연구논문 : 자연과학 ; 우간다 농경지의 토양비옥도

조창현 ( Chang Hyon Jo ) 한국국제농업개발학회 2012 韓國國際農業開發學會誌 Vol.24 No.1

This study was conducted to investigate the soil fertility and nutrient balances of smallscale farming systems, and its relation to alleviation of rural poverty of Uganda. Data from the observations of the small-scale farming systems and from the literatures concerning the soil fertility and rural poverty of Uganda were analyzed. Tested soils of arable land showed a low values of soil pH and soil fertility. Especially, contents of phosphorus in soil were very low. When the nutrient balances were estimated for small-scale farming systems and several crop monocultures, they showed a negative values for macro elements (nitrogen, phosphorus, and potassium) in all small-scale farming systems except some banana-based arable lands. Especially, higher negative values of the nutrient balances were obtained at maize and soybean monocultures than other crops, which may be due to the fact that those were grown under deficient contents of nitrogen and phosphorus. Based on the results from analysis of soil fertility, the cause of existing rural poverty of Uganda can be explained as following flows in the viewpoint of soil characteristics; soil erosion and insufficient soil nutrient management cause nutrient losses in soil (low soil fertility). Low soil fertility, or nutrient deficiency in soil, results in low crop productivity per area, which, in turn, increases rural poverty. Improved soil pH and soil fertility of arable land is the most important factor for maintenance and increase of the soil productivity, and it may contribute to alleviation of the existing rural poverty in Uganda.

Fertility Status in Northeastern Alpine Soils of South Korea with Cultivation of Vegetable Crops

양재의,조병옥,신영오,김정제,Yang, Jae-E.,Cho, Byong-Ok,Shin, Young-Oh,Kim, Jeong-Je 한국토양비료학회 2001 한국토양비료학회지 Vol.34 No.1

Total upland area for cultivating the vegetable crops in the Alpine soils of Northeastern South Korea has been extending its limit to meet the increasing demand of vegetable food in recent decades. About 70% of these alpine soils are located in over 7% of the slope and most of vegetable crops have been cultivated intensively without practicing the best management systems. Thus, soil erosion and continuous cropping system have degenerated the soil fertility and shown detrimental effects on water quality. We initiated an intensive and extensive investigation to characterize the fertility problems encountered in these uplands. Objectives of this paper were to characterize the fertility status in the Alpine soils cultivated with vegetable crops for many years and to provide the recommendations for adequate soil management measures including fertilization and erosion control. Soils in general have good drainage with textural classes of loam or sandy loam. Their topographical characteristics tended to lead them to shallow plow layers, and the steepness of the terrain created erosion hazard. Of the soils examined, about 11% of uplands over 30% gradient was found in need of an urgent reforestation. A high content of gravel and firm hardness of soil attributed to inhibit the utilization of farm machinery and plant-root development. The average soil pH 5.6 was slightly low relative to pH 5.70 of the national average. Organic matter content was high compared with 2.0% of national average, but decreased with the prolonged cultivation periods. Available $P_2O_5$ concentration was unusually high due to the consequence of over dose application with chemical and organic fertilizers. Exchangeable cations as Ca, Mg, and K were appeared to be decreased in these regions with prolonging the cultivation periods. There were no significant differences in cation exchange capacity (CEC) and electrical conductivity (EC) among locations. Heavy metal contents were mostly lower than the threshold of danger level designated by Soil Environment Conservation Law of South Korea. Results indicated that a proper countermeasure and the best management practice should be immediately implemented to conserve the top soil and fertility in the Alpine regions. 지난 2, 30년 동안에 진행되고 있는 한국인의 식생활변화와 함께 채소 작물에 대한 수요가 급격히 증가하면서 강원도 고랭지 토양이 여름 채소 재배지로 각광을 받게 되었고 그 재배 면적이 매년 확대 일로에 있다. 이 토양의 비옥도를 유지 내지는 향상시키고 적절한 관리를 기하기 위해 광범위하고 집중적인 조사와 검정을 실시하여 얻은 결과의 일부를 다음과 같이 정리할 수 있었다. 조사된 토양은 일반적으로 양토 내지는 사양토로써 배수가 양호하였으며 대부분 경사지에 놓여 있기 때문에 심할 경우 침식의 위험에 노출되게 되어 경작충이 매우 얕았으며, 이 중 30% 또는 그 이상의 경사도를 가진 토양 11%는 곧 다시 조림해야 할 정도로 농경지로써는 부적절하였다. 이미 받은 침식으로 인해 자갈 함량이 높았으며 토양의 경도 역시 식물의 뿌리 신장과 농기구 사용에 지장을 줄 정도였다. 토양의 pH는 산성화 쪽으로 진행되었고, 유기물 함량, 치환성 염기인 Ca, Mg, 그리고 K의 함량은 경작 연수가 증가함에 따라 감소하였는데 유효 인산 ($P_2O_5$)만은 농가의 퇴구비 과다 사용 결과로 인해 크게 증가하는 경향을 보였다. 양이온 치환용량(CEC)과 전기 전도도(EC)는 토양과 토양 사이에 별 차이가 없었다. 이 지역의 고랭지 토양은 아직 Cd, Cu, Pb, Zn 그리고 Ni등의 중금속 원소에 의한 토양 오염의 영향을 받지 않은 것으로 나타났다.

