• 제목/요약/키워드: alluvial soil

검색결과 163건 처리시간 0.022초

입지조건이 다른 시설재배지에서 담수처리에 따른 양분 용탈량 평가 (Evaluation of Nutrient Discharges from Greenhouses with Flooding Soil Surface at Two Different Locations)

  • 김민경;노기안;고병구;박성진;정구복;이덕배;김철수
    • 한국토양비료학회지
    • /
    • 제43권3호
    • /
    • pp.315-321
    • /
    • 2010
  • 시설재배는 폐쇄된 환경에서 제한적인 물관리로 인하여 작기 중에는 외부에 영향을 미치지 않으나, 작물 생산 이후 토양 중 집적된 염류를 제거하기 위해 담수처리를 하게 되는데, 이 때 토양 중 염류가 지표유출 및 용탈을 통하여 주변 수질에 영향을 직접 미치고 있어서 이에 대한 정량적인 평가를 하였다. 입지조건이 다른 두 시설재배지인 경북 상주시 서곡동에 위치한 시설하우스에서 2008년 7월 중순부터 9월 중순까지 시험 전 후의 토양 화학성, 관개량 및 관개수질, 침투수량 및 침투수질, 표면수질, 그리고 조사기간 동안 주변 하천 수질을 조사하였다. 하성평탄지에서는 담수직후의 제염률은 60.4%로 곡간지에 비해 훨씬 높았으며 76.6%까지 높아졌다가 담수 20일 후에는 66.7%이었다. 담수초기부터 곡간지의 표면수중 $NH_4$-N과 $PO_4$-P 농도가 하성평탄지보다 높았으며, 곡간지에서 담수직후와 담수종료 후의 토양깊이별 $Cl^-$${SO_4}^{2-}$ 농도는 큰 차이가 있었으나, 하성평탄지에서는 토양깊이별 ${SO_4}^{2-}$ 농도만 차이가 있었다. 침투수중 $NO_3$-N 농도 변화는 곡간지에 비해 하성평탄지에서 변화의 폭이 컸으며, 시간이 경과할수록 그리고 토양이 깊어질수록 그 농도도 높았다. 또한, 곡간지와 하성평탄지에 있는 시설재배지에서 담수제염에 의한 질소와 인수지를 비교 평가해 본 결과 곡간지와 하성평탄지 모두 유입 부하량보다 유출 부하량이 많아 외부 수계의 영향을 주는 것으로 평가되었다. 특히, 곡간지에 비해 하성평탄지에서의 양분 부하량이 더 많은 것으로 평가되었는데, 곡간지에서는 지하용탈만으로 제염을 하여 지하수의 수질에 영향을 주고 하성평탄지에서는 지하용탈뿐만 아니라 지표용탈에 의한 제염으로 인해 하천수의 수질에 영향을 주는 것으로 평가되었다.

지하수 수위 변동을 이용한 지하수 함양률 산정(전주-완주, 곡성 지역)

  • 조민조;하규철;이명재;이진용;이강근
    • 한국지하수토양환경학회:학술대회논문집
    • /
    • 한국지하수토양환경학회 2002년도 총회 및 춘계학술발표회
    • /
    • pp.217-220
    • /
    • 2002
  • To investigate the conditions of groundwater resources In Jeonju, Wanju, and Goksung, a basic groundwater survey was performed. From the survey, various useful informations such as groundwater use, waterlevel distribution, water chemistry were obtained. This study focused on the analysis of the water levels, which were automatically monitored with pressure transducers or manually measured. The monitorings were conducted for both shallow wells completed in alluvial aquifers and deep wells in bedrock aquifers. The automatically monitored waterlevels for alluvial aquifer were also used for estimation of recharge in the study area. This study presents results of the investigation.

