• Title/Summary/Keyword: Soil condition

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An Analysis of Major Trail Deterioration in Urban Natural Park - A Focus on Apsan Park in Daegu Metropolitan City - (도시자연공원의 주요 등산로 훼손실태 분석 - 대구광역시 앞산공원을 대상으로 -)

  • Park, In-Hwan;Lee, Hea-Young;Cho, Kwang-Jin;Jang, Gab-Sue
    • Journal of the Korean Institute of Landscape Architecture
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    • v.38 no.3
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    • pp.33-40
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    • 2010
  • Many trails have been built and utilized in each sub-basin of Apsan Park. This study focused on the conditions and the present flora of several overused trails within three basins called Kun-Gol, Anjiroung-Gol, and Meaja-Gol in Apsan Park. There are two purposes for this study. The first is to make a plan for restoration by classifying the type of damage to these overused trails. The second is to provide preliminary data for reestablishing a more pleasant urban nature park. As a result of the survey, the average length of these trails is 9.0km and mean width is 2.0 to 2.6m. 2,108m of the sections studied(23.4% of the total) had exposed root, 3,199m of the sections studied (35.5% of the total) had exposed rock, 3,270m of the sections studied(36.6% of the total) displayed damaged pathways, and 4,841m of the sections studied (53.8% of the total) had higher soil hardness. Eighty-three areas of deterioration were found and there has been extensive property destruction. As an indication of human disturbances, the Naturalization Index and Urbanization Index appeared as: Kun-Gol, 7.0%, 5.5%; Anjiroung-Gol, 8.3%, 4.5%; Meaja-Gol 8.6%, 6.2%; in total, 7.8%, 8.3%. As a method of checking the level and extent of the damage process, an impact rating classification was used at each point on the trails. Kun-Gol had the highest rating and Anjiroung-Gol had the lowest rating in impact rating classification. With the impact rating classification, it was found that each trail would continue to worsen, meaning that roots and rocks are more likely to be further exposed and the trail width will continue to widen through overuse. An actual plan for reparations and restoration of the trails is needed through further study.

Effects of Environment Friendly Agricultural Materials to Insect Parasitoids in the Laboratory (실내조건에서 친환경농자재가 기생성 천적곤충에 미치는 영향)

  • Yu, Yong-Man;Kang, Eun-Jin;Seo, Mi-Ja;Kang, Myeng-Gi;Lee, Hee-Jin;Kim, Da-A;Gil, Mi-La;Youn, Young-Nam
    • Korean journal of applied entomology
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    • v.45 no.2 s.143
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    • pp.227-234
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    • 2006
  • For the biological control of the greenhouse whitefly, aphids, American leaf-miners, Encarsia formosa, Aphidius coiemani, Diglyphus isaea, and Dacnusa sibirica were used as biological control factors. Otherwise, many kinds of environment friendly agricultural materials were also used in the kindly environment friendly farming. For testing the toxicity of environment friendly agricultural materials against to insect parasitoids as biological control factors, 61 environment friendly agricultural materials were selected by using methods and periods with insect parasitoids in the greenhouses. Environment friendly agricultural materials were sprayed to mummies and adults of E. formosa and A. colemani, and adults of Diglyphus isaea and Dacnusa sibirica in laboratory condition. Emergence rates were checked during 12 days after spray to mummies of E. formosa and A. colemani, and survival rates were at 24 and 48 hours after viral test for adult parasitoids, with 10% sugar solution. Emergence rates of E. formosa mummies were inhibited by sprayed the fungicidal environment friendly agricultural material (FEFAM) E and the environment friendly agricultural materials contained molybdenum (EFAMMo) G as 0.4 and 2.7%, respectively. E. formosa adults were not survived in vial for 48hours after sprayed and dried with the environment friendly agricultural materials contained plant extract (EFAMPE) J and the EFAMMo C. The environment friendly agricultural materials contained microelements (EFAMMEs) B and EFAMPE H, environment friendly agricultural materials contained useful soil microorganisms (EFAMSMs) H, FEFAM A and FEFAM D were recorded low survival rates of E. formosa adults with 6.7, 13.3, 13.3, 20.0 and 20.0, respectively. In case of the spraying environment friendly agricultural materials to mummies of A. colemani there were low emergence rate from mummies to adults as around 20s % with water spraying as control. A. colemani adults were not survived in vial with EFAMMo C. EFAMPE J, EFAMPE F, EFAMPE H, EFAMSM H were recorded low survival rates under 20% as 6.7, 13.3, 13.3 and 13.3, respectively, D. isaea and D. sibirica adults were not survived in vial with EFAMPE J. EFAMMo C was 53.3% of survival rates in 48 hours vial tests. D. isaea and D. sibirica were not affected by environment friendly agricultural materials compared with E. formosa and A. colemani.

