• Title/Summary/Keyword: forest statistics

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Analysis of Utilization and Perception of Special Weather Reports for Climate Change Adaptation: Focus on Dryness Advisory and Warning (기후변화적응을 위한 기상특보 인지도 및 활용도 분석: 건조특보를 중심으로)

  • Choi, Su-Jin;Kim, Eun-Byul;Jung, Woo-Sik;Kim, Baek-Jo;Park, Jong-Kil
    • Journal of Environmental Science International
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    • v.23 no.6
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    • pp.1121-1130
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    • 2014
  • This study aims to find the perception and utilization of the citizen about the dryness watch warning (DWW) among special weather reports. For this we have made up a descriptive questionnaire including the perception, utilization of special weather reports. Using the SPSS 17.0 program, descriptive statistics, t-test, ANOVA and Scheffe test were used to analyze the collected data. The results are as follows; The perception of DWW is measured by 4 point Likert scale and the average is $15.97{\pm}3.70$ (percentile=57.0). This value shows that the awareness level is not that high and according to the occupation, college students show the lowest awareness and housewives show the highest awareness. According to the age, the teens and twenties show the lowest awareness and fifties and sixties show the highest awareness. Although the perception of the teens and college students are rather poor, there were many positive answers that it is necessary to establish the advanced disaster prevention plan according to the questionnaire about the utilization of DWW. Therefore, if we come up with an effective plan to improve the perception than we can expect a large-effect in terms of fire and forest fire prevention. The perception of DWW can be improved by providing weather information and weather related education program on TV or internet which have the high level of preference. Also, it is necessary to provide online and offline program of advertising education and disaster management education through the weather forecast bureau which is the host organization of delivering weather information.

Development of Landslide Hazard Map Using Environmental Information System: Case on the Gyeongsangbuk-do Province (환경정보시스템을 이용한 산사태 발생위험 예측도 작성: 경상북도를 중심으로)

  • Bae, Min-Ki;Jung, Kyu-Won;Park, Sang-Jun
    • Journal of Environmental Science International
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    • v.18 no.11
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    • pp.1189-1197
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    • 2009
  • The purpose of this research was develop tailored landslide hazard assessment table (LHAT) in Gyeongsangbuk-do Province and propose building strategies on environmental information system to estimate landslide hazard area according to LHAT. To accomplish this purpose, this research investigated factors occurring landslide at 172 landslide occurred sites in 23 city and county of Gyeongsangbuk-do Province and analyzed what factors effected landslide occurrence quantity using the multiple statistics of quantification method(I). The results of analysis, factors affecting landslide occurrence quantity were shown in order of slope position, slope length, bedrock, aspect, forest age, slope form and slope. And results of the development of LHAT for predict mapping of landslide-susceptible area in Gyeongsangbuk-do Province, total score range was divided that 107 under is stable area(IV class), 107~176 is area with little susceptibility to landslide(III class), 177~246 is area with moderate susceptibility to landslide(II class), above 247 area with severe susceptibility to landslide(I class). According to LHAT, this research built landslide attribute database and made 7 digital theme maps at mountainous area located in Goryeong Gun, Seongju-Gun, and Kimcheon-City. The results of prediction on degree of landslide hazard using environmental information system, area with little susceptibility to landslide(III class) occupied 65.56% and severe susceptibility to landslide(I class) occupied 0.51%.

Development of a Web-based Geovisualization System using Google Earth and Spatial DBMS (구글어스와 공간데이터베이스를 이용한 웹기반 지리정보 표출시스템 개발)

  • Im, Woo-Hyuk;Lee, Yang-Won;Suh, Yong-Cheol
    • Spatial Information Research
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    • v.18 no.4
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    • pp.141-149
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    • 2010
  • One of recent trends in Web-based GIS is the system development using FOSS (Free and Open Source Software). Open Source software is independent from the technologies of commercial software and can increase the reusability and extensibility of existing systems. In this study, we developed a Web-based GIS for interactive visualization of geographic information using Google Earth and spatial DBMS(database management system). Google Earth Plug-in and Google Earth API(application programming interface) were used to embed a geo-browser in the Web browser. In order to integrate the Google Earth with a spatial DBMS, we implemented a KML(Keyhole Markup Language) generator for transmitting server-side data according to user's query and converting the data to a variety of KML for geovisualization on the Web. Our prototype system was tested using time-series of LAI(leaf area index), forest map, and crop yield statistics. The demonstration included the geovisualization of raster and vector data in the form of an animated map and a 3-D choropleth map. We anticipate our KML generator and system framework will be extended to a more comprehensive geospatial analysis system on the Web.

