Quantification of Changes in Rice Production for 2003–2019 with MODIS LAI Data in Pursat Province, Cambodia
Rice is not merely a staple food but an important source of income in Cambodia. Rapid socioeconomic development in the country affects farmers’ management practices, and rice production has increased almost three-fold over two decades. However, detailed information about the recent changes in rice p...
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MDPI AG
2021-05-01
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| Series: | Remote Sensing |
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| Online Access: | https://www.mdpi.com/2072-4292/13/10/1971 |
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| author | Yu Iwahashi Rongling Ye Satoru Kobayashi Kenjiro Yagura Sanara Hor Kim Soben Koki Homma |
| author_facet | Yu Iwahashi Rongling Ye Satoru Kobayashi Kenjiro Yagura Sanara Hor Kim Soben Koki Homma |
| author_sort | Yu Iwahashi |
| collection | DOAJ |
| description | Rice is not merely a staple food but an important source of income in Cambodia. Rapid socioeconomic development in the country affects farmers’ management practices, and rice production has increased almost three-fold over two decades. However, detailed information about the recent changes in rice production is quite limited and mainly obtained from interviews and statistical data. Here, we analyzed MODIS LAI data (MCD152H) from 2003 to 2019 to quantify rice production changes in Pursat Province, one of the great rice-producing areas in Cambodia. Although the LAI showed large variations, the data clearly indicate that a major shift occurred in approximately 2010 after applying smoothing methods (i.e., hierarchical clustering and the moving average). This finding is consistent with the results of the interviews with the farmers, which indicate that earlier-maturing cultivars had been adopted. Geographical variations in the LAI pattern were illustrated at points analyzed along a transverse line from the mountainside to the lakeside. Furthermore, areas of dry season cropping were detected by the difference in monthly averaged MODIS LAI data between January and April, which was defined as the dry season rice index (DSRI) in this study. Consequently, three different types of dry season cropping areas were recognized by nonhierarchical clustering of the annual LAI transition. One of the cropping types involved an irrigation-water-receiving area supported by canal construction. The analysis of the peak LAI in the wet and dry seasons suggested that the increase in rice production was different among cropping types and that the stagnation of the improvements and the limitation of water resources are anticipated. This study provides valuable information about differences and changes in rice cropping to construct sustainable and further-improved rice production strategies. |
| first_indexed | 2024-03-10T11:17:44Z |
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| institution | Directory Open Access Journal |
| issn | 2072-4292 |
| language | English |
| last_indexed | 2024-03-10T11:17:44Z |
| publishDate | 2021-05-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Remote Sensing |
| spelling | doaj.art-0d83c6e351614b9a87cac81b313f55a42023-11-21T20:15:51ZengMDPI AGRemote Sensing2072-42922021-05-011310197110.3390/rs13101971Quantification of Changes in Rice Production for 2003–2019 with MODIS LAI Data in Pursat Province, CambodiaYu Iwahashi0Rongling Ye1Satoru Kobayashi2Kenjiro Yagura3Sanara Hor4Kim Soben5Koki Homma6Graduate School of Agricultural Science, Tohoku University, Sendai 9808572, JapanGraduate School of Agricultural Science, Tohoku University, Sendai 9808572, JapanCenter for Southeast Asian Studies, Kyoto University, Kyoto 6068501, JapanFaculty of Economics, Hannan University, Matsubara 5808502, JapanFaculty of Land Management and Land Administration, Royal University of Agriculture, Phnom Penh 12401, CambodiaCenter for Agricultural and Environmental Studies, Royal University of Agriculture, Phnom Penh 12401, CambodiaGraduate School of Agricultural Science, Tohoku University, Sendai 9808572, JapanRice is not merely a staple food but an important source of income in Cambodia. Rapid socioeconomic development in the country affects farmers’ management practices, and rice production has increased almost three-fold over two decades. However, detailed information about the recent changes in rice production is quite limited and mainly obtained from interviews and statistical data. Here, we analyzed MODIS LAI data (MCD152H) from 2003 to 2019 to quantify rice production changes in Pursat Province, one of the great rice-producing areas in Cambodia. Although the LAI showed large variations, the data clearly indicate that a major shift occurred in approximately 2010 after applying smoothing methods (i.e., hierarchical clustering and the moving average). This finding is consistent with the results of the interviews with the farmers, which indicate that earlier-maturing cultivars had been adopted. Geographical variations in the LAI pattern were illustrated at points analyzed along a transverse line from the mountainside to the lakeside. Furthermore, areas of dry season cropping were detected by the difference in monthly averaged MODIS LAI data between January and April, which was defined as the dry season rice index (DSRI) in this study. Consequently, three different types of dry season cropping areas were recognized by nonhierarchical clustering of the annual LAI transition. One of the cropping types involved an irrigation-water-receiving area supported by canal construction. The analysis of the peak LAI in the wet and dry seasons suggested that the increase in rice production was different among cropping types and that the stagnation of the improvements and the limitation of water resources are anticipated. This study provides valuable information about differences and changes in rice cropping to construct sustainable and further-improved rice production strategies.https://www.mdpi.com/2072-4292/13/10/1971Cambodiadry season croppingleaf area indexMODISremote sensingrice |
| spellingShingle | Yu Iwahashi Rongling Ye Satoru Kobayashi Kenjiro Yagura Sanara Hor Kim Soben Koki Homma Quantification of Changes in Rice Production for 2003–2019 with MODIS LAI Data in Pursat Province, Cambodia Remote Sensing Cambodia dry season cropping leaf area index MODIS remote sensing rice |
| title | Quantification of Changes in Rice Production for 2003–2019 with MODIS LAI Data in Pursat Province, Cambodia |
| title_full | Quantification of Changes in Rice Production for 2003–2019 with MODIS LAI Data in Pursat Province, Cambodia |
| title_fullStr | Quantification of Changes in Rice Production for 2003–2019 with MODIS LAI Data in Pursat Province, Cambodia |
| title_full_unstemmed | Quantification of Changes in Rice Production for 2003–2019 with MODIS LAI Data in Pursat Province, Cambodia |
| title_short | Quantification of Changes in Rice Production for 2003–2019 with MODIS LAI Data in Pursat Province, Cambodia |
| title_sort | quantification of changes in rice production for 2003 2019 with modis lai data in pursat province cambodia |
| topic | Cambodia dry season cropping leaf area index MODIS remote sensing rice |
| url | https://www.mdpi.com/2072-4292/13/10/1971 |
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