• Journal of the Korean earth science society
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• v.31 no.6
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• pp.541-554
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• 2010

Fifteen min-microtremor data sets were collected at 136 sites from a coastal area of Kunsan and 117 sites from an inland area of Jeonju located in SW Korea, and were analyzed for the HVSR (Horizontal to Vertical Spectral Ratio) of the sites. The microtremor spectra of the coastal area have stronger energy in the lower frequency range from 1-6 Hz than those of the coastal area. This result can be attributed to the effect of the waves and tides in the Keum river and the Yellow sea. Twenty four hours of measurement of the microtremor indicated that the microtremor spectrum correlates with the human activities, but the microtremor HVSR peak was observed consistently at the characteristic frequency for the site. The HVSR peaks were grouped into 4 types -"single peak", "double peak", "broad peak" or "no peak"- based on their shapes. More than 90% of the data sets exhibit peak frequencies ($F_0$) which can be easily identified. The distribution of $F_0$ reveals a close relationship with the topography and local geology of the areas, exhibiting high F0s in the hillside areas and low $F_0s$ in the reclaimed land area. While the amplitudes of microtremor HVSR peak frequencies are less than 4 in the downstream of the inland area, those of the recently reclaimed land in the coastal area are extremely high (more than 10). The results of this study indicate that detailed HVSR studies are essential for the earthquake hazard reduction of reclaimed lands.

• Journal of Plant Biology
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• v.7 no.2
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• pp.9-13
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• 1964

As to the up-lnd bamboos, I have reported, in my previous works, that Korea has two species in the genus of Pseudosasa, four in Pleioblastus, and other four in Sasa. In the present work, I dealt with Sasamorpha Purpurascens Nakai var. Borealis Nakai which proved the strongest vitality of all up-land bamboo yet found in various up-lands of Korea, and which might be most important from the utility view-point. This report is chiefly on its procreation. Sasamorpha Purpurascens Nakai var. Borealis Nakai can be found almost everywhere throughout the country, and its leaves and stems are much used in farms in various forms of manufacture. It is also welcomed as the feed for livestocks and as cover plants for aforestation, especially as the excellent means of errosion control on devastated hill sides. It is also widely accepted that it will provide, in the immediate future, abundant sources for the up-land bamboo pulp. As the first phase of my research plan on the subject, I undertook to determine the possible best way of its procreation, for which were included the experiments of inducing the growth of subterranean stems, the entire stand cutting, transplanting, reclaimed planting after burning etc. in order to observe the plant elongation, growing conditon, climatical effect etc. What has been fuond out so far given here as follows: 1) Of the various sections of the country, Mt. Odae area gives out the most excellent Sasamorpha Purpurascens Nakai var. Borealis Nakai(the leaf weight of which is 450 gr.) and Taekwanryong area comes the next class. This species can be transplanted anywhere in the South Korea. 2) The elongation of S.P. Nakai var. Borelais begins at around the middle of May and almost completely stops by the 20th of August. 3) The best studied transplanting season is supposed to be Feb. -April, for those transplanted during that period proved 100% of success. The next best transplanting season may be October. Rain fall does not have so much effect on transplanting as the growing season does. 4) In inducing the subterranean stems, the growing season can be ignored. The root expnsion is most animated during the months of April-June, the most active season for water absorption. Those stems induced during the winter proves more rapid growth. 5) The entire stand cutting shows greater growth than the reclaimed planting after burning and that, the growth is most vigorous during May-July, whereas during the hottest months of Aug-Sept. the growth shows only 5 cm. The new shoots grow slower both in the field of entire stand cutting and in the field of reclaimed planting after burning than in the otherwise fields.

