• Korean Journal of Weed Science
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• v.15 no.3
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• pp.183-187
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• 1995

The germination characteristics of Diplachne fusca (L.) P. Beauv. seeds were investigated under different seed storage conditions to find out reliable system for maintaining the seeds with high and uniform germination rate and thus for possible use of the seeds in herbicide screening with a continuous seed supply. When the seeds were stored under wet-low temperature($4^{\circ}C$) condition, the germination rate was 88% after 4-week-storage. The germination rate slightly declined after the storage for longer than 3 months. Dry seeds stored at room temperature exhibited very low germination rate. The wet-low temperature treatment was effective for inducing the germination of the seeds which had been stored under dry-room temperature condition for 4 months. The germination rate was 70% after 2-week- storage under the wet-low temperature condition. The germination rate was much higher under an alternate temperature condition than under a continuous temperature condition. The optimum temperature was 35/$25^{\circ}C$(14/10hrs). The seeds had a capability to germinate under NaCl-treated condition even at a concentration of 1.0%, whereas the germination of Echinochloa crus-galli seeds was completely inhibited by 0.5% NaCl. This result indicates that D. fusca has an advantage over E. crus-galli to survive in reclaimed 1and from the sea.

• Journal of Korean Society of Forest Science
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• v.33 no.1
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• pp.1-32
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• 1977

This study has been made to find out more effective way of vegetation establishment on severely denuded forest land from the viewpoint of soil moisture regimes. Various environmental factors were measured to estimate soil moisture conditions of different sites. Soil moisture influence on growth of over vegetations, water requirement and drought resistance were analyzed. The efficiency of water use was also reckoned at different fertility levels and different soil moisture conditions. This research is composed of field experiment and green house experiment. Field experiment includes height growth, survival and coverage analysis of cover vegetations (Robinia pseudoacacia L., Lespedeza bicolor Turcz, Arundinella hirta Tanaka var. ciliare Koidzumi.) with 4 fertility level treatments on 3 slopes (Steep: $37^{\circ}$, Moderate: $25^{\circ}$, Gentle; $17^{\circ}$) during dry season (1 April-30 June) and wet season (1 July-10 September). At the same time temperature, relative humidity and precipitation were measured to understand the environmental changes. Soil moisture conditions were measured with soil moisture meter with 24 soil cells. Green house experiment comprised height, fresh weight and dry weight measurements of cover vegetations with 4 fertility levels and 3 moisture conditions for 70 days. The results extracted from experiments are as follews. 1. Cover vegtations have 3 patterns of water requirement at the early stage of growth. a) Robinia type has high water requirement and weaker drought resistance. b) Lespedeza type has low water requirement and stronger drought resistance. c) Arundinella type has moderate water requirement and weaker drought resistance. 2. The vegetations have different optimum fertility levels in different soil moisture supply condition. a) Robinia needs a low fertility level in dry condition and a high level in wet condition. b) Lespedeza needs only low fertility level in all conditions. c) Arundinella needs a low fertility level in dry condition and a high level in wet condition. 3. The efficiency of water use (Water/1g dry weight) by fertility levels is different from one another. Robinia and Arundinella have a good efficiency at low fertility level in dry condition and at high fertility level in wet condition. Lespedeza has a good efficiency at low fertility level in all conditions. 4. $P_2O_5$ requirement of Robinia and Lespedeza is high, but that of Arundinella is low. Soil moisture condition has a great influence on $P_2O_5$ absorption in dendued forest land. Once Vegetations are established on suitable sites with optimum fertitity level according to different moisture condition, even the small amount of soil water in denuded land can he used with high efficiency and the effect of fertility treatment can be maximized.