Settlement Instrumentation of Greenhouse Foundation in Reclaimed Land (간척지 온실 기초의 침하량 검토)

  • Choi, Man Kwon;Yun, Sung Wook;Yu, In Ho;Lee, Jong-Won;Lee, Si Young;Yoon, Yong Cheol
    • Journal of Bio-Environment Control
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    • v.24 no.2
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    • pp.85-92
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    • 2015
  • This study examined the settlement of a 1-2W type greenhouse using a timber pile, which was recently established on Gyehwa-do reclaimed land, in order to obtain base data for the construction of a greenhouse on reclaimed land. The results of this study are as follows. foundation and timber pile increased over time, irrespective of the interior and exterior of the upon investigation of the ground, it was confirmed that there was no soft rock stratum (bedrock), and that a sedimentary stratum existed under the fill deposit, which is estimated to have been reclaimed during the site renovation. It was also found that a weathered zone was located under the fill deposit and sedimentary stratum, and that the soil texture of the entire ground floor consisted of clay mixed with sand, silty clay, and granite gneiss, in that order, regardless of boreholes. In addition, the underground water level was 0.3m below ground, regardless of boreholes. Despite a slight difference, the settlement of the greenhouse or measurement sites (channels). With regard to the pillar inside the greenhouse, except in the case of CH-2, the data at a site located on the side wall of the greenhouse (wind barrier side) indicated vibrations of relatively larger amplitude. Moreover, the settlement showed a significant increase during a certain period, which was subsequently somewhat reversed. Based on these phenomena, it was verified that the settlement range of each site in the interior and exterior of the greenhouse was between 1.0 and 7.5mm at this time, except in the case of CH-1. The results of the regression analysis indicated good correlation, with the coefficient of determination by site ranging between 0.6362 and 0.9340. Furthermore, the coefficient of determination ranged between 0.6046 and 0.8822 on the exterior of the greenhouse, which is lower than inside the greenhouse, but still indicates significant correlation.

A Study on the Seasonal Color Characteristics of Warm- and Cool-Season Grasses II. Color Characteristics and Life-span of Leaves in Turfgrasses and Cover Plants+ (난지형 및 한지형 지피식물의 엽색변화에 관한 연구 II. 엽색특성 및 엽수명연장)

  • 심재성;민병훈;서병기
    • Asian Journal of Turfgrass Science
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    • v.9 no.4
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    • pp.293-316
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    • 1995
  • Nitrogen fertilization and cutting practice were studied on turfgrasses and cover plants to investigate the possibility of maintaining green color during the growing season. Research also involved the effect of the nitrogen on a few morphological characteristics of leaf performance elements which might give an information to coloration and life-span of turf leaves. Treatments in the first experiment undertaken on pot included one N level: 350kgN /ha applied as compound fertilizer in split applications of one-half in mid-May and the rest both in late June and August, and four spring-summer cuts: late May, late June, late July and late August. The soil filled in pot a moderately well-drained sandy loam. In the second experiment(field observation) leaf length and width, inflorescence and flowering, and color performance were also investigated. With nitrogen fertilizer applied on turfs, desirable turf color was maintained during a period of poor coloration in specific seasons such as mid-summer for cool season grasses and late fall for warm season grasses comparing to the non-treatment. However, this was not stimulated by cutting treatment to nitrogen status existed. Cutting effect on coloration was more remarkable in both Korean lawngrass and Manilagrass than in cool season turfgrasses such as Italian rye-grass, perennial ryegrass and tall fescue. Especially down-slide of leaf color in cool season turfgrasses could he detected in mid-summer /early fall season ranging up to mid-September. In early November as well as mid-September, Italian ryegrass, perennial ryegrass and tall fes-cue retained a high level of green color as followed by nitrogen application and cutting treatment, and little detectable variation of leaf color notation between cool season turfgrasses was obtained. However, Korean la'vngrass and Manilagrass failed to retain the green color until early November. Color notations in cool season turfgrasses investigated early November on the final date of the experiment ranged from 5 GY 3/1 to 4/8 in 'Ramultra' Italian ryegrass, 'Reveile' perennial ryegrass and 'Arid' tall fescue, but those in Zoysiagrasses were 7.5 YR 4/8 in Korean lawngrass and 2.5 y 5 /6 in Manilagrass. Life-span of leaves was shorter in Italian ryegrass, perennial ryegrass and tall fescue than in beth Korean lawngrass and Manilagrass with and without nitrogen application. In general, leaves appeared in early May had a long life-span than those appeared in late April or mid-June. Nitrogen application significantly prolonged the green color retaining period in perennial ryegrass, Italian ryegrass, Korean lawngrass and Manilagrass, and this was contrasted with the fact that there was no prolonged life-span of leaves emerging in early May and mid-June in tall fescue. SPAD reading values in 48 turfs and cover plants investigated in the field trial were increasing until late June and again decreasing till September. Increasing trends of reading value could be observed in the middle of October in most of grasses. On the other hand, clovers and reed canarygrasses did not restore their color values even in October. Color differences between inter-varieties, and inter-species occurred during the growing season under the field condition implicated that selection of species and /or cultivars for mixture should be taken into consideration. In Munsell color notation investigated in the final date in the middle of November, 32 cultivars belonged under the category of 5 GY and 10 cultivars under the category of 7.5 GY. This was implying that most of cool season turfs and cover plants grown in the center zone of Korean Peninsula which are able to utilize for landscape use can bear their reasonable green color by early or mid-November when properly managed. The applicable possibilities of SPAD readings and Munsell color notation to determine the color status of turfgrasses and cover plants used in this study were discussed.

