• 한국지반공학회논문집
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• 제40권1호
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• pp.39-46
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• 2024

전 지구적 기후변화에 따른 용수확보 방안으로 인공함양 기법이 활용되고 있다. 함양률을 감소시키는 클로깅 문제는 인공함양 기법의 활용에 큰 장애가 되고 있다. 이 연구는 하천수 주입 과정에서 발생할 가능성이 있는 클로깅 평가를 위한 기초자료를 확보하기 위해 인공함양 예정 지역 충적층의 토양 조직과 광물 특성을 분석하였다. 충적층 쇄설성 입자의 주요 구성 광물은 석영, 정장석, 사장석, 흑운모 등이며, 공극을 충진하는 주요 2차 광물은 일라이트, 카오린나이트, Fe-산화광물이다. 2차 광물로서 탄산염 혹은 황산염 광물의 산출이 없는 것은 인공함양 실험 전인 연구 지역 충적층에서는 지하수와 지표수 간의 반응에 의한 화학적 클로깅은 발생하지 않았음을 시사한다. 인공함양 실험과 관련된 화학적 클로깅에 대한 평가를 위해 대수층 내 공극에서 2차 광물의 생성과 성장과 같은 충적층의 토양특성에 대한 모니터링이 필요하다.

• 한국환경복원기술학회지
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• 제11권3호
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• pp.1-11
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• 2008

Although landslides were frequently occurred under Tripterygium regelii and Rubus sp. vegetations, the damage of landslide was not observed in sasa (Sasa borealis) stands. These phenomena may be affected by forest vegetation types. This result suggested that the landslide occurred in Jirisan (Mt.) National Park may be closely related to water retention capacity at Sasa borealis stands. This study compared and analyzed the water retention capacity of each soil horizon of sasa, larch (Larix leptolepis) and mongolian oak (Quercus mongorica) stands. Soil bulk density in A horizon was lower in sasa (0.776g/$cm^3$) than in mongolian oak (0.828g/$cm^3$) and in larch stands (1.282g/$cm^3$). Water permeability in A horizon was 0.02055cm/sec for sasa, 0.00575cm/sec for mongolian oak, and 0.0007cm/sec for larch stands, respectively. The water permeability of sasa stand was about 3.6 times and about 29 times higher than in mongolian oak and in larch stands, respectively. This result indicates that water infiltration of soil surface during a rain event is more rapid in sasa than in other two stands. Soil organic matter content in B horizon was lower in larch (0.7%) than in mongolian oak (6.5%) and in Sasa (3.3%) stands. The solid ratio in A horizon was highest in larch among three stands, but that of mongolian oak and larch stands showed a similar rate. Pore space rates was 70.7% for A horizon and 70.6% for B horizon of sasa, 68.9% for A horizon and 70.6% for B horizon of sasa, 68.9% for A horizon and 70.6% for B horizon of mongolian oak forests and 51.7% for A horizon and 49.2% for B horizon of larch forests, respectively. According to pore space rates, the water retention capacity may be poor in larch stand compared with other two stands. Soil strength in sasa and mongolian stands was over 25kgf/$cm^2$ from 40cm depth, while the strength was over 25kgf/$cm^2$ from 25cm depth in larch stand. The result indicates that tree growth and water permeability in larch stand could be limited due to high soil strength. Larch stand was poor for soil pore space development to be offered to the water retention capacity, but water retention capacity of A horizon soil in sasa stand was high than that of other two stands. Therefore, establishment of sasa stand under larch stand could help to prevent landslides.

• 아시안잔디학회지
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• 제7권1호
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• pp.13-18
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• 1993

Much attention has been given recently to solve the environmental contamination in golf courses Changing to culture practice rather than chemical practice that depends on pesticides and fertilizers is a hot issue in golf courses or grasslands. Organic soil conditioners improve soil-plant envirormental conditions rich in physical properties. In this study, measuring systems to evaluate soil conditioning effects were set up for on-site purpose. After establishing the methodology for evaluating soil conditioner effects, 2 kinds of organic conditioners were rested for examination. The systems for the methodology included a set of simulating equipment for field capacity, an impact type soil column compactor, and an infiltration-percolation system. Test results using the systems showed bulk density and infiltration rate of mixed soil were decreased at highter rates of conditioner, but total porocities were increased. Increased porocities were most capillary pore space which has a positive effect on soil water potential. The systems and methodology in this study seem to have an efficiency to measure the effects of soil conditioner on site purpose.

