• Korean Journal of Agricultural Science
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• v.37 no.3
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• pp.435-449
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• 2010

Soils in the sloping uplands in Korea are subject to intensive land use with high input of agrochemicals and are vulnerable to soil erosion. Development of the environmentally sound land management strategy is essential for a sustainable production system in the sloping upland. This report addresses the status of upland agriculture and the best management practices for the uplands toward the sustainable agriculture. More than 60% of Korean lands are forest and only 21% are cultivating paddy and upland. Uplands are about 7% of the total lands and about 62% of the uplands are in the slopes higher than 7%. Due to the site-specificity of the upland, many managerial and environmental problems are occurring, such as severe erosion, shallow surface soils with rocky fragments, and loadings of non-point source (NPS) contaminants into the watershed. Based on the field trials, most of the sloping uplands were classified as Suitability Class III-V and the major limiting factor was slope and rock fragments. Due to this, soils were over-applied with N fertilizer, even though N rate was the recommendation. This resulted in decreases in yield, degradation of soil quality and increases in N loading to the leachate. Various case studies drew management practices toward sustainable production systems. The suggested BMP on the managerial, vegetative, and structural options were to practice buffer strips along the edges of fields and streams, winter cover crop, contour and mulching farming, detention weir, diversion drains, grassed waterway, and slope arrangement. With these options, conservation effects such as reductions in raindrop impact, flow velocity, runoff and sediment loss, and rill and gully erosion were observed. The proper management practice is a key element of the conservation of the soil and water in the sloping upland.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.7
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• pp.956-959
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• 2001

Three perennial grasses, Napier (Pennisetum purpureum), Andropogan (Andropogan gayanus) and Para (Brachiria mutica), were grown at different hill heights dividing the hill slope into three regions (top, middle and bottom). The first two grasses gave the highest biomass yields (29.9 and 37.6 tonnes/ha/harvest, respectively) followed by Para (20.5 t/ha). No significant (p>0.05) changes in biomass yields of the grasses were found due to differences in hill heights. The grasses were harvested three times in the first year of cultivation. Maize and cowpea as sole crops or their intercrops were cultivated in the plain land and the intercrop gave the highest biomass yield (46.7 t/ha, p<0.05). The biomass produced was successfully ensiled in the underground pits at the hill tops.

• Journal of the Korean Institute of Rural Architecture
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• v.14 no.1
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• pp.57-66
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• 2012

This study focuses on the applicability of hill housing design in accordance with topographic characteristics on sloping sites. The urgency for housing still exists but hill sites have to be planned by gradual development using 'all available land' within any particular community. However, there is a reaction towards being more closely involved with nature and landscape. Sloping and hill sites must be developed by intelligent and sensitive planning, integrating the existing environmental factors. The results of this study are as follows : 1. The conditions of location are regarded as the concepts of spactial configuration. It should be developed on the basis of awareness that nature and human beings exist together. 2. It is inevitable that the development of the hill housing should be performed prefer to the topographic characteristics. 3. Planning elements of ecological residental blocks which are possible for constructing on the hill site can be developed and applied, on the basis of geographical characteristics, by housing types.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.1300-1304
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• 2008

The fact that soil loss causing to increase muddy water and devastate an ecosystem has been appearing upon a hot social and environmental issues which should be solved. Soil losses are occurring in most agricultural areas with rainfall-induced runoff. It makes hydraulic structure unstable, causing environmental and economical problems because muddy water destroys ecosystem and causes intake water deterioration. One of three severe muddy water source areas in Soyanggang-dam watershed is Jawoon-ri region, located in Hongcheon county. In this area, many cash-crops are planted at illegally cultivated agricultural fields, which were virgin forest areas. The purpose of this study is to estimate soil loss with current land uses (including illegal cash-crop cultivation) and soil loss reduction with land use conversion from illegal cultivation back to forest. In this study, the Sediment Assessment Tool for Effective Erosion Control (SATEEC) ArcView GIS system was utilized to assess soil erosion. If the illegally cultivated agricultural areas are converted back to forest, it is expected to 17.42% reduction in soil loss. At the Jawoon-ri region, illegally cultivated agricultural areas located at over 30% and 15% slopes take 47.48 ha (30.83%) and 103.64 ha (67.29%) of illegally cultivated agricultural fields respectively. If all illegally cultivated agricultural fields are converted back to forest, it is expected that 17.41% of soil erosion and sediment reduction, 10.86% reduction with forest conversion from 30% sloping illegally agricultural fields, and 16.15% reduction with forest conversion from 15% sloping illegally agricultural fields. Therefore, illegally cultivated agricultural fields located at these sloping areas need to be first converted back to forest to maximize reductions in soil loss reduction and muddy water outflow from the Jawoon-ri regions.

• Magazine of the Korean Society of Agricultural Engineers
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• v.45 no.6
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• pp.83-95
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• 2003

In this study, a new concept in a paddy consolidation project is introduced in that curved parallel terracing with contour-lined layout is adopted in sloping areas instead of conventional rectangular terracing. The contoured layout reduces earth-moving considerably compared to rectangular methods in consolidation projects. The objective of the paper is to develop a combinatorial optimization model using the network theory for the design of contour-lined plots which minimizes the volume of earth moving. The results showed that as the length of short side of plot is longer or the land slope is steeper, the volume of earth moving for land leveling increases. The developed optimization model is applied for three consolidated districts and the resulting optimal earth moving is compared with the volume of earth from the conventional method. The shorter is the minimum length of short side of a polt with increases the number of plots, the less is the volume of earth. As the minimum length of short side is 20 m for efficient field works by farm machinery, the volume of earth moving of optimal plot is less by 21.0∼27.1 % than that of the conventional consolidated plots.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2004.11a
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• pp.189-194
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• 2004