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Effect of Temperature and Various Pre-treatments on Germination of Hippophae rhamnoides Seeds (갈매보리수나무 종자의 온도 및 여러 가지 전처리에 따른 발아반응)

  • Choi, Chung-Ho
    • Korean Journal of Plant Resources
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    • v.25 no.1
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    • pp.132-141
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    • 2012
  • This study was carried out to test seed germination responses to temperatures and pre-treatments in Hippophae rhamnoides, which has many abilities in antioxidant activity, soil improvement and erosion control. H. rhamnoides seeds were placed at 10, 15, 20, 25, 30 and $35^{\circ}C$ under light condition. As the results, germination percentage (GP) was the highest at 15 and $20^{\circ}C$, and mean germination time (MGT), germination rate (GR) and germination value (GV) were the highest at $25^{\circ}C$. Quadratic and linear regression model were used to determine the cardinal temperatures such as base ($T_b$), maximum ($T_m$) and optimum ($T_o$) temperature for germination. In quadratic regression model using PG, $T_b$, $T_m$ and $T_o$ was estimated as 0.6, 36.4 and $18.5^{\circ}C$, respectively, and temperature range for germination was $35.8^{\circ}C$. In linear regression model using GR, $T_b$, $T_m$ and $T_o$ was estimated as 8.3, 35.4 and $25.3^{\circ}C$, respectively, and temperature range for germination was $27.2^{\circ}C$. Germination properties were investigated after H. rhamnoides seeds were treated by prechilling (1, 2, 4, 6 and 8 weeks), stratification (2, 4, 6 and 8 weeks), solid matrix priming (seed : carrier : water = 5 : 1 : 7, 8, 9 and 10), osmo-priming (-0.25, -0.5, -1.0 and -1.5 MPa) and calcium chloride ($CaCl_2$) -priming (100, 200, 300 and 400 mM). The highest GP was observed in $CaCl_2$ 300 and 400 mM treatments, and MGT was the shortest in stratification 6 and 8 weeks treatments. GR and GV were the highest and GP was the second highest when seeds were prechilled for 1 and 2 weeks. Consequently, prechilling 1 or 2 weeks treatment was considered as the appropriate method when we contemplate qualitative and quantitative effects in seedling production.

Isolation and Characteristics of a Phenol-degrading Bacterium, Rhodococcus pyridinovorans P21 (페놀분해세균 Rhodococcus pyridinovorans P21의 분리 및 페놀분해 특성)

