• 제목/요약/키워드: agricultural ecosystem

검색결과 615건 처리시간 0.022초

여름철 일 최고기온과 일사량의 최근 변동에 관하여 (On Recent Variations in Solar Radiation and Daily Maximum Temperature in Summer)

  • 최미희;윤진일
    • 한국농림기상학회지
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    • 제11권4호
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    • pp.185-191
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    • 2009
  • 여름을 제외한 다른 계절의 온난화 혹은 일 최저기온에 대한 온실효과와 도시열섬효과에 관한 연구가 활발히 수행되었던 것에 비하면 여름철의 기온상승, 특히 일 최고기온의 상승에 대한 연구는 미흡하다. 최근 25년간 전국 18개 지점에서 관측된 우리나라의 여름철(6-8월) 일 최고기온 변화를 조사하고 그 변화에 미친 일사량의 영향을 분석한 결과, 평년(1971-2000)에 비해 하루 평균 일사량은 $0.61MJ\;m^{-2}$ 증가하였으며 같은 기간 일 최고기온은 $0.1^{\circ}C$ 상승한 것으로 확인된다. 이 기간 중 일사량의 연차변이는 여름 최고기온 연차변이의 65%를 설명할 수 있었다. 일사량의 증가는 대기투과율의 증가에 기인하며 대기투과율의 증가는 에어로졸 농도 특히 아황산가스 농도 감소 때문인 것으로 판단된다. 1999년부터 2007년까지 여름철 아황산가스 농도가 계속 감소해왔는데 이와 같은 경향이 앞으로도 지속된다면 대기투과율 증가 및 이에 따른 일사량 증가와 증가된 일사량으로 인한 최고기온 상승을 예상할 수 있다.

농촌전통테마마을 활성화를 위한 내곡리 여산팔경 마을 생태탐방로 노선설정 방안 연구 (Developing Ecological Trails and Route Alignment for Revitalizing Rural Traditional Theme Village in Naegok-ri)

  • 이승주;한봉호;강현경;이수동;김상범
    • 농촌계획
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    • 제15권3호
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    • pp.61-79
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    • 2009
  • This study discusses developing ecological trails and route alignment in mountainous rural area. Through a process of ecological resources survey, ecological trails and route alignment has been established. Mainly, by focusing on ecological resources in rural areas, it was indifferent to their own ecological resource and charm to make it unique strengths. Based on survey the results, Natural ecology resources, there were the climate factor, surface, geological, terrain analysis. Furthermore, ecological resources were researched and analyzed the elements of it, distribution of resources, types, location, semantic analysis. The results are expressed on the map and recorded by taking pictures. Plant ecosystem, there were actual vegetation, land use, flora analysis. Wild animal ecosystem, it was checked and recorded on 1/1,000 map partition the emergence of wild birds, the number of species distributed by foraging guild, the emergence of amphibians, reptile, mammals and insect species. The site is chosen as rural theme village in 2007, base on their own rich ecological and landscape resources. Therefore, we carried out ecological trails and route alignment plan in accordance with analyzed the natural ecological resource and after setting up the basic goal, ecological trail has been composed and planting has done and direction.

Evaluation of Water Quality Characteristics and Ecosystem Health of Yongpung Reservoir, Korea

  • Lim, Dohun;Lee, Yoonjin;Kim, Kyung
    • 한국환경보건학회지
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    • 제45권1호
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    • pp.42-53
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    • 2019
  • Objectives: The Yongpung reservoir in Korea is a crucial facility that supplies water to farms in its surrounding $2km^2$ area. However, its water quality is not suited to the needs of current residents who wish for the availability of environmentally friendly agricultural products and desire to use the waterfront area. The aim of this research was to evaluate the reservoir's fish and benthic macroinvertebrate distributions and determine its water quality and the heavy metal content in its sediment. This basic data can be used to establish environmentally protective plans for the Yongpung reservoir. Methods: Six sites were selected for analysis in this investigation. Three points (YP-1, YP-2, and YP-3) were evaluated for water quality and metal content in sediments; they were located upstream, midstream, and downstream of the reservoir. Samplings of the fish and benthic macroinvertebrate populations were performed at three other sites: St. 1, St. 2, and St. 3. Results: Based on chemical oxygen demand (COD) and total nitrogen (T-N) data, the quality of the Yongpung reservoir water corresponds to Class VI (very poor) according to Korea's lake environmental standards. The lead levels measured in the sediment at the midstream and downstream points of the reservoir were 76.7 and 72.7 mg/kg, respectively, while 8 orders, 15 families, and 16 species of benthic macroinvertebrates were identified in the reservoir. The ecological score of the benthic macroinvertebrate community (ESB) was between 8 and 23, denoting poor to very poor environmental conditions. Further, 4 families and 7 species of fish were identified in the reservoir, with Cyprinidae accounting for 94.3% of all observed freshwater fish. Conclusion: Based on these findings, we conclude that management plans, including the removal of lead from the sediment, are necessary to improve the quality of the agricultural water in this reservoir. The T. japonica, which cover almost 30% of the water area, must also be removed.