• Journal of the Korean association of regional geographers
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• v.3 no.2
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• pp.37-87
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• 1997

As a results of researches on the cultivation processes and settlement developments on the Mangyoung river valley as a whole could be have four 'Space-Time Continuity' through a [Origin-Destination] theory model. On a initial phases of cultivation, the cultivation process has been begun at mountain slopes and tributory plains in upper part of river-basin from Koryo Dynasty to early Chosun Dynasty. At first, indigenous peasants burned forests on the mountain slopes for making 'dryfield' for a cereal crops. Following population increase more stable food supply is necessary facets of life inducing a change production method into a 'wetfield' in tributory plains matching the population increase. First sedentary agriculture maybe initiated at this mountain slopes and tributory plains on upper part of river basin through a burning cultivation methods. Mountain slopes and tributory plains are become a Origin area in cultivation processes. It expanded from up to down through the valleys with 'a bits of land' fashion in a steady pace like a terraced fields expanded with bit by bit of land to downward. They expanded their land to the middle part of river basin in mid period of Chosun Dynasty with dike construction techniques on the river bank. Lower part of river cultivated with embankment building techniques in 1920s and then naturally expanded to the tidal marshes on the estuaries and river inlets of coastal areas. 'Pioneer fringes' are consolidated at there in modern times. Changes in landscapes are appeared it's own characters with each periods of time. Followings are results of study through the Mangyoung river valley as a whole. (1) Mountain slopes and tributory plains on the upper part of river are cultivated 'dryfields' by indigenous peasants with Burning cultivation methods at first and developed sedentary settlements at the edges of mountain slopes and on the river terrace near the fields. They formed a kind of 'periphery-located cluster type' of settlement. This type of settlement are become a prominant type in upper part of river basin. 'Dryfields' has been changed into a 'wetfields' at the narrow tributory plains by increasing population pressure in later time. These wetfields are supplied water by Weir and Ponds Irrigation System(제언수리방법). Streams on the tributory plains has been attracted wetfields besides of it and formed a [water+land] complex on it. 'Wetfields' are expanded from up to downward with a terraced land pattern(adder like pattern, 붕전) according to the gradient of valley. These periphery located settlements are formed a intimate ecological linkage with several sets of surroundings. Inner villages are expanded to Outer villages according to the expansion of arable lands into downward. (2) Mountain slopes and tributory plains expanded its territory to the alluvial deposited plains on the middle part of river valley with a urgent need of new land by population increase. This part of alluvial plains are cultivated mainly in mid period of Chosun Dynasty. Irrigation methods are changed into a Dike Construction Irrigation method(천방수리방법) for the control of floods. It has a trend to change the subjectives of cultivation from community-oriented one who constructed Bochang along tributories making rice paddies to local government authorities who could be gather large sums of capitals, techniques and labours for the big dike construction affairs. Settlements are advanced in the midst of plains avoiding friction of distances and formed a 'Centrallocated cluster type' of settlements. There occured a hierarchical structures of settlements in ranks and sizes according merits of water supply and transportation convenience at the broad plains. Big towns are developed at there. It strengthened a more prominant [water+land] complex along the canals. Ecological linkages between settlements and surroundings are shaded out into a tiny one in this area. (3) It is very necessary to get a modern technology of flood control at the rivers that have a large volume of water and broad width. The alluvial plains are remained in a wilderness phase until a technical level reached a large artificial levee construction ability that could protect the arable land from flood. Until that time on most of alluvial land at the lower part of river are remained a wilderness of overgrown with reeds in lacks of techniques to build a large-scale artificial levee along the riverbank. Cultivation processes are progressed in a large scale one by Japanese agricultural companies with [River Rennovation Project] of central government in 1920s. Large scale artificial levees are constructed along the riverbank. Subjectives of cultivation are changed from Korean peasants to Japanese agricultural companies and Korean peasants fell down as a tenant in a colonial situation of that time in Korea. They could not have any voices in planning of spatial structure and decreased their role in planning. Newly cultivated lands are reflected company's intensions, objectives and perspectives for achieving their goals for the sake of colonial power. Newly cultivated lands are planned into a regular Rectangular Block settings of rice paddies and implanted a large scale Bureaucratic-oriented Irrigation System on the cultivated plains. Every settlements are located in the midst of rice paddies with a Central located Cluster type of settlements. [water+land] complex along the canal system are more strengthened. Cultivated space has a characters of [I-IT] landscapes. (4) Artificial levees are connected into a coastal emnankment for a reclamation of broad tidal marshes on the estuaries and inlets of rivers in the colonial times. Subjectives of reclamation are enlarged into a big agricultural companies that could be acted a role as a big cultivator. After that time on most of reclamation project of tidal marshes are controlled by these agricultural companies formed by mostly Japanese capitalists. Reclaimed lands on the estuaries and river inlets are under hands of agricultural companies and all the spatial structures are formed by their intensions, objectives and perspectives. They constructed a Unit Farming Area for the sake of companies. Spatial structures are planned in a regular one with broad arable land for the rice production of rectangular blocks, regular canal systems and tank reservoir for the irrigation water supply into reclaimed lands. There developed a 'Central-located linear type' of settlements in midst of reclaimed land. These settlements are settled in a detail program upon this newly reclaimed land at once with a master plan and they have planned patterns in their distribution, building materials, location, and form. Ecological linkage between Newly settled settlemrnts and its surroundings are lost its colours and became a more artificial one by human-centred environment. [I-IT] landscapes are become more prominant. This region is a destination area of [Origin-Destination] theory model and formed a 'Pioneer Fringe'. It is a kind of pioneer front that could advance or retreat discontinously by physical conditions and socio-cultural conditions of that region.

