VIETNAM NATIONAL UNIVERSITY, HANOI VIETNAM JAPAN UNIVERSITY TRAN THUY TRANG ASSESSING CROPPING PATTERN ADAPTABILITY TO CLIMATE RISKS IN THE VIETNAMESE MEKONG RIVER DELTA MASTER'S THESIS VIETNAM NATIONAL UNIVERSITY, HANOI VIETNAM JAPAN UNIVERSITY TRAN THUY TRANG ASSESSING CROPPING PATTERN ADAPTABILITY TO CLIMATE RISKS IN THE VIETNAMESE MEKONG RIVER DELTA MAJOR: CLIMATE CHANGE AND DEVELOPMENT CODE: 8900201.02QTD RESEARCH SUPERVISOR: Dr. AKIHIKO KOTERA Dr. NGUYEN THI THUY HANG Hanoi, 2023 PLEDGE I pledge that this thesis is original and has not been published before. I am aware of the regulations regarding using other research and documents, and I will ensure that all citations and references adhere to the requirements.
I have reviewed the guidelines on plagiarism violations. I solemnly declare that the research presented in this thesis is my own and does not infringe upon the Regulation on Prevention of Plagiarism in Academic and Scientific Research Activities at VNU Vietnam Japan University (Issued together with Decision No 700/QD-ĐHVN dated 30/9/2021 by the Rector of Vietnam Japan University). Author of the thesis Tran Thuy Trang ACKNOWLEDGEMENT I would like to express my sincere gratitude to the following individuals and groups who have played a significant role in the completion of my master's thesis: First and foremost, I would like to extend my deepest appreciation to my main supervisor, Dr. His guidance, support, and encouragement throughout the research process have been invaluable.
I am also grateful for his sponsorship of the field trip, which provided me with valuable firsthand experience and enriched my understanding of the subject matter. I am indebted to Dr. Nguyen Thi Thuy Hang for her technical expertise and professional advice. Her insightful feedback and constructive criticism have contributed significantly to the improvement of this thesis.
I would like to acknowledge my classmates, who have been an incredible source of support throughout this journey. Their camaraderie, willingness to help and mutual care for one another have created a positive and conducive learning environment. Late-night study sessions and shared deadlines have brought us closer together, and I am thankful for their companionship. Lastly, I want to acknowledge the numerous challenges and setbacks I encountered during this research.
It is through perseverance and determination that I was able to overcome these obstacles. I commend myself for not giving up on life and staying committed to the completion of this thesis. Without the support and contributions of these individuals and my personal resolve, this thesis would not have been possible. I am sincerely grateful to all who have been a part of this journey and have contributed to its success.
TABLE OF CONTENT PLEDGE. ii TABLE OF CONTENT. i LIST OF TABLES. i LIST OF FIGURES.
ii LIST OF ACRONYMS. The necessity of the research. Climate-risks in Vietnamese Mekong River Delta. Cropping pattern in Vietnamese Mekong River Delta.
Sustainable cropping methods in Vietnamese Mekong River Delta. Scope of the research. Research questions and hypotheses. The framework of the research.
DATA AND METHODS. Remote sensing data collection and analysis. Ground truth observation. Desk review method.
Non-structured interview. Cropping pattern changes in Vietnamese Mekong River Delta. Cropping pattern changes adapting to climate risks. Cropping pattern changes adapting to floods.
Cropping pattern changes adapting to other climate risks. DISCUSSIONS AND RECOMMENDATIONS. Assessing the cropping pattern changes’ efficiency. Problems with triple cropping pattern.
Limitations and future outlooks. 68 LIST OF TABLES Table 1-1: Comparison between costs and benefits of intensified and balanced cropping in An Giang and Dong Thap, respectively. 13 Table 1-2: Explanation for sustainable cropping practice approaches in VMRD. 14 Table 1-3:Researching questions and hypotheses.
15 Table 1-4: Approved agriculture development plan in VMRD period of 2011-2025. 20 Table 2-1: IGBP classification scheme and RGB color code for LULC map. 26 Table 2-2: MODIS data acquisition date table. 27 Table 2-3: GTO field trip schedule in VMRD (March 2023).
31 Table 2-4: EVI accuracy assessment of Tra Vinh province points. 33 Table 2-5: Accuracy assessment of An Giang province points. 34 Table 2-6: Heading dates accuracy assessment of Tra Vinh province points. 35 Table 2-7: Heading dates accuracy assessment of An Giang province points.
36 i LIST OF FIGURES Figure 1-1: Flooding period by percentage of area in VMRD from 2000 to 2022 (GIS data). 5 Figure 1-2: Provincial flood and salinity risk in VMRD. 6 Figure 1-3: Typology and short definitions of the cropping system components. 8 Figure 1-4:Dikes and planted area of crops in An Giang from 1985-2016.
