• Title/Summary/Keyword: Anthropogenic impacts

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Soil Classification of Anthropogenic Soils in a Remodeled Area Using Soil Taxonomy and World Reference Base for Soil Resources

  • Lee, Seung-Been;Chun, Hyen-Chung;Cho, Hyun-Jun;Hyun, Byung-Keun;Song, Kwan-Cheol;Zhang, Yong-Seon;Sonn, Yeon-Kyu;Park, Chan-Won
    • Korean Journal of Soil Science and Fertilizer
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    • v.46 no.6
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    • pp.536-541
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    • 2013
  • In Soil Taxonomy system, anthropogenic soils are still classified as Entisols since the International Classification Committee for Anthropogenic Soils is in the process of classifying anthropogenic soils as new orders. In reality, it is difficult to characterize anthropogenic soils because Soil Taxonomy (ST) system does not distinguish between natural and anthropogenic Entisols. On the other hand, World Reference Base for soil resources (WRB) considers human impacts on soils and contains an independent category of anthropogenic soils, which makes easier to understand anthropogenic soil characteristics than Soil Taxonomy system. A remodeled paddy field (Gasan) was selected to classify by ST and WRB. Soil samples were taken to analyze chemical and physical properties. Based on the results of the analyses, the ST system classified Gasan as coarse loamy, mixed, mesic, Aquic Udorthents while the WRB did as Stagnic Urbic Technosols (Oxyaquic, Arenic). As a conclusion, the WRB classification information of the anthropogenic provides more detail characteristics of the anthropogenic soils.

External mechanisms driving ecosystem changes in a coastal wetland, the Mississippi Delta, USA

  • Ryu, Junghyung;Liu, Kam-biu;McCloskey, Terrence A.;Yun, Sang-Leen
    • Proceedings of the Korea Water Resources Association Conference
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    • 2022.05a
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    • pp.85-85
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    • 2022
  • The world's most extensive and active deltas, Louisiana's wetlands, are deteriorating rapidly due to multiple stressors such as the discharge of the Mississippi River, sea-level rise, and coastal retreat, the substantial but spatially and temporally variable impacts. However, the ecological and anthropogenic histories, the mode of environmental changes on a multi-millennial timescale have not been thoroughly documented. This study, a palynology-based multiproxy analysis, investigates hydrological, geological, geochemical, and anthropogenic impacts on southern Louisiana wetlands and a variety of external forcing agents influencing ecological succession. Sediment cores extracted from a small pond on a mangrove-dominate island near Port Fourchon, Louisiana, USA yielded a 4,000-year record. The site has been transformed from freshwater to saline water environments, to a mangrove dominant island over the late Holocene. The multivariate principal component analysis identified the relative strength of external drivers responsible for each ecological shift. The Mississippi River delta cycle (lobe switching) was the dominant driver of ecosystem changes during the late Holocene, while relative sea-level rise, tropical cyclones, climate, and anthropogenic effects have been the main drivers late in the site's history.

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Exploring the factors responsible for variation in streamflow using different Budyko-base functions

  • Shah, Sabab Ali;Jehanzaib, Muhammad;Kim, Min Ji;Kim, Tae-Woong
    • Proceedings of the Korea Water Resources Association Conference
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    • 2022.05a
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    • pp.140-140
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    • 2022
  • Recently an accurate quantification of streamflow under various climatological and anthropogenic factors and separation of their relative contribution remains challenging, because variation in streamflow may result in hydrological disasters. In this study, we evaluated the factors responsible for variation in streamflow in Korean watersheds, quantified separately their contribution using different Budyko-based functions, and identified hydrological breakpoint points. After detecting that the hydrological break point in 1995 and time series were divided into natural period (1966-1995), and disturbed period (1996-2014). During the natural period variation in climate tended to increase change in streamflow. However, in the disturbed period both climate variation and anthropogenic activities tended to increase streamflow variation in the watershed. Subsequently, the findings acquired from different Budyko-based functions were observed sensitive to selection of function. The variation in streamflow was observed in the response of change in climatic parameters ranging 46 to 75% (average 60%). The effects of anthropogenic activities were observed less compared to climate variation accounts 25 to 54% (average 40%). Furthermore, the relative contribution was observed to be sensitive corresponding to Budyko-based functions utilized. Moreover, relative impacts of both factors have capability to enhance uncertainty in the management of water resources. Thus, this knowledge would be essential for the implementation of water management spatial and temporal scale to reduce the risk of hydrological disasters in the watershed.