상습침수 농경지의 토지평가를 위한 고도별 침수 잠재성 분석 - 경상남도 창녕군 이방면을 대상으로 - (Analysis of the Inundation Potential by Elevation for the Land Evaluation in the Potentially Inundated Farms - A Case Study in Ibang-myeon, Changnyeong-gun, Kyungsangnamdo -)

  • 박인환;장갑수;서동조
    • 한국조경학회지
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    • 제33권2호
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    • pp.71-82
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    • 2005
  • A large scale of riverside rearrangement has been recently done in the major rivers in Korea. So inundation possibility in agricultural area closed by these rivers has been higher than the possibility a few years ago. However, land use in this area has not been adjusted to a change of this situation near the rivers. Therefore, when typhoon or heavy rain is happened on this area, it can cause a large damage in agricultural area. This study analyzed inundation potentiality in agricultural area at Ibang-myeon, Changnyeong-gun, Kyeongnam-province, Korea by using the logistic regression model and the piecewise regression model. The first thing we did was to transfer the inundation area per elevation to the accumulated inundation area per elevation. This accumulated inundation area per elevation as an distribution function could be described by the logistic regression model(LRM), and piecewise regression model(PRM) could make it much more accurate to analyze the inundation area per elevation. As a result, the regression models derived from LRM and PRM showed $R^2$ over 0.950. The models derived from LRM and PRM in Ibang-myeon noted that frequently inundated area(FIA) was shown up to 12.12m in elevation, and potentially inundated area(PIA) was shown up to 14.60m in elevation. In FIA, regular agricultural activity would be impossible. And It would be not easy to continue the regular agricultural activity in PIA. So, this land should be rearranged to be used for a buffer zone for ecosystem protection, landscape conservation and things like that in riverside.

Assessment of Soil Microbial Communities in Carotenoid-Biofortified Rice Ecosystem

  • Sohn, Soo-In;Oh, Young-Ju;Kim, Byung-Yong;Lee, Bumkyu;Lee, Si-Myung;Oh, Sung-Dug;Lee, Gang-Seob;Yun, Doh-Won;Cho, Hyun-Suk
    • 한국토양비료학회지
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    • 제48권5호
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    • pp.442-450
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    • 2015
  • This study was conducted to investigate the effect of Psy-2A-CrtI (PAC), a genetically modified (GM) rice with enhanced ${\beta}$-carotene, on the soil microbial community. The soil used to cultivate GM rice and its wild-type, Nakdong, was analyzed for population density, denaturing gradient gel electrophoresis (DGGE), and pyrosequencing. It was found that the bacterial, fungal and actinomycetes population densities of the PAC soils were within the range of those of the non-GM rice cultivar, Nakdong. The DGGE banding patterns of the GM and non-GM soils were also similar, suggesting that the bacterial community structures were stable within a given month and were unaffected by the presence of a GM plant. The pyrosequencing result showed a temporal difference in microorganism taxon and distribution ratio, but no significant difference between GM and non-GM was found. The persistence of the transgene DNA in the plant and surrounding soil were investigated for different time periods. There were differences in the persistence within the plant depending on the gene, but they could not be detected after 5 weeks. Also the transgenes were not detected in the surrounding soil. These results indicate that soil microbial communities are unaffected by the cultivation of a PAC rice within the experimental time frame.

월동기 논 생태계 절지동물의 생물다양성 (Biodiversity of Overwintering Arthropods in a Paddy Field Ecosystem)

  • 서화영;이경주;황인수;주정일;김광호;공민재;최용석
    • 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).

범용토양유실공식(RUSLE) 기법을 활용한 금호강 수변지역의 토양유실위험도 비교 분석 (Utilizing the Revised Universal Soil Loss Equation (RUSLE) Technique Comparative Analysis of Soil Erosion Risk in the Geumhogang Riparian Area)

  • 김정철;윤정도;박정수;최종윤;윤종학
    • 대한원격탐사학회지
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    • 제34권2_1호
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    • pp.179-190
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    • 2018
  • 본 연구는 하천 유역의 정비사업 전 후의 토양유실위험도를 비교하기 위하여 GIS 및 디지타이징 자료를 토대로 수정범용토양유실공식(RUSLE)을 활용하여 분석하였다. 토양유실량을 파악하기 위하여 토지피복지도, 지형도, 토양도, 강수량 등의 자료들을 이용하였으며, 금호강 유역의 수변지역을 범위로 디지타이징한 후, 유역을 행정구역 단위로 분할하여 분석하였다. 하천 정비 전('8)과 후('16)로 토양유실이 전혀 일어나지 않는 지역(클래스 1)에서 심하게 일어나는 지역(클래스 5) 등 총 5단계로 구분하여 분석한 결과, 사업('16) 후 전체지역에 대하여 1, 5 클래스는 감소, 2~4 클래스는 증가한 것으로 나타났다. 대구와 영천은 5 클래스의 면적이 감소하였고, 경산은 5 클래스의 지역이 존재하지 않았다. 이러한 원인은 공원조성과 인공시설물 확대, 농경지 감소 등으로 인하여 5 클래스의 지역이 감소한 것으로 판단되며, 수변지역의 준설 및 공원조성을 위한 하안선 단순화는 하천 유량 및 유속에 의한 토양유실량 증가가 일어난 것으로 추정된다.

