Soluble salts are dominant form at reclaimed tidal saline soil, which can be improved by leaching with excessive irrigation water. The objective of this study was to evaluate the effect of irrigation on soil salinity and corn (Zea mays) growth at reclaimed tidal saline soil. A field experiment was conducted at Saemangeum reclaimed tidal land in Korea, during two successive growing seasons between 2013 and 2014. During the growing season, three different irrigation practices were applied as following; (1) irrigation at −35 kPa, (2) irrigation at −50 kPa, and (3) no-irrigation. Soil salinity was significantly decreased with increasing irrigation rates. Soluble cations were statistically decreased with irrigation; especially the depression of soluble Na was greater than other cations. Corn growth was significant with irrigation practice and the length of stem, panicle number, and stem thickness was statistically greater compared to the control. Although the germination rate was more than 95% in all treatment, withering rate was great in both growing seasons, which was significantly decreased with irrigation practice. Our results indicated that salt control is critical at reclaimed tidal saline soil and irrigation practice based on soil potential could be one of the best management options to alleviate salt damages for stable crop production at reclaimed tidal saline soil.

높은 염 농도와 알칼리성 특성으로 식생토양으로 활용에 어려움이 있는 간척지 토양을 복원하고 식생회복 을 목적으로 양송이 퇴비 와 미 발효 양송이 수확 후 배지를 새만금 간척지 토양과 천수만 간척지 토양에 복토, 혼합 한 후 각 토양의 이화학성분석과 식생회복 실험을 수행하였다. 간척지 토양의 이화학성 분석 결과, 새만금 토양은 pH 8.5, Na+ 함량은 1.4 cmol+/kg으로, 천수만 토양은 pH 7.2, Na+ 함량은 0.8 cmol+/kg의 특성을 보였다. 수확 후 배지 처리에 의한 간척지 토양의 중화 효과와 벼 재배실험을 통한 식생성장 상태를 8주 간 모니터링 하면서 토양의 미생물 생장과 이화학적 특성을 분석하였다. 무처리에 비해 처리 수확 후 배지 처 리구에서 벼의 식생피복율과 성장이 상대적으로 높게 나타났으며, 처리구의 경우 천수만 토양이 새만금 토양보다 생장효과가 다소 높았다. 또한 복토 및 식생 후 새만금 토양의 pH는 8.5에서 7.4로 중화 되었으 며, Na+ 함량도 0.9 cmol+/kg으로 감소되었으나, 천수만 토양은 pH 7.0, Na+ 함량은 0.6 cmol+/kg의 특성을 보임으 로서 수확 후 배지 처리에 의한 간척지 토양의 중화 효과와 벼 재배실험을 통한 염농도 저감 효과를 보였다.

장님마디톡토기는 토양생태계에서 오염물질의 독성영향을 평가하기 위한 국제 공인 표준시험종으로 제안되고 있다. 토양생태계 먹이사슬에서 중요한 역할을 수행하는 톡토기의 특성에 따라 다양한 연구가 시도되고 있으며, 더 민감한 독성영향 종말점이 제시되고 있는 실정이다. 본 연구에서는 대표적인 토양오염물질인 중금속의 생태독성영 향을 평가하기 위하여 장님마다톡토기의 도약능을 이용하였다. 장님마디톡토기는 표준시험법에 따라 중금속 오염토 양에 만성노출되었으며, 이후 생존개체를 수집하여 도약능 평가를 수행하였다. 톡토기의 도약은 일시적인 화학스트레 스를 이용하여 유도되었으며, 이를 회피하기 위한 운동능을 컴퓨터 프로그램을 통해 기록하여 평가하였다. 중금속 오염토양에 노출된 개체는 도약을 통한 회피 경로가 단순화되었으며, 도약 횟수와 길이가 중금속 농도에 따라 통계적으로 유의하게 감소하였다. 이는 중금속 오염토양에서 톡토기의 회피능력이 감소할 수 있음을 의미하며, 생태독성을 평가하기 위한 종말점이 될 수 있을 것이라 판단된다.

톡토기는 토양에 서식하는 절지동물로서 다양한 기후와 환경에 적응하여 생활하면서 전 세계적인 분포를 가지는 생물이다. 대부분의 톡토기 종들은 습기가 많은 표토층에 주로 서식하며 토양내의 유기물질을 섭취 및 분해하여 토양의 2차 생산 및 에너지의 유통과정의 중요한 역할을 생태계 내에서 수행하고 있다. 토양과 밀접한 연관이 있는 톡토기를 이용하여 토양의 기초생산력을 측정하고 농약 및 비료와 같은 화학물질의 환경독성을 평가하거나 토양 오염에 대한 부차적인 영향을 조사하기 위하여 토양지표생물로 톡토기를 이용하는 방안에 대해 연구하기도 하였다. 톡토기 종은 다양한 환경에서 서식하고 있어 절지동물의 환경 적응력의 생리적인 특성을 연구하는데 도움을 줄 수도 있고, 서식지의 생태적인 특징을 파악하는 지표종으로 이용도 가능 할 것이다.

