• 한국토양비료학회지
• /
• 제33권2호
• /
• pp.79-84
• /
• 2000

주요 과수재배지 토양에 대한 화학적 독성을 파악하기 위하여 사과 239, 배 369, 포도 168, 복숭아 101, 합계 877포장에서 주간 중간지점의 토양을 채취분석하여 토양화학적 특성에 따라 토양비옥도를 구분하였다. 주요 과수 주산단지 토양화학성분의 적정수준 비율은 3.0~65.2%로서 대부분의 과수원이 부적지였으며 토양층위별 화학성분은 하층으로 내려 갈수록 일정하게 감소되는 경향을 보여 시비관리가 동일한 지역에서는 표층토 20cm 깊이의 토양 화학성분 함량만 알면 층토의 성분함량을 추정할 수 있으며 또한 과종별 표토의 토양화학성분함량의 과부족율을 추정할 수 있었다.

• Journal of electromagnetic engineering and science
• /
• 제10권4호
• /
• pp.212-218
• /
• 2010

The radar backscatter from various earth surfaces is sensitive to the frequency of the incident wave. This study examined the radar sensitivities for surface parameters such as soil moisture content and surface roughness of both bare and vegetated surfaces at X-band. Because L-band frequencies are often used for sensing the surface parameters, the sensitivities of X-band are also compared with those of the L-band. The sensitivities of the X-band radar backscatter were examined with respect to soil moisture content and surface roughness of rough bare soil surfaces. These sensitivities were also examined using the same parameters for vegetated surfaces for various vegetation densities and incidence angles. Use of the X-band radar for soil moisture detection was as effective as L-band radar for bare soil surfaces. For vegetated surfaces, the soil moisture could be detected using an X-band radar at lower incidence angles, where the upper limit of the incidence angles was dependent on vegetation density.

• 대한원격탐사학회지
• /
• 제30권3호
• /
• pp.375-381
• /
• 2014

Soil moisture is an essential satellite-driven variable for understanding hydrologic, pedologic and geomorphic processes. The European Space Agency (ESA) has endorsed soil moisture as one of Climate Change Initiates (CCI) and had merged multi-satellites over 30 years. The $0.25^{\circ}$ coarse resolution soil moisture satellite data showed correlations with variables of a water stress index, Temperature-Vegetation Dryness Index (TVDI), from a stepwise regression analysis. The ancillary data from TVDI, Land Surface Temperature (LST) and Normalized Difference Vegetation Index (NDVI) from MODIS were inputted to a multi-regression analysis for estimating the surface soil moisture. The estimated soil moisture was validated with in-situ soil moisture data from April, 2012 to March, 2013 at Andong observation sites in South Korea. The soil moisture estimated using satellite-based LST and NDVI showed a good agreement with the observed ground data that this approach is plausible to define spatial distribution of surface soil moisture.

• 한국물환경학회지
• /
• 제28권1호
• /
• pp.137-147
• /
• 2012

Land surface temperature in ecohydrology is a variable that links surface structure to soil processes and yet its spatial prediction across landscapes with variable surface structure is poorly understood. And there are an insufficient number of soil temperature monitoring stations. In this study, a grid-based land surface temperature prediction model is proposed. Target sites are Andong and Namgang dam region. The proposed model is run in the following way. At first, geo-referenced site specific air temperatures are estimated using a kriging technique from data collected from 60 point weather stations. Then surface soil temperature is computed from the estimated geo-referenced site-specific air temperature and normalized difference vegetation index. After the model is calibrated with data collected from observed remote-sensed soil temperature, a soil temperature map is prepared based on the predictions of the model for each geo-referenced site. The daily and monthly simulated soil temperature shows that the proposed model is useful for reproducing observed soil temperature. Soil temperatures at 30 and 50 cm of soil depth are also well simulated.

• 한국토양비료학회지
• /
• 제42권2호
• /
• pp.139-143
• /
• 2009

인지질 지방산을 분석하여 특정 미생물군의 수직적 분포와 토층간 미생물 군집 패턴을 조사하였다. 경북 농업기술원에 위치하고, 질소, 인산, 가리의 화학비료만 장기 연용한 논과 밭 포장에서 15 cm 깊이까지 토양을 채취하였다. 인지질 지표 지방산을 주요인 분석으로 분석하여 토양 미생물 군집을 분석한 결과 논과 밭 토양의 미생물 군집은 뚜렷하게 구분되었으며, 토층간 차이보다 논과 밭의 차이가 더 컸다. 논보다 밭은 토층이 깊어짐에 따라 미생물 군집이 급격하게 변하였는데, 미생물 군집 측면에서 밭보다 논의 표층이 더 두껍다고 볼 수 있다. cyclopropyl/monoenoic precursor 비율과 전체 포화지방산/전체 불포화 지방산 비율은 토심이 깊어짐에 따라 증가하였는데, 이는 토심이 깊어질수록 탄소원과 통기가 부족하기 때문에 일어나는 현상으로 보인다. 대체로 표토는 그램음성균, 곰팡이 등의 상대적 비율이 높고 토심이 깊어질수록 세균과 방선균의 상대적 비율이 높아졌다.

