• Journal of Ecology and Environment
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• v.34 no.2
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• pp.149-156
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• 2011

Phenological variables derived from remote sensing are useful in determining the seasonal cycles of ecosystems in a changing climate. Satellite remote sensing imagery is useful for the spatial continuous monitoring of vegetation phenology across broad regions; however, its applications are substantially constrained by atmospheric disturbances such as clouds, dusts, and aerosols. By way of contrast, a tower-based ground remote sensing approach at the canopy level can provide continuous information on canopy phenology at finer spatial and temporal scales, regardless of atmospheric conditions. In this study, a tower-based ground remote sensing system, called the "Phenological Eyes Network (PEN)", which was installed at the Gwangneung Deciduous KoFlux (GDK) flux tower site in Korea was introduced, and daily phenological progressions at the canopy level were assessed using ratios of red, green, and blue (RGB) spectral reflectances obtained by the PEN system. The PEN system at the GDK site consists of an automatic-capturing digital fisheye camera and a hemi-spherical spectroradiometer, and monitors stand canopy phenology on an hourly basis. RGB data analyses conducted between late March and early December in 2009 revealed that the 2G_RB (i.e., 2G - R - B) index was lower than the G/R (i.e., G divided by R) index during the off-growing season, owing to the effects of surface reflectance, including soil and snow effects. The results of comparisons between the daily PEN-obtained RGB ratios and daily moderate-resolution imaging spectroradiometer (MODIS)-driven vegetation indices demonstrate that ground remote sensing data, including the PEN data, can help to improve cloud-contaminated satellite remote sensing imagery.

• Journal of Korean Society of Rural Planning
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• v.22 no.4
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• pp.171-182
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• 2016

Since FAO introduced the Globally Important Agricultural Heritage Systems(GIAHS) in 2002, 36 sites of 15 countries so far have been listed on GIAHS. This study aims to find the important agricultural heritages of Korea and to prepare the methods for them to be selected as GIAHS. We have analyzed the proposals of the 36 GIAHS listed in order to study the characteristics of their components of the agricultural heritage which worked for being selected. To analyze the components of the agricultural heritage first, agricultural heritage was classified into 13 types and 42 components in light of GIAHS criteria. Then central themes were set to analyze the relevant contents in the proposals. They were, the type of GIAHS Site, significant agricultural landscape, the agriculture-forestry-fisheries-livestock linkage systems, the multi-layered, inter-cropping, circulation cultivation systems, the soil and water management systems, the conservation of agrobiological diversity and genetic resources, the history of the agricultural heritage, the succession of traditional farming techniques, the cultural diversity and so on. Most GIAHS are located in mountains, grasslands, rivers and coasts, desert than in plains, through which GIAHS assure us that it is the heritage of human challenge to overcome the harsh geographic environment and maintain a livelihood. In these sites the traditional farming techniques are carried on, such as mountain clearings, terraced rice paddies, and burn fields, and the unique irrigation systems and agricultural landscapes are well maintained, and the eco-friendly traditional farming techniques utilizing abundant forest resources and agriculture are well handed down. The origin or home of crop growing, a variety of genetic crop storage, the world's largest crop producer and preserving cultural diversity are also important factors for the selection.

• Korean Journal of Organic Agriculture
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• v.11 no.1
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• pp.79-88
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• 2003

Saved labor cost, energy conservation, reduced soil erosion, and increase of emergence rate would be expected from no-tillage cultivation of corn. Few research has been reported on the no-tillage effects for waxy corn hybrid. Five waxy com hybrids were tested under conventional and no-tillage practices to investigate responses of early growth, plant characters, ear characters, fresh yield, and grain yield. Emergence rates under no-tillage were lower than under conventional tillage. Plant heights at early growth stages under no-tillage were higher than those under conventional tillage. Plant height under no-tillage was higher than that under conventional tillage. There were no differences between conventional tillage and no-tillage for ear length, number of kernel rows, number of kernels per row, 100 kernels weight, fresh yield, and grain yield. This result indicates that no-tillage practice might be recommended for practical method for waxy com production. Days to tasseling and silking, plant height, ear height, ear length, and number of kernels per row were correlated with fresh and grain yields.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.9 no.6
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• pp.152-161
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• 2006

