• Asian Journal of Turfgrass Science
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• v.16 no.1
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• pp.19-30
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• 2002

This study was conducted to investigated the effects of rubber chips from used tires on sports turf ground as soil conditioner to improve soil physical properties. The release of heavy metal ions was detected to check the soil contamination by incorporation of recycled rubber chips with topsoil. The effects of the chips were also evaluated as topdressing material to improve surface resilience. The rate of rubber chips showed a positive relationship with soil temperature increasement. Incorporation of rubber chips increased soil temperature on surface at 2.5 cm-depth. The rates of rubber chip showed a negative relationship with ground cover rate of turfgrass in early growth season. However, after 20 weeks, treatment of 10% rubber chips at 2.5 cm-depth showed a prominent cover rate of 70% which was not significantly different with untreated control. Incorporation of rubber chips within topsoil seemed to reduce soil compaction, but the effects was not prominent on physical properties. Rubber chips did not affect chemical properties and heavy metal contamination to soil environment. Rubber chips improved resilience of the compacted ground surface as topdressing material, this effect was prominent when aerification practise was preceded.

• Journal of Microbiology and Biotechnology
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• v.25 no.4
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• pp.423-430
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• 2015

Aerobic CH₄ oxidation is an important CH₄ sink in landfills. To investigate the distribution and community diversity of methanotrophs and link with soil characteristics and operational parameters (e.g., concentrations of O₂, CH₄), cover soil samples were collected at different locations and depths from the Mengzi semi-aerobic landfill (SAL) in Yunnan Province of southern China. Specific PCR followed by denaturing gradient gel electrophoresis and realtime PCR were used to examine methanotrophs in the landfill cover soils. The results showed that different locations did harbor distinct methanotroph communities. Methanotrophs were more abundant in areas near the venting pipes because of the higher O₂ concentrations. The depth of 20-25 cm, where the ratio of the CH₄ to O₂ was within the range from 1.3 to 8.6, was more conducive to the growth of CH₄-oxidizing bacteria. Type II methanotrophs dominated in all samples compared with Type I methanotrophs, as evidenced by the high ratio of Type II to Type I methanotrophic copy numbers (from 1.76 to 11.60). The total copy numbers of methanotrophs detected were similar to other ecosystems, although the CH₄ concentration was much higher in SAL cover soil. Methylobacter and Methylocystis were the most abundant Type I and Type II methanotrophs genera, respectively, in the Mengzi SAL. The results suggested that SALs could provide a special environment with both high concentrations of CH₄ and O₂ for methanotrophs, especially around the vertical venting pipes.

• Korean Journal of Organic Agriculture
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• v.22 no.3
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• pp.413-421
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• 2014

This study was conducted into the effects of cover crops among the hairy vetch, red clover, rye, and hairy vetch+rye on the soil chemical and physical properties, and fruit yield in mature 'Fuyu' persimmon (Diospyros${\times}$kaki Thunb.) trees. The shallow-rooted red clover had poor dry matter production, resulting in the lowest coverage (66%) on the orchard floor. In contrast, the highest dry matter production observed in rye and hairy vetch+rye. Estimated N, P and K production from the cover crops were the highest on the hairy vetch+rye plots, increasing soil chemicals at a depth of 0-30 cm soil. Rye or hairy vetch+rye treatments decreased the soil bulk density and solid phase. As the hairy vetch+rye treatment increased fruit yield and sugar contents, it could be proposed as an suitable cover crop for improving productivity of persimmon trees.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.2
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• pp.131-135
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• 2007

This study was performed as an effort to reduce soil loss by investigating the phase of water flow according to soil texture and rainfall pattern and by determining the canopy cover subfactor in the RUSLE (revised universal soil loss equation). Red pepper was planted at the 15% sloped lysimeter of $2m{\times}5m{\times}0.5m$ ($width{\times}length{\times}depth$) with three different textured soils (loam, clay loam and sandy loam) and the relationship between amount and intensity of rainfall; soil loss and the amount of runoff; and amount of rainfall and runoff at different soil texture were measured at the experiment station of the National Institute of Agricultural Science and Technology (NIAST) during May to October of 2005. The amount of runoff increased with increasing amount of rainfall, showing difference in the relative increase rate of runoff at different soil texture. The increase rate of runoff with unit increase of rainfall for the lysimeter with red pepper was 0.44, 0.41 and 0.13 for loam, clayey loam and sandy loam, respectively. The minimum amount of rainfall for runoff was 23.53 mm for sandy loam, 10.35 mm for loam and 5.46 mm for clayey loam, respectively. The canopy cover subfactors of red pepper were 0.425, 0.459, and 0.478 for sandy loam, loam and clayey loam, respectively.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.2
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• pp.457-467
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• 2014

This study is to evaluate the snowmelt impact on dam inflow for the Chungju Dam watershed $6,642.0km^2$ using Terra MODIS (Moderate-Resolution Imaging Spectroradiometer) and Soil and Water Assessment Tool (SWAT). To determine the SWAT snowmelt parameter; snow cover depletion curve (SCDC) the snow depth distribution (SDD) using Terra MODIS was used, the snow depth was spatially interpolated using snowfall data of ground meteorological stations. For 10 sets (2000-2010) data during snowmelt period (November-April), the sno50cov parameter, that is, the 50% coverage at a fraction of SCDC which determines the shape of snow depletion process, showed the values of 0.4 to 0.7. The SWAT model was calibrated with average $R^2$ of 0.54 using the sno50cov of each year. The 10 years average streamflow during snowmelt period was 104.3 mm which covers 12.0% of the annual streamflow.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.3
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• pp.375-379
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• 2011

