• Title/Summary/Keyword: Land covers

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Analyzing the Spatial Change of Urban Green Spaces with Cell Based Spatial Metrics : A Case Study of Daegu (화소 기반 공간메트릭스를 이용한 도시 녹지의 공간적 변화 분석: 대구시를 사례로)

  • Seo, Hyun-Jin;Jun, Byong-Woon
    • Journal of the Korean association of regional geographers
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    • v.23 no.1
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    • pp.136-150
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    • 2017
  • This study analyzed the spatial change of urban green spaces in Daegu from 1989 to 2009 using cell based spatial metrics. To do so, the conversion process of land covers during the past 20 years was explored using a land cover change detection matrix. The synoptic analysis with a moving window sampling strategy was conducted to quantify cell based spatial metrics related to size, shape, cohesion, and diversity and to explain the spatial change at the local level. Difference maps were then generated by subtracting the 1989 maps of spatial metrics from the 1998 maps and the 1998 maps from the 2009 maps. The gradient analysis was performed to identify the directional change of spatial metrics along an urban development axis in Daegu. The results from this study show that urban green spaces in Daegu during the past 20 years have been gradually fragmented around the new town housing development districts such as Dalseong-gun, Seongseo, and Ansim. Forests were most prominently fragmented in the Hwawon area while most rapidly in the Chilgok area. Grasslands were largely fragmented in many areas due to the decrease in size and cohesion indices and most fragmented in the Ansim area. The spatial pattern of the decreased and fragmented urban green spaces identified by this study can be used as a base data for establishing the environment-friendly urban development strategy in Daegu.

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A study on old trees as they relate to the organization of space in Pusan -Attaching importance to the growth environment and arrangement form in space- (부산시 노거수의 공간구성에 관한 연구 -생육환경 및 배치형태를 중심으로-)

  • 김승환;김순희
    • Journal of the Korean Institute of Landscape Architecture
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    • v.24 no.2
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    • pp.86-98
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    • 1996
  • This study is intended to revaluate old tree, five of the shot of the Natural Monument and 66 shot trees under protection in the city at present. The study covers distribution, management of usage, investigation and research into various matters relating to the situation of old trees in Pusan. Because 60% of the old trees selected for protection is on private land, citizens have difficulty gaining access to them. Also space for growth is impinged on by various urban facilities. Some trees have problems of growth because the land is covered with cement and asphalt. As regards space for old trees, many places have been destroyed due to the lack of protection fences and the failure to establish a guidance board. Only 40% of the space has been set aside for rest. In these places the establishment of rest areas, benches and handy chairs is needed. And there are 20 holy places where people observe religious ceremonies. As for space security necessary for old trees according to trunk width, the minimum trunk width and availale area needed are more than 1:1.5, but less than 30% have the necessary space. The growth of many old trees is threatended because of the small apace for growth. The prescription of the boundary space is divided between inside and outside. This indicates the domain nature and space rank of the old tree. It can be classified into five forms for research purposes. The elements for prescription of critical space outside are connected with the security of space, and the elements relating to inside space portray the conditions for sensitive growth according to the institution and the ground conditions. The open and closed nature of old tree space has some connection with the relationship between usage and the intimacy of the user. Most of the spaces for old trees can't be used or are difficult to gain access to, so it is necessary to secure enough space for them. The 18 places, despite having easy access, are near farmland, hills or forest. So the intimacy factor is low, and the security of space of the old trees is not generally sufficient. Henceforth, it will be necessary to have security of area for old trees as well as maintenance control to protect them. Also the space should be used as a communal and recreation are in the city. It is the time to construct a landscaped area which people can easily approach, a place with a secure entrance where they can play, rest and converse.