This study is the primary study for analyzing the classifying characteristics of river wetlands in Korea and China. It is the first step for constructing the wetlands inventories and establishing the wetland conservation strategies in North-Eastern Asia. The case study sites are Han-river which is the representative river of Korea and Tu-men river which is flowing on the borderline of 3 nations, China, North Korea and Russia. The results are as follows : 1. The types of wetlands of Han-river in Korea and Tumen-river in China were classified by the methods of Koo(2002) which is focused on the topography and hydrology and Zhu(2002) which is emphasized the vegetation and habitats. 2. There are three features which are hydrology, topography and soil cover, and vegetation to classify the wetlands into each types. 3. According to the two wetland types by Koo and Zhu, classification system, wetlands in the case study area(Han river and Duman river) were classified by types. 4. In Koo's classifying system(2002), lots of Riverine, Lacustrins and Flat wetlands are found because the topographical and hydrological features are emphasized. On the contrary in Zhu's system(2002), there are lots of Palustrine wetlands because of emphasizing the vegetation. 5. By the topographic and geological characteristics of each sites, there are more wetland types in the lower Tumen river.

• Journal of the Korean Society of Hazard Mitigation
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• v.7 no.4
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• pp.67-74
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• 2007

Rational method has been widely used to calculate peak runoff drainage design or small watershed because of simplicity and convenience. Runoff coefficient(C) is the most important parameter in the rational method which varies according to rainfall intensity, return period, rainfall duration time and soil characteristics. In practice, constant which is value of C in rational formula has been used from the table, originally based on ASCE. These table value does not consider the upper conditions of the depending factors, hence peak runoff calculation could be in correct. Therefore to calculate C in this paper we have devised an improved formula, considering relationship with rainfall duration, return period and CN of NRCS method. This formula is considered to be more reliable and helpful to the hydrologists and engineers to predict correct peak runoff.

• Proceedings of the Korea Contents Association Conference
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• 2007.11a
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• pp.937-941
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• 2007

For Hydrologic analysis of the river, the exact Dividing Watershed and Hydrologic-Topographical Parameters affect enormously Hydrologic analysis of the river basin. Therefore the extraction of Hydrologic-Topographical Parameters as well as Dividing Watershed are stiuied by several ways. However the definite standard of all those means are not settled. Recently GIS is applied to the field of water resources so that we can divide Watershed and calculate Hydrologic-Topographical Parameters of the targeted area easily and objective way for using DEM. Thanks to DEM, we don't have to spend much time as we did before. However other problems are generated such as the parameter value is changed by the precision of established NGIS(National Geographic Information System), etc. In this study, using GIS which is popular recently, we suggested efficient extract method of Hydrologic-Topographical Parameters SCS(Soil Conservation Service) CN(Curve Number) in watershed.

• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.668-670
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• 2004

Taipei Water Management Office (TWMO) is one of the eleven district offices in Water Resource Agency. Water management is the top priority to be pursued both on daily management and long-term management at TWMO. There are five departments to perform a wide range of tasks in addition to water management. All management prescriptions are simply to provide sustainable clean water for about four millions population in Taipei. TWMO has gone through 16 years experience of development and implementation of GIS in water management. The objectives of this paper are to provide the major ingredients of successful and operational GIS for water management. The five departments at TWMO have performed tasks such as city planning, construction management, forest management, land use enforcement, soil and water conservation, water quality monitoring and protection, garbage collection, and sewage disposal management. Data base creation was one of the major jobs to be done. Update of data base has to be done on a daily basis. Computers, its peripheral, and software are essential for GIS developed at TWMO. Know-how and technical skill on computers and GIS for every technician are contributing significantly such that GIS can be implemented on most of jobs performed at TWMO. Implementations of GIS have been pursued by application modules on a task-oriented basis. Application modules are simple, easy to use, and menu driven with only Chinese. Web-based and mobile GIS are the new components that make water management at TWMO stay on the right course. To solve problems encountered in water management by GIS at TWMO can be easily and user-friendly may be the most important experience.

