• Journal of The Korean Society of Grassland and Forage Science
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• v.41 no.3
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• pp.168-175
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• 2021

The optimal determination of seeding rate is critical to minimizing uncertainties about the large variations observed in forage quality and productivity when alfalfa is cultivated under different geographical areas and growing conditions. The objective of this investigation was to provide information about the proper seeding rate according to harvest timing for alfalfa cultivation in the Northern regions of Korea. Alfalfa was sown in September 2018 at a seeding rate of 20, 30 or 40 kg/ha and harvested four times in 2019: May 3, July 2, September 11, and October 13. Regardless of seeding rate, alfalfa plant height was longest at the third harvest (113 cm) and the shortest in the last annual harvest (43.8 cm). However, seeding rate had no effect on alfalfa plant height at any harvest. Forage relative feed value was increased in the first cutting but decreased in the third cuttings as seeding rate increased. However, seeding rate had slight effect on alfalfa forage quality components at the second and fourth cuttings. Total annual DM and crude protein production (in 4 harvests) was greater at higher seeding rates. Plots seeded at a rate of 40 kg/ha produced on average 1,257 and 2,620 kg/ha more forage (DM basis) than those seeded at a rate of 30 or 20 kg/ha, respectively. Forage DM production at the first, second, third, and fourth harvests accounted for 36.1, 24.0, 27.1, and 12.8 % of total annual DM production, respectively. Overall, small differences were seen when alfalfa seeding rate was different but maximum forage DM production (in four harvests) was detected when seeding rate was 40 kg/ha. These data could be useful to the alfalfa growers by allowing them to make more accurate trade-offs between seed price and the expected magnitude of forage yield gains in order to select the best seeding rate.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.53-53
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• 2019

Cypripediums, popularly called lady's slippers or moccasin flowers, are the showiest and most sought after hardy terrestrial orchids, collected and grown by orchid and alpine plant enthusiasts alike. In Korea, 4 species of cypripedium are reported as Cypripedium japonicum, C. macranthos, C. guttatum, and C. calceolus. We had already reported the feasibilities of C. macranthos and C. guttatum with in vitro germination methods from immature seeds. The seeds of white lady's slipper orchid (Cypripedium macranthos Sw. alba) were collected 65 days after pollination in 2018. The green pods were sterilized with flame and sowed immediately on the POM(Phytomax orchid maintenance media(R), Sigma) supplemented with BAP 0, 0.5, 1.0 mg/L and NAA 0, 1, 2mg/L. The germination of seed was observed 90 days after sowing, and the plantlets were subcultured to the same media according to the size of the protocorm with 1~2, 2~3, 3~4, 5~6, 7~8mm. The time of the subculture to the new media seems to be critical factors of forming rhizoids which is the hairy root of the cypripediums. As a results, the protorms of the white lady's slipper orchid was successfully germinated in the POM media supplemented BAP 0.5 and NAA 1.0 mg/L. The roots and rhizoids were formed in 5~6mm protocorms subculture over 95% survival ratio. We also tried to subculture to liquid medium without activated charcoal, however the browning or malformation of the roots was observed in the root. The formation of shoots from the protocorm was effectively enhanced in the POM media with non-additives of plant growth regulators. These results indicate the possibility of high and stable production and practical industrialization of endangered white lady's slipper orchids.

• Journal of Climate Change Research
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• v.4 no.2
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• pp.189-199
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• 2013

Using meteorological data collected from 60 observation stations during the last 38 years from 1973 through 2010, we have analysed the occurrence frequencies of abnormally low or high temperature leading to agrometeorological disasters. The analysis was made for 20 agro-climatic zones that had already been divided by the Rural Development Administration before. Since 1973, there have been an average of 1.8 frequency of abnormal air temperature occurrence per year. The frequency of abnormally high temperature occurrence has increased from an average of 0.2 per year in 1970s to 1.0 in 2000s. However, the frequency of abnormally low temperature occurrence has decreased from an average of 2.06 per year in 1970s to 0.63 in 2000s, which might be able to explain a recent global warming. The highest frequency of abnormally high temperature occurrence appeared in Taebaek Alpine zone with an average of 0.76 frequency per year. Meanwhile, abnormally low temperature was the highest in Western Sobaek Inland zone with an average of 1.43 frequency per year.

