• 한국농공학회논문집
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• 제63권3호
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• pp.35-45
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• 2021

Digestate or slurry produced from anaerobic digestion is mostly applied to crop lands for its disposal and recovering nutrients. However, minimizing nitrogen losses following field application of the digestate is important for maximizing the plant's nitrogen uptake and reducing environmental concerns. This study was conducted to assess the effects of three different biogas digestate application techniques (sawdust mixed with digestate (SSD), the hole application method (HA), and digestate injected in the soil (SD)) on nitrate leaching potential in the soil. A pot laboratory experiment was conducted at room temperature of 25 ± 2 ℃ for 107 days. The experimental results showed that sawdust application method turned out to be appropriate for quick immobilization of surplus N in the form of microbial biomass N, reflecting its lower total nitrogen and NH₄-N contents and low pH. The NH₄-N and total nitrogen fate in the soil fertilized with manure showed no statistically significant (p > 0.05) differences between the different methods applied during the incubation time under room temperature. In contrast, NO₃-N concentration indicates significant reduction in sawdust treatment (p < 0.05) compared to the control and other application methods. However, the soil sawdust mixed with digestate was more effective than the other methods, because of the cumulative labile carbon contents of the amendment, which implies soil net N immobilization.

• 한국환경농학회지
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• 제13권1호
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• pp.10-17
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• 1994

수질오염에 따른 Cu의 함량변화 차이를 구명하기 위하여 도시하수 및 공단배출수의 영향을 받는 만경강 유역의 논 토양을 중심으로 1982년도에 표 심토로 구분 채취한 것과 1990년도에 채취한 토양시료를, 그리고 1990년의 토양 시료채취 지역에서 재배된 수도체시료 중 Cu 함량을 분석하였다. 만경강 유역의 토양 중 Cu함량은 5.20-71.70mg $kg^{-1}$였다. 평균함량은 1990년도 토양 중의 것이 1982년도 토양에서 보다 높았다. 도시하수 유입지역으로 부터 거리 별 함량변화가 1982년보다 1990년도 토양이 보다 규칙적으로 감소되는 변화를 나타냈다. 수도체의 엽신부위의 Cu함량과 토양중의 Cu, Zn 및 Pb의 함량간에 유의성이 인정되었다. 토양 중 Cu 함량과 토양 중 Zn 및 Pb 함량간에 유의한 상관관계를 나타내고 있어서 Cu가 이들 금속들과 함께 유입되는 오염물질 임을 나타냈다. 이 지역에서 재배된 현미중 Cu함량의 범위는 0.4-10.1 mg $kg^{-1}$이었고, 수도체 부위중 최고 Cu함량은 화서축으로 현미에 비하여 2.3배 높았으며, 엽초 중의 Cu함량은 토양 중 Zn 및 Pb 함량과 상관관계를 나타냈다.

• 한국산림과학회지
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• 제76권1호
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• pp.33-40
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• 1987

잣나무(Pinus koraiensis) 파종상(播種床)에 인공산성우(人工酸性雨)로 처리(處理)하고 생장(生長), 엽내함유성분(葉內含有成分) 그리고 배지(培地) 토양(土壤)의 화학적(化學的) 성질(性質)에 미치는 영향(影響)을 산도수준(酸度水準)에 따라 평가(評價)하였다. 잣나무 종자(種子)를 1985년(年) 봄에 묘포토양(苗圃土壤)을 채운 pot에 파종(播種)하고, 해당지역(該當地域)의 30년간(年間)의 강우양식(降雨樣式)에 모의(模擬)(simulation)해서, 황산(黃酸)과 질산(窒酸)의 비율(比率)을 3:2로 혼합(混合)하여 지하수(地下水)로 희석(稀釋)한 pH 4.0 및 pH 2.0의 산성우(酸性雨)와 지하수(地下水)(pH 6.5)를 5월(月)부터 8월(月)까지 4개월간(個月間)에 걸쳐 살포(撒布)하고, 동년(同年) 10월(月) 30일(日) 시료(試料)를 채취(採取)하여 분석(分析)한 결과(結果)는 다음과 같았다; 1) 잣나무 파종묘(播種苗)의 엽내함유성분(葉內含有成分)의 함량(含量)은 산성우(酸性雨)의 pH 값이 저하(低下)됨에 따라 S와 $K_2O$는 증가(增加)를, MgO 와 $P_2O_5$는 감소(減少)되었다. 2) 산성우(酸性雨)의 pH 값이 낮아짐에 따라 토양산도(土壤酸度)는 저하(低下)되었고, 치환성(置換性) Al 함량(含量)은 크게 증가(增加)하는 상반(相反)된 반응(反應)을 보였다. 3) 토양(土壤)의 치환성(置換性) Ca, Mg 및 K의 함량(含量)과 염기총량(鹽基總量), 염기포화도(鹽基飽和度)는 산성우(酸性雨)의 pH 값이 낮아짐에 따라 현저(顯著)하게 감소(減少)되었다. 4) 토양내(土壤內) sulfate 함량(含量)은 산성우(酸性雨)의 pH 값이 저하(低下) 될수록 크게 증가(增加)하였다.