  • Cho, Kwang-Sik;Lee, Sang-Mee;Shin, Myung-Jae;Park, Soo-Yun;Lee, Ye-Ram;Jang, Eun-Young;Son, Hong-Joo
    • Journal of Life Science
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    • v.24 no.9
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    • pp.988-994
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    • 2014
  • The effluents of chemical and petroleum industries often contain non-biodegradable aromatic compounds, with phenol being one of the major organic pollutants present among a wide variety of highly toxic organic chemicals. Phenol is toxic upon ingestion, contact, or inhalation, and it is lethal to fish even at concentrations as low as 0.005 ppm. Phenol biodegradation has been studied in detail using bacterial strains. However, these microorganisms suffer from substrate inhibition at high concentrations of phenol, whereby growth is inhibited. A phenol-degrading bacterium, P21, was isolated from oil-contaminated soil. The phenotypic characteristics and a phylogenetic analysis indicated the close relationship of strain P21 to Rhodococcus pyridinovorans. Phenol biodegradation by strain P21 was studied under shaking condition. The optimal conditions for phenol biodegradation by strain P21 were 0.09% $KNO_3$, 0.1% $K_2HPO_4$, 0.3% $NaH_2PO_4$, 0.015% $MgSO_4{\cdot}7H_2O$, 0.001% $FeSO_4{\cdot}7H_2O$, initial pH 9, and $20-30^{\circ}C$, respectively. When 1,000 ppm of phenol was added to the optimal medium, the strain P21 completely degraded it within two days. Rhodococcus pyridinovorans P21 could grow in up to 1,500 ppm of phenol as the sole carbon source in a batch culture, but it could not grow in a medium containing above 2,000 ppm. Moreover, strain P21 could utilize toxic compounds, such as toluene, xylene, and hexane, as a sole carbon source. However, no growth was detected on chloroform.

Utilization of $CO_2$ Influenced by Windbreak in an Elevated Production System for Strawberry (딸기 고설재배시설에서의 이산화탄소 농도 유지를 위한 방풍막 설치 효과)

  • Kim, Y.-H.;Lee, I.-B.;Chun, Chang-Hoo;Hwang, H.-S.;Hong, S.-W.;Seo, I.-H.;Yoo, J.-I.;Bitog, Jessie P.;Kwon, K.-S.
    • Journal of Bio-Environment Control
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    • v.18 no.1
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    • pp.29-39
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    • 2009
  • The influence of windbreak to minimize the ventilation velocity near the plant canopy of a greenhouse strawberry was thoroughly investigated using computational fluid dynamics (CFD) technology. Windbreaks were constructed surrounding the plant canopy to control ventilation and maintain the concentration of the supplied $CO_2$ from the soil surface close to the strawberry plants. The influence of no windbreak, 0.15 m and 0.30 m height windbreaks with varied air velocity of 0.5, 1.0 and 1.5 m/s were simulated in the study. The concentrations of supplied $CO_2$ within the plant canopy of were measured. To simplify the model, plants were not included in the final model. Considering 1.0m/s wind velocity which is the normal wind velocity of greenhouses, the concentrations of $CO_2$ were approximately 420, 580 and 653 ppm ($1{\times}10^{-9}kg/m^3$) for no windbreak, 0.15 and 0.30 m windbreak height, respectively. Considering that the maximum concentration of $CO_2$ for the strawberry plants was around 600-800 ppm, the 0.30 m windbreak height is highly recommended. This study revealed that the windbreak was very effective in preserving $CO_2$ gas within the plant canopy. More so, the study also proved that the CFD technique can be used to determine the concentration of $CO_2$ within the plant canopy for the plants consumption at any designed condition. For an in-depth application of this study, the plants as well as the different conditions for $CO_2$ utilization, etc. should be considered.

Characteristics of Shear Strength and Elastic Waves in Artificially Frozen Specimens using Triaxial Compression Tests (삼축압축실험을 이용한 인공동결시료의 강도평가 및 탄성파 특성변화)

  • Kim, JongChan;Lee, Jong-Sub;Hong, Seung-Seo;Lee, Changho
    • The Journal of Engineering Geology
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    • v.24 no.1
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    • pp.111-122
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    • 2014
  • For accurate laboratory evaluations of soil deposits, it is essential that the samples are undisturbed. An artificial ground-freezing system is the one of the most effective methods for obtaining undisturbed samples from sand deposits. The objective of this study is to estimate the shear strengths and the characteristics of elastic waves of frozen-thawed and unfrozen specimens through the undrained triaxial compression test. For the experiments, Jumunjin standard sands are used to prepare frozen and unfrozen specimens with similar relative densities (60% and 80%). The water pluviation method is used to simulate the fully saturated condition under the groundwater table. When thawing the frozen specimens, the temperature is measured every minute. After the specimens are completely thawed, undrained triaxial compression tests are conducted using the same procedures as for the unfrozen specimens. During the triaxial tests (saturation, consolidation, and shear phase), compressional and shear waves are measured. The results show that the freeze-thaw process has minor effects on the peak deviatoric stress and shear strength values, and that the process does not affect the internal friction angle. The compressional wave velocity increases with increasing B-value to 1800 m/s in the saturation phase, but tends to remain constant in the process of consolidation and shearing. The shear wave velocity decreases with increasing B-value in the process of saturation, but changes velocity in accordance with the change in effective stress in the processes of consolidation and shearing. The compressional wave velocity has similar values regardless of the freeze-thaw process, but values of shear wave velocity are slighly lower in frozen-thawed specimens than in unfrozen specimens. This study is a preliminary experiment for estimating the shear strength and characteristics of elastic wave velocity in undisturbed frozen specimens that have been obtained using the artificial ground-freezing method.

