• Korean Journal of Soil Science and Fertilizer
• /
• v.42 no.3
• /
• pp.179-186
• /
• 2009

Relation between soil salinity and forage yield of five upland crops such as sudan grass, sesbania, barnyard grass, corn and soybean was studied in the three reclaimed lands of Korea during two years from 2007 to 2008. Although plant number emerged was obtained satisfactory by desalting treatment, further growth of crops was sharply affected by re-salting process according to soil drying. Soil salinity varied place by place and changed constantly, crop growth was differently responded to soil salinity according to the specific conditions of the reclaimed lands. In the Iweon reclaimed land with higher soil water conductivity and sandy soil texture, crop growth and yield sharply decrease with increase of soil salinity. Relation between soil salinity and crop growth and yield was well expressed as logarithmic function. Surface soil EC to reach at 50% of growth reduction to the tallest height of crops was $5dS\;m^{-1}$ for soybean, $6dS\;m^{-1}$ for corn and $7dS\;m^{-1}$ for sudan grass, sesbania, and barnyard grass by logarithmic function. In the Hwaong and Yeongsangang reclaimed lands with low soil conductivity and finer soil texture, plant growth response to salt stress was statistically vague by mixing of harmful influence from flooding and wet injury. However, it is observed that crop growth and yield on the place of lower salinity was better than crop growth on the place of higher salinity. It is accordingly concluded that flooding control during summer rainy season is vary important as well as desalting process for good growth of soiling and forage crops in the newly reclaimed land from tidal flat.

• Korean Journal of Soil Science and Fertilizer
• /
• v.44 no.5
• /
• pp.859-865
• /
• 2011

This study looked into 110 sites of orchard fields to investigate the relationships between the physical and chemical properties of soils, including heavy metal contents, and the topographic characteristics of the fields in Jeonbuk province. The topographic distribution of orchard fields in Jeonbuk province was local valley and fans, hilly and mountains, mountain foot slopes, alluvial plains, diluvium, and fluvio-marine deposits. Forty-six percent (46%) of total orchard fields were located in the hilly and mountains. Soil texture of the local valley and fans was mostly sandy clay loam, and the soil texture of other topographical sites were varied. Bulk density, porosity, and soil hardness were not different among the various topographic sites. The content of plant available water was the highest (19.5%) in the sites of diluvium. Soil pH, electrical conductivity (EC), and exchangeable $Mg^{2+}$ content were the highest in the sites of fluvio-marine deposits, whereas the contents of soil organic matter (SOM), available phosphorus, and exchangeable $Ca^{2+}$, $K^+$, and $Na^+$ were not significantly different among the topographic sites. Also, soil pH and SOM content were generally in optimal ranges for the fruit plants in the orchard fields, but other values were mostly higher than those in optimum. In addition, the contents of heavy metals were much lower than the levels of Soil Contamination Warning Standard.

• Korean journal of applied entomology
• /
• v.58 no.1
• /
• pp.37-47
• /
• 2019

A survey on the geographical distribution of two soybean cyst nematodes, Heterodera glycines and Heterodera sojae, was conducted in soybean cultivation areas in the Gangwon-do and Chungcheongbuk-do provinces. In 67 fields of 10 counties or cities in Gangwon-do province, H. glycines was detected in 13 fields, H. sojae was detected in five fields, and both species were found in two fields. In 84 fields of nine counties or cities in Chungcheongbuk-do province, H. glycines was detected in 27 fields, H. sojae was detected in four fields, and both species were found in five fields. The diversity and dominance of the plant parasitic nematodes in the Gangwon and Chungbuk provinces were not significantly different among the soybean cultivars. The diversity and dominance index of the plant parasitic nematodes according to the presence or absence of soybean cyst nematodes did not show any significant difference between the soybean cultivation areas of both provinces. The relationship between the soybean cyst nematodes and soil chemical properties showed a low coefficient of determination, and the density of soybean cyst nematodes tended to increase as the pH and available phosphate content in soil samples increased. The soil texture of cyst nematode-detected fields was mostly sandy soils, which amounted to about 60% of the total. As the clay and silt content increased, the density of soybean cyst nematodes tended to decrease, and as the sand content increased, the density of cyst nematodes tended to increase.