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Factors Affecting Household Water Use during the COVID-19 Period: A Focus on the 33 Autonomous Districts of Seoul and Incheon (COVID-19 시기 가정용 상수도 사용에 영향을 미치는 요인에 관한 연구: 서울과 인천의 자치구 33개를 대상으로)

  • Song, Yiseul;Jo, Hanghun;Kim, Heungsoon
    • Land and Housing Review
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    • v.13 no.4
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    • pp.1-12
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    • 2022
  • Clean water is an essential urban infrastructure in human daily life, and water plays a vital role in public health. Due to restrictions on outdoor activities during COVID-19, time staying at home has increased. Therefore, it is plausible to assume that large-scale disaster incidences such as COVID-19 will affect water consumption. In this regard, this research aims to explore the factors that influence household water use during COVID-19. The analysis period of the study is 2020, and the geographical scope covers Seoul and Incheon. A dependent variable was water consumption in the autonomous districts of Seoul and Incheon, and the factors reflecting urban characteristics were used as independent variables. Multiple regression was used for analysis, and the unit of analysis was the autonomous district in Seoul and Incheon. The finding confirmed that the pandemic situation caused an increase in water consumption. In addition, it supports policy for the elderly so that they can use water without financial difficulty. It implies that a stable supply of clean water is essential for managing infectious diseases. The findings of this study are expected to provide some implications for efficient water supply policies and efficient water supply management in the event of the spread of infectious diseases such as COVID-19.

A Comparison of Pixel- and Segment-based Classification for Tree Species Classification using QuickBird Imagery (QuickBird 위성영상을 이용한 수종분류에서 픽셀과 분할기반 분류방법의 정확도 비교)

  • Chung, Sang Young;Yim, Jong Su;Shin, Man Yong
    • Journal of Korean Society of Forest Science
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    • v.100 no.4
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    • pp.540-547
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    • 2011
  • This study was conducted to compare classification accuracy by tree species using QuickBird imagery for pixel- and segment-based classifications that have been mostly applied to classify land covers. A total of 398 points was used as training and reference data. Based on this points, the points were classified into fourteen land cover classes: four coniferous and seven deciduous tree species in forest classes, and three non-forested classes. In pixel-based classification, three images obtained by using raw spectral values, three tasseled indices, and three components from principal component analysis were produced. For the both classification processes, the maximum likelihood method was applied. In the pixel-based classification, it was resulted that the classification accuracy with raw spectral values was better than those by the other band combinations. As resulted that, the segment-based classification with a scale factor of 50% provided the most accurate classification (overall accuracy:76% and ${\hat{k}}$ value:0.74) compared to the other scale factors and pixel-based classification.

Analysis of Eco-Area Application Characteristics of Apartment Complexes : Focusing on Eco-Area Ratio, Eco-Area Diversity, and Eco-Area Connectivity (공동주택단지 생태면적 적용 특성 분석 : 생태면적률, 생태면적 다양성, 생태면적 연계성을 중심으로)

  • Seung-Bin An;Chan-Ho Kim;Chang-Soo Lee
    • Land and Housing Review
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    • v.15 no.1
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    • pp.77-97
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    • 2024
  • This study aims to examine the distinctions in evaluation index items between overseas and domestic ecological area-related systems, derive analytical indicators, and assess recently completed apartment complexes before and after the implementation of overall ecological area ratios. The objective is to analyse variances in the application of ecological area characteristics, categorizing them into ecological area analysis indicators and presenting their implications. The spatial scope covers completed apartment complexes in both metropolitan and non-metropolitan areas. Thirty-six completed apartment complexes were selected for analysis, and basic ecological area data were compiled. Subsequently, the data was utilized to categorize three analysis indicators-ecological area ratio, ecological area diversity, and ecological area connectivity-by metropolitan and non-metropolitan areas, as well as by type of apartment complex (sale housing versus rental housing) and size (large-scale, medium-scale, and small-scale). Results of the analysis indicate higher ecological area ratios and greater diversity in ecological area spatial types in metropolitan areas compared to non-metropolitan areas, and in pre-sale housing complexes compared to rental housing complexes. Mediumand large-scale apartment complexes exhibit higher ecological area ratios, with ecological area diversity being more pronounced. Ecological area connectivity reveals more numerous and varied connection points and types in metropolitan areas than in non-metropolitan areas. Implications of this study suggest that large-scale development should prioritize securing ecological area ratios and diversity in apartment complexes. Enhancing biodiversity necessitates establishing connections within and beyond the ecological area network of the complex. Future research should focus on linking the ecological area network within the complex.