• 한국산림과학회지
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• 제102권2호
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• pp.255-263
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• 2013

이 연구는 지리산 지역 둘레길의 토양물리성 및 화학성 변화를 분석하여 둘레길 노면토양의 피해 저감 및 관리를 위한 기초적인 자료를 마련하기 위하여 수행하였다. 지리산 둘레길과 주변 산림지역의 평균적인 토양의 특성을 분석한 결과 둘레길 노면의 토양은 사양토이었으며, 산림지역의 토성은 양토로 분석되었다. 토양용적밀도의 값은 산림지역 1.00 g/$cm^3$과 둘레길 노면 토양 1.15 g/$cm^3$로 산림지역과 둘레길 노면 토양 사이의 토양용적밀도는 유의적인 차이가 있는 것으로(P<0.05) 나타났다. 산림지역과 둘레길 노면토양의 평균토양공극률을 비교한 결과 산림지역의 평균토양공극률은 62.4%로 둘레길 노면 토양의 평균토양공극률 56.6%에 비해 산림지역의 평균토양공극률이 5.8% 높은 값을 나타내었다. 토양 내 수분함유율의 경우 산림지역에서 11.3%, 둘레길 노면 토양에서 13.3%로 둘레길 노면토양의 평균토양수분함유율이 약 2.0% 높게 나타났으며, 두 지역 간 유의적 차이는 없는 것으로(P>0.05) 나타났다. 인위적 답압에 의한 영향이 높은 토양깊이 5 cm에서의 토양경도는 조사구간의 10 cm에서보다 높게 나타나 이용자의 답압에 의한 둘레길길 영향은 현재까지 토양 5 cm 정도까지 미치는 것으로 분석되었다. 또한 토양깊이 30cm 이상에서 토양경도는 산림지역과 둘레길의 차이가 없는 것으로 나타났다. 둘레길 노면토양의 화학성을 분석한 결과, 유기물, 전질소, 유효인산, 치환성양이온($K^+$, $Na^+$, $Ca^{2+}$, $Mg^{2+}$) 모두 적정함량에 부족한 값을 나타내었는데, 이는 둘레길의 이용객의 증가에 따른 토양침식 등으로 인한 것으로 사료되며, 이를 억지하기 위해서는 이용자의 과도한 집중화 및 분산을 유도할 수 있는 방법을 강구할 필요가 있다고 사료된다.

• 한국환경복원기술학회지
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• 제13권5호
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• pp.172-179
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• 2010

This study was conducted to establish a management plan for the Songrim woodland restoration by analyzing the site characteristics of the Songrim Woodland Natural Monument (Natural Monument 445) in Hadong-Gun, Gyeongsangnam-Do, Korea. The Songrim woodland was a pure pine forest. To stimulate the growth of sub-trees or mid- story vegetation in both a non-rest year forest and a rest year forest, it is recommended to take a silvicultural practices such as pruning because canopy of over-story trees was closely covered. The Songrim woodland in the non-rest year forest severely competed among individual trees of DBH classes of 60 cm and height of 18 m, while the woodland in the rest-year forest competed with DBH classes of 62 cm and height of 10 m, respectively. Soil physical property such as soil hardness, soil pore space rates, and pF 2.7 was restored following the rest-year forest designation. Mean salt concentration in the Songrim woodland soils was 0.006%. The result suggests that it is needed to take a study to prevent the salt inputs to conserve the Songrim woodland.