• Journal of the Korean association of regional geographers
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• v.10 no.2
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• pp.479-496
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• 2004

This study attempts to examine Egyptian agricultural development with regard to the social and political changes in the Egypt, and tries to explore the patterns of major crops and those spatial distribution nowadays. Also, land reclamation processes and farming activities are explained. Agricultural development in Egypt has been considerably affected by historical international trade, and those crops such as cotton and sugar cane have been especially protected and controlled as strategic crops by the Egyptian governments. The issues of land ownership have been varied with political environments by periods, but the controls to the strategic crops have been consistently maintained to a degree though some variations. since the 1990s, national liberalization programs also caused to change the agricultural policies which have affected the adjustments of crop production and land use. Spatial distribution of major crops and farming activities are examined in relation to natural environments by Delta, Middle and Upper Egypt, desert areas. The projects of land reclamation after 1952 are evaluated with the effects of government intervention, and the actors in use of the reclaimed lands are investigated.

• Korean Journal of Environment and Ecology
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• v.36 no.6
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• pp.684-692
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• 2022

This study was conducted to assess ecosystem services provided for Saemangeum agricultural and life sites and surrounding areas and establish measures to enhance them. The ecosystem services in the Saemangeum region were found to be different depending on its land use type. Before reclamation, the quality of ecosystem service in the Saemangeum region was high in all aspects: supply, control, culture, and support service functions. After the reclamation, however, the quality of supply, regulating, and support services declined. Therefore, it is necessary to enhance the quality of regulating and support services provided by semi-natural habitats such as rice paddy and reservoirs to improve the ecosystem service of the Saemangeum agricultural and life site. The suggested service improvement includes transforming natural ecosystems, such as forests and rural areas, and vast agricultural land into rural tourism and ecotourism and strengthening cultural service functions centered on education and research related to agriculture. To this end, it is necessary to utilize large agricultural land and agricultural infrastructure to promote agricultural production and rural tourism and government support for areas where the aging population is a problem.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.3
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• pp.502-509
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• 2011

It is important to determine optimum soil covering depths for tree survival and growth because soil covering depths for establishing tree planting bases in coastal reclaimed lands are related to the costs for soil collection, transportation and land reclamation. The objectives of this study were carried out to determine optimum soil covering depths for the normal growth of planted trees in a coastal reclaimed land. The study sites were located in Asan National Industrial Complex in Pyeongtaek City, Gyeonggi-do. Four tree species (Pinus thunbergii, Chamaecyparis pisifera, Zelkova serrata, Quercus acutissima) with one hundred eighty trees of each species were planted in various depths of soil covering (no soil covering, 0.5 m, 1.5 m, 2.0 m soil covering treatments) on April 1998, and the tree growth patterns were measured on September 2000. The change of soil properties, tree mortality rate, root collar diameter and height growth were measured from each soil covering depth treatment on September 2000. Soil pH, EC, exchangeable cations ($K^+$, $Na^+$, $Ca^{2+}$, $Mg^{2+}$), anion $Cl^-$, and base saturation increased with decreased soil covering depths. The mortality rates of tree species showed decreased with increased soil covering depths. The height growth of tree species increased with increased soil covering depths. Height growth of Pinus thunbergii was significantly different between the soil covering depth below 0.5m and other three covering depths, while the growth of other species (C. pisifera, Z. serrata, Q. acutissima) was significantly higher in soil covering depths below 1.5 m than in other soil covering depth treatments. The root collar diameter growth of all tree species showed increasing trends with increased soil covering depths. It is recommended to cover the soil depths above 1.5 m to decrease mortality and to stimulate the tree growth of C. pisifera, Z. serrata and Q. acutissima, while P. thunbergii which is a salt tolerate species could be planted in the 1.0 m soil covering depth.