• Asian Journal of Atmospheric Environment
• /
• v.6 no.2
• /
• pp.118-126
• /
• 2012

To investigate the effect of aircraft traffic emissions on soil pollution, metal levels were analyzed for 8 metals (Fe, Cr, Pb, Zn, Cu, Ni, Mn and Cd) from the vicinity of the Indira Gandhi International (IGI) airport in Delhi, India. The texture of the airport soil was observed to be sandy. Among the metals, Cd showed minimum concentration ($2.07{\mu}g\;g^{-1}$), while Fe showed maximum concentration ($4379{\mu}g\;g^{-1}$). The highest metal accumulation was observed at the landing site. Significant correlations were observed between metals and different textures (sand, silt, and clay) as well as with organic carbon (OC). The results indicate that grain size play a major role in OC retention in soil and subsequently helps in adsorption of metals in soil. M$\ddot{u}$ller's geoaccumulation index (I-geo) showed that airport soil was contaminated due to Cd and Pb with the pollution class 2 and 1, respectively. Pollution load index of the airport site was 1.34-3 times higher than the background site. The results of factor analysis suggested that source of the soil metal is mainly from natural weathering of soil, aircraft exhaust, and automobile exhaust from near by area. With respect to Dutch target values, the airport soils showed ~3 times higher Cd concentration. The study highlighted the future risk of enhanced metal pollution with respect to Cd and Pb due to aircraft trafficking.

• Korean Journal of Plant Resources
• /
• v.25 no.6
• /
• pp.719-730
• /
• 2012

This study was conducted to investigate the environmental characteristics of natural habitats, and the genetic variations in samples from 19 different quadrates of Asplenium scolopendrium 10 habitats. The natural habitats of A. scolopendrium were located at an altitudes 110-973 m with inclinations of $7-30^{\circ}$. All the quadrates were located on north facing slopes. The average field capacity of the soil is 31.4%, with organic matter at 16.7%, and the pH is 5.84. The soil texture was confirmed as sandy loam in 8 habitats and silt loam in 2 habitats. A total of 214 vascular plants were identified from 10 habitats. The importance value of the herbaceous layer (H) was the highest in A. scolopendrium, at 10.4%, followed by Arachniodes standishii (7.3%), Dryopteris crassirhizoma (6.5%), and Polystichum tripteron (5.3%), which implies that the natural habitats of A. scolopendrium are affinity with ferns. The species diversity of A. scolopendrium was estimated as on average 1.09, while the dominance and evenness were 0.12 and 0.87, respectively. The result of the RAPD analysis, among 59 bands amplified with a primer, 25 (42.4%) showed polymorphism. Twenty-one individuals of 10 habitats could be classified into four groups with similarity coefficient values ranging from 0.74 to 1.0. Mt. Mullae and Geumdaebong populations shows basal branching within the 21 individuals. Ulleung-do island and Jeju-do island population forms an independent clade, respectively. Mt. Moak and Byeonsan-bando clade formed a sister to the Ulleung-do island and Jeju-do island clade.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 2002.04a
• /
• pp.66-69
• /
• 2002

In this work, cost effective venting is considered by comparing flow rates of 5$m\ell$/min, 10$m\ell$/min, and 20$m\ell$/min. Studies were performed on a soil artificially contaminated with diesel oil (the initial TPH(Total Petroleum Hydrocarbon) concentration of 7098mg/kg), and nutrient condition was C:N:P rate of 100:10:1. The soil has a sandy texture with pH of 6.8, 2.16 ~2.38% organic matter, a total porosity of 47~52% and field capacity 16.2~ 17.2%. The column experiments was made of glass column of 60cm length and 10cm I.D. at controlled temperature of 2$0^{\circ}C$($\pm$2.5$^{\circ}C$). The efficiency of continuous flow rate of 5, 10 and 20$m\ell$/min resulted in separately 61.3%, 58.1%, and 55% reduction of initial TPH concentration(7098mg/kg). Hydrocarbon utilizing microbial count and dehydrogenase activity in air flow of 5$m\ell$/min were higher than those of the others. The first order degradation rate of n-alkanes ranging from C10 to C28 was higher than that of pristane and phytane as isoprenoids. The $C_{17}$/pristane and $C_{18}$phytane ratios for monitoring the degree of biodegradation were useful only during the early stages of oil degradation. Degradation contributed from about 89% to 93% of TPH removal. Volatilization loss of diesel oil in contaminated soil was about 7% to 11%, which was significantly small compared to degradation.n.