Estimation of Fractional Urban Tree Canopy Cover through Machine Learning Using Optical Satellite Images (기계학습을 이용한 광학 위성 영상 기반의 도시 내 수목 피복률 추정)

  • Sejeong Bae ;Bokyung Son ;Taejun Sung ;Yeonsu Lee ;Jungho Im ;Yoojin Kang
    • Korean Journal of Remote Sensing
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    • v.39 no.5_3
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    • pp.1009-1029
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    • 2023
  • Urban trees play a vital role in urban ecosystems,significantly reducing impervious surfaces and impacting carbon cycling within the city. Although previous research has demonstrated the efficacy of employing artificial intelligence in conjunction with airborne light detection and ranging (LiDAR) data to generate urban tree information, the availability and cost constraints associated with LiDAR data pose limitations. Consequently, this study employed freely accessible, high-resolution multispectral satellite imagery (i.e., Sentinel-2 data) to estimate fractional tree canopy cover (FTC) within the urban confines of Suwon, South Korea, employing machine learning techniques. This study leveraged a median composite image derived from a time series of Sentinel-2 images. In order to account for the diverse land cover found in urban areas, the model incorporated three types of input variables: average (mean) and standard deviation (std) values within a 30-meter grid from 10 m resolution of optical indices from Sentinel-2, and fractional coverage for distinct land cover classes within 30 m grids from the existing level 3 land cover map. Four schemes with different combinations of input variables were compared. Notably, when all three factors (i.e., mean, std, and fractional cover) were used to consider the variation of landcover in urban areas(Scheme 4, S4), the machine learning model exhibited improved performance compared to using only the mean of optical indices (Scheme 1). Of the various models proposed, the random forest (RF) model with S4 demonstrated the most remarkable performance, achieving R2 of 0.8196, and mean absolute error (MAE) of 0.0749, and a root mean squared error (RMSE) of 0.1022. The std variable exhibited the highest impact on model outputs within the heterogeneous land covers based on the variable importance analysis. This trained RF model with S4 was then applied to the entire Suwon region, consistently delivering robust results with an R2 of 0.8702, MAE of 0.0873, and RMSE of 0.1335. The FTC estimation method developed in this study is expected to offer advantages for application in various regions, providing fundamental data for a better understanding of carbon dynamics in urban ecosystems in the future.

Zooplankton Community Distribution and Food Web Structure in Small Reservoirs: Influence of Land Uses around Reservoirs and Kittoral Aquatic Plant on Zooplankton (소형저수지에서 동물플랑크톤 군집 분포와 먹이망 구조: 주변 토지 이용과 수변식생이 동물플랑크톤 군집에 미치는 영향)