• 한국환경농학회지
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• 제32권2호
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• pp.102-107
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• 2013

BACKGROUND: Pithy pear fruit are not distinguished externally from sound fruit and thus often cause unexpected economic losses. To find out the cause of pithiness, the pithiness incidence and characteristics of Japanese pear (Pyrus pyrifolia cv. Niitaka) fruit picked from a spot frequently produced pithy fruit in an orchard were compared with those of fruit picked from another spot produced sound fruit every year. And the soil chemical properties of the two spots and mineral contents in fruit, shoots, and leaves of Japanese pear trees cultivated in the two spots were also examined. METHODS AND RESULTS: The pithiness incidence was 0, 8.8, and 11.3% at 7 days before and 0 and 7 days after optimal harvest date, respectively, in the spot frequently produced pithy fruit. Flesh firmness was significantly lower in pithy fruit than in sound fruit, while soluble solids content was slightly higher in pithy fruit than in sound fruit. Unlike other mineral contents, Ca content was significantly lower in pithy fruit than in sound fruit. These results indicate that Ca deficiency in fruit is closely associated with decrease in flesh firmness and thus pithiness development. Ca content in soil of the spot frequently produced pithy fruit was also significantly lower than that in soil of the spot produced sound fruit. However, shoots or leaves did not exhibit significant difference in Ca and/or other mineral contents between the two spots, indicating that Ca deficiency in fruit is dependent on the translocation of Ca within a plant rather than soil Ca status. Although total-N, available $P_2O_5$, K, and Ca contents were significantly lower in soil of the spot frequently produced pithy fruit than in soil of the spot produced sound fruit, Mg and Na contents and pH were not different between the soil conditions. CONCLUSION(S): Fruit maturity and Ca level in fruit are closely related to the incidence of pithiness in 'Niitaka' Japanese pear.

• Journal of Ginseng Research
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• 제13권1호
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• pp.84-91
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• 1989

인삼재배산지에서 연근별 토양이화학성과 이삼생육변화를 조사하여 토성별 생육특성을 파악하고 6년근 수량과 결주율에 미치는 토양이화학성의 영향을 구명코저하였다. 1. 산지 6년근 수량은 토성별고 사양토 1.44, 양토 2.13, 식양토 2.46kg/3.3$m^2$이었다. 2. 6년근 결주율은 사양토 51.6%, 식양토 33.6%이었고 묘직경은 3년근부터 사양토가 식양토보다 적었다. 3. 토양입단율과 공극율은 2년근 때보다 6년근에서 증가하였다. 4. 토양무기태질소는 2, 3년근에서 100-120ppm으로 현저히 증가하였다가 4년근 75ppm, 5년근 34ppm, 6년근 25ppm으로 감소하였으며 사양토에서 감소폭이 컸다. 5. 본 포에서 $P_2O_5$, K, Ca, Mg는 연차간변화가 적었고 토성별로는 사양토가 N, P 함량은 높았고 양이온 함량은 낮았다. 6. 6년근 수량은 점토, 공극율, 수분과 유의성있는 정상관이었고 결주율은 모래, N 함량과 정상관이었다.

• 한국토양비료학회지
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• 제37권6호
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• pp.371-377
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• 2004

산림토양에서의 황산이온 흡착은 식물의 흡수, 양이온 이동 및 산중화능 등 산림생태계의 황 동태에 중요한 영향을 미친다. 따라서 본 연구는 산림토양 중의황산이온 분포와 그와 관련된 황산이온 흡착이 어떠한 토양특성에 의해 영향을 받는지를 밝히기 위해 수행되었다. 이를 위해 소나무와 신갈나무 임분으로 조성된 4개 산림지역을 대상으로 표토층과 심토층으로 구분하여 황산이온 흡착지표로서의 추출성 황산이온함량 및 황산이온 흡착능을 정량 한 후 관련 토양 물리화학적 특성인 pH. 양이온치환용량, 점토함량 및 Ai과 Fe 산화물의 종류별 함량과의 상관성을 분석하였다. 토양 중 추출성 황산이온 함량 및 황산이온 흡착능은 각 조사지별로 큰 차이를 보였으며 전체적으로 유기물 함량이 적고 Al 또는 Fe 산화물 함량은 많은 심토층이 표토층에 비하여 황산이온 흡착량이 많았다. 황산이온 흡착량이 많았던 심토층의$Al_d$와 $Fe_d$ 산화물 평균 함량은 각각 8.49와 $12.45g\;kg^{-1}$로 대체로 낮은 수준이었다. 황산이온 흡착지표들은 토양 pH, 양이온치환용량 및 점토함량과 대체로 유의적인 정의 상관관계를 보였다. 반면에 유기탄소 함량과는 부의 상관성을 보여 산림토양 중에서 유기물이 황산이온 흡착에 대해 경합물질로 작용함을 알 수 있었다. Ai과 Fe 산화물 중에서는 $Al_d,\;Al_o,\;Al_p,\;Al_a$ 및 $Fe_a$가 황산이온 흡착지표들과 유의성 있는 상관성을 보였으나, $Al_c$와 $Fe_c$는 황산이온 흡착지표들과 상관성이 없었다. 황산이온 흡착지표인자들과 토양 pH, 양이온치환용량 및 비결정형 Ai 함량간의 정의 상관관계 결과는 토양산성화로 인해 산림생태계에서 황 동태에 기여하는 산림토양의 황산이온 흡착 능력이 저하될 수 있음을 반영한다.