• Magazine of the Korean Society of Agricultural Engineers
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• v.14 no.1
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• pp.2535-2548
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• 1972

Instead of fertilizing the lands they moved to find other fertile lands and lived a feudal life agriculture and various machincs played a main role in the land reclamation. The best method of land clearing, the time and capacity in the operation and the effect of growing crops should systematically analized prior to the time of 3rd Five-year Economic Development(1972-1976) in order to cultivate 210,000ha of wasteland or the modernization of our country. The present study was investigated to find out a new working-system of mechanical land clearing and development of fertile soil. The results are as follows: 1) The first stage of productive power increases when weeds were mixed soil in the land clearing work in order to supply organic materials and to make soil swollen instead of burning or just removing. 2) The equipments such as bulldozers, harrows, power tillers and so on should be prepared in order to do a systematic work in the land clearing. 3) The work of pulling-up roots is dependent upon the forms of roots spreading under the ground. The work of the pulling-up of the straight roots was most difficult. But before the roots are pulling-up we do not know the forms of roots. 4) The cutting of soil from upside to under side land clearing method (II) Spent 6 hr 7 min 43 sec per 1 Danbo in doing land clearing and control method spent 4 hr 52 min 30 sec per 1 Danbo in doing land cearing. No significant difference could be found between II treatment type and I treatment type. 5) The volume of soil carried by bulldozer $270.38m^3$ per 1 Danbo in I type and in II type, $368.58m^3$ per 1 Danbo or about 36% increased in II type then in I type. But that is not a significant difference when considering the whole productive power of soil. 6) The land clearing of terrace by bulldozers cannot escape making the embankment slope of about $45^{\circ}$, and 25.3% should be decreased in the area. It is recommended to make use of the embankment slope by planting grass for cows. 7) The time of retary tilling increased 2.3 times or 1 hr 42 min 22 sec per 1 Danbo compared to the timesrequired in the harrowing. Because it mixed the Organic matter on ground and the harrowing of subsoil. 8) The havest of pasture growing on the land reclamation in natural slope is as follows. (a) The none fertilizers with reclaimed block of productivity decresed 1/10 than that of the farmland. Therefore the none fer tilizing in the cultivated pasture is unprofitable. (b) The havest of the manured IV treatment block was the best not only in the kinds of fertilizers but also in the kinds of pasture grass.

• Korean Journal of Agricultural and Forest Meteorology
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• v.24 no.3
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• pp.133-144
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• 2022

This study was conducted to investigate the cultivation period, adaptive genetic resources, growth and development patterns, and water consumption for rice cultivation in the desert environment of United Arab Emirates (UAE). R esearch on rice cultivation in the desert environment is expected to contribute to resolving food shortages caused by climate change and water scarcity. It was found that the optimal cultivation period of rice was from late November to late April of the following year during which the low temperature occurred at the vegetative growth stage of rice in the UAE. Asemi and FL478 were selected to be candidate cultivars for temperature and day-length conditions in the desert areas as a result of pre-testing genetic resources under reclaimed soil and artificial meteorological conditions. In the desert environment in the UAE, FL478 died before harvest due to the etiolation and poor growth in the early stage of growth. In contrast, Asemi overcame the etiolation in the early stage of growth, which allowed for harvest. The vegetative growth phases of Asemi were from early December to early March of the following year whereas its reproductive growth and ripening phases were from early March to late March and from late March to late April, respectively. The yield of milled rice for Asemi was 763kg/10a in the UAE, which was about 41.8% higher than that in Korea. Such an outcome was likely due to the abundant solar radiation during the reproductive growth and grain filling periods. On the other hand, water consumption during the cultivation period in the UAE was 2,619 ton/10a, which was about three times higher than that in Korea. These results suggest that irrigation technology and development of cultivation methods would be needed to minimize water consumption, which would make it economically viable to grow rice in the UAE. In addition, select on of genetic resources for the UAE desert environments such as minimum etiolation in the early stages of growth would be merited further studies, which would promote stable rice cultivation in the arid conditions.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.3
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• pp.444-450
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• 2012

