findings exhibited an increase in water bodies, built-up areas, plantations, and croplands by 7.78%, 7.27%, 6.98%, 3.24%, and 7.78%, respectively, while bare soil decreased by 25.27% for the period (1989-2021). This indicates a transition from barren lands to different land cover types. The contribution index (CI) was employed to depict how changes in land cover categories altered mean region surface temperatures. The highest LSTs recorded were in bare lands (42.2℃, 44.25℃, and 46.9℃), followed by built-up zones (41.6℃, 43.96℃, and 44.89℃), cropland (30.9℃, 32.96℃, and 34.76℃), plantations (35.4℃, 36.97℃, and 38.92℃), and water bodies (27.3℃, 29.35℃, and 29.68℃) respectively, in 1989, 2004, and 2021. Consequently, these changes resulted in significant variances in LST between different LC types.

Geographical features and types and changes of agricultural land uses in North Korea

  • Lee, Kyo-Suk;Ryu, Jin-Hee;Lee, Dong-Sung;Hong, Byeong-Deok;Seo, Il-Hwan;Kim, Sung Chul;Chung, Doug-Young
    • Korean Journal of Agricultural Science
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    • v.46 no.1
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    • pp.205-217
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    • 2019
  • The aim of this study was to identify land resources because food production and supply in North Korea have been at risk due to variations in its seasonal climate. More than three-fifths of the soils are locally derived from the weathering of granitic rocks or various kinds of schists developed from crystalline rocks. Well-developed reddish brown soils derived from limestone are found in the North Hwanghae province and in the southern part of the South Pyeongan province. Additionally, a narrow strip of similarly fertile land runs through the eastern seaboard of the Hamgyong and Kangwon Provinces. The loss of clay particles and organic matter are major causes of degradation in the soil physical and chemical properties in North Korea. 75% of the areas converted from forests became croplands, and 69% of the land converted to croplands came from forests. The net forest loss was quite small from the 1990s to the 2000s. However, deforestation in areas with a slightly lower elevation and gentler slope between 1997 and 2014 led to severe soil erosion resulting in a drastic change in the physical and chemical properties of the soil which influenced cropland stability and productivity. Therefore, the drastic changes in land cover as well as in the physical and chemical properties of the soil caused by various geographical features have seriously influenced the productivity of crops in North Korea.

A Study on Environmental Problems by the Changes of the Population and Agriculture in North Korea (북한의 인구와 농업의 변화에 따른 환경문제 연구)

  • Lee, Min-Boo;Kim, Nam-Shin;Jin, Shizhu
    • Journal of the Korean association of regional geographers
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    • v.14 no.6
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    • pp.709-717
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    • 2008
  • This study is to analyze environmental problems which have caused by changes of the population and agriculture in North Korea. Main results of the research are following. First, Population of the North Korea shows lower increase ratio less than 2% growth from 1970's to middle of 1990's. This is interpreted by food shortages. Second, population distribution by provinces represented that northern and eastern part of the North Korea were comparatively lower and other western areas were higher. Third, Food situation of the North Korea was relatively better in 1970's, but, 1990's was the worst in the way. Fourth, on the agricultural productivity according to each province, western areas possessing more plains were more higher than mountainous areas of the northern and eastern parts of North Korea. Fifth, Growth ratio of food production and population have grown very steadily until 1990's, but the increase ratio of population exceeded food productivity after 1990's. Sixth, Cropland reclamation for improving these situation have caused deforestation and environmental problems and especially eastern and northern areas became more serious. For the solving these problems of North Korea, it is necessary to get the help of South Korea and international societies with efforts by itself.

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Analysis of Soil Erosion Hazard Zone by Cropland (농경지 토양침식 위험지역 분석)

  • Kim, Kyung-Tak;Kim, Joo-Hun
    • Journal of Wetlands Research
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    • v.7 no.1
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    • pp.107-117
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    • 2005
  • Soil erosion is influenced from a variety of factors such as rainfall distribution, soil type, land use, etc. This paper is aimed at analyzing the soil erosion hazard zone in cropland. RUSLE was used for an analysis of soil erosion amount, and for the spatial data of basin, soil erosion amount was calculated by extracting the respect topography space related factors of RUSLE using DEM, Landuse, Soil map as base map. This paper is targeting at the watershed of Gyeongan stream in Gyeonggi-do The result of an analysis of soil erosion amount showed that soil erosion occurred in the order of crop field(1210) planting area, orchard(1220), non-adjusted paddy fields(1120), and adjusted paddy fields(1110), and also the average soil erosion in these planting areas has the most amount in crop field planting area. As a result of analysis on soil erosion hazard zone of farm land by classifying it into 5 classes using the result of that result of analysis on the amount of soil erosion, in case of Class 5 in which the hazard of soil erosion is the highest, approximately 72.5ha that corresponds to 2.4% of the total farm land was decided as erosion hazard zone. For this erosion hazard zone, it was analyzed that dry field crop planting area was 72.4ha and orchard was 0.1ha, and Class 5 hazard zone did not appear in other farming areas. Also, it showed that Class II(1~50ton/ha/yr) area had the most ratio of the entire farm land, i.e., 70.2%, regardless of land use state. According to the result of analysis on soil erosion hazard zone of farm land by classifying it into 5 classes, the Class V has the highest soil erosion hazard, approximately 72.5ha that corresponds to 2.4% of the total farm land was estimated as an erosion hazard zone. This erosion hazard shows 72.4ha in dry field crop planting area, 0.1ha in an orchard, but the highest hazard zone, the Class V was not shown in other farming areas. Also, it showed that Class II area had the most ratio of the entire farm land, i.e., 70.2%, regardless of land use state.