The object of this study conducted to investigate the effect of paddy-upland rotation cropping system on soil properties and crop productivity in newly reclaimed tidal land. Five types of paddyupland rotation cropping system were evaluated : Rice-Rice (RR) Rice-Maize (RM), Mize-Maize (MM), Rice-Soybean (RS), Soybean-Soybean (SS). The soil bulk density was the lowest RM treatment, and soil pH was a tendency to be lower in all treatments of the paddy-upland rotation cropping system. RM treatment showed a higher moisture content and lower Electrical conductivity than RR treatment. Results of maize productivity in paddy-upland rotation cropping system, Except for the stem diameter growth, RM treatment showed good growth and productivity than MM treatment. Soybean growth and yield increased in the rotated upland cultivation from rice-paddy field compared to the SS treatment. But, overall treatments indicated poor growth and yield. In this study, we offer the effects of paddyupland rotation cropping system on the soil properties and upland crop growth and yield, and also out results can be provide supporting basic data that introduced paddy-upland rotation in reclaimed tidal land.

발전소 해체 및 핵종누출 시 원자력 관련 시설 주변의 방사성오염 토양은 주민의 거주 및 공업용지로의 재사용을 위해 토양 제염이 불가피하다. 본 논문에서는 기존 토양복원 기술을 생물학적, 물리/화학적, 열적 처리로 분류하고 각 기술의 원리 및 처리 물질을 분석 및 조사를 통해 방사성물질로 오염된 토양에 적용 가능한 기술을 선정하였다. 선정된 기술을 평가하기 위 해 경제성, 적용성, 기술성을 고려하였다. 또한 High, Medium, Low로 가중치를 적용하여 평가하였다. 이에 따른 결과값을 바탕으로 방사성물질로 오염된 토양에 가장 적합한 토양제염 방법을 제시하고자 한다.

Soil salinity is the most critical problem at reclaimed tidal saline soil in Korea. The objective of this study was carried out investigate the salt movement in upland soils at Gyehwa-do region in Saemangeum reclaimed land on the south Korea coasts. The experiment was conducted 5% sloped polt (3.0 m × 10.0 m) with 14 treatments and it were separated by low salinity division (LSD) and high salinity division (HSD) install. The cation content in ground water increased during time course, but in the case of land surface water the content was variable, and K+was lower than that of Na and Mg. At the LSD under rainproof condition, the salinity was directly proportional to soil water content, but at the HSD the tendency was no reversed. In condition of rainproof, the amount of soil salinity was higher at the HSD than at the LSD. Positive correlation was obtained between the soil water content and available phosphorous content at the rainfall division, but there was no significance at the surface soil of the rainproof division. Sodium adsorption ratio (SAR) and anion (Cl−, SO4 −) contents in soil were repressed in the order of vinyl-mulching > Rice straw-mulching > control plot. Our results indicate that soluble salt control is critical at reclaimed tidal saline soil and the results can provide some useful information for deciding management plans to reduce salt damage for stable crop production and diverse utilization or cultivation could be one of the management options to alleviate salt damages at reclaimed tidal saline soil in Korea.

This experiment was conducted to establish proper irrigation method for water spinach, subtropical vegetable in plastic film house soils to prepare to future global warming of the Korean peninsula. The evaluation of irrigation with 4 different levels as −20, −40, −50 kPa as a starting point(water potential) were compared to –33 kPa as control. All treatments were ended when water potential reached at –10 kPa respectively. The amount of irrigated water, N content, plant growth and fresh yield were investigated. As a result, water potential was correlated positively with irrigation starting point in cultivation period and irrigation times, but the amount water irrigated per time, N content of harvested plant, fresh and dry yield showed negative correlation. The contents of crude protein, P, K, Ca, Fe of harvested part were most high in –50 kPa treatment. We concluded that –50 kPa was optimal irrigation starting point for water spinach cultivation in unheating plastic film house.