This study was conducted to evaluate the effect of rice cover crop cropping systems on rice root growth in a rice field as affected by conventional tillage without rice straw or green manure crop treatment (CTFS, check plot), no-tillage without cover crops (NTNT), no-tillage amended with rape (NTRA), no-tillage amended with rye (NTRY), no-tillage amended with hairyvetch (NTHV), and no-tillage amended with Chinese milk vetch (NTCM). In 0-5 cm soil depth, dry weight of root in NTRS ($128g\;m^{-2}$) was significantly higher than in the other plots (p<0.05) at harvesting stage. In addition, content of active organic matter at 0-5 cm soil depth was $1,684g\;m^{-2}$ in NTCM, $1,309g\;m^{-2}$ in NTRA, $1,295g\;m^{-2}$ in NTRS, $1,072g\;m^{-2}$ in NTRY, $917g\;m^{-2}$ in NTHV, $434g\;m^{-2}$ CTFS, and $426g\;m^{-2}$ in NTNT treatment. In no-tillage rice cover crop cropping system, our findings suggest that NTRS and NTCM should be enhanced root growth and active organic matter in paddy field.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.16 no.1
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• pp.99-107
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• 2013

This study was conducted to evaluate the effect of soil covering depth and vegetation base materials on the competition between Pinus densiflora Siebold & Zucc. and Lespedeza cyrtobotrya Miq., which were grown in an abandoned coal mine land for three years after seeding, by comparing their growth and stem density. The study site was consisted of sub-plots with four different soil covering depths (0cm, 10cm, 20cm, and 30cm) and four different compounds of vegetation base materials (peat moss (control), soil conditioner+peat moss (S+P), erosion control material+peat moss (E+P), and soil conditioner+erosion control material+peat moss (S+E+P)). Results of this study showed opposite pattern between P. densiflora and L. cyrtobotrya with different soil covering depth and compounds of vegetation base materials in general. P. densiflora showed the highest growth and stem density in plots with 10cm and 0cm depths of soil covering, respectively, while the lowest was shown in plots with 20cm depth of soil covering. In contrast, L. cyrtobotrya showed the highest growth and stem density in plots with 20cm depth of soil covering, while the lowest was shown in plots with 0cm depth of soil covering. In case of vegetation base materials, P. densiflora showed the highest growth and stem density in control plots and plots treated with S+P, respectively, while the lowest was shown in plots with S+E+P treatment. On the other hand, L. cyrtobotrya showed the highest growth and stem density in plots treated with S+E+P, while the lowest was shown in control plots. These results suggested the competition between two plants as a major cause of opposite patterns, which is induced by the suppressed growth and stem density of P. densiflora by fast growing L. cyrtobotrya. Despite the suppression of L. cyrtobotrya on P. densiflora, L. cyrtobotrya can play a positive role in improving soil quality, and thus it would be more desirable for restoring abandoned coal mine land to manage the growth of L. cyrtobotrya periodically, rather than eliminate them.

• Spatial Information Research
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• v.10 no.4
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• pp.533-550
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• 2002

Soil organic matter (SOM) content and other physical soil properties were extracted from a digital soil database, the Soil Survey Geographic (SSURGO) database, to map the amount of SOM and determine its relationship with topographic positions in floodplain areas along a river basin in Douglas County, Kansas. In the floodplains, results showed that slope and SOM content had a significant negative relationship. Soils near river channels were deep and nearly level, and they had the greatest SOM content in the floodplain areas. For the whole county, SOM content was influenced primarily by soil depth and percent SOM by weight. Among different slope areas, soils on mid-range slopes (10-15%) and ridgetops had the highest SOM content because they had relatively high percent SOM content by weight and very deep soils, respectively. SOM content was also significantly variable among different land cover types. Forest/woodland had significantly higher SOM content than others, followed by cropland, grassland, and urban areas.

• Korean Journal of Hydrosciences
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• v.4
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• pp.21-32
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• 1993

The estimates of both runoff depth and peak runoff by the basin runoff curve numbers, which are CN-II for antecedent moisture condition- II and CN -III for antecedent moisture condition-III, obtained from hydrological soil-cover complexes of 26 watersheds are investigated by making use of the observed curve numbers, which are median curve number and optimum curve number, computed from 250 rainfall-runoff records. For gaged basins the median curve numbers are recommended for the estimation of both runoff depth and peak runoff. For ungaged basin, found is that for the estimate of runoff depth CN-II is adequate and for peak runoff CN-II is suitable. Also investigated is the variation of the runoff curves during storms. By the variable runoff curve numbers, the prediction of runoff depth and peak runoff can be improved slightly.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.19-28
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• 2005

Passive microwave remote sensing technique have shown great potential for mon monitoring regional/global surface soil moisture. Given a single measurement at dual polarization/single frequency/single view angle, a strategic approach to artificially generating multiple microwave brightness temperatures is presented. And then the statistically generated microwave brightness temperature data are applied to the inverse algorithm, which mainly relies on a physically based microwave emission model and an advanced single-criterion multi-parameter optimization technique, to simultaneously retrieve soil moisture and vegetation characteristics. . The procedure is tested with dual polarized Tropical Rainfall Measurement Mission Microwave Imager (TRMM/TMI) over two different cover sites in Oklahoma and Beltsville field experimental data. The retrieval results are analyzed and show excellent performance.