• Journal of the Mineralogical Society of Korea
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• v.32 no.1
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• pp.15-39
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• 2019

An ultramafic complex occurs as an isolated lenticular body in the Andong area. The Andong ultramafic complex comprises ultramafic and mafic rocks, but mainly peridotites. The complex extends for several kilometer to ENE direction, adjacent to the Andong fault line. This study is for petrochemistry of the peridotites within the ultramafic complex and characteristics of asbestos occurrences. The peridotites are igneous origin, ranging from lherzolite to wehrlites and are characterized by high Fo olivine ($Fo_{0.85-0.87}$), Mg clinopyroxene ($Mg_{87.5-93.5}$), and tremolitic to tschermakitic hornblende. Geochemically, these rocks show high magnesium number (mainly Mg = 85.3-87.38) and transitional element and low alkali element contents. The peridotites host asbestos, including chrysotile, tremolite and actinolite asbestos, but dominated by amphibole asbestos. The amphibole asbestos are found along small fault face, and cleavage and fracture showing several cm to ten cm in width as slip and oblique fibers, while the chryostiles occur at cleavage and vein showing several mm-cm in width as cross and slip fibers. They are confirmed by PLM, XRD and SEM results. Overall characteristics of peridotites from the Andong ultramafic complex and occurrences of the asbestos are similar to those of worldwide orogenic related Alpine type ultramafic rocks and serpentinized ultramafic bodies in Chungnam, Korea, respectively.

• Journal of Korean Society of Forest Science
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• v.100 no.4
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• pp.565-576
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• 2011

This study was conducted to describe forest stand characteristics of the habitats of Allium victorialis var. platyphyllum population from the ecological analysis of classification of vegetation types, importance values, species diversity, interspecific association and community similarity in Ulleung Island and Mt. Hambaek, in which investigated by 48 plots ($10m{\times}10m$). The vegetation studied was classified into 1 community group, 2 communities, 2 groups and 3 subgroups for a species unit and divided by 5 units for a vegetation unit. In the Fagus engleriana group (vegetation unit 1, 2 and 3), importance value of A. victorialis var. platyphyllum in herb layer showed relatively higher value than other units. Importance value of A. victorialis var. platyphyllum in herb layer had higher value. In the analysis of interspecific association, most of the species associated positively to A. victorialis var. platyphyllum belonged to habitat features of valley area and sub-alpine zone. Therefore, it was considered that the growing environment of A. victorialis var. platyphyllum population was closely correlated to soil moisture and air humidity.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.5
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• pp.578-585
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• 1996

This experiment was carried out to obtain the basic informations on yield performance and physicochemical quality properties of North Korean rices at southern high altitude area, Unbong and southeren plain area, Iksan. North Korean cultivars showed significant difference in number of spikelets per panicle, percentage of ripened grain and yield between two locations, but not significant in number of panicle per hill and l000-grain weight. The highest contribution to grain yield was the percentage of ripened grain and l000-grain weight at Iksan and Unbong, respectively, The protein, amylose content, alkali digestion value and Mg/K ratio showed larger variation in varieties than that in the locations cultivated. Mg and K revealed highly significant variations in locations, varieties and variety $\times$ location (V$\times$L) interaction. The amylogram characteristics such as initial pasting temperature, peak, breakdown, setback and consistency viscosities showed highly significant variation in locations, varieties and V$\times$L interaction. The physical characteristics of cooked rice such as adhesiveness, gumniness and chewiness also showed highly significant variations in locations, varieties and V$\times$L interaction.