Population Dynamics of Effective Microorganisms in Microbial Pesticides and Environmental-friendly Organic Materials According to Storing Period and Temperature (저장기간 및 저장온도에 따른 미생물농약 및 친환경 유기농자재 유효미생물의 밀도변동)

  • Kim, Yong-Ki;Hong, Sung-Jun;Jee, Hyung-Jin;Shim, Chang-Kee;Park, Jong-Ho;Han, Eun-Jung;An, Nan-Hee;Lee, Seong-Don;Yoo, Jae-Hong
    • The Korean Journal of Pesticide Science
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    • v.15 no.1
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    • pp.55-60
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    • 2011
  • To work out quality control methods of environmental-friendly organic materials (EFOMs), the reason and basis for EFOM-selection and farmer's favorite formulation type of EFOMs, etc were investigated on farmers who had been practicing environmental-friendly agriculture. EFOMs used were soil amendments, control agents of plant diseases and insect pests, plant growth promotion formulations, in turns. In EFOMs application time, 22.7% of farmers sprayed EFOMs without delay after they were bought, in other hand, 77.3% of farmers used EFOMs which had been bought and stored for some period. Microbial density on seventeen environmental-friendly microbial formulates (EFMFs) including microbial pesticides, a microbial fertilizer, and environmental-friendly organic materials was investigated at different storing temperature and shelf life. When the microbial density of EFMFs was investigated without delay after they were bought, all used microbial pesticides and a microbial fertilizer was confirmed to be optimal for the certified density but two of environmental-friendly organic materials was confirmed not to be optimal. When microbial density of 17 EFMFs were investigated after storing them for six months at $4^{\circ}C$, only one of 9 microbial pesticides was confirmed not to be optimal, the other hand four of seven environmental-friendly organic materials not to be optimal, which each of their microbial density was less than the certified density. Population dynamics of microbial agents was much more influenced in fluctuated temperature (room temperature) than in static temperature condition ($5^{\circ}C$ and $25^{\circ}C$). Shelf life of microbial agents according to microbial formulation type were high in granule type, liquid wettable type and liquid type in turns.

Deterioration Characteristic Analysis for Stone Properties in the Taereung Royal Tomb of the Joseon Dynasty using Nondestructive Analysis (비파괴 분석을 활용한 조선왕릉 태릉 석조물의 손상특성 분석)

  • Lee, Myeonseong;Choie, Myoungju;Lee, Taejong;Chun, Yungun
    • Korean Journal of Heritage: History & Science
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    • v.53 no.2
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    • pp.222-241
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    • 2020
  • The Taereung Royal Tomb from the Joseon Dynasty is the tomb of Empress Munjeong, the second queen of King Jungjong, and it contains various types of stone artifacts. All of these stone artifacts were constructed using coarse- to medium-grained biotite granite. The major types of deterioration of the stone artifacts are identified as surface weathering and biological contaminants. Exfoliation (145 sculptures), granular decomposition (138 sculptures), and repair materials (156 sculptures), along with biological contaminant algae (154 sculptures), lichen (165 sculptures) and moss (97 sculptures), have a high occurrence frequency. In particular, it is deemed that immediate conservation treatment is required, as biological deterioration (algae) represents the most serious condition (grade 3 or higher in 94% of all stones), and it is thought that exfoliation and granulation decomposition are required for long-term conservation management. As a result of equo -tip hardness and ultrasonic measurement, more than 70% of stones were found to have very weak physical properties. Through hyperspectral analysis, organisms were shown to inhabit more than 80% of the surface of burial mound stone artifacts, and P (phosphorus), S (sulfur), Cl (chlorine), and Ca (calcium) were detected in this area. This is because Taereung Royal Tomb has been exposed to the outdoors for hundreds of years and has been weathered by physical, chemical, and biological factors. Therefore, among the stone artifacts in the Taereung Royal Tomb, those with high physical weathering grades are considered to require consolidation to reinforce them physically. Since organisms are highly likely to cause stone damage, they must be removed via dry and wet cleaning. In addition, in order to delay the reoccurrence of organisms following conservation treatment, it is necessary to regularly clean up the soil that has flowed into the burial mound, and to monitor conservation conditions over the long term.