• 한국토양비료학회지
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• 제48권3호
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• pp.170-179
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• 2015

This study was carried out to investigate the sustainable agriculture of no-tillage technique to minimize tillage problems under rain interception green house condition including recycling of the ridge and the furrow for following cultivation in Korea. Chemical properties in soils were investigated at 3-years after cultivation at conventional tillage [CT; 2-years no-tillage (2009-2010) and 1-year (2011) tillage] and no-tillage [NT; 2009-2011] field. Soil pH maintained between 5.8 and 6.0 irrespectively tillage and no-tillage. Salinity (EC), contents of total nitrogen (TN), cation exchange capacity (CEC), and exchangeable cations (K, Ca and Mg) in soil were remarkably higher in CT than in NT treatment. Salinity (EC), contents of OM, TN, CEC, and exchangeable cations in top soil and subsoil indicated higher deviation in CT than NT treatment. Organic matters and inorganic matters in soil were positive (+) correlation. Suppression of pepper growth and increase of yield were observed in no-tillage soil compared with tillage soil. These results indicated that no-tillage technique in crop culture could play an important role with respect to chemical properties in silt loam soil.

• Journal of Plant Biology
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• 제12권4호
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• pp.9-18
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• 1969

In the previous paper(part III), a certian relationships between the changes of chlorinity and organic acid released from organic material were seemed to be concened to each other in saline soil suspension. Such a possibility had been a cause to take this experiments and this experiment was carried out under the treatment of organic acid crystal, oxalic acid and succinic acid, to the soil suspension(soil: water=20g:40cc) directly. The amount of organic acid treated to the suspension were related to the contents of organic material, as amount of organic acid per gram of organic material(391.76mg). The saline soil suspension were grouped and treated with the acids in order of 78.35mg(Group 1), 391.76mg(Group 2) 979.4mg(Group 3), and 1958.8mg(Group 4), respectively. Treated suspension had been incubated at room temperature and extract from suspension was used for analysis. Followings are summary of this report. 1) Changes of pH in soil suspension appeared a little increase after the treatment of organic acid until 168 hours. 2) Total acidity of soil suspension showed a variation, however, the values of total acidity appeared not to be increased or decreased during the period of experiment. 3) Sugar contents of soil suspension was increased until 168 hours after treatment. These results are similar tendency to the previous paper. 4) Addition of organic acid to soil suspension was confirmed not to be effective method for desalination from saline soil. Chlorinity of group 3 and 4 which were treated with high concentration of organic acid showed a decrease comparing to control group.

• The Korean Journal of Ecology
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• 제21권5_3호
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• pp.695-702
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• 1998

This study was carried out to investigate to determine seasonal variation of dehydrogenase activity, phosphatase activity, adenosine tri-phosphate content and some physicochemical properties, such as soil pH, moisture content, organic matter and several heavy metal concentrations from Apr. 1997 to jan. 1998 in Pinus densiflora and Quercus mongolica forest in Mt. Nam, to explain a relationship between enzyme activity and the soil factors. There were ranges of 4.03-4.65 in soil pH, 18.65-51.09% in moisture content and 6.69-95.95% in orgainc matter. The organic matter content decreased with soil horizon, showing the higher values in Q. mongolica forest. In comparison to the results of Kawngneung site as control area, there were slightly differences due to a development level of forest ecosystem and microbial degradation of organic matter. The heavy metal concentrations showed 32.50-75.55 ${\mu}g/g$ in Cu, 69.33-134.84 ${\mu}g/g$ in Zn, 57.02-150.32 ${\mu}g/g$ in Pb, and 0.36-1.00 ${\mu}g/g$ in Mt. Nam. These values are higher than in Kwangneung site because of long-term exposure to air pollutants from central city. On the other hand, ATP contents in Mt. Nam were lower than in Kawngneung site in relation to soil organic matter, moisture content and relatively high heavy metal concentrations. ATP contents per soil weight was largest in F+H layer and in spring time of other seasons. Dehydrogenase activity as an index of soil microbial activity had a ranges of 170.67-1,221.66 ${\mu}g$ TPF/g that showed lower values than in Kawngneung site. However, phophatase activity had a contray tendency due to P fertilization for a continuous management. Those values increased through spring to a maximum in the summer and fall in autumn. This is basically caused by metabolic state of soil on the biological activity and several and several factors, such as aeration, soil temperature, vegetation and microflora.

• 한국토양비료학회지
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• 제33권2호
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• pp.79-84
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• 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.