Owing to the mass-housing policies of high-density and high-rise, the residential environments in Korea have come to be uniform and monotonous. Nevertheless, the design competitions introduced for the first time in 1980s have Played significant roles in developing the fresh ideas and concepts in housing design. And in our country, the land of the gradient $0-9^{\circ}$ that is able to plan as level sites come up to 32.5% of the total land and the land of the gradient $10-29^{\circ}$that should be designed by considering the characteristics of the sloping sites is 53.2% of the whole. For that reason, the development of the apartment housing in the sloping site has been done largely to solve the issues associated with the scarcity of the land. Therefore, it is very meaningful job to see the various design methods on the basis of the characteristics of the sites, particularly gradient, by analyzing the prizewinners in the design competitions. In this context, the research analyzed the works that won the design competition after 1990, and organized the types of the block plans and the design characteristics applied in our residence housing. Secondarily, it classified that types by the gradient and analyzed statistically and compared the numerical value.

• Carbon letters
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• v.26
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• pp.66-73
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• 2018

We assessed the effects of combining bio-char with straw residue mulching on the loss of soil soluble nutrients and citrus yield in sloping land. The two-year study showed that straw residue mulching (ST) and bio-char application combined with straw residue (ST+BC) can significantly reduce soil soluble nutrient loss when compared with the control treatment (CK). The comparative volume of the soil surface runoff after each of the treatments was as follows: CK > ST > ST + BC. Compared with the CK, the runoff volume of the ST was reduced by 13.6 % and 8.5 % in 2014 and 2015, respectively. Compared with the CK, combining bio-char with the ST application reduced the loss of soluble nitrogen and improved the soil total nitrogen content reaching a significant level in 2015. It dramatically increased the soil organic matter content over the two year period (36.3% in 2014, 50.6% in 2015) as well as the carbon/nitrogen ratio (C/N) (16.6% in 2014 and 39.3% in 2015). Straw mulching combined with bio-char showed a trend for increasing the citrus yield.

• Ecology and Resilient Infrastructure
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• v.4 no.3
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• pp.180-185
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• 2017

Restoration of min-impacted arable land is often performed through stabilization of trace elements by amendment treatment combined with (clean) soil covering on the surface. Recently, soil loss problem from sloping remediated agricultural lands has risen as an emerging concern. In this study, efficacy of aggregation formation was assessed by single and binary treatments of four potential amendments (bentonite, lime, organic matter, and steel slag) applied on three cover soils having different clay contents (9.4, 14.7, and 21.2% for A, B, and C soils respectively). In results of single treatments, 5% organic matter for A soil and 5% lime for B and C soils were found most effective for the aggregation formation compared to the respective controls (without amendments). Among nine binary treatments, 3% organic matter + 1% lime for A soil and 1% organic matter + 3% lime for both B and C soils led to the highest formation of aggregation (30.4, 25.0, and 36.5% for A, B, and C soils). For a site-application, the soil erodibility difference between the cover soils (0.045, 0.051, and 0.054 for A, B, and C soils, respectively) and the national average of arable land (0.032) was assumed to be compensated by amendment addition, which is equivalent to 29.1% aggregation formation. To achieve the aggregation goal, 5% lime for A and B soils and 3% lime for C soil were best in the consideration of benefit/cost, thereby effectively and economically reducing soil loss from sloping remediation site. Soil alkalinity induced by lime treatment was not considered in this work.

• Korean Journal of Soil Science and Fertilizer
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• v.7 no.3
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• pp.137-140
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• 1974

The present-state survey was carried out on reclaimed land of entire country to grasp the farming conditions, soil characteristics and productivities. The results was summarized as follows: 1) Among farmers participating in reclamation, small farmers, which hold land under cultivation less than 1 ha occupied 42 percent of total farmers; while big farmers, hold more than 3 ha, occupied only 11.1 percent. 2) The land use of reclaimed land by reclaimed year had such big variation that mulberry land was decreasing, however, grass land markedly increased. 3) Soils less than 15 percent slope in reclaimed land occupied 68.7 percent of total reclaimed land, and steep sloping land was reclaimed through bench-terraced method, while gently sloping land, through non terraced one. 4) The chemical properties of reclaimed land was very poor, except for phosphate, all element after 10 years of reclamation was under levels of land of cultivation. 5) Amount of fertilizer application to reclaimed land was under that of recommendation. 6) The yield of reclaimed land was 30 to 86 percent of average of land under cultivation.

• Korean Journal of Soil Science and Fertilizer
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• v.11 no.4
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• pp.271-281
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• 1979

The neccessity of hillside land reclamation for food production in Korea is no matter of question. Accordingly, the Government has launched some large scale hillside land reclamation projects. From the past experiences followings are pointed out as to the rational hillside land reclamation engineering methodologies. 1. It is observed that due to the shortages in labor and high wage, the machanization in hillside land reclamation will be an urgent subject. 2. There are several engineering methods for the reclamation of hillside lands; contour terracing, improved contour terracing, bench terracing and sloping bench terracing. 3. Selection of suitable methods will demand the considerations on the topography, particularly degree of slope, and the land use after reclamation. For ordinary crops cultivation, slope should be low and contour terracing is to be recommended, to enable the introduction of machines. In case of grass land development, after smoothing the land surface, improved contour terracing might be selected. And for the orchard development, sloping bench terracing with the construction of roads between the terrace will be suitable.