Measurement of soil phosphorus(P) that affects crop growth is important in regard to determining the amount of P to be top-dressed. Although numerous methods to measure soil P are available, they mostly implemented in a lab and require considerable time for analyzing. The objective of this study was to find a rapid way for Lancaster colorimetry to analyze soil P effectively and rapidly in a field. 20 soil samples each in Jinju and Geochang, Geongnam were collected and the experiment was conducted based on Lancaster. The colorimetric process can be divided into three stages: extraction, filtration and color development. To find reduced optimum extraction time, the soils were blended with a mixer at intervals of 30sec for 30sec to 2min. Syringe filters with the sizes of 0.45, 1 and 2㎛ and a syringe compressor were used for speed up of filtration. The extracted solutions with reagents were soaked in the bath with 30, 40 or 50°C at intervals of 30sec for 30sec to 2min for optimum rapid color development. Combined Rapid Lancaster(CRL) method was performed for the soil samples using the best results from each process, which was 30sec blending using a mixer, 0.45㎛ syringe filter and absorbance measurement after 2min immersion at 50°C. As a result of the CRL method, R2 for Jinju soil and Geochang soil showed 0.791 and 0.936 respectively when compared to the standard Lancaster method. Since there was no statistically significant difference between Lancaster and the CRL, it was considered that the CRL method could be used to analyze soil P as a substitute for Lancaster. Future study will be conducted with wet field soils in various regions.

This study was conducted to establish the techniques of the continuous wheat production of high yield level and to standardize of quality uniformity. It was selected the experimental places which were Iksan of Jeonbuk, Gwangju metropolitan city and Hapcheon of Gyeongnam. Farmers of participating in the experiment were 13 persons with two types of advanced and lower levels of their techniques in wheat cultivation, and total numbers of fields were 22 fields. The common information on the field soils were silt loam and loam in soil textures, all most deep and some moderate in soil depth, imperfectly drained in drainage classes, coastal and interior plain with some alluvial fan or local valley in land topography. It was investigated in status of the physico-chemical properties of soils. Soil pH was 6.0 in mean values with 5.2 ~ 7.5 ranges, organic matter(OM) was 25 g/kg with 16 ~ 39 ranges, available P2O5 194mg/kg with 47 ~ 586 ranges, available SiO2 164mg/kg with 57 ~ 454 ranges, in exchangeable cations, K was 0.46 with 0.20 ~ 0.98, Ca was 6.2 with 3.6 ~ 11.7, Mg was 1.8 with 0.9 ~ 3.4 cmol(c)/kg in ranges, and these properties of soils were higher in advanced than those of lower level farmers. The amounts of fertilization in N-P2O5-K2O were 184-49-50 kg/ha in farmers application, 108-114-47 kg/ha in soil testing and 94-83-41kg/ha in standard recommendation. Fertilizer application amounts by farmers were higher than those of soil testing and standard recommendation by 76 ~ 90 kg/ha in N and 3 ~ 9 kg/ha in K2O, and less by 34 ~ 74 kg/ha in phosphate fertilizer.

This study was conducted to develop a handy earth auger for use in sloppy and rugged forest terrains in order to reduce labor cost which comprises a major part of the production costs in forest afforestation projects. The first prototype is developed consist of two parts, the soil-digging screw and the battery power source. The specifications of the first prototype screw are: length of 170㎜, a top diameter of 60㎜, bottom diameter of 47㎜, 23° angle for each helix, and a 50㎜ awl-head tip. The use of a single line of screw was selected for reduced weight. In addition, a power source of rotary DC Motor(WD-6G2425, WONILL, Korea) with a maximum torque of 30㎏ f-㎝, rotation of 20-30rpm, K6G30C decelerator with a reduction ratio of 30:1 which could be used with no load for 48 was operated. In consideration of its weight, a lithium battery was utilized in line with the goal of developing a lightweight auger. In order to evaluate the performance of the first prototype, test sites were selected as 6 areas. The rotational force was found to be highest in area A(Solid area), followed by areas F(Mounted slope 40° area) and E(Mounted slope 30° area). It was also observed that in general, the rotational force increased along with the increase in soil depth with the maximum rotational force recorded at 10㎝.

The purpose of the study is to analyze the physical and chemical characteristics of soils from the forest fire burned area in Gyeongju National Park. According to the physical characteristics of soils, soil temperatures and soil moistures in reforestation area (site 2 and 3) and natural restoration area (site 4 and 5) were higher than in control area (site 1). In terms of chemical characteristics, hydrogen exponents (pH) in reforestation area and natural restoration area were higher than in control area. The rates of available phosphoric acid (P2O5) in control area and reforestation area (site 1) had high rates, but rates in reforestation area (site 2) and in natural restoration area (site 5) had low rates. The rates of accumulated organic matter (O. M.) in reforestation area and natural restoration area were lower than in control area. The percentages of total nitrogen (T. N.) were analyzed similarly in all study areas and soils from reforestation area and natural restoration area had higher cation exchange capacity (CEC) than from control area. Therefore these results determines that soils from the forest fire burned area are being restored to normal gradually.