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Analysis of Relationship between Land Cover Change and Vegetation Temperature Condition Index in Central Dry Zone of Myanmar (미얀마 건조지 토지피복 변화와 식생온도조건지수간의 관계분석)

  • Choi, Sol-E;Lee, Woo-Kyun;Yu, Hangnan;Kang, Ho-Duck;Kim, Yong-Suk
    • Journal of the Korean Association of Geographic Information Studies
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    • v.17 no.2
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    • pp.82-94
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    • 2014
  • The purpose of this study is to investigate the cause of increasing dry zones through analyzing relationships between land cover and Vegetation Temperature Condition Index(VTCI) using Landsat 4-5 TM satellite images in Central Dry Zones of Myanmar. As a result of land cover classifications, while vegetation areas gradually decrease, residential area and cropland were increased. VTCI analysis shows that region (a) showed a gradual decrease in the area of severely arid, and increase in the area of moderate dry and wet, which sums up to a slight decrease in aridity. Region (b) also showed to increase in dry areas and severe aridity. The result of relational analysis between VTCI and land cover change showed high ratio of land cover change, from severe arid area to forest and residential farmland. The average VTCI decreased in the changed land covers, which indicates the relationship between aridity and land cover change and a gradual increase in the arid area was identified.

Analysis of Payload Technical Specifications for Efficient Agriculture and Forestry Satellite Observation (효율적인 농림업 위성관측을 위한 탑재체 기술사양 분석)

  • Kim, Bum-Seung;Lee, Kyung-Do;Hong, Suk-Young;Lee, Woo-Kyung
    • Korean Journal of Remote Sensing
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    • v.32 no.3
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    • pp.287-305
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    • 2016
  • Over the past half century, satellites have continuously expanded their roles in remote sensing applications. As the number of satellites to be launched are expected to continuously increase in coming years, the research on satellite payloads will be in high demands. Earth Observation (EO) satellites are nowadays widely utilized for various purposes. Especially, Agriculture and forestry applications are considered as their major application areas. Since about 85% of domestic land cover is classified as forest or cropland areas, it would be reasonable to suggest that the demand for these satellites should be of high priority. In this paper, a comprehensive analysis is performed on the technical specifications of satellite payloads that may be applicable to agricultural applications. We attempted to build a solid database on payload specifications by collecting relevant information available from various related institutes and academic research works. A number of experts involved in national agricultural research and satellite development programs have been invited to investigate required payload design. Based on the current technology development status and future plan, multiple options for future satellite payload designs have been suggested bearing in mind that the results may be applicable to the future agriculture and forestry satellite payload design. The proposed payload specifications are analyzed in depth through satellite operation simulations under the mission of observing the national agriculture areas. The proposed design scheme and simulation results may be used as technical references to satellite payload design for future space missions.

A Study on the Soil Erosion by Landuse in the Imjin River Basin, DMZ of Cental Korea (임진강유역의 토지이용에 따른 지표침식에 관한 연구)

  • Lee, Min-Boo;Kim, Nam-Shin;Jin, Shizhu;Kim, Hang-Deok
    • Journal of the Korean Geographical Society
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    • v.43 no.3
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    • pp.263-275
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    • 2008
  • This Study deals with the comparative analysis on the estimation of surface soil erosion volume between South and North Korea using RUSLE model in Imjin River basin located on DMZ of Central Korea. Comparatively North Korea areas have been more eroded three times as much as South Korea parts. Because of cropland development such as com Held in the hillslope, in North Korea, more surface soil erosion and transportation to the river bed has given rise to frequent flood hazards. It seems that the study can dedicate to mitigation of environmental problems such as soil erosion and flooding in unaccessible Imjin River basin located on DMZ.

Kansas Vegetation Mapping Using Multi-Temporal Remote Sensing Data: A Hybrid Approach (계절별 위성자료를 이용한 미국 캔자스주 식생 분류 - 하이브리드 접근방식의 적용 -)

  • ;Stephen Egbert;Dana Peterson;Aimee Stewart;Chris Lauver;Kevin Price;Clayton Blodgett;Jack Cully, Jr,;Glennis Kaufman
    • Journal of the Korean Geographical Society
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    • v.38 no.5
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    • pp.667-685
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    • 2003
  • To address the requirements of gap analysis for species protection, as well as the needs of state and federal agencies for detailed digital land cover, a 43-class map at the vegetation alliance level was created for the state of Kansas using multi-temporal Thematic Mapper imagery. The mapping approach included the use of three-date multi-seasonal imagery, a two-stage classification approach that first masked out cropland areas using unsupervised classification and then mapped natural vegetation with supervised classification, visualization techniques utilizing a map of small multiples and field experts, and extensive use of ancillary data in post-hoc processing. Accuracy assessment was conducted at three levels of generalization (Anderson Level I, vegetation formation, and vegetation alliance) and three cross-tabulation approaches. Overall accuracy ranged from 51.7% to 89.4%, depending on level of generalization, while accuracy figures for individual alliance classes varied by area covered and level of sampling.