• 한국응용곤충학회지
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• 제60권4호
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• pp.417-422
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• 2021

월동기 논과 논두렁에서 서식하고 있는 다양한 절지동물의 발생밀도를 조사하여 생물다양성에 대한 정보를 제공하고자 본 연구를 수행하였다. 동력흡충기를 이용하여 논과 논두렁에서 각각 5지점씩 50×50 cm 격자 내에 있는 지표면과 식물을 흡입하여 채집하였다. 논과 논두렁에서 채집한 총개체수는 41,197개체였으며, 대부분 Collembola, Hemiptera, Diptera가 많이 채집되었다. 영농형태별 유기농법 재배지와 관행농법 재배지에서의 절지동물 출현패턴은 거의 유사하였으나 채집된 개체수는 유기농법 재배지에서 더 많았다. 종다양성지수, 종풍부도지수, 종균일도 지수는 논보다는 논두렁에서 모두 높게 나타났고, 시기별로 큰 차이를 보였는데 이는 통계적으로 유의하였다(P < 0.05).

• 한국작물학회지
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• 제51권1호
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• pp.48-52
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• 2006

Naturally occurring soybean isoflavones are known to be influenced by various genetic and environmental conditions. Growth, yield, and isoflavone content were determined in four different cultivars of soybean grown under drained paddy and upland fields. Most of growth characteristics and yield components of four different soybean cultivars harvested in drained paddy field were greater than those in upland field, regardless of cultivar. By means of high performance liquid chromatography, total daidzein and genistein contents of soybean in drained paddy field were increased up to 40 and 35%, respectively, compared with those in drained paddy field. Besides isoflavone contents, the growth and yield of soybean were significantly affected by cultivar and field conditions, indicating the necessity of genetic program for soybean cultivars appropriate to drained paddy field conditions. In conclusion, converting paddy field into upland may effectively improve soybean cropping system, especially in terms of isoflavone increment under paddy field conditions.

• 한국물환경학회지
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• 제20권6호
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• pp.597-602
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• 2004

Field experimental study was performed to examine characteristics of nutrient export from paddy rice fields with irrigation practices. Experimental fields with surface-water and ground-water irrigation were monitored and analyzed during rice culture period. The water balance showed that outflow generally balanced the inflow showing that about half (58~68%) of total outflow was lost by surface drainage. Water and nutrient export are more in surface-water irrigation paddy than in ground-water irrigation paddy. The reasons might be more irrigation water available and easy to use in surface-water irrigation. If irrigation water reduced, it could result in reduction of nutrient export in paddy rice fields, which can save water and protect water quality. However, deviation from conventional standard practices might affect the rice yield and further investigations are necessary.

• 농촌지도와개발
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• 제27권2호
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• pp.75-87
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• 2020

The purpose of this study is to investigate the location characteristics of the rice paddy fields and to predict shrinking areas of them. The study area is in South Korea nationwide, and a 300×300m raster level is adopted as a spatial analysis unit. The binary logit model and spatial simulation model are employed for the analyses. As a result, population, industry, climate and nature, and accessibility play a significant role in determining rice paddy fields' locations. It is predicted that the shrinking rate will be high in Gangwon-do, Gyeongsangbuk-do, and Gyeongsangnam-do until 2027. The hot spots are intensively shaped in the inland of Gangwon-do, eastern parts of Gyeonggi-do, and the borders of Gyeongsangnam-do and Jeollabuk-do between Charyeong and Sobaek mountain ranges. Using Gimcheon-si as an example, the study suggests fundamental policy implications for taking advantage of the simulation results from the lens of local agriculture. Several policy measures are proposed for improving management strategies for the rice paddy fields in the long run.

• 한국환경농학회지
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• 제17권3호
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• pp.211-214
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• 1998

휴경답에서의 휴경년한에 따른 토양의 이화학적 특성과 주요 영양분의 변화 및 잡초종의 식생 변화를 조사하였다. 휴경년한이 경과할수록 휴경답 토양의 유기물 함량이 증가하였으며 pH는 휴경후 3년까지는 변화가 없었으나 이후로는 다소 증가하였다. 토양의 양이온치환용량 및 치환성 N, K, Ca, Mg의 함량은 휴경후 3년까지는 감소하였으나 휴경년한이 길어지면서 증가하였다. 유효 $P_2O_5$의 함량은 휴경년한이 길어지면서 지속적으로 감소한 반면 유효 $SiO_2$의 함량은 3년까지는 변화가 없었으나 그이후로는 증가하였다. 휴경답에서의 잡초종 구성은 초기에는 화본과, 사초과 및 국화과가 주종을 이루었으며 휴경년한이 경과할수록 마디풀과와 골풀과의 잡초 발생이 증가하는 반면 콩과, 물옥잠과, 닭의장풀과, 바늘꽃과의 잡초 발생이 점차 감소하였다. 그러나 화본과의 사초과의 잡초종은 휴경년한의 경과와는 관계없이 항상 우점종으로 발생하였다. 일반적으로 휴경화가 진전될수록 일년생 잡초종에 비해 다년생 잡초종의 발생 비율이, 또한 논 잡초종에 비해 밭 잡초종의 발생 비율이 높아지는 경향이 뚜렷하였다.