• Journal of the Korean Geographical Society
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• v.30 no.1
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• pp.1-13
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• 1995

One of the oldest fossil of conifers and taxads in the Korean peninsula includes Elatocladus, Ullmannia, Walchia and dates back to the Permian period of the Palaeozoic era. The only conifer which successfully survived since the Cretaceous period is Pinus and still thrives in Korea. The extinction of Miocene conifers, such as Sciadopitys, Taxodiaceae, Metasequoia and Cryptomeria may due to the climatic deteriorations during the late Pleistocene period. However, the cryophilous conifers and taxads, e.g..Pinus, Juniperus, Abies, Picea, Cupressaceae, Larix and Taxus continued to exist from the Miocene to the late Pleistocene and became major vegetational elements in the mountainous areas of Korea. As the temperature ameliorates in the late Holocene period, thermophilous Pinus (Diploxylon) gradually had increased in numbers and became a dominant vegetation in the lowland and montane areas since 2,000 years B.P. in korea. Out of various Korean conifers and taxads, Pinus which surviving since the Cretaceous period of Mesozoic era, ranges spatially from southern coastal area to northern alpine belt of the Korean peninsula. Pinus which contains largest species number in conifers is one of the most well-adapted genus to the Korean environment. The next important conifer Juniperus dates back to the Miocene period of Cenozoic era and continuously maintains speciation and expansion of distributional range. Other major conifers and taxads of Korea include Picea, Abies, Lorix and Taxus. The restriction of distributional range of Cephralotaxus and Tsuga may due to the climatic deterioration during the Pleistocene period of Cenozoic era. The patterns of the temporal and spatial distribution of Korean conifers and taxads may provide invaluable informations for the better understanding of present-day distributional range and ecology.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.6
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• pp.766-773
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• 2011

The objective of the present study was to examine whether yaks possess any adaptive mechanisms of nitrogen (N) metabolism to survive in the harsh foraging environment of the Qinghai-Tibetan Plateau. A grazing experiment on native alpine meadows was conducted to determine availability of herbage biomass and body weight (BW) change of yaks over the year, followed by two indoor feeding trials to investigate adaptation mechanisms of N metabolism in yaks fed at similar intake level to grazing conditions. Three castrated males of each of three genotypes; yak (Bos grunniens), indigenous cattle (Bos taurus) and their crossbred - cattleyak (Bos taurus male${\times}$Bos grunniens female), were used in the housed trials. Results showed that: i) Monthly herbage biomass production and daily grazing intakes by yaks over the year ranged from 220 to 4,664 kg DM per ha, and 1.90 to 8.50 kg DM, respectively. For about seven months each year, yaks suffer from malnutrition as a result of inadequate pasture conditions; ii) Urinary N excretion and N retention by yaks were significantly affected by feeding level, and yaks had a lower (p<0.05) average daily urinary N excretion (0.39 g/kg $BW^{0.75}$) and a greater (p<0.05) N retention (-0.09 g/kg $BW^{0.75}$) than indigenous cattle (0.47 and -0.16 g/kg $BW^{0.75}$, respectively). Fasting daily urinary N excretion was greater (p<0.05) for indigenous cattle than yaks (353 vs. 248 mg/kg $BW^{0.75}$). Purine derivative N excretion and purine derivative N index (PNI) increased with increasing feeding level, while the value of PNI was greater (p<0.05) for yaks and cattleyak (0.11 and 0.12, respectively) than for indigenous cattle (0.09) during the feeding trials. These results suggest that yaks could rely, in part, on the recycling of N to adapt to the harsh forage environment on the Qinghai-Tibetan Plateau.), were used in the housed trials. Results showed that: i) Monthly herbage biomass production and daily grazing intakes by yaks over the year ranged from 220 to 4,664 kg DM per ha, and 1.90 to 8.50 kg DM, respectively. For about seven months each year, yaks suffer from malnutrition as a result of inadequate pasture conditions; ii) Urinary N excretion and N retention by yaks were significantly affected by feeding level, and yaks had a lower (p<0.05) average daily urinary N excretion (0.39 g/kg $BW^{0.75}$) and a greater (p<0.05) N retention (-0.09 g/kg $BW^{0.75}$) than indigenous cattle (0.47 and -0.16 g/kg $BW^{0.75}$, respectively). Fasting daily urinary N excretion was greater (p<0.05) for indigenous cattle than yaks (353 vs. 248 mg/kg $BW^{0.75}$). Purine derivative N excretion and purine derivative N index (PNI) increased with increasing feeding level, while the value of PNI was greater (p<0.05) for yaks and cattleyak (0.11 and 0.12, respectively) than for indigenous cattle (0.09) during the feeding trials. These results suggest that yaks could rely, in part, on the recycling of N to adapt to the harsh forage environment on the Qinghai-Tibetan Plateau.

