• Title/Summary/Keyword: Fisheries census

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Estimation and Mapping of Methane Emission from Rice Paddies in Gyunggi-do Using the Modified Water Management Scaling Factor (수정된 물관리보정인자를 적용한 경기도 논에서의 메탄 배출량 산정과 지도화)

  • Choi, Sung-Won;Kim, Hakyoung;Kim, Yeonuk;Kang, Minseok;Kim, Joon
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.18 no.4
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    • pp.320-326
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    • 2016
  • From the perspective of climate-smart agriculture, it is becoming more critical to accurately estimate the amount of greenhouse gas emissions in the agricultural sector. In order to accurately ascertain the methane emissions from rice paddies, which account for a significant portion of the emission from the agricultural sector, we used the data from the 2010 Agriculture, Forestry and Fisheries Census, the revised water management scaling factors and their calculation program. In order to facilitate the analyses and understanding, the results were mapped using the ArcGIS software. The fact that the validation of the mapped values against the actual field measurements at one site showed little difference encourages the necessity to further this study. The administrative districts-based map of methane emission can help clearly identify the regional differences. Furthermore, the analysis of their major controlling factors will provide important scientific basis for the practical policy makings for methane mitigation.

An Analysis on the Determinants of Employed Labour Quantity in the Fishing Industry (어가의 고용량 결정요인 분석)

  • Kim, Tae-Hyun;Park, Cheol-Hyung;Nam, Jongoh
    • Environmental and Resource Economics Review
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    • v.27 no.3
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    • pp.545-567
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    • 2018
  • This study applied and compared Poisson model, negative binomial model, zero inflated Poisson model, and zero inflated negative binomial model to estimate determinants of employed labour quantity. To estimate each of models, this study used fisheries census data which were obtained at microdata integrated service running by Statistics Korea. The study selected zero inflated negative binomial model according to the Vuong test and Likelihood-ratio test. In addition, the study estimated fishing village's practical changes on employed labour quantity as analyzing changes from 2010 to 2015. The results showed that the household with fishing vessels and high selling price had a significant effect on decrease of the labour quantities. Meanwhile, the longer work experience of the household, the more significant the increase in the labour quantities. In conclusion, this study presented that capitalized fishing household and the acceleration of aging had a significant impact on the change in the labour quantities.

The Spatial Distribution Characteristics and Determinants of Strong Small Farm: Focusing on Apples (강소농의 공간적 분포특성과 결정요인 분석 -사과를 중심으로-)

  • Kim, Hyun Joong;Lee, Seong Woo
    • Journal of Agricultural Extension & Community Development
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    • v.19 no.4
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    • pp.961-987
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    • 2012
  • The present study is to investigate the characteristics and determinants of spatial distribution of strong small farm by defining the term, strong small farm (SSF) extracting the SSF households data dealing with apples, from 2010 Census of Agriculture, Forestry and Fisheries, Korea. Spatial distribution and concentration of SSF are analyzed based on spatial clustering techniques. We construct discrete dependent variables on strong and non-strong small farms and then analyze the determinants of the SSFs using probit model, with independent variables including population and economic characteristics and management characteristics. As of 2010, the apple SSFs, 1,529 households in total, are geographically concentrated in Gyeonsangbuk-do according to the analysis results. The determinants of SSF are similar to those of farms' earnings. When located in the apple producing area, and participating in producers organization while selling products directly, the farm is highly likely an SSF. The findings and results of the present study are expected to provide fundamental information helpful for preparing and implementing policies for SSFs in that the present study investigates the characteristics of SSF, which is a prerequisite step for SSF-related policies.

Considerations and Alternative Approaches to the Estimation of Local Abundance of Legally Protected Species, the Fiddler Crab, Austruca lactea (법정보호종, 흰발농게(Austruca lactea) 서식 개체수 추정에 대한 검토와 대안)

  • Yoo, Jae-Won;Kim, Chang-Soo;Park, Mi-Ra;Jeong, Su-Young;Lee, Chae-Lin;Kim, Sungtae;Ahn, Dong-Sik;Lee, Chang-Gun;Han, Donguk;Back, Yonghae;Park, Young Cheol
    • Journal of Wetlands Research
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    • v.23 no.2
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    • pp.122-132
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    • 2021
  • We reviewed the methods employed in Korean tidal flat surveys to measure the local abundance of the endangered wildlife and marine protected species, the fiddler crab, Austruca lactea. A complete census for infinite population is impossible even in a limited habitat within a tidal flat, and density estimates from samples strongly vary due to diverse biological and ecological factors. The habitat boundaries and areas shift with periodicities or rhythmic activities of organisms as well as measurement errors. Hence the local abundance calculated from density and habitat areas should be regarded as transient. This conjecture was valid based on the spatio-temporal variations of the density averages, standard error ranges, and spatial distribution of the crab, A. lactea observed for 3 years (2015-2017) in Songdo tidal flat in Incheon. We proposed the potential habitat areas using the occurrence probability of 50% from logistic regression model, reflecting the importance of habitat conservation value as an alternative to local abundance. The spatial shape of potential habitat predicted from a generalized model would remain constant over time unless the species' critical environmental conditions change rapidly. The species-specific model is expected to be used for the introduction of desired species in future habitat restoration/creation projects.

Estimation and Mapping of Methane Emissions from Rice Paddies in Korea: Analysis of Regional Differences and Characteristics (전국 논에서 발생하는 메탄 배출량의 산정 및 지도화: 지역 격차 및 특성 분석)

  • Choi, Sung-Won;Kim, Joon;Kang, Minseok;Lee, Seung Hoon;Kang, Namgoo;Shim, Kyo-Moon
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.20 no.1
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    • pp.88-100
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    • 2018
  • Methane emissions from rice paddies are the largest source of greenhouse gases in the agricultural sector, but there are significant regional differences depending on the surrounding conditions and cultivation practices. To visualize these differences and to analyze their causes and characteristics, the methane emissions from each administrative district in South Korea were calculated according to the IPCC guidelines using the data from the 2010 Agriculture, Forestry and Fisheries Census, and then the results were mapped by using the ArcGIS. The nationwide average of methane emissions per unit area was $380{\pm}74kg\;CH_4\;ha^{-1}\;yr^{-1}$. The western region showed a trend toward higher values than the eastern region. One of the major causes resulting in such regional differences was the $SF_o$ (scaling factor associated with the application of organic matter), where the number of cultivation days played an important role to either offset or deepen the differences. Comparison of our results against the actual methane emissions data observed by eddy covariance flux measurement in the three KoFlux rice paddy sites in Gimje, Haenam and Cheorwon showed some differences but encouraging results with a difference of 10 % or less depending on the sites and years. Using the updated GWP (global warming potential) value of 28, the national total methane emission in 2010 was estimated to be $8,742,000tons\;CO_2eq$ - 13% lower than that of the National Greenhouse Gas Inventory Report (i.e., $10,048,000tons\;CO_2eq$). The administrative districts-based map of methane emissions developed in this study can help identify the regional differences, and the analysis of their key controlling factors will provide important scientific basis for the practical policy makings for methane mitigation.