  • PDF

Hydrogeochemical processes and behavior of nitrate in an dlluvial aquifer: A preliminary result from Cheonan area, Korea

  • Kim, Kyoung-Ho;Yun, Seong-Taek;Choi, Byoung-Young;Kim, Kang-Joo
    • 한국지하수토양환경학회:학술대회논문집
    • /
    • 한국지하수토양환경학회 2004년도 총회 및 춘계학술발표회
    • /
    • pp.97-99
    • /
    • 2004
  • To understand the geochemical processes controlling the distribution of nitrate and other agricultural constituents in an alluvial aquifer, hydrogeological and hydro geochemical studies were carried out in an agricultural area within Cheonan. In this selected field, nitrate concentrations were very wide in range but was locally attenuated significantly down to very low levels (<1.0 mg/L). Abrupt removal of nitrate coincided with the pattern of redox change and thus indicated that geochemical processes occurring during and after recharge events control the behavior and distribution of nitrate and other redox-sensitive chemical species.

  • PDF

Hydrochemistry of an alluvial aquifer in the Cheonan area: role of the pyrite oxidation on denitrification

  • Kim, Kyoung-Ho;Yun, Seong-Taek;Chae, Gi-Tak;Heo, Chul-Ho;Kim, Hyoung-Soo;Rhee, Chul-Woo;Kim, Kangjoo
    • 한국지하수토양환경학회:학술대회논문집
    • /
    • 한국지하수토양환경학회 2002년도 추계학술발표회
    • /
    • pp.287-290
    • /
    • 2002
  • To examine the denitrification process in an alluvial aquifer in the Cheonan site, hydrological and hydrogeochemical studies were carried out. Elevated levels of NO$_3$ (maximum 77.6 mg/L) were observed in shallow groundwaters of the area, as a result of poultry and agricultural activity. However, the nitrate concentrations were found to be consistently attenuated down to very low levels (<1.0 mg/L). The abrupt removal of nitrate coincided with the pattern of redox change and indicated that denitrification is the most plausible process. The hydrochemistry and mass balance approach using geochemical modeling (phreeqc 2.0) and redox chemistry indicated that chemo-autotrophic denitrification via pyrite oxidation is the key Process to control the nitrate attenuation in the study area.

  • PDF

Long-Term Investigation of Regional Topographic Effects on Soil Chemical Properties and Heavy Metal Concentrations in Paddy Fields

  • Ahn, Byung-Koo;Kang, Seong-Soo;Shin, Jae-Yeon;Lee, Jin-Ho
    • 한국토양비료학회지
    • /
    • 제45권5호
    • /
    • pp.738-743
    • /
    • 2012
  • Topographic conditions of agricultural fields work as a important factor to identify different soil properties. This study was conducted to investigate the selected soil chemical properties and the concentrations of heavy metals, Cd, Cr, Pb, Cu, Ni, and Zn, in the paddy fields of different topographic areas at four year intervals from 1999 to 2011. Three-hundred soil sampling sites in the paddy fields were selected from the different topographic areas that were local valley and fans, fluvio-marine deposits, alluvial plains, and diluvial terraces. The mean values of soil pH ranged 5.7~5.8 that were within optimal range for rice cultivation. The mean values of other properties such as soil organic matter (SOM) content, the concentrations of exchangeable cations, $K^+$, $Ca^{2+}$, and $Mg^{2+}$, and available silicate concentration were lower or close to the optimal values, but the mean concentrations of available phosphorus were exceeded the range of optimal value, $80{\sim}120mg\;kg^{-1}$, in many paddy fields. In particular, The concentrations of available phosphorus in the paddy fields of local valley and fans, alluvial plains, and fluvio-marine plains were mostly declined. However, in diluvial terrace areas, the phosphorus concentrations unexpectedly increased; furthermore, they were significantly higher than those in other topographic areas. The mean concentrations of 0.1 M HCl-extractable heavy metals, Cd, Cr, Pb, Cu, Ni, and Zn, in the paddy fields were slightly and gradually declined during the study years, but the Pb concentrations were not statistically changed. In addition, the concentrations of heavy metals were widely ranged depending on the different sampling sites. Nevertheless, the concentrations of heavy metals were significantly lower than the levels of Soil Contamination Warning Standard (SCWS) for agricultural lands (1-region) presented in Soil Environment Conservation Law (SECL).