조사료-벼 작부체계에서 토양유기탄소와 비옥도 비교

윤순강 ( Sun-gang Yun ),이창훈 ( Chang Hoon Lee ),고병구 ( Byong-gu Ko ),박성진 ( Seong-jin Park ),김명숙 ( Myung-sook Kim ) 한국환경농학회 2016 한국환경농학회 학술대회집 Vol.2016 No.-

Soil organic carbon plays a important roles on soil fertility and crop yields. There is little information on the carbon storage under forage cultivation at winter season in rice paddy. In this study, we evaluated the soil organic carbon and soil fertility in paddy cultivated Italian-ryegrass(IRG), barely, and rye as animal feedstock at winter season. Soil organic carbon concentration was ordered to 17.4, 13.6, 14.3 g C kg-1 at IRG, barely, and ryegrass cultivation, respectively. Especially, soil organic carbon in the field cultivated IRG was 19.5% higher than in the mono-rice cultivation. All of bulk density in soil was ranged from 1.17 to 1.30 g cm-3 irrespective of cropping systems and was correlated strongly negative to the soil organic carbon. Carbon storage in IRG fields was average 30.1 Mg ha-1 at 15 cm of soil depth and was 20.4 and 10.3% higher than those of barely and rye fields, respectively. Increasing carbon storage was improved soil fertility for next crop cultivation. This result indicated that Italian-ryegrass cultivation at winter season could be a alternative to improve soil organic carbon and fertility of paddy soil.

Fertilizer NPK Recommendations for Kiwi Cultivation Based on Soil Testing in Jeju

Ho-Jun Kang 한국토양비료학회 2019 한국토양비료학회지 Vol.52 No.1

This study was carried out in order to determine the Kiwi fruit (Actinidia deliciosa cv. Hayward) fertilization standards in Jeju. Soil chemical properties and mineral contents of leaves, and the amounts of fertilizers were investigated in 35 places of volcanic ash soils and in 15 places of non volcanic ash soils. Tests were made to provide the most resonable fertilizer recommendation for kiwi fruit based on soil analytical data and leaf mineral contents response to the NPK fertilizers. Average pH was 6.0, organic matter (OM) content was 113 g kg<SUP>-1</SUP>, available P₂O5 content was 288 mg kg<SUP>-1</SUP>, and exchangeable K, Ca, and Mg were 1.61, 10.5, and 3.1 cmolc kg<SUP>-1</SUP>, respectively for volcanic ash soils. Also, Average pH was 5.7, organic matter (OM) content was 48.3 g kg<SUP>-1</SUP>, available P₂O5 content was 541 mg kg<SUP>-1</SUP>, and exchangeable K, Ca, and Mg were 1.45, 6.6, and 2.2 cmolc kg<SUP>-1</SUP>, respectively for non volcanic ash soils in Jeju. Available phosphorus contents of volcanic ash soils, were lower than those of non volcanic ash soils. However, soil organic matter contents were higher than those of the optimun range. P and Mg contents of kiwi fruit leves were lower in comparison with a suitable standard leaf, but K and Ca contents were higher. The amounts of N, P₂O5, and K₂O fertilizers applied to farmers` fields were N 22.4 kg 10a<SUP>-1</SUP>, P₂O5 21.6 kg 10a<SUP>-1</SUP>, and K₂O 18.3 kg 10a<SUP>-1</SUP> in volcanic ash soils. Those of non volcanic ash soils were 17.1 kg 10a<SUP>-1</SUP>, 13.5 kg 10a<SUP>-1</SUP> and 13.3 kg 10a<SUP>-1</SUP>. The Yield had no difference between the volcanic ash soils and non volcanic ash soils. The relationship between soil chemical properties and amounts of fertilizer use were observed. The soil organic matter contents werenegatively correlated with amounts of nitrogen fertilizers. Soil available phosphorus contents were negatively correlated with amounts of phosphate fertilizer. Also, Soil exchangeable potassium contents showed negative correlation with amount of potassium fertilizer. Recommended fertilizer amounts for N and P₂O5 were determined by using the soil OM and available P₂O5 contents. Recommended K₂O fertilizer were determined by exchangeable K contents in soils. Amounts of standard fertilization N-P₂O5-K₂O fertilizer in volcanic ash soils were 16.5-16.5-11.1 kg/10a for kiwi fruit of 8 years or older, and 13.5-8.8-9.0 kg/10a in non volcanic ash soils.