• 한국환경과학회지
• /
• 제8권2호
• /
• pp.145-150
• /
• 1999

To estimate the thermal effect of the vegetation canopy on the surface sublayer environment numerically, we used the combined model of Pielke's1) single layer model for vegetation and Deardorff's2) Force restore method(FRM) for soil layer. Application of present combined model to three surface conditions, ie., unsaturated bare soil, saturated bare soil and saturated vegetation canopy, showed followings; The diurnal temperature range of saturated vegetation canopy is only 20K, while saturated bare soil and unsaturated bare soil surface are 30K, 35K, respectively. The maximum temperature of vegetation canopy occurs at noon, about 2 hours earlier than that of the non-vegetation cases. The peak latent heat fluxes of vegetation canopy is simulated as a 600Wm-2 at 1300 LST. They have higher values during afternoon than beforenoon. Furthermore, the energy redistribution ratios to latent heat fluxes also increased in the late afternoon. Therefore, oasis effect driving from the vegetation canopy is reinforced during late afternoon compared with the non-vegetated conditions.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2013년도 추계 학술논문 발표대회
• /
• pp.80-81
• /
• 2013

There is the increasing number of constructing soil or structure on the soft ground during public works. Usually cement or slag cement has been the traditional material for surface soil stabilization method. Recently, early strength development properties of hardening agent is required for driving abilities of execution equipment and shortening of the construction time. Therefore, the purpose of this study is to develop the early compressive strength hardening agent for surface soil stabilization. The study was confirmed performance and availability of hardening agent using early strength type cement and industrial by-product minerals through early strength development properties in accordance with water cement ratio, content of hardening agent for soft soil.

• 한국물환경학회지
• /
• 제25권5호
• /
• pp.785-791
• /
• 2009

Using artificial rainfall simulator, the soil loss, which is deemed as the most cause of muddy water problem among Non-point source (NPS) pollutant, was studied by the analysis of direct runoff, groundwater discharge, and soil water storage properties concerned with rainfall intensity, slope of area, and land cover. The direct runoff showed increasing tendency in both straw covered and bared soil as slope increases from 5% to 20%. The direct runoff volume from straw covered surface were much lower than bared surface. The infiltration capacity of straw covered surface increased, because the surface sealing by fine material of soil surface didn't occur due to the straw covering. Under the same rainfall intensity and slope condition, 2.4~8.2 times of sediment yield were occurred from bared surface more than straw covered surface. The volume of infiltration increased due to straw cover and the direct runoff flow decreased with decrease of tractive force in surface. To understand the relationship of the rate of direct runoff, groundwater discharge, and soil water storage by the rainfall intensity, slope, and land cover, the statistical test was performed. It shows good relationship between most of factors, except between the rate of groundwater storage and rainfall intensity.

• 한국산림과학회지
• /
• 제107권1호
• /
• pp.108-111
• /
• 2018

토양 표면에 요면(굴곡)을 형성하는 것은 토양의 거칠기를 증가시켜 강우의 침투와 토양의 저류능력을 향상시키고 지표수 및 토사의 유실량을 감소시키는 효과적 방법이 될 수 있다. 이 연구에서 토양 표면에 형성된 요면의 모양이 지표수의 흐름에 반구형일 때 수평 및 수직형일 때보다 침투량이 많았고, 토양의 저류능력은 수직형 요면에서 높았다. 흙 파기, 또는 토양 표면의 요면 형성은 산림 토양에서 산불 발생 후 대책으로, 또 건기 때 가뭄 스트레스를 해소하는 실용적인 방법으로 활용될 수 있다.

• 대한토목학회논문집
• /
• 제14권3호
• /
• pp.535-542
• /
• 1994

원격 측정 방법은 지표로부터 방출된 방사선의 관측으로부터 지표면의 특성을 추정하는데 기초를 두고 있으며 이 방법을 사용하여 연구되어지는 수문학적 인자에는 지표면 온도, 증발산, 토양 함수비, 강우 그리고 강설 등이 있다. 본 연구에서는 관측된 광명온도와 모의된 광명온도로부터 피복이 안된 토양의 함수비 산정에 대한 방법을 소개한다. 피복이 안된 토양에서의 초단파 방출은 함수비, 토양의 온도와 표면 조도에 의존하게 된다. 이 방법은 표면 조도의 영향을 고려하기 위한 Fresnel 반사 계수의 수정과 함께 방사선 전달 모델(radiative transfer model)에 기본을 두고 있는데 피복이 안된 매끈한 표면과 서로 다른 표면 조도를 가진 표면에 대해 분석을 실시한다. 연구의 결과는 표면 조도의 영향이 토양의 광명온도를 증가시키고 광명온도와 함수비 사이의 감소경사를 작게함을 보여주고 있다.