국가지하수 관측망의 양수시험 자료를 이용한 국내 대수층 특성의 통계적 분석 (Statistical Analysis of Aquifer Characteristics Using Pumping Test Data of National Groundwater Monitoring Wells for Korea)

  • 전선금;구민호;김용제;강인옥
    • 한국지하수토양환경학회지:지하수토양환경
    • /
    • 제10권6호
    • /
    • pp.32-44
    • /
    • 2005
  • 국가지하수 관측망의 314개 관정에 대한 양수시험 자료를 분석하여 국내 암반 및 충적대수층이 나타내는 수리전도도 분포, 투수량계수와 비양수량과의 관계, 양수 및 회복시험 유형에 관한 통계 자료를 제시하였다. 충적대수층의 평균 수리전도도는 1.26m/day로 암반대수층(0.076 In/day)보다 약 17배 크게 나타났다. 암반대수층 수리전도도의 평균과 분산도는 국외의 결정질 균열 암반과 거의 일치하였으며, 암종별 평균값은 퇴적암, 화성암, 변성암 순으로 뚜렷한 차이를 보였다. 투수량계수 분석 결과 국가지하수 관측망의 지하수는 암반을 통하여 $32\%$, 충적층을 통하여 $68\%$ 정도가 흐르는 것으로 나타났다. 회귀분석을 통하여 국가지하수 관측망의 대수층이 나타내는 비양수량과 투수량계수의 관계식을 제시하였다 양수 및 회복시험의 수위강하 양상에 따라 대수층의 유형을 $4\~5$개로 분류하여 각 유형이 나타내는 대수층의 특성을 분석하였다 국가지하수 관측망 대수층의 대부분$(83.7\%)$은 함양경계형을 보였으며, 관측소 인근의 하천, 암반 및 충적대수층의 수리적 연결에 의한 두 대수층간의 수직적인 지하수의 흐름, 자유면대수층에서 중력배수에 의해 발생하는 지연산출 등 다양한 공급원에 의하여 함양경계형이 나타난 것으로 분석되었다.

포장재배(圃場栽培) 수도(水稻)의 무기영양(無機營養) -II 삼요소(三要素) 이용율(利用率)과 기상권(氣象圈) 및 토양단면(土壤斷面)의 물리(物理)·화학적(化學的) 성질(性質)과의 관계(關係) (Mineral Nutrition of Field-Grown Rice Plant -II Recovery of fertilizer nitrogen, phosphorus, and potassium in relation to climatic zone and physical or chemical characteristics of soil profile)