Conservation potential of North American large rivers: the Wabash River compared with the Ohio and Illinois rivers

  • Pyron, Mark;Muenich, Rebecca Logsdon;Casper, Andrew F.
    • Fisheries and Aquatic Sciences
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    • 제23권6호
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    • pp.15.1-15.14
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    • 2020
  • Background: Large rivers are ecological treasures with high human value, but most have experienced decades of degradation from industrial and municipal sewage, row-crop agricultural practices, and hydrologic alteration. We reviewed published analyses of long-term fish diversity publications from three intensively managed large river ecosystems to demonstrate the conservation potential of large river ecosystems. Results: We show how the incorporation of recent advances in river concepts will allow a better understanding of river ecosystem functioning and conservation. Lastly, we focus on the Wabash River ecosystem based on high conservation value and provide a list of actions to maintain and support the ecosystem. In the Wabash River, there were originally 66 species of freshwater mussels, but now only 30 species with reproducing populations remain. Although there were multiple stressors over the last century, the largest change in Wabash River fish biodiversity was associated with rapid increases in municipal nutrient loading and invasive bigheaded carps. Conclusions: Like similarly neglected large river systems worldwide, the Wabash River has a surprising amount of ecological resilience and recovery. For instance, of the 151 native fish species found in the 1800s, only three species have experienced local extinctions, making the modern assemblage more intact than many comparable rivers in the Mississippi River basin. However, not all the changes are positive or support the idea of recovery. Primary production underpins the productivity of these ecosystems, and the Wabash River phytoplankton assemblages shifted from high-quality green algae in the 1970s to lower less nutritional blue-green algae as nutrient and invasive species have recently increased. Our recommendations for the Wabash River and other altered rivers include the restoration of natural hydrology for the mainstem and tributaries, nutrient reductions, mechanisms to restore historical hydrologic patterns, additional sediment controls, and improved local hydraulics.

Wetland Construction: Flood Control and Water Balance Analysis

  • Kim, Duck-Gil;Kwak, Jae-Won;Kim, Soo-Jun;Kim, Hung-Soo;Ahn, Tae-Jin;Singh, Vijay P.
    • Environmental Engineering Research
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    • 제15권4호
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    • pp.197-205
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    • 2010
  • Recent years have witnessed increasing interest in wetland constructions in Korea as a flood control measure during the flood season and for consideration of the ecology during the non-flood season. In this study, hydraulic and hydrologic analyses were performed on a wetland construction plan for use as an alternative sustainable flood defense during the flood season, as well as a wetland that can protect the ecosystem during the non-flood season. The study area was the basin of the Topyeong-cheon stream, which is a tributary of the Nakdong River, including the Upo wetland, which is registered in the Ramsar Convention and the largest inland wetland in Korea. Wetlands were to be constructed at upstream and downstream of the Upo wetland by considering and analyzing seven scenarios for their constructions to investigate the effect of flood control during the flood season; it was found the best scenario reduced the flood level by 0.56 m. To evaluate the usefulness of the constructed wetlands during the non flood season, the water balance in the wetlands was analyzed, with the best scenario found to maintain a minimum water level of 1.3 m throughout the year. Therefore, the constructed wetlands could provide an alternative measure for flood prevention as well as an ecosystem for biodiversity.

자기조직화지도(Self-organizing map)와 랜덤 포레스트 분석(Random forest)을 이용한 논습지에 도래하는 수조류 군집 특성 파악 (Patterning Waterbird Assemblages on Rice Fields Using Self-Organizing Map and Random Forest)

  • 남형규;최승혜;유정칠
    • 한국환경농학회지
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    • 제34권3호
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    • pp.168-177
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    • 2015
  • BACKGROUND: In recent year, there has been great concern regarding agricultural land uses and their importance for the conservation of biodiversity. Rice fields are managed unique wetland for wildlife, especially waterbirds. A comprehensive monitoring of the waterbird assemblage to understand patterning changes was attempted for rice ecosystem in South Korea. This rice ecosystem has been recognized as one of the most important for waterbirds conservation. METHODS AND RESULTS: Biweekly monitoring was implemented for the 4 years from April 2009 to March 2010, from April 2011 to March 2014. 32 species of waterbirds were observed. Self-organizing map (SOM) and random forest were applied to the waterbirds dataset to identify the characteristics in waterbirds distribution. SOM and random forest analysis clearly classified into four clusters and extract ecological information from waterbird dataset. Waterbird assemblages represented strong seasonality and habitat use according to waterbird group such as shorebirds, herons and waterfowl. CONCLUSION: Our results showed that the combination of SOM and random forest analysis could be useful for ecosystem assessment and management. Furthermore, we strongly suggested that a strict management strategy for the rice fields to conserve the waterbirds. The strategy could be seasonally and species specific.