• Korean Journal of Soil Science and Fertilizer
• /
• v.51 no.1
• /
• pp.50-60
• /
• 2018

This study was to evaluate the effect of organic amendments incorporation on soil properties and plant growth under two different soil salinity levels and various cultivated crops at Saemangeum reclaimed tidal land for three years from 2012 to 2014. The soil texture of the experimental site was sandy loam. Four different crops, sesbania (Sesbania grandiflora), sorghum-sudangrass hybrid (Sorghum bicolor-Sorghum sudanense), rice (Oryza sativa L.) and barley (Hordeum vulgare) were cultivated at low (< $1dS\;m^{-1}$) and high (> $4dS\;m^{-1}$) soil salinity levels. The soil salinity was significantly lowered at the rice cultivation site compared to continuous upland crops cultivation site in high soil salinity level. But the soil salinity was increased as cultivating sesbania coutinuously in low soil salinity level. The soil organic matter content was increased with the incorporation of straw at the continuous site of rice and barley, and the average of soil organic matter was increased by $0.9g\;kg^{-1}$ per year which was effective in soil aggregate formation. The highest biomass yield plot was found in barley (high salinity level) and sesbania (low salinity level) cultivation site, respectively. Our research indicates that rice cultivation in paddy field with high salinity level was effective in lowering soil salinity and sesbania cultivation was useful to biomass production at upland with low salinity. In conclusion, soil salinity and organic matter content should be considered for multiple land use in newly reclaimed tidal land.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.9 no.2
• /
• pp.16-22
• /
• 2006

This study was carried out to estimate the physical and chemical soil characteristics in highway cutting slope areas. The soil was sampled in cutting area and natural vegetation area that was located in the upper areas of the highway cutting slope. The average total soil depth, bulk density, and soil hardness were bad in the highway cutting slope sites. The sandy loam was the most soil texture in the study area. The concentration of soil organic matter and nitrogen were very low in all highway cutting areas. The concentration of exchangeable cations was similar between the highway cutting slope and the natural vegetation sites in each highway. The soil pH was higher in highway cutting slope areas than in natural vegetation sites. In conclusion, chemical and physical properties of soil were bad in the cutting slope than in the natural vegetation area because of the loss of soil by cutting of slope area and less organic matter input by less vegetation in the highway cutting slope area. We should employ possible method to reduce the loss of soil, and compost and fertilization treatment could help to increase soil nutrient content in the cutting slope area.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.9 no.6
• /
• pp.86-94
• /
• 2006

This study was to analyze vegetation and soil characteristic, and ordination of Bupleurum euphorbioides community located in Mt. Seorak area, Mt. Sobaek area, and Mt. South Deogyu area. Bupleurum euphorbioides community was classified into Carex lanceolata subcommunity and Chrysanthemum zawadskii var. alpinum subcommunity, and Chrysanthemum zawadskii var. alpinum subcommunity was classified into Calamagrostis arundinacea and Carex breviculmis group. In the study sites, soil organic matter, nitrogen, available phosphorous, changeable potassium, changeable calcium, changeable magnesium concentration, cation exchange capacity, and soil pH were ranged from 9.0~15.2%, 0.32~0.47%, 3.0~8.6ppm, 0.3~0.9me/100g, 0.5~1.5me/100g, 0.2~0.6me/100g, 11.4~16.1me/100g, and 4.3~4.6, respectively. And, soil texture was sandy loam or loam. The Carex breviculmis group of Chrysanthemum zawadskii var. alpinum subcommunity was found in area of high elevation and had high exchangeable K, Ca, and Mg concentration. The Calamagrostis arundinacea group of Chrysanthemum zawadskii var.alpinum subcommunity was found in area of low elevation and had lower exchangeable K, Ca, and Mg concentration than in the other subcommunity. The Carex lanceolata subcommunity was found in area of medium elevation and had medium exchangeable K, Ca, and Mg concentration. The Carex lanceolata subcommunity was located in a path of top the mountain peak, and has been destroyed. We need any action to protect the subcommunity.

• Journal of the Korean association of regional geographers
• /
• v.12 no.6
• /
• pp.631-644
• /
• 2006

The study area is a pocket beach which consisted of sandy beach, dune, agricultural land and residential area etc. The coastal dune area is classified to foredune, dune plain, secondary (or back) dune. The foredune area is covered by herbaceous dune plants(ex. Carex kobomugi, Wedelia prostrata, etc.), whereas the dune plain area is covered by herbs and shrubs(Vitex rotundifolia). The most inner area, secondary dune, is planted by pine forest(Pinus thunbergii). The mean size of the beach and dune sediments ranges from 1.1 to $1.8{\Phi}$, which mean these values are higher than normal sediments. Sorting and Skewness is $0.6{\sim}-1.2{\Phi}$ and $-2.7{\sim}1.6{\Phi}$ respectively. We found that the soil formation process in the secondary dune area has been progressed rapidly from the analysis of fine grain content, organic matter content, and CEC.