• Journal of Environmental Impact Assessment
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• v.18 no.2
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• pp.59-67
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• 2009

Water quality of the Lake Youngrang in the Sokcho City is eutrophic. Jangcheon is the largest inflow source to the lake. Major pollutant sources are stormwater runoff from resort areas and various land uses in the Jangcheon watershed. A storm sewer on the southern end of the lake is also an important pollution source. In this study, water quality modelling for Lake Youngrang was carried out considering the rainfall-runoff pollution loads from the watershed. The rainfall-runoff curves and the rainfall-runoff pollutant load curves were derived from the rainfall-runoff survey data during the recent 4 years. The rainfall-runoff pollution loads and flow from the Jangcheon watershed and the storm sewer were estimated using the two kinds of curves, and they were used as the flow and the boundary data of the WASP model. With the measured water quality data of the year 2005 and 2006, WASP model was calibrated. Non-point pollution control measures such as wet pond and infiltration trench were considered as the alternative for water quality management of the lake. The predicted water quality were compared with those under the present condition, and the improvement effect of the lake water quality were analyzed.

• Journal of the Korean Institute of Landscape Architecture
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• v.32 no.1
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• pp.139-156
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• 2004

All Papers on Ecological Landscape Degign in KILA from 1973 to 2003 are listed herein for finding research issues and trends. The emerging field of Ecological studies of landscape design is based on Landscape Ecology and Watershed Ecology, the Principles of which can be applied to surveying and evaluation, Planning and design, construction and management focusing preservation of wildlife habitat and niche. This field can be classified into six categories: 1. Sustainable site planning and index, 2. Ecological planning process and regulation, 3. landscape ecology and biotope map, 4. Watershed and eco corridor project, 5. Urban forestry and environment, and 6. artificial ground and restoration ecology. The following is the summary of the findings from Paper review: 1. Sustainable index shall be studied about more specified sites. Water recycling facilities, and reservation wet land need to be studied. 2. Policy and legislation research on Ecological design shall be researched by expanding of the application field. Nature park planning and management fields shall be considered as the main theme of green networking Parts. 3. Landscape Ecological studies should be connected to practical surveying data, e.g. the eco-maps published by Environment Ministry. Traditional culture and science should be joined with the modem science. 4. Eco-corridor planning will go with the scenarios and theories of watershed ecology. 5. Urban forestry shall be studied with the wildlife's behavior and habitat. 6. Restoration engineering techniques should be reconsidered with the wildlife's existence and environmental affiliation.

• Journal of Ecology and Environment
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• v.30 no.4
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• pp.347-356
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• 2007

The structure and dynamics of Korean red pine stands established in the riparian zone were studied in the Tsang stream in Mt. Seorak National Park, in east-central Korea. Pine stands were classified into four successional stages, the initial, establishing, competitive, and stabilizing stages, based on the age distribution of a dominant tree, Pinus densiflora, the vegetation stratification, and the microtopography of the riverine environment. The stages usually corresponded to disturbance frequencies, depending on the horizontal and vertical distances from the watercourse. Stands of the initial and establishing stages lacked tree or subtree layers, or both. As stands progressed through the developmental stages, soil particle size became finer and moisture retention capacity was improved. The stand ordination reflected the developmental stage, and the species ordination differentiated species specializing in relatively dry and wet habitats. The results of the analysis of vegetation dynamics provided ecological information which will be useful for understanding the developmental processes of vegetation established in riparian zones. Species diversity indices usually increased across developmental stages, following the typical pattern for successional processes. We discuss the importance and necessity of riparian vegetation in Korea, where most riparian forests have disappeared due to excessive human land use.

• Journal of Environmental Science International
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• v.17 no.2
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• pp.257-267
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• 2008

Groundwater recharge characteristics in a fractured granite area, Mt. Geumjeong, Korea. was interpreted using bedrock groundwater and wet-land water data. Time series analysis using autocorreclation, cross-correlation and spectral density was conducted for characterizing water level variation and recharge rate in low water and high water seasons. Autocorrelation analysis using water levels resulted in short delay time with weak linearity and memory. Cross-correlation function from cross-correlation analysis was lower in the low water season than the high water season for the bedrock groundwater. The result of water level decline analysis identified groundwater recharge rate of about 11% in the study area.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.7
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• pp.961-967
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• 2018