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A Comparison of the Impact of Regional Anthropogenic Climatic Change in Urban and Rural Areas in South Korea (1955-2016) (최근 60년간 도시 및 농촌 지역의 국지적 기후변화 비교 분석)

  • Yoon, Dong-Hyun;Nam, Won-Ho;Hong, Eun-Mi;Kim, Taegon;Ho, Chang-Hoi;Hayes, Michael J.
    • Journal of The Korean Society of Agricultural Engineers
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    • v.60 no.3
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    • pp.37-50
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    • 2018
  • Local climate characteristics for both urban and rural areas can be attributed to multiple factors. Two factors affecting these characteristics include: 1) greenhouse gases related to global warming, and 2) urban heat island (UHI) effects caused by changes in surface land use and energy balances related to rapid urbanization. Because of the unique hydrological and climatological characteristics of cities compared with rural and forested areas, distinguishing the impacts of global warming urbanization is important. In this study, we analyzed anthropogenic climatic changes caused by rapid urbanization. Weather elements (maximum temperature, minimum temperature, and precipitation) over the last 60 years (1955-2016) are compared in urban areas (Seoul, Incheon, Pohang, Daegu, Jeonju, Ulsan, Gwangju, Busan) and rural/forested areas (Gangneung, Chupungnyeong, Mokpo, and Yeosu). Temperature differences between these areas reveal the effects of urbanization and global warming. The findings of this study can be used to analyze and forecast the impacts of climate change and urbanization in other urban and non-urban areas.

Impacts of anthropogenic heating on urban boundary layer in the Gyeong-In region (인공열이 도시경계층에 미치는 영향 - 경인지역을 중심으로 -)

  • Koo, Hae-Jung;Ryu, Young-Hee
    • Journal of Environmental Impact Assessment
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    • v.21 no.5
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    • pp.665-681
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    • 2012
  • This study investigates the influence of anthropogenic heat (AH) release on urban boundary layer in the Gyeong-In region using the Weather Research and Forecasting model that includes the Seoul National University Urban Canopy Model (SNUUCM). The gridded AH emission data, which is estimated in the Gyeong-In region in 2002 based on the energy consumption statistics data, are implemented into the SNUUCM. The simulated air temperature and wind speed show good agreement with the observed ones particularly in terms of phase for 11 urban sites, but they are overestimated in the nighttime. It is found that the influence of AH release on air temperature is larger in the nighttime than in the daytime even though the AH intensity is larger in the daytime. As compared with the results with AH release and without AH release, the contribution of AH release on urban heat island intensity is large in the nighttime and in the morning. As the AH intensity increases, the water vapor mixing ratio decreases in the daytime but increases in the nighttime. The atmospheric boundary layer height increases greatly in the morning (0800 - 1100 LST) and midnight (0000 LST). These results indicate that AH release can have an impact on weather and air quality in urban areas.

Ecological impact of fast industrialization inferred from a sediment core in Seocheon, West Coast of Korean Peninsula

  • Choi, Rack Yeon;Kim, Heung-Tae;Yang, Ji-Woong;Kim, Jae Geun
    • Journal of Ecology and Environment
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    • v.44 no.4
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    • pp.212-221
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    • 2020
  • Background: Rapid industrialization has caused various impacts on nature, including heavy metal pollution. However, the impacts of industrialization vary depending on the types of industrializing activity and surrounding environment. South Korea is a proper region because the rapid socio-economical changes have been occurred since the late nineteenth century. Therefore, in this study, we estimate the anthropogenic impacts on an ecosystem from a sediment core of Yonghwasil-mot, an irrigation reservoir on the western coast of Korea, in terms of heavy metal concentrations, nutrient influx, and pollen composition. Results: The sediment accumulation rate (SAR) determined by 210Pb geochronology showed two abrupt peaks in the 1930s and 1950s, presumably because of smelting activity and the Korean War, respectively. The following gradual increase in SAR may reflect the urbanization of recent decades. The average concentrations of arsenic (As), copper (Cu), and lead (Pb) during the twentieth century were > 48% compared to those before the nineteenth century, supporting the influence of smelting activity. However, at the beginning of the twenty-first century, the As, Cu, and Pb concentrations decreased by 19% compared to levels in the twentieth century, which is coincident with the closure of the smelter in 1989 and government policy banning leaded gasoline since 1993. The pollen assemblage and nutrient input records exhibit changes in vegetation cover and water level of the reservoir corresponding to anthropogenic deforestation and reforestation, as well as to land-use alteration. Conclusions: Our results show that the rapid socio-economic development since the twentieth century clearly affected the vegetation cover, land use, and metal pollutions.