Recent Spatio-temporal Changes of Landscape Structure, Heterogeneity and Diversity of Rural Landscape: Implements for Landscape Conservation and Restoration (한국 농산촌 경관의 구조와 이질성 및 다양성의 최근 변화: 경관의 보전과 복원과의 관계)

  • Hong, Sun-Kee;Rim, Young-Deuk;Nakagoshi, Nobukazu;Chang, Nam-Kee
    • The Korean Journal of Ecology
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    • v.23 no.5
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    • pp.359-368
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    • 2000
  • Landscape change is the modification and replacement of landscape elements in accordance with human management and natural disturbance on land mosaics. During landscape change, changes in patterns such as heterogeneity, diversity and shape, and juxtaposition of spatial elements are also accompanied. For the sustainable landscape system, therefore, spatial characteristics of the landscape should be considered in implementation of landscape conservation and restoration planning. Short-term changes of land-use and landscape pattern during the 10 years of 1980s and 1990s were investigated in the agriculture-forestry dominated landscape system through the statistics and the analysis of landscape-vegetation map. Study area is Yangdong-myon, Yangpyung-gun (37°27′30"N, 127°46′50"E), Kyonggi-do, in central Korea. Landscape change of this region was significantly related to the recent industrialization according to socio-economic development. Analyses of landscape pattern show that the area of secondary forest sustained by human activity decreased and it was replaced with large exotic plantations during this period. Area of paddy field was also extended. Fractal dimension of the total landscape increased, but that of paddy field area decreased due to rearrangement for mechanized farming. Moreover, the area of landscape management regimes such as plantation and cultivation increased in land mosaics during this period.

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Testing Non-Stationary Relationship between the Proportion of Green Areas in Watersheds and Water Quality using Geographically Weighted Regression Model (공간지리 가중회귀모형(GWR)을 이용한 유역 녹지비율과 하천수질의 비균질적 관계 검증)

  • Lee, Sang-Woo
    • Journal of the Korean Institute of Landscape Architecture
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    • v.41 no.6
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    • pp.43-51
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    • 2013
  • This study aims to examine the presence of non-stationary relationship between water quality and land use in watersheds. In investigating the relationships between land use and water quality, most previous studies adopted OLS method which is assumed stationarity. However, this approach is difficult to capture the local variation of the relationships. We used 146 sampling data and land cover data of Korean Ministry of Environment to build conventional regressions and GWR models for BOD, TN and TP. Regression model and GWR models of BOD, TN, TP were compared with $R^2$, AICc and Moran's I. The results of comparisons and descriptive statistics of GWR models strongly indicated the presence of Non-Stationarity between water quality and land use.

Prediction of Daily PM10 Concentration for Air Korea Stations Using Artificial Intelligence with LDAPS Weather Data, MODIS AOD, and Chinese Air Quality Data

  • Jeong, Yemin;Youn, Youjeong;Cho, Subin;Kim, Seoyeon;Huh, Morang;Lee, Yangwon
    • Korean Journal of Remote Sensing
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    • v.36 no.4
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    • pp.573-586
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    • 2020
  • PM (particulate matter) is of interest to everyone because it can have adverse effects on human health by the infiltration from respiratory to internal organs. To date, many studies have made efforts for the prediction of PM10 and PM2.5 concentrations. Unlike previous studies, we conducted the prediction of tomorrow's PM10 concentration for the Air Korea stations using Chinese PM10 data in addition to the satellite AOD and weather variables. We constructed 230,639 matchups from the raw data over 3 million and built an RF (random forest) model from the matchups to cope with the complexity and nonlinearity. The validation statistics from the blind test showed excellent accuracy with the RMSE (root mean square error) of 9.905 ㎍/㎥ and the CC (correlation coefficient) of 0.918. Moreover, our prediction model showed a stable performance without the dependency on seasons or the degree of PM10 concentration. However, part of coastal areas had a relatively low accuracy, which implies that a dedicated model for coastal areas will be necessary. Additional input variables such as wind direction, precipitation, and air stability should also be incorporated into the prediction model as future work.

The long-term agricultural weather forcast methods using machine learning and GloSea5 : on the cultivation zone of Chinese cabbage. (기계학습과 GloSea5를 이용한 장기 농업기상 예측 : 고랭지배추 재배 지역을 중심으로)

  • Kim, Junseok;Yang, Miyeon;Yoon, Sanghoo
    • Journal of Digital Convergence
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    • v.18 no.4
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    • pp.243-250
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    • 2020
  • Systematic farming can be planned and managed if long-term agricultural weather information of the plantation is available. Because the greatest risk factor for crop cultivation is the weather. In this study, a method for long-term predicting of agricultural weather using the GloSea5 and machine learning is presented for the cultivation of Chinese cabbage. The GloSea5 is a long-term weather forecast that is available up to 240 days. The deep neural networks and the spatial randomforest were considered as the method of machine learning. The longterm prediction performance of the deep neural networks was slightly better than the spatial randomforest in the sense of root mean squared error and mean absolute error. However, the spatial randomforest has the advantage of predicting temperatures with a global model, which reduces the computation time.

