• 한국작물학회지
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• 제54권2호
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• pp.192-197
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• 2009

지구온난화 등에 따른 세계적 환경변화에 대응하고 정부의 친환경 농업육성 정책에 부응하는 정밀농업기술 중 GPS를 이용한 이앙과 동시 변량시비가 벼 생육 및 품질에 미치는 영향을 구명한 결과는 다음과 같다. 1. 시험전 후 토양 질소검정량에 대한 공간변이 정도를 나타내는 Nugget값은 관행 대비 변량시비 후 낮아졌고, 공간구조 강도를 나타내는 Q값은 두 처리 모두 없어 공간의 존성이 존재하지 않았다. 2. 분얼기부터 성숙기까지 초장, 경수, 수수 등의 생육량은 관행 대비 변량시비에서 증가되었고 생육 요인별 변이계수가 낮아 상대적으로 균일한 경향을 보였다. 3. 완전미 수량은 관행 450 kg 대비 변량시비에서 492 kg으로 유의성 있게 증가 되었고 변이계수는 현저히 낮아졌다. 4. 아밀로스, 단백질 함량, 백도 등 품질은 처리간 큰 차이가 없었으나 변이계수는 변량시비에서 낮아졌다. 5. 비료살포작업에 대한 투입노동력은 관행 11.8시간/ha 대비 변량시비에서 61%(7.2시간)가 절감 되었다.

• 한국물환경학회지
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• 제23권4호
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• pp.518-526
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• 2007

There have been serious soil erosion and water pollution problems caused by highland agriculture practices at Doam-dam watershed. Especially agricultural activities, chemical and organic fertilizer and pesticide applications, soil reconditioning to maintain soil fertility are known as primary causes of soil erosion and water qaulity degradation in the receiving water bodies. Among these, soil reconditioning can accelerate soil erosion rates. To develop soil erosion prevention practices, it is necessary to estimate the soil erosion from the watershed. Thus, the Universal Soil Loss Equation (USLE) model has been developed and utilized to assess soil erosion. However, the USLE model cannot be used at watershed scale because it does not consider sediment delivery ratio (SDR) for watershed application. For this reason, the Sediment Assessment Tool for Effective Erosion Control (SA TEEC) was developed to assess the sediment yield at any point in the watershed. The USLE-based SA TEEC system can estimate the SDR using area-based SDR and slope-based SDR module. In this study, the SATEEC system was used to estimate soil erosion and sediment yield at the Doam-dam watershed using the soil properties from reconditioned agricultural fields. Based on the soil sampling and analysis, the US LE K factor was calculated and used in the SA TEEC system to analyze the possible errors of previous USLE application studies using soil properties from the digital soil map, and compared with that using soil properties obtained in this study. The estimated soil erosion at the Doam-dam watershed without using soil properties obtained in the soil sampling and analysis is 1,791,400 ton/year (123 ton/ha/year), while the soil erosion amount is 2,429,900 ton/year (166.8 ton/ha/year) with the use of soil properties from the soil sampling and analysis. There is 35 % increase in estimated soil erosion and sediment yield with the use of soil properties from soil reconditioned agricultural fields. Since significant amount of soil erosion are known to be occurring from the agricultural fields, the soil erosion and sediment yield from only agricultural fields was assessed. The soil erosion rate is 45.9 ton/ha/year without considering soil properties from soil reconditioned agricultural fields, while 105.3 ton/ha/year after considering soil properties obtained in this study, increased in 129%. This study shows that it is very important to use correct soil properties to assess soil erosion and sediment yield simulation. It is recommended that further studies are needed to develop environment friendly soil reconditioning method should be developed and implemented to decrease the speed of soil erosion rates and water quality degradation.