The physical and chemical properties of soil in the Mangyeong and Dongjin river basin had been investigated in order to establish the most optimum soil improvement plan on the reclaimed land. The total soil area by reclamation in Saemangeum basin is 113,971 ha. The classification by the distribution of soil series and soil texture is as following. 13 soil series including Chonnam, Buyong and Chonbuk series are period-unknown areas. Regarding the soil texture, they are fine silty ~ clayey very fine. From 1920s to 1960s, Mangyeong, Gwanghwal and Chonbuk series had coarse silty textured soil. After the 1970s, Mangyeong, Gwanghwal, Munpo, Yeompo, Poseung, Gapo and Hasa series have more sandy soil ~ moderately coarse loamy textured soil. Regarding the chemical properties, the concentrations of EC, Exch. $K^+$, $Mg^{2+}$, $Na^+$ and pH are high regardless of the time of reclamation. On the other hand, organic matter (OM) of top soil were 3.3~16.1 g $kg^{-1}$. The organic matter contents were very low though the soil had been farmed for a long time. Furthermore, the deep soil had almost no organic matter with 5.6~1.1 g $kg^{-1}$. The reason is believed that there had not been any movement of OM and clay because pressure or induced pans had been formed by large agricultural machineries and poor vertical drain. Regarding the forming of illuvial horizon (B layer) which tells the development extent of soil, only in the Hwapo reclaimed area where rice had been cultivated for past 90 years, Fe and Mn from top soil are deposited at underground 20~30 cm with 7~8 cm thickness by the movement of clay. It is believed that it had been possible because the earthiness is silty clay loam soil with relatively high content of clay. The soils are soil with concern of damage from sea water, soil on flimsy ground and sandy soil. Therefore, soil improvement for stable crop production can be expected; if the water table would be lowered by subsurface drainage, the water permeability would be enhanced by gypsum and organic matter, and the sandy soil would be replaced by red soil with high content of clay.

• Korean Journal of Environmental Agriculture
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• v.22 no.2
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• pp.79-86
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• 2003

This research was conducted to present reference data to be used as newly reclaimed tidal land management. We investigated vegetation succession at 4 reclaimed/reclaiming project areas and discussed relationship with soil and vegetation trhrough investigation and analysis soil chemical characteristics at 2 areas. 14 families 58 kinds were investigated. Vegetation were variou at Dea-Ho conservation polt and Seok-Mun National Industrial Area which are maintaining naturally. Vegetation were simple at Hong-Bo and Dongjin and MinKyong river areas which effected sea water. Common species that were investigated at 9 sites were Suaeda asparagoides, Aster tripolium, Phragmites australis, Suaeda maritima, Suaeda japonica, Carex scabrifolis. As soil desalinization progressing, soil classified at first saline-soidc soil, the nest saline soil and then normal soil. Chenopodiaceae revealed at about 30 dS/m of soil ECe and existed to 10 dS/m of soil ECe. At about 20 dS/m of soil ECe. Aster tripolium, Calamagrostis epigeios, and Sonchus brachyotus revealed and then non-halophytes and common plants at inland revealed at low soil ECe of about 10 dS/m. However it was not to progress vegetation sucdession and soil desalinization at the same time, owing to input of seeds or plants ect from out-ecosystem. So for promotion of vegetation at newly reclaimed tidal land, we proposed that it was very effective to plant artificially halophytes or suitable species through soil test.