Potential Impact of Climate Change on Distribution of Hedera rhombea in the Korean Peninsula (기후변화에 따른 송악의 잠재서식지 분포 변화 예측)

  • Park, Seon Uk;Koo, Kyung Ah;Seo, Changwan;Kong, Woo-Seok
    • Journal of Climate Change Research
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    • v.7 no.3
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    • pp.325-334
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    • 2016
  • We projected the distribution of Hedera rhombea, an evergreen broad-leaved climbing plant, under current climate conditions and predicted its future distributions under global warming. Inaddition, weexplained model uncertainty by employing 9 single Species Distribution model (SDM)s to model the distribution of Hedera rhombea. 9 single SDMs were constructed with 736 presence/absence data and 3 temperature and 3 precipitation data. Uncertainty of each SDM was assessed with TSS (Ture Skill Statistics) and AUC (the Area under the curve) value of ROC (receiver operating characteristic) analyses. To reduce model uncertainty, we combined 9 single SDMs weighted by TSS and resulted in an ensemble forecast, a TSS weighted ensemble. We predicted future distributions of Hedera rhombea under future climate conditions for the period of 2050 (2040~2060), which were estimated with HadGEM2-AO. RF (Random Forest), GBM (Generalized Boosted Model) and TSS weighted ensemble model showed higher prediction accuracies (AUC > 0.95, TSS > 0.80) than other SDMs. Based on the projections of TSS weighted ensemble, potential habitats under current climate conditions showed a discrepancy with actual habitats, especially in the northern distribution limit. The observed northern boundary of Hedera rhombea is Ulsan in the eastern Korean Peninsula, but the projected limit was eastern coast of Gangwon province. Geomorphological conditions and the dispersal limitations mediated by birds, the lack of bird habitats at eastern coast of Gangwon Province, account for such discrepancy. In general, potential habitats of Hedera rhombea expanded under future climate conditions, but the extent of expansions depend on RCP scenarios. Potential Habitat of Hedera rhombea expanded into Jeolla-inland area under RCP 4.5, and into Chungnam and Wonsan under RCP 8.5. Our results would be fundamental information for understanding the potential effects of climate change on the distribution of Hedera rhombea.

Feature Extraction and Fusion for land-Cover Discrimination with Multi-Temporal SAR Data (다중 시기 SAR 자료를 이용한 토지 피복 구분을 위한 특징 추출과 융합)

  • Park No-Wook;Lee Hoonyol;Chi Kwang-Hoon
    • Korean Journal of Remote Sensing
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    • v.21 no.2
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    • pp.145-162
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    • 2005
  • To improve the accuracy of land-cover discrimination in SAB data classification, this paper presents a methodology that includes feature extraction and fusion steps with multi-temporal SAR data. Three features including average backscattering coefficient, temporal variability and coherence are extracted from multi-temporal SAR data by considering the temporal behaviors of backscattering characteristics of SAR sensors. Dempster-Shafer theory of evidence(D-S theory) and fuzzy logic are applied to effectively integrate those features. Especially, a feature-driven heuristic approach to mass function assignment in D-S theory is applied and various fuzzy combination operators are tested in fuzzy logic fusion. As experimental results on a multi-temporal Radarsat-1 data set, the features considered in this paper could provide complementary information and thus effectively discriminated water, paddy and urban areas. However, it was difficult to discriminate forest and dry fields. From an information fusion methodological point of view, the D-S theory and fuzzy combination operators except the fuzzy Max and Algebraic Sum operators showed similar land-cover accuracy statistics.

Analyzing Climate Zones Using Hydro-Meteorological Observation Data in Andong Dam Watershed, South Korea (수문기상 관측정보를 활용한 안동댐 유역 기후권역 구분 및 분석)

  • Kim, Sea Jin;Lim, Chul-Hee;Lim, Yoon-Jin;Moon, Jooyeon;Song, Cholho;Lee, Woo-Kyun
    • Journal of Climate Change Research
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    • v.7 no.3
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    • pp.269-282
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    • 2016
  • Watershed area can be submerged due to constructions and management of dams, and these change can impact not only on ecosystem and environment of river basin area but also on local climate. This study is conducted to construct and classify climate zones of Andong Dam watershed where the area is submerged due to the construction of the dam. By applying Principal Components Analysis (PCA) and Getis-Ord $Gi^*$ statistics, three climate zones were classified for the result. Each zone was then analyzed and validated with climatic and geological features including topography, land cover, and forest type map. As a result of the analysis, there was a difference in temperature, elevation, precipitation and tree species distribution among the zones. Also, an analysis of land cover map showed that there were more agricultural land near Andong Reservoir. This study on the climatic classification is considered to be useful as the basis for decision-making or policy enforcement regarding ecosystem, environmental management or climate change response.