• Korean Journal of Environment and Ecology
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• v.34 no.5
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• pp.358-371
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• 2020

As climate change is expected to lead to a severe reduction of biodiversity, studies to investigate the reasons for habitat loss, growth decline, and death of Korean fir (Abies koreana Wilson), endangered alpine/subalpine species in Korea, have been conducted for years but found no clear answer yet. This study reviewed previous studies on Korean fir published in the journals in the past 40 years, 1980 through 2020, into 10-year units, examined the study trend by period, region, and subject with a focus on ecological studies, and analyzed the study results. The ecological studies were categorized into evolutionary ecology, physiological ecology, population ecology, and landscape ecology. Based on the results, we suggested the required research fields in the future. We found a total of 73 papers published in the past 40 years and 48 (65.8%) of them published in the past 10 years. In terms of region, Mt. Halla accounted for the most as 41 papers were on it. In terms of ecological subjects, the physiological ecology accounted for the most with 38, and the evolutionary ecology accounted for the least with 10. The review of the study results showed that many studies identified water stress caused by the water resource imbalance due to temperature increase and spring precipitation reduction following climate change as the main reason for the decline and habitat loss of Korean fir. However, recent studies suggested other factors, such as soil environment, disturbing organisms, and climatic events. The cause of the decline and death of the Korean fir not yet being clearly identified is that most of the studies dealt with the basic content, were carried out intermittently, and were concentrated in some regions. Therefore, we need long-term studies with advanced technology in each study subject at a local scale to find the cause of Korean fir decline and present sustainable management and conservation. Moreover, it is necessary to extend our study subjects to ecosystem ecology and systems ecology to integrate the results from various study subjects for a comprehensive understanding of the reason for Korean fir declines. The results of comprehensive studies could provide clearer answers for Korean fir's declines and the alternatives of conservation management and practices.

• Economic and Environmental Geology
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• v.6 no.1
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• pp.29-64
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• 1973

A land resources survey in the semi-arid area, Mula in S. E. Spain, of $400km^2$ is compiled. The basic aim of the project is to investigate the intrinsic qualities of the land resources of the area by means of applying an integrated method of natural resources survey mainly concerning with analysis and synthesis of land complexes, each of them represents an area or a group of areas with similar patterns of landforms, soils and vegetation, based on a geomorphological approach. The area is characterized by a linear arrangement of relief pattern with an asymmetric homoclinal repetition of slope attitudes elongating WSW-ENE, dipping steeply on the NW sides and gently on the SE sides, which have been resulted from the post-Alpine folding of the Triassic to Cretaceous limestone, the Eocene limestone, the Oligocene sandstone and the lower Miocene limestone and marl, and the post-lower Miocene faulting, tilting and subsequent differential erosion of the Miocene sedimentary formations. An integrated body of information in geology, landforms, soils and vegetation, which are significantry interrelated as an environmental complex, has been obtained. Using this data, 26 land complexes developing on the various situations of landforms, such as folded mountain ranges, tilted tablelands, bevelled cuestas, degraded hill-lands associating with enormous foots lopes, undulating terrains and terraced or flat plains, have been differentiated, mapped and described. The soils of the area are mostly light colored calcic lithosols which have been derived dominantly from the marly parent materials and developed into remarkable slope catenas in some places depending on the relief conditions. The land uses of the area are mainly characterized by the perennially irrigated cultivation of citrus orchards along the terraced alluvial deposits fringing the Segura and Mula River, and the dry-land cereal cultivation on gentler slopes. Pioneer dry-land cultivations within the shrubs on steeper slopes are restricted to the unchannelled tributary drainage floors. The availability of water is a fundamental controlling factor for existence of native and cultivated vegetation as a whole, and a number of active processes including sheet wash and gully erosion, especially on the scarp slopes, are the other important factors to be considered in conservation and management of the land in the area.