Fertilizer NPK Recommendations for Kiwi Cultivation Based on Soil Testing in Jeju

강호준 한국토양비료학회 2019 한국토양비료학회지 Vol.52 No.1

This study was carried out in order to determine the Kiwi fruit (Actinidia deliciosa cv. Hayward) fertilizationstandards in Jeju. Soil chemical properties and mineral contents of leaves, and the amounts of fertilizers wereinvestigated in 35 places of volcanic ash soils and in 15 places of non volcanic ash soils. Tests were made toprovide the most resonable fertilizer recommendation for kiwi fruit based on soil analytical data and leafmineral contents response to the NPK fertilizers. Average pH was 6.0, organic matter (OM) content was 113 gkg-1, available P2O5 content was 288 mg kg-1, and exchangeable K, Ca, and Mg were 1.61, 10.5, and 3.1 cmolckg-1, respectively for volcanic ash soils. Also, Average pH was 5.7, organic matter (OM) content was 48.3 gkg-1, available P2O5 content was 541 mg kg-1, and exchangeable K, Ca, and Mg were 1.45, 6.6, and 2.2 cmolckg-1, respectively for non volcanic ash soils in Jeju. Available phosphorus contents of volcanic ash soils, werelower than those of non volcanic ash soils. However, soil organic matter contents were higher than those of theoptimun range. P and Mg contents of kiwi fruit leves were lower in comparison with a suitable standard leaf,but K and Ca contents were higher. The amounts of N, P2O5, and K2O fertilizers applied to farmers' fields wereN 22.4 kg 10a-1, P2O5 21.6 kg 10a-1, and K2O 18.3 kg 10a-1 in volcanic ash soils. Those of non volcanic ashsoils were 17.1 kg 10a-1, 13.5 kg 10a-1 and 13.3 kg 10a-1. The Yield had no difference between the volcanic ashsoils and non volcanic ash soils. The relationship between soil chemical properties and amounts of fertilizeruse were observed. The soil organic matter contents werenegatively correlated with amounts of nitrogenfertilizers. Soil available phosphorus contents were negatively correlated with amounts of phosphatefertilizer. Also, Soil exchangeable potassium contents showed negative correlation with amount of potassiumfertilizer. Recommended fertilizer amounts for N and P2O5 were determined by using the soil OM andavailable P2O5 contents. Recommended K2O fertilizer were determined by exchangeable K contents in soils. Amounts of standard fertilization N-P2O5-K2O fertilizer in volcanic ash soils were 16.5-16.5-11.1 kg/10a forkiwi fruit of 8 years or older, and 13.5-8.8-9.0 kg/10a in non volcanic ash soils.