  • 박훈;신천수
    • 한국토양비료학회지
    • /
    • 제6권1호
    • /
    • pp.17-26
    • /
    • 1973
  • 수도삼요소(水稻三要素) 이용율(利用率)(1967 및 1968년(年))과 기상권(氣象圈), 답토양(畓土壤) 단면(斷面)의 추적양식(推積樣式) 배수등급(排水等級) 토성(土性) 및 작토(作土)의 토양화학적(土壤化學的) 특성(特性)과의 관계(關係)를 검토(檢討)한 결과(結果) 다음과 같은 결과(結果)를 얻었다. 1. N이용율(利用率)은 남부(南部)>중부(中部)>북부(北部)의 순(順)이고 K이용율(利用率)은 남부(南部)>북부(北部)>중부(中部)의 순(順)이며 P이용율(利用率)은 연도별(年度別)로 다르다. 2. P이용율(利用率)은 남부(南部)의 도(道)에서 연도별(年度別) 변동(變動)이 크고 추적(推積) 배수(排水) 토성별(土性別)에서도 연도별(年度別) 변동(變動)이 커서 토양(土壤)과 기상(氣象)의 교호작용(交互作用)에 크게 영향 받는것을 알 수 있다. 3. 추적양식별(推積樣式別) N이용율(利用率)은 Alluvial Colluvial (AC)>Alluvial (A)>Fluvomarine (FM)>Old Alluvial (OA)의 순(順)이고 K이용율(利用率)은 OA>AC>A>FM의 순(順)이다. 4. N이용율(利用率)은 토양단면(土壤斷面)의 배수(排水)가 양호(良好)할수록 적어지고 K와 P의 이용율(利用率)은 약간양호(若間良好)에서 높은 경향이고 불량(不良)이나 매우 양호(良好)의 편에서 낮은 경향이다. 5. N이용율(利用率)은 미사식양질(微砂埴壤質)에서 가장높고 사질(砂質)로 갈수록 떨어지며 식질(埴質)에서도 낮으나 K와 P 이용율(利用率)은 식양질(埴壤質) 이하(以下)의 토성(土性)에서 높은 경향(傾向)이다. 6. N이용율(利用率)은 지산 극락 신답통에서 크고 화동 규암 용지 화봉에서 적었다. 7. N이용율(利用率)은 토양중(土壤中) 유기물함량(有機物含量)(OM), Ca 및 CEC와 유의정상관(有意正相關)을 보이고 P이용율(利用率)이 높았던 해에만 P함량(含量)과 유의부상관(有意負相關)을 보였으며 P이용율(利用率)은 CEC, Mg 및 Ca와 유의정상관(有意正相關)을 보였다. 8. K이용율(利用率)은 그것이 적었던 해에는 K/(Ca+Mg), P, OM, K의 순(順)으로 부상관(負相關)을 Ca, Mg, CEC 순(順)으로 정상관(正相關)을 보였는데 K/(Ca+Mg)와만 유의성(有意性)이 있으며 K이용율(利用率)이 큰 해에는 P, OM, K/(Ca+Mg) K의 순(順)으로 정상관(正相關)을 CEC, Mg, Ca 순(順)으로 부상관(負相關)을 보였는네 P, OM, CEC 와만 유의성(有意性)을 갖는다. K이용율(利用率)이 컸던 해에만 토양중 K는 토양중 P 및 OM과 유의정상관(有意正相關)을 갖는다. 9. 삼요소이용율(三要素利用率)과 pH는 유의성(有意性)은 없으나 부상관(負相關)이다. 10. OM은 P K 및 K/(Ca+Mg)와 유의정상관(有意正相關)을 Mg와는 유의부상관(有意負相關)을, P는 K, K/Ca+Mg와 유의정상관(有意正相關)을 Mg 및 CEC와 유의(有意) 부상관(負相關)을 K는 K/(Ca+Mg), Mg 및 CEC와 유의정상관(有意正相關)을 K/(Ca+Mg)는 Ca와 유의정상관(有意正相關)을 Mg 및 CEC와는 유의부상관(有意負相關)을, Ca는 Mg CEC 및 pH와, Mg는 CEC와 유의(有意) 정상관(正相關)을 보였다. 11. 삼요소(三要素) 이용율(利用率) 및 토양(土壤)의 화학적(化學的) 특성(特性) 상호간(相互間)의 관계에서 OM이 시비(施肥)N의 흡수(吸收)를 돕고 K흡수(吸收)는 K보다 K/(Ca+Mg)에 의(依)하여, P흡수(吸收)는 Mg에 의(依)하여 크게 영향받는 것을 알수있고 P와 K이용율(利用率)이 해에 따라 다른 원인(原因)이 부분적(部分的)으로 설명(說明)될 수 있었다.

  • PDF

Geochemical Characteristics and Assesment of Nitrate Nitrogen in Groundwater in Yanggu-Gun, Gangwon-Do in Korea

  • Choi, Won Gyu
    • 한국지하수토양환경학회지:지하수토양환경
    • /
    • 제24권6호
    • /
    • pp.26-32
    • /
    • 2019
  • An analysis of groundwater quality is significant for monitoring and managing water contamination and groundwater system. For the purpose of those, the geochemical characteristics of groundwater were studied over the concern for water quality, water type and origin of nitrate nitrogen. Total colony counts were detected in 11 out of 20 samples, and the average value was 31.73 CFU/ml. Range and average of NO3-N concentrations were 0.9~24.0 mg/L and 8.3 mg/L. All groundwater types were found to be Ca2+-HCO3-. The range and average of NO3-N were 0.2~17.4 mg/L and 8.7 mg/L, and those of δ15N were 1.7~8.9‰, and 5.0‰. Careful consideration is required for evaluating the origin of nitrogen when NO3-N concentration is low. In general, noticeable difference between rockbed and alluvial water was not found. The ranges of nitrate origins by chemical fertilizer, livestock manure and domestic sewage, and natural soil were 29.6~76.4%, 14.2~58.9% and 2.6~7.0%, and the average values of those were 57.4%, 37.4%, and 5.3%, respectively. Origin of nitrate was affected by more chemical fertilizer than the other parameters. Rockbed water was more affected by chemical fertilizer than alluvial water.