  • Choi, Jong-Yun;Kim, Seong-Ki;Hong, Sung-Won;Jeong, Kwang-Seuk;La, Geung-Hwan;Joo, Gea-Jae
    • Korean Journal of Ecology and Environment
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    • v.46 no.3
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    • pp.332-342
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    • 2013
  • We collected zooplankton from May to October, 2011, with the aim of understanding the zooplankton community distribution and food web interaction between the open water and littoral (aquatic plants) zones in two small reservoirs with different land covers (Sobudang, Myeongdong). Small-sized reservoirs are more abundant in South Korea, and a total of 51 and 65 species of zooplankton were identified at the two small reservoir (Sobudang and Myeongdong), where zooplankton densities were more abundant in the littoral zone than in the open water zone. Cladocerans and copepods densities were also higher in the littoral zone, in contrast, rotifers showed higher densities in the open water zone (t-test, P/0.05). Epiphytic zooplankton dominated at the littoral zone (Lecane, Monostyla, Alona and Chydorus) because aquatic plants provided refuge spaces for attachment. Some rotifers (e.g. Brachionus, Keratella and Polyarthra) were more abundant in the open water zone because of their small size, which might help them to go unnoticed by predators. In two-way ANOVA, rotifers related to two reservoirs or habitat space (littoral zone and open water zone), but cladocerans and copepods showed a statistically significant relationship on only two reservoirs. The results of stable isotope analysis showed that zooplankton in the littoral zone tended to depend on organic matter attached to aquatic plants as a food source, which indicates the avoidance of competition of zooplankton with other macro-invertebrates (e.g. Damselfly larva, Cybister brevis and Neocardina denticulate). As a result, zooplankton community distribution is determined by not only habitat space (aquatic plant zone and open water zone) but also by food source (phytoplankton).

The NCAM Land-Atmosphere Modeling Package (LAMP) Version 1: Implementation and Evaluation (국가농림기상센터 지면대기모델링패키지(NCAM-LAMP) 버전 1: 구축 및 평가)

  • Lee, Seung-Jae;Song, Jiae;Kim, Yu-Jung
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.18 no.4
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    • pp.307-319
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    • 2016
  • A Land-Atmosphere Modeling Package (LAMP) for supporting agricultural and forest management was developed at the National Center for AgroMeteorology (NCAM). The package is comprised of two components; one is the Weather Research and Forecasting modeling system (WRF) coupled with Noah-Multiparameterization options (Noah-MP) Land Surface Model (LSM) and the other is an offline one-dimensional LSM. The objective of this paper is to briefly describe the two components of the NCAM-LAMP and to evaluate their initial performance. The coupled WRF/Noah-MP system is configured with a parent domain over East Asia and three nested domains with a finest horizontal grid size of 810 m. The innermost domain covers two Gwangneung deciduous and coniferous KoFlux sites (GDK and GCK). The model is integrated for about 8 days with the initial and boundary conditions taken from the National Centers for Environmental Prediction (NCEP) Final Analysis (FNL) data. The verification variables are 2-m air temperature, 10-m wind, 2-m humidity, and surface precipitation for the WRF/Noah-MP coupled system. Skill scores are calculated for each domain and two dynamic vegetation options using the difference between the observed data from the Korea Meteorological Administration (KMA) and the simulated data from the WRF/Noah-MP coupled system. The accuracy of precipitation simulation is examined using a contingency table that is made up of the Probability of Detection (POD) and the Equitable Threat Score (ETS). The standalone LSM simulation is conducted for one year with the original settings and is compared with the KoFlux site observation for net radiation, sensible heat flux, latent heat flux, and soil moisture variables. According to results, the innermost domain (810 m resolution) among all domains showed the minimum root mean square error for 2-m air temperature, 10-m wind, and 2-m humidity. Turning on the dynamic vegetation had a tendency of reducing 10-m wind simulation errors in all domains. The first nested domain (7,290 m resolution) showed the highest precipitation score, but showed little advantage compared with using the dynamic vegetation. On the other hand, the offline one-dimensional Noah-MP LSM simulation captured the site observed pattern and magnitude of radiative fluxes and soil moisture, and it left room for further improvement through supplementing the model input of leaf area index and finding a proper combination of model physics.