우간다 농경지의 토양비옥도

이주삼,가학현,이수철,김장생,조창현 한국국제농업개발학회 2012 韓國國際農業開發學會誌 Vol.24 No.1

본 연구는 우간다 농경지의 토양비옥도와 소규모 영농형태에서의 양분균형을 검토하여, 농촌빈곤의 원인을 파악하고 그 해결방안을 제시하고자 하였다. 우간다 농촌의 소규모 농가의 현장조사 자료 및 관련 문헌의 연구결과를 인용하였다. 1. 우간다의 농경지 토양은 강산성이었고, 비옥도는 낮았다. 특히 인산함량이 낮았다. 2. 농경지의 양분균형은 모든 영농형태와 일부 바나나 단작을 제외한 기타 재배작물의 단작에서 양분부족을 나타내었다. 3. 현재의 우간다 농촌 빈곤율을 토양비옥도 측면에서 다음과 같이 설명할 수 있다. 즉, 토양침식 및 부적절한 토양 양분관리 → 양분유실 → 토양비옥도 저하 → 양분부족 → 작물생산성 저하 → 빈곤 율 증가로 나타낼 수 있다. 4. 농경지의 비옥도 개선은 토양생산성 유지와 향상에 중요한 요인이며, 농촌 빈곤을 감소시키는데 기여한다. This study was conducted to investigate the soil fertility and nutrient balances of smallscale farming systems, and its relation to alleviation of rural poverty of Uganda. Data from the observations of the small-scale farming systems and from the literatures concerning the soil fertility and rural poverty of Uganda were analyzed. Tested soils of arable land showed a low values of soil pH and soil fertility. Especially, contents of phosphorus in soil were very low. When the nutrient balances were estimated for small-scale farming systems and several crop monocultures, they showed a negative values for macro elements (nitrogen, phosphorus, and potassium) in all small-scale farming systems except some banana-based arable lands. Especially, higher negative values of the nutrient balances were obtained at maize and soybean monocultures than other crops, which may be due to the fact that those were grown under deficient contents of nitrogen and phosphorus. Based on the results from analysis of soil fertility, the cause of existing rural poverty of Uganda can be explained as following flows in the viewpoint of soil characteristics; soil erosion and insufficient soil nutrient management cause nutrient losses in soil (low soil fertility). Low soil fertility, or nutrient deficiency in soil, results in low crop productivity per area, which, in turn, increases rural poverty. Improved soil pH and soil fertility of arable land is the most important factor for maintenance and increase of the soil productivity, and it may contribute to alleviation of the existing rural poverty in Uganda.

Soil Conditioning Effects to Soil Microbe Density and Crop Growth by Vermi-cast and Liquid Fertilizer

( Ki-wan Lee ),( Woo-jung Kim ) 한국환경기술학회 2019 한국환경기술학회지 Vol.20 No.5

It is known that organic sludge is generated in large quantities due to the need for proper treatment of waste, and that it is very difficult to treat and recycle. In this research, vermi-cast and liquid fertilizer, which are soil conditioners, were produced using organic waste as raw materials in order to utilize organic waste. Two kinds of the soil conditioners produced were treated with cucumber, tomato on vermi-cast and liquid fertilizer, and the growth experiment and soil microbe density survey were conducted. In the case of liquid fertilizer, a dilution concentration of 500 to 1000 times was appropriate for cucumber crops. Leaf length and leaf width improved by about 16 %. The growth of tomato crops was not much different. Plant growth promoting rhizobacteria showed a high density distribution about 500 to 1,000 times in the soil of the liquid fertilizer treatment area , and about twice as high in the area of dilution that. As a result of the density survey of pathogenic microorganisms, it was found that pathogenic E. coli and Salmonella do not affect the soil. Also, there was almost no difference in growth between untreated control port and treatment port in cucumber crops. During vermi-cast treatment, the density change of plant growth promoting rhizobacteria in the soil showed a high density distribution of about 2 to 5 times or more from 600 ∼ 1,000 kg/1000 ㎡ treated soils. Also, pathogenic E. coli and Salmonella were found not to affect the soil. The organic waste fertilizer treatment of vermi-cast and liquid fertilizer is judged to have sufficient value as an advanced fertilizer by increasing the density of microorganisms in the soil more than twice.