Simulation of Air Quality Over South Korea Using the WRF-Chem Model: Impacts of Chemical Initial and Lateral Boundary Conditions (WRF-Chem 모형을 이용한 한반도 대기질 모의: 화학 초기 및 측면 경계 조건의 영향)

  • Lee, Jae-Hyeong;Chang, Lim-Seok;Lee, Sang-Hyun
    • Atmosphere
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    • v.25 no.4
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    • pp.639-657
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    • 2015
  • There is an increasing need to improve the air quality over South Korea to protect public health from local and remote anthropogenic pollutant emissions that are in an increasing trend. Here, we evaluate the performance of the WRF-Chem (Weather Research and Forecasting-Chemistry) model in simulating near-surface air quality of major Korean cities, and investigate the impacts of time-varying chemical initial and lateral boundary conditions (IC/BCs) on the air quality simulation using a chemical downscaling technique. The model domain was configured over the East Asian region and anthropogenic MICS-Asia 2010 emissions and biogenic MEGAN-2 emissions were applied with RACM gaseous chemistry and MADE/SORGAM aerosol mechanism. Two simulations were conducted for a 30-days period on April 2010 with chemical IC/BCs from the WRF-Chem default chemical species profiles ('WRF experiment') and the MOZART-4 (Model for OZone And Related chemical Tracers version 4) ('WRF_MOZART experiment'), respectively. The WRF_MOZART experiment has showed a better performance to predict near-surface CO, $NO_2$, $SO_2$, and $O_3$ mixing ratios at 7 major Korean cities than the WRF experiment, showing lower mean bias error (MBE) and higher index of agreement (IOA). The quantitative impacts of the chemical IC/BCs have depended on atmospheric residence time of the pollutants as well as the relative difference of chemical mixing ratios between the WRF and WRF_MOZART experiments at the lateral boundaries. Specifically, the WRF_MOZART experiment has reduced MBE in CO and O3 mixing ratios by 60~80 ppb and 5~10 ppb over South Korea than those in the WRF-Chem default simulation, while it has a marginal impact on $NO_2$ and $SO_2$ mixing ratios. Without using MOZART-4 chemical IC, the WRF simulation has required approximately 6-days chemical spin-up time for the East Asian model domain. Overall, the results indicate that realistic chemical IC/BCs are prerequisite in the WRF-Chem simulation to improve a forecast skill of local air quality over South Korea, even in case the model domain is sufficiently large to represent anthropogenic emissions from China, Japan, and South Korea.

Bio-Economic Relationships between Climate Change and Fisheries (기후변화와 수산업의 관계에 관한 연구)

  • Park, Seong-Kwae;Kwon, Hyeok-Jun;Park, Jong-Wun;Cha, Cheol-Pyo
    • Journal of Fisheries and Marine Sciences Education
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    • v.22 no.3
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    • pp.388-401
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    • 2010
  • This research aims at analyzing impacts of climate change on fisheries. Climate change is an additional pressure on top of the many which fish stocks already experience. This implies that the impact of climate change must be evaluated in the context of other anthropogenic pressures, which often have a much greater and more immediate effect. Conversely, it is evident that fish stocks will be more resilient to climate impacts if the stresses due to other factors, such as over-fishing and pollution, are minimized. Improved management of fisheries and of marine ecosystems can undoubtedly play an important role in adapting to the impacts of climate change. Most of the improvements which are needed do not require new science or understanding, they require patient development of acceptable, effective, responsive social institutions and instruments for achieving adaptive management. Management advices must include complete and transparent information on risks and uncertainties which arise from data quality and from structural deficiencies in the assessment models. Well-designed and reliable monitoring of fish stocks and the marine ecosystem is essential in order to detect changes and give warning in advance of alterations in the productivity of individual species and of the structure and functioning of the ecosystem and fishery economy on which they depend.

Global Carbon Cycle and Budget Study (지구규모의 탄소 순환 및 물질수지 연구)

  • 권오열
    • Journal of Environmental Science International
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    • v.5 no.4
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    • pp.429-440
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    • 1996
  • A global carbon cycle model (GCCM), that incorporates interaction among the terrestrial biosphere, ocean, and atmosphere, was developed to study the carbon cycling aid global carbon budget, especially due to anthropogenic $CO_2$ emission. The model that is based on C, 13C and 14C mass balance, was calibrated with the observed $CO_2$ concentration, $\delta$13C and $\Delta$14C in the atmosphere, Δ14C in the soil, and $\Delta$14C in the ocean. Also, GCCM was constrained by the literature values of oceanic carbon uptake and CO, emissions from deforestation. Inputs (forcing functions in the model) were the C, 13C and 14C as $CO_2$ emissions from fossil fuel use, and 14C injection into the stratosphere by bomb-tests. The simulated annual carbon budget of 1980s due to anthropoRenic $CO_2$ shows that the global sources were 5.43 Gt-C/yr from fossil fuel use and 0.91 Gt-C/yr from deforestation, and the sinks were 3.29 Gt-C/yr in the atmosphere, 0.90 Gt-C/yr in the terrestrial biosphere and 2.15 Gt-C/yr in the ocean. The terrestrial biosphere is currently at zero net exchange with the atmosphere, but carbon is lost cia organic carbon runoff to the ocean. The model could be utilized for a variety of studies in $CO_2$ policy and management, climate modeling, $CO_2$ impacts, and crop models.

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