Lao-native beef cattle are primarily Bos indicus, and most ruminant production in Laos is still dominated by small-scale or backyard producers that use traditional practices, resulting in low productivity. The cattle herd size in Laos has grown by an average of 5 percent per year from 1.52 million in 2010/11 to 1.81 million in 2014/15. In 2016, the Laos cattle population was 1.88 million head, with smallholder farmers representing 98% of production despite efforts by the Laos government to develop commercial-scale farms. There were 170 commercial cattle farms in 2016, with 56 percent in the Central region of Laos. Although, overall, ruminant meat production has tended to increase but with consumption at 7.29 kg/capita/yr in 2013, it remains insufficient to meet demand. Crop residues and agro-industrial by-products used in ruminant diets include rice straw, cassava pulp and wet brewers' grains as roughage, energy and protein sources, respectively. The Belt and Road Initiative proposed by China in 2013 will connect China closely with all countries in Southeast Asia. This initiative will change landlocked Laos to land linked for investors who will benefit from convenient transport at a lower cost, promoting agricultural production in Laos.

• Journal of Environmental Impact Assessment
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• v.9 no.4
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• pp.339-348
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• 2000

This study was conducted to investigate the distribution pattern of plants on the streamside of Goggyochun, and to survey the distribution of heavy metal-contaminated soils and plants. A total of 11 survey sites were selected along the Goggyochun during the period of between June and September 1999. The wet land plants were composed of 44 species. The most frequently occurring species in the study sites were Rumex crispus, Persicaria hydropiper, Cyperus amuricus and Setaria viridis, and among them the Humulus japonicus, Erigeron canadensis and Phragnites communis species were dominants of the community. Analysis of soil properties showed that organic matter and clay contents were higher in the upstream region while sand content was higher in the downstream region. The pH and the organic matter contents of soils were at range of 6.70-9.94 and 2.39-15.16% respectively. The average contents of Pb and Cd in soils were 11.96mg/kg and 1.64mg/kg respectively, and these values were higher as compared with those of ordinary soil in Korea. The average contents of Zn and Pb in Persicaria hydropiper were 8.30mg/kg and 7.38mg/kg respectively, and these values were higher than other plants. The distribution of heavy metals in plants varied in accordance with the species regardless of the sites.

• Atmosphere
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• v.21 no.4
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• pp.361-371
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• 2011

In this study, characteristics and trends of tropical night (TN) are investigated by using the KMA 14 observation data for the recent 50 years (1958-2007) over South Korea. The TN is defined as a day with a daily minimum temperature exceeds the absolute threshold temperature ($25^{\circ}C$), and the relative deviation from normal temperature, 95th percentile of all observed daily minimum temperature. Although the spatial distribution of TN occurrence depends on the choice of the definitions, the frequency of TN shows strong spatial and interannual variations with the minimum at high land area (Chupungnyeong and wet years) and maximum at southern coastal area and large city area (Jeju, Busan, Seoul, Daegu). Most of TN occurs in August (56%) and July (41%), and the duration date of TN is proportional to the frequency of TN without regard to the definition method. In general, increasing trends are found in the TN time series without regard to the analysis method, but the trends are clearly depending on the analysis period and geographic locations. Decreasing trends are prominent during the most of analysis period, especially until the mid of 1990, whereas strong increasing trends are found during recent 30 years (1988-2007), especially at Jeju, Ulsan, Daegu and Pohang. Also the severity of TN is significantly increased in recent years.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.12
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• pp.1779-1787
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• 2000

Southern and south-western Australia is a typical mediterranean environment, characterised by wet, cold winters and dry, hot summers. The evaporation rate varies significantly in summer, resulting in a high salinity of drinking water for grazing animals. In addition, a large amount of land in the cropping areas is affected by salt. Puccinellia, tall wheat grass and saltbushes have been planted to improve the soil condition and to supply feed for grazing animals. Animals grazing these areas often ingest an excessive amount of salt from soil, forage and drinking water which can reduce feed intake, increase the water requirement, depress growth and affect body composition as demonstrated in sheep. While the deer industry has been successfully developed in these regions, the potential impact of excessive salt intake on deer production is unknown. The salt tolerance has been well defined for sheep, cattle and other livestock species, but the variation between animal species, breeds within species, maturity status and grazing environments makes it impossible to apply these values directly to deer. To optimise deer production and effectively use natural resources, it is essential to understand the salt status of grazing deer and the impact of excessive salt intake on growth and reproduction of deer.