토양의 정량적 및 정성적 특성을 이용한 연초 경작지의 비옥도 평가

홍순달,김기인,이윤환,정훈채,김용연 한국연초학회 2000 한국연초학회지 Vol.22 No.2

Evaluation method of soil fertility by combination of soil color characteristics and survey data from soil map as well as chemical properties was investigated on total 35 field and pot experiments. Total 35 tobacco fields including 11 fields located at Cheonweon county in Chungnam Province, 9 fields located at Goesan county in Chungbuk Province, and 15 fields located at Youngcheon county in Kyongbuk Province were selected in 1984 to cover the wide range of distribution in landscape and soil attributes. Yields of tobacco grown on the plots of both the pot and field experiment which were not applied with any fertilizer were considered as basic fertility of the soil (BFS). The BFS was estimated by 32 independent variables including 15 chemical properties, 3 color characteristics, and 14 soil survey data from soil map. Twenty-four independent variables containing 16 quantitative variables selected from 24 quantitative variables by collinearity diagnostics and 8 qualitative variables, were classified and analyzed by multiple linear regression (MLR) of REG and GLM models of SAS. Tobacco yield of field experiment showed high variations by eight times in difference between minimum and maximum yield indicating the diverse soil fertility among the experimental fields. Evaluation for the BFS by the MLR including quantitative variables was still more confidential than that by a single index and that showed more improvement of coefficient of determination ($R^2$) in pot experiment than in field experiment. Evaluation for the BFS by MLR in field experiment was still improved by adding qualitative variables as well as quantitative variables. The variability in the BFS of field experiment was explained 43.2% by quantitative variables and 67.95% by adding both the quantitative and qualitative variables compared with 21.7% by simple regression with NO$_3$-N content in soil. The regression evaluation for the best evaluation of the BFS of field experiment by MLR included NO$_3$-N content, L value, and a value of soil color as quantitative variables and available soil depth and topography as qualitative variables. Consequently, it is assumed that this approach by the MLR including both the quantitative and qualitative variables was available as an evaluation model of soil fertility for tobacco field.

밭 토양에서 규산질비료 시용이 토양 환경에 미치는 영향

주진호 ( J. H. Joo ),이승빈 ( S. B. Lee ) 강원대학교 농업생명과학연구원(구 농업과학연구소) 2011 강원 농업생명환경연구 Vol.23 No.4

Application of silicate fertilizers is typically practiced to amend soil quality and improve rice productivity at the paddy field in Korea, and their effects are well-established. However, a little research on the effect of silicate fertilizers on soil and crop growth in upland soil was reported. Most of silicate fertilizers applied in Korea is slag-originated silicate fertilizer. Some water soluble silicate fertilizers are manufactured and commercially available. The objective of this study was to assess changes of soil chemical properties in potato-grown plots by applying slag-originated silicate fertilizer and water soluble silicate fertilizer. Field experiment was conducted on a silt loam paddy soil, where four levels of each silicate fertilizer were applied in soil at the rate of 0, 1, 2, 4 times of the recommended levels. Application of slag-originated silicate fertilizer increased soil pH, while no significant pH increase was occurred with the treatment of water soluble silicate fertilizers. Soil pH increased proportionally as slag-originated silicate fertilizer was applied. Available SiO2 contents also increased with the treatment of slag-originated silicate fertilizer. Exchangeable Ca, Mg and available phosphate contents in soil increased with application of slag-originated silicate fertilizer, while no significant increases for exchangeable Ca, Mg and available phosphate contents were shown with the application of soluble silicate fertilizer. Throughout this study, soil application of slag-originated silicate fertilizer enhanced soil chemical properties, while water soluble silicate fertilizer application in soil needs further study to better understand application method, application rate, type of water soluble silicate fertilizer, etc.

밭토양에 처리된 규산질 비료의 유효화와 토양반응 교정효과

조현종 ( Hyun Jong Cho ),최희열 ( Hee Youl Choi ),이용우 ( Yong Woo Lee ),이윤정 ( Yoon Jung Lee ),정종배 ( Jong Bae Chung ) 한국환경농학회 2004 한국환경농학회지 Vol.23 No.2

Although silicon (Si) has been known to be an essential element for rice growth, the optimum soil level of Si for upland crops remains unestablished. This study was conducted to estimate the availability of Si fertilizer in upland soils, and also effect of the Si fertilizer on soil pH was examined. Different application rates of Si fertilizer were tested using four soils of different available Si levels and pHs in a series of laboratory incubation study. The treatments included Si fertilizer levels of 100, 200, and 300 kg/10a. Also to examine the effects of compost and lime on the availability of Si fertilizer in upland soil, treatment of silicate fertilizer 200 kg/10a + compost 1,000 kg/10a and lime alone treatment were included. Changes of Si availability in the soils during the incubation period were measured by 1 N NaOAc extraction procedure. Availability of Si fertilizer was different among the tested soils, and about 9.1~19.2% of the applied Si fertilizer was extracted after 60 days laboratory incubation. Application rate could not influence the availability of Si fertilizer. Application of compost with Si fertilizer could not increase Si availability in upland soils, but lime treatment could increase Si availability. Soil pH increased by application of Si fertilizer, but the effect of Si fertilizer on soil pH was minimal. When Si fertilizer is applied on the purpose of Si nutrition in acid upland soils, lime treatment should be coupled with the Si fertilizer for remediation of soil acidity.