Simplified analysis of creep for preloaded reconstituted soft alluvial soil from Famagusta Bay

  • Garoushi, Ali Hossien Basheer;Uygar, Eris
    • Geomechanics and Engineering
    • /
    • 제28권2호
    • /
    • pp.157-169
    • /
    • 2022
  • Preloading of soft clays is a common ground stabilization method for improvement of compressibility and the undrained shear strength. The waiting period under preload is a primary design criterion controlling the degree of improvement obtained. Upon unloading the overconsolidation attained with respect to actual loads defines the long term performance. This paper presents a laboratory study for investigation of creep behavior of Famagusta Bay alluvial soft soil preloaded under various effective stresses for analysis of long term performance based on the degree of overconsolidation. Traditional one-dimensional consolidation tests as well as modified creep tests are performed on reconstituted soft specimens. Compressibility parameters are precisely backcalculated using one dimensional consolidation theory and the coefficient of creep is determined using the traditional Cassagrande method as well as two modified methods based on log cycles of time and the inflection of the creep curve. The test results indicated that the long term creep can be successfully predicted considering the proposed method. The creep coefficients derived as part of this method can also be related to the recompression index (recompression index, swelling index) considering the results of the testing method adopted in this study.

Hydrogeochemical study of a watershed in Pocheon area: controls of water chemistry

  • Kim, Kyoung-Ho;Yun, Seong-Taek;Chae, Soo-Ho;Jean, Jong-Wook;Lee, Jeong-Ho;Kweon, Hae-Woo
    • 한국지하수토양환경학회:학술대회논문집
    • /
    • 한국지하수토양환경학회 2004년도 임시총회 및 추계학술발표회
    • /
    • pp.121-121
    • /
    • 2004
  • The groundwater in the Pocheon area occurs from both a fractured bedrock aquifer in igneous and metamorphic rocks and an alluvial aquifer with a thickness of <50 m, and forms a major source of domestic and agricultural water supply. In this study, we performed a hydrogeochemical study in order to identify the control of geochemical processes on groundwater quality. For this study, groundwater level and physicochemical parameters (EC, Eh, pH, alkalinity) were monitored once a month from a total of 150 groundwater wells between June 2003 to August 2004. A total of 153 water samples (13 surface water, 66 alluvial groundwater, 74 bedrock groundwater) were also collected and analyzed in February 2004. Groundwater chemistry in the study area is very complex, depending on a number of major factors such as geology, degree of chemical weathering, and quality of recharge water. Hydrochemical reactions such as the leaching of surficial and near-solace soil salts, dissolution of calcite, cation exchange, and weathering of silicate minerals are proposed to explain the chemistry of natural groundwater. Alluvial groundwaters locally have very high TDS concentrations, which are characterized by their chloride(nitrate)-sulfate-bicabonate facies and low Na/Cl ratio. Their grondwater levels are highly fluctuated according to rainfall event. We suggest that high nitrate content and salinity in such alluvial groundwaters originates from the local recharge of sewage effluents and/or fertilizers. Likewise, high concentrations of nitrate were also locally observed in some bedrock groundwaters, suggesting their effect of anthropogenic contamination. This is possibly due to the bypass flow taking place through macropores. Tile degree of the weathering of silicate minerals seems to be a major control of the distribution of major cations (sodium, calcium, magnesium, potassium) in bedrock groundwaters, which show a general increase with increasing depth of wells. Thermodynamic interpretation of groundwater chemistry shows that the groundwater in the study area is in chemical equilibrium with kaolinite and Na-montmorillonite, which indicates that weathering of plagioclase to those minerals is a major control of hydrochemistry of bedrock groundwater. The interpretation of the molar ratios among major ions, as well as the mass balance calculation, also indicates the role of both dissolution/precipitation of calcite and Ca-Na cationic exchange as bedrock groundwaters evolves progressively.

  • PDF