• The Korean Journal of Ecology
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• 제28권4호
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• pp.181-188
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• 2005

Methods used to study carbon sequestration by soil aggregates have often excluded the concentric spatial variability and other dynamic processes that contribute to resource accessibility and solute transport within aggregates. We investigated the spatial gradients of carbon (C) and nitrogen (N) from the exterior to interior layers within macroaggregates, $6.3\sim9.5$ mm, sampled from conventional tillage (CT) and no tillage (NT) sites of a Hoytville silt clay loam. Spatial gradients in C accumulation within macroaggregates were related to the differences in C dynamics by determining the sizes and the turnover rates of fast C and slow C pools in the concentric layers of aggregates. Aggregate exteriors contained more labile C and were characterized by greater C mineralization rates than their interiors in both management systems. In contrast, C in the interior layers of aggregates was more resistant in both systems. These results indicated the spatial differentiation of C dynamics within macroaggregates, i.e., exterior layers as a reactive site and interior layers as a protective site. Greater total C distribution in the exterior layers of NT aggregates indicated more influx of C from the macropores in interaggregate space than C. mineralization (net gain of C), whereas lower C distribution within the exterior layers of CT aggregates indicated net loss of C by greater C mineralization than C influx. We found total C increased approximately 1.6-fold by the conversion of CT soils to NT management systems for a period of 36 years. Differences in total accumulation and the spatial distribution of C within aggregates affected by management were attributed to the differences in aggregate stability and pore networks controlling the spatial heterogeneities of resource availability and microbial activity within aggregates.

• Carbon letters
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• 제8권4호
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• pp.274-279
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• 2007

In order to understand the breakthrough behaviour of iodine vapours on impregnated carbon systems, an active carbon, 80 CTC grade, $12{\times}30$ BSS particle size and $1104\;m^2/g$ surface area, was impregnated with metal salts such Cu, Cr, Ag, Mo and Zn, and an organic compound Triethylene diamine (TEDA) to prepare different carbon systems such as whetlerite, whetlerite/TEDA, whetlerite/KI/KOH and ASZMT. The prepared adsorbents along with active carbon were characterized for surface area and pore volume by $N_2$ adsorption at liquid nitrogen temperature. These carbon systems were compared for their CT (concentration X time) values at 12.73 to 53.05 cm/sec space velocities and 2 to 5 cm carbon column bed heights. The carbon column of 5.0 cm bed height and 1.0 cm diameter was found to be providing protection against iodine vapours up to 5.5 h at 3.712 mg/L iodine vapour concentration and 12.73 cm/sec space velocity. The study clearly indicated the adsorption capacities of carbon systems to be directly proportional to their surface area values. Dead layer with all the prepared carbon systems was found to be less than 2.0 cm indicating it to be minimum bed height to have protection against $I_2$ vapours. Effect of carbon bed height and flow rate was also studied. The active carbon showed maximum protection at all bed heights and flow rates in comparison to all other impregnated carbon systems, showing that only physical adsorption is responsible for the removal of iodine vapours.

• 아시안잔디학회지
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• 제25권1호
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• pp.69-72
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• 2011

토양입단화는 토양의 물리적 화학적 그리고 생물학적인 변화를 일으키는 활발한 과정이다. 토양입단화를 통해서 생성된 토양공극은 토양에서 공기와 물의 순환을 증가시키는 역할을 하게 된다. 유기중합물이 토양입단 안정화에 대한 긍정적인 역할은 많은 연구결과에서 보고가 된 바 있다. 본 실험의 목적은 유기중합물이 토양입단화와 페레니얼 라이그래스의 성장에 미치는 영향에 대해서 알아보기 위해서 수행되었다. 유기중합물의 세가지 농도가 적용이 되었으며 실험을 위해 두가지 토양이 사용이 되었다. 첫번째 토양으로 4.0%의 유기물이 함유된 양토가 건조된 후 사용이 되었으며 두번째 토양으로 점토가 사용이 되었다. 유기중합물 처리에 따른 페레니얼 라이그래스의 색, 품질, 성장에 미치는 영향은 나타나지 않았다. 그러나 유기중합물이 토양입단화에는 토양의 종류에 따라 영향이 있는 것으로 나타났다. 본 실험의 결과의 구체적인 실증을 위해서 필드 실험이 필요한 것으로 판단이 된다.