• Journal of Korean Society on Water Environment
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• v.25 no.1
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• pp.102-111
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• 2009

Turbid storm runoff from intensive highland agriculture area has emerged as the major problem of water quality deterioration in the upstream region of the Han River. High slope of the upland combined with high rate of fertilization and intensive plowing causes high rate of soil erosion, and subsequently high suspended sediment and phosphorus content in the runoff water. The variations of water quality during rain spells were surveyed for two years (2005 and 2006) in the Jawoon Stream that is one of hot spots of intensive horticulture discharging turbid storm runoff. SS and TP showed large increase according to the increase of flow rate, whereas TN and BOD showed less fluctuations. Mean EMCs of SS and TP measured for nine rain events were as high as $207mgSS{\cdot}L^{-1}$ and $0.27mgP{\cdot}L^{-1}$, respectively. The export coefficient of SS and TP per area of cultivated field were calculated as $11,912kgSS{\cdot}yr^{-1}{\cdot}km^{-2}$ and $785kgP{\cdot}yr^{-1}{\cdot}km^{-2}$, repectively, which are significantly higher than reports of other area. It can be concluded that SS and TP in the runoffs were high enough to impose major threat to aquatic habitats, and the highland agriculture should be the main target of water quality management or habitat conservation in the study area.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2008.10a
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• pp.153-161
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• 2008

Agriculture and forest are basis for livelihood in Nepal while both sectors constitute around 40 percent of the national product and over two-thirds of the economically active population is dependent on agriculture. However, radical changes in land use, depletion in crops production and food availability are major threats due to loss of soil fertilityand severe environmental degradation. In this study, we used time series data from 1986/87 to 2005/06 about food crop production and population published by Government of Nepal, Ministry of Agriculture and Cooperatives and Central Bureau of Statistics. Descriptive statistics and ArcGIS were used to assess and map the food security status of Nepalese Terai based on the local food demand and supply system. Food supply to demand ratio(FSDR) was the main idea of assessment. Our results showed that out of 20 districts, only 8 districts were categorised under secured food districts whereas 5 districts were still under food unsecured situation. The analysis further revealed that 7 districts had faced food deficit more than 8-16 times during the last 20 year periods. Data further showed that there was surplus food supply relative to the requirements dictated by FSDR. However, the average FSDR was less than 1.2(less than 20% surplus) exploring fact that most of the districts were not producing sufficient food to cope up the food shock and after 1995 it was relatively stagnant. Our prediction reveals that food supply in Terai even in the future would remain at almost the same level as now, and there will not more than 16-17% surplus by 2021 considering medium vibrant population growth. The findings thus, indicate that Terai may not be a food secure region in the future, even though the region is considered as a food storage house of Nepal. In addition, this paper suggests ways to make future comprehensive case studies more widely comparable in Terai, Nepal.

• Journal of Korean Society of Forest Science
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• v.102 no.3
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• pp.463-466
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• 2013

We examined relationship between rainfall and triggering of shallow landslides in South Korea, based on hourly rainfall data for 478 shallow landslides during 1963-2012. Rainfall intensity(I) and duration(D) relationship was analyzed to obtain the I-D threshold for the initiation of a shallow landslide using the quantile regression analysis. The I-D threshold equation from in this study is: $I=9.64D^{-0.27}$($4{\leq}D{\leq}76$), where I and D are expressed in millimeters per hour and hours, respectively. In addition, rainfall criteria were proposed to predict the potential to cause landslides, based on values of I-D and cumulative rainfall derived from quantile regression analysis. Our findings may provide essential data and important evidences for the improvement of landslide warning and evacuation system.