• Water Engineering Research
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• 제4권4호
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• pp.193-202
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• 2003

SWAT model was applied to estimate daily stream flow for Yongdam and Bocheong watersheds in Korea. The model was calibrated and validated for the two watersheds and a new routine was added to analyze runoff process in paddy fields. The model efficiencies for two watersheds were 0.77 and 0.65 for the calibration period, and 0.76 and 0.50 for the validation period, respectively. It showed that water balance method simulated the runoff from paddy fields more precisely than CN method in SWAT. As results, the SWAT model is applicable to Korean watersheds, and more accurate estimation is possible using daily water balance method in paddy fields.

• 한국농공학회논문집
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• 제53권4호
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• pp.59-65
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• 2011

The purpose of this study was to analyze the water quality change when wastewater applied to study paddy fields. CREAMS-PADDY (Chemical, Runoff and Erosion from Agricultural Management System) model was used to estimate the field-scale water quality. Simulated results were compared with observed data monitored from Byeongjeom study paddy fields which is located near the Suwon sewage treatment plant in Gyeonggi-do. Significance analysis was performed for the three different irrigation water quality level and five fertilizer reduction scenarios using LSD (Least Significant Difference) and DMRT (Duncan's Multiple Range Test). Total nitrogen was found to be significant for both irrigation water quality level and fertilizer reduction while total phosphorus was not. Annual drainage load for total nitrogen was reduced by 66~92 % compared to irrigation load when treated wastewater irrigated to study paddy fields from 2002 to 2007. Total phosphorus was reduced by 70~86 %.

• 한국농공학회논문집
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• 제63권4호
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• pp.55-64
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• 2021

The expansion of upland crop cultivation in rice paddy fields is recommended by the Korean government to solve the problem of falling rice price and reduction of rice farmer's income due to oversupply of rice. However, water use efficiency is significantly influenced by the land use change from paddy field to upland. Therefore, this study aimed to evaluate the water budget of soybean grown in using APEX (Agricultural Policy and Environmental eXtender) model. The amount of runoff was measured in a test bed located in Iksan, Jeollabu-do and used to calibrate and validate the simulated runoff by APEX model. From 2019 to 2020, the water budget of soybean grown in uplands were estimated and compared with the one grown in paddy fields. The calibration result of AP EX model for runoff showed that R² (Coefficient of determination) and NSE (Nash-Sutcliffe efficiency) were 0.90 and 0.89, respectively. In addition, the validated results of R² and NSE were 0.81 and 0.62, respectively. The comparative study of each component in water budget showed that the amounts of evapotranspiration and percolation estimated by APEX model were 549.1 mm and 375.8mm, respectively. The direct runoff amount from upland was 390.1 mm, which was less than that from paddy fields. The average amount of irrigation water was 28.7 mm, which was very small compared to the one from paddy fields.

• 한국전통조경학회지
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• 제41권1호
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• pp.1-9
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• 2023

본 연구는 청산도 구들장논 석축을 대상으로 관속식물 특성을 파악하여 향후 청산도 구들장논 석축의 식물다양성 보존 및 관리를 위한 기초자료로 수행되었다. 청산도 구들장논 석축의 전체 관속식물은 60과 142속 170종 5아종 9변종 총 184분류군으로 확인되었다. 희귀식물은 1분류군, 한국특산식물은 2분류군, 식물구계학적 특정식물은 28분류군, 암벽식생은 20분류군, 침입외래식물은 25분류군이었다. 이 중 희귀식물인 고란초는 부흥리, 청계리 구들장논 석축에서 소수 개체로 확인되었으나 구들장논 석축 훼손, 방치로 인해 종·개체수 감소가 우려되므로 생육지 보존이 필요하다.

• 한국토양비료학회지
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• 제49권6호
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• pp.655-661
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• 2016

Relationships between saturated conductivity (Ks) and separate contents were evaluated from 44 soil series of arable lands: 18 for paddy fields and 26 for upland crop fields. Saturated hydraulic conductivities of A, B, and C horizons were determined with tension infiltrometer and Guelph permeameter in situ. Sand, silt, clay, and organic matter content of each horizon were analyzed. Based on correlation analysis, sand separate had a positive relationship with Ks for both paddy (r=0.27, p=0.017) and upland fields (r=0.24. p=0.030). Clay content had a negative relationship with Ks for paddy soils (r=-0.32, p=0.005) while significant correlation between them was not found for upland crop fields (r=-0.20, p=0.07). Organic matter content showed a positive relationship with Ks only for upland crop fields (r=0.33, p=0.002). Due to low correlation coefficients between separate contents and Ks, performance of pedotransfer functions was not enough to estimate Ks. It implies that hydraulic properties of arable lands were affected by other factors rather than particle characteristics. Platy structure and plow pan were suggested to limit Ks of paddy fields. Soil compaction and diversity of parent materials were proposed to influence Ks of upland crop fields. It suggests that genetic processes and artificial managements should be included in pedotransfer functions to estimate hydraulic properties appropriately.