• 한국환경복원기술학회지
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• 제5권4호
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• pp.1-9
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• 2002

This study is carried out to make the environmentally affinitive porous planting block for revegetation and to make a effective program for greening plans. The summary is shown below. 1. In order to get stronger intensity and distribute proper porosity in the block for planting, the cements mixed with fine soil were used and the finer in soil grains gives the stronger in intensity of the cements. Use of the furnace slag cements instead of the portland cements showed relatively stronger in intensity of the block. The intensity of the block became stronger when the mixed ratio of the cements to soil is 5 : 1, but the pore space ratio was lower. The percolate pH of the portland cements after one month of treatment was 13.1 but the percolate pH of the furnace slag cements was shown lower. To mold proper porous planting blocks, the proper combination of additives such as the dehydrating agent, elastic agent and adhesives into the mixture of cements and soil gives better effectives. 2. After molding the porous planting blocks, it gave a better result when the grains of the filler made of peat moss, upland soil and compound fertilizer were smaller than 2 mm in size. Shaking of the filling materials also gave the better result, but it took more time and cost much more. Therefore, it was better when the filling materials were mixed with water first then flew down for stuffing. 3. It was necessary to cover with soil after seeding or planting on the porous planting blocks. The proper thickness of the soil to help root development and keep moisture is about 3~5 cm. 4. The plants for planting on the porous planting block were required stronger in the growth condition of their roots and their environmental adaptability. The average germination percentage and rate of Platycodon grandiflorum on the porous planting block were 88.8% and 85% accordingly and their rate is very uniform. The germination rates of Dianthus superbus var. longicalycinus and Taraxacum officinale were more than 50%. These grass species, Chelidonium majus var. asiaticum, Lysimachia mauritiana and Scabiosa mansenensis were the suggested biennial grasses in the planting area where exchanging of the seedling or nursery plants was not necessary because their germination rates were 59.3, 45.6 and 40.3% accordingly. Viola kapsanensis, Chrysanthemum sp., Taraxacum sp. and Iris ensata var. spontanea are the grass species that could be used by seeding for greening. However, the germination rate of Solidago virga-aurea var. asiatica, Aster scaber and Lythrum anceps were lower than 10%. The coverage ratio of Ixeris stolonifera is more than 80% after 60 days seeding and the root length of most of species are more than 10 cm except Iris ensata var. spontanea and Platycodon grandiflorum because their root developed thicker than other species.

• 한국기후변화학회지
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• 제8권4호
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• pp.305-312
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• 2017

We aimed at investigating the difference in $N_2O$ emission factors of chemical and organic fertilizers and identifying the main factors influencing annual fluctuations in $N_2O$ emission. We conducted two-year experiments in 2016 and 2017 in an agricultural field planted with sweet potato (Ipomoea batatas). Treatments included chemical NPK fertilizer (NPK) and chicken compost application at $10\;ton\;ha^{-1}$, $20\;ton\;ha^{-1}$, and $30\;ton\;ha^{-1}$ rates (CK1, CK2 and CK3). Control was also employed with no addition. Results showed that $N_2O$ emission rates were significantly related with soil water status and soil available N contents. Significant correlation between % water filled pore space (WFPS) and $N_2O$ emission was observed only when the %WFPS was greater than 40% and during the initial stage of the experiment (<60 d). Comparison of the emission factors in 2016 and 2017 showed us that the emission factor was greater in 2016 when the %WFPS was maintained higher by 16.5% compared to that in 2017. In 2016, the emission factor of organic fertilizer was higher than that of chemical fertilizer, while in 2017, the pattern was reversed. Annual variability in $N_2O$ emission could also be originated from the available N contents remaining in soil after being taken up by plants. If we apply excessive N fertilizer, the soil would contain excess amount of N which was not uptaken by plants, leading to a huge increase in $N_2O$ emission. This case would overestimate emission factor, which was the case for the organic fertilizer in 2016. Over-fertilization should be avoided when we set up an experiment to determine $N_2O$ emission factor.