Effects of Gypsum on Dry Matter Yield and Chemical Composition of Alfalfa in Reclaimed Tidal Land with Soil Dressing (객토 간척지에서 석고처리가 알팔파 건물수량 및 사료성분에 미치는 영향)

  • Kim, Ji Yung;Jo, Hyun Wook;Lee, Bae Hun;Jo, Mu Hwan;Kim, Byong Wan;Sung, Kyung Il
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.41 no.4
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    • pp.223-233
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    • 2021
  • The objective of this study was to investigate the effect of gypsum on the dry matter yield and the chemical composition of alfalfa in reclaimed tideland with soil dressing. The experimental site was Sukmoon reclaimed tideland. The tideland was reclaimed approximately 17 to 33 years ago and the 70 cm of soil was top-dressed. The soil that covers the reclaimed tideland brought from the island did not treat di-salinized. Treatments were consisted of three groups; control group where no gypsum (G0) was applied and two experimental groups where 2 ton/ha (G2) and 4 ton/ha (G4) of gypsum were applied, respectively. The first harvest was conducted when the alfalfa reached early flowering (open the flower 10%), and after that subsequent harvest was conducted at approximately 35 days intervals. The dry matter yield of the alfalfa showed that G2 was significantly higher in the first year than G0 and G4, and G2 tended to be higher in the second year than G0 and G4, although there were no significant differences between treatments. The reason for the high dry matter yield in G2 was that the soil pH and EC of the soil were at marginal and ideal levels and the coverage and alfalfa botanical composition were also high. In both years, there were no differences in the crude protein, neutral detergent fiber and acid detergent fiber contents and relative feed value between gypsum treatments. Meanwhile, the results in the first and second years showed that the alfalfa dry matter yield were negatively affected by droughts stress in spring and concentrated precipitation in summer. Therefore, this study suggests gypsum treatment in reclaimed tidal land could increase the dry matter yield of alfalfa, and 2 ton/ha of gypsum was the optimum rate.

A basic study on the creation of historic revolutionary sites in North Korea (북한의 혁명사적지 및 혁명전적지 형성에 관한 기초연구)

  • 김동찬;안봉원;서주환;김광래;김신원
    • Journal of the Korean Institute of Landscape Architecture
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    • v.23 no.4
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    • pp.61-80
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    • 1996
  • This research study presents historic revolutionary sites in North Korea. In this study, the creation of historic revolutionary sites in North Korea after the Liberation of Korea in 1945, as yet unpublished in the field of landscape architecture and urban planning, is investigated. For conducting this study, the method of true and urban planning, is investigated. For conducting this study, the method of archival research, in which regarding documents, plans and photographs are investigated, was used. This study covers notions, establishment, related laws and regulations, distribution and present status, developmental stages, concrete examples, and general characteristics, of historic revolutionary sites in North Korea. In North Korea, historic revolutionary sites mean all the places where revolutionary achievements of Kim, Ill-Sung and his family are reached. Those sites have been actively created for the purpose of the idolization of Kim, Ill-Sung since the 1960s. In recent years, the sites have been revobated and new places of this kind have been constructed, so that various idolization facilities and structures are now everywhere in North Korea. Historic revolutionary sites are mainly distributed now everywhere in North Korea. Historic revolutionary sites are mainly distributed now everywhere in North Korea. Historic revolutionary sites are mainly distributed in Pyungyang, the forest areas of Mt. Pakdu, the areas along the shore of the Tuman River and the Abrock River. In those sites, various historic revolutionary relics are preserved, and the statues of Kim, Ill-Sung, historic revolutionary monuments, revolutionary museums and other facilities are constructed. These places can not be regarded as planned spaces for people in true the meaning of place, and accordingly they must be reconstructed for people's use. They can be redeveloped as places of history, culture and deucation, theme parks, green open spaces, and sight-seeing facilities after unification of Korea. This study can be used as valuable information for further study especially for the reconstruction planning of the places in preparation for a probable unified Korea. For a profound study, North Korea must open broader and more accurately detailed documents, regarding historic revolutionary sites, to the outside world, and the South Korean Government must also have a sense of co-ownership of the information about North Korea rather than exclusive possession and restrictions. Ultimately, academic exchange between South and North Korea must be realized and on-the-spot surveys must be carried out so as to find a reasonable land use plan for the historic revolutionary sites for a future unified Korea.

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