11 Figure 1-5: Dike construction: low and high dikes area in An Giang province in 2011 and 2014. 12 Figure 1-6: VMRD administrative map. 18 Figure 1-7: 3 ecological sub-regions for agricultural development plan in VMRD 20 Figure 1-8: SWI leading to soil salinity map with the depth from 0 cm to 20 cm in Tra Vinh province, VMRD, VN. 22 Figure 1-9: An Giang and Tra Vinh in administrative map.
23 Figure 1-10: Dike area in An Giang Province, VN, in 2014. 23 Figure 1-11: The logical framework of the research. 24 Figure 2-1: EVI spectral viewer. 29 Figure 2-2: GTO in VMRD route (blue line).
31 Figure 2-3: GTO validation process from 1 point. 32 Figure 2-4: GTO route in Tra Vinh and An Giang (pictures for each location are attached and can be accessed via Google Earth). 33 Figure 2-5: The example of rice growth stages and other rice field conditions in the paddy field area. 34 Figure 3-1: LULC maps from 2001 to 2021 in VMRD.
39 Figure 3-2: LULC change in VMRD from 2001 to 2021 (GIS data). 40 Figure 3-3: Differences in planted area of paddy by provinces in the whole period from 2001 to 2021 (statistical data). Error! Bookmark not defined. Figure 3-4: Map of changes in planted area of paddy in VMRD by provinces from 2001 to 2021 (statistical data).
41 Figure 3-5: Cropping frequency changes in VMRD from 2000 to 2022. 43 Figure 3-6: Yearly cropping frequency in VMRD from 2000 to 2022 (GIS data). 43 Figure 3-7: Maps of the number of flooding days in An Giang province from 2008 to 2015. 45 Figure 3-8: Maps of cropping frequency in An Giang province from 2008 to 2015 46 Figure 3-9: Cropping frequency changing trend in An Giang province from 2010 to 2015 (GIS data).
47 Figure 3-10: Production of paddy in An Giang from 2010 to 2015 (statistical data). 48 Figure 3-11: LULC maps in Tra Vinh from 2001 to 2021. 49 ii Figure 3-12: Number of inundated days yearly in Tra Vinh and An Giang from 2000 to 2022. 50 Figure 3-13: Planted area for paddy in Tra Vinh province from 2001 to 2021 (statistical data).
51 Figure 3-14: Cropping frequency in Tra Vinh province from 2000 to 2022 (GIS data). 52 Figure 3-15: Cropping frequency maps in Tra Vinh province from 2000 to 2022. 52 Figure 4-1: Yield of spring, autumn & winter paddy by provinces in VMRD from 2001 to 2014 (statistical data). 54 Figure 4-2: Paddy and orange intercropping in Tra Vinh Province (GTO).
57 Figure 4-3: Lotus pond combined with paddy field in Long An Province (GTO). 57 Figure 4-4: Inefficient paddy fields transformed into land for installing solar power panels in An Giang Province (GTO). 58 Figure 4-5: Advertisement material for sustainable agriculture approach in VMRD: 3 reductions 3 gains (left), and 1 must-do 5 reductions (right). 59 iii LIST OF ACRONYMS CC : Climate change CS-MAP : Climate-Smart Mapping and Planning DOY : Date of year GIS : Geographic Information System GTO : Ground truth observation LULC : Land use and land cover MODIS : Moderate Resolution Imaging Spectroradiometer SWI : Saline water intrusion VMRD : Vietnamese Mekong River Delta VN : Vietnam iv CHAPTER 1.
The necessity of the research Vietnam (VN) is located on the East Sea of the Pacific Ocean with a long coastal line at more than 3,000 km of coastline and is among the most vulnerable countries to the impact of climate change (CC). In reality, VN has been through many hostile phenomena of CC in recent years, including sea level rise, temperature increase, and intensified and more frequent hydro-climatic disasters (Cruz, 2007). This can be attributed to the country's location, long coastal line, and complex hydrological system. Provided that the economy relies heavily on agriculture, this sector accounts for over 12% of the national GDP and 24 million employment (Nguyen et al.
In 2021, the rice production in VN was approximately 43.9 million metric tons, and it is one of the biggest rice exporters in the world (Nguyen & Scrimgeour, 2022). Accounting for more than 50% of the nation's rice yield (Nguyen et al., 2022), the Vietnamese Mekong River Delta (VMRD) is one of the deltas cultivated most intensively worldwide. However, this region is vulnerable to climate change and disasters because of its low- lying landform. According to Intergovernmental Panel on Climate Change (IPCC) report, the climate risks for agriculture are rising temperature, changing rainfall, acidification increase, lack of oxygen, sea-level rise, extreme events, increased storms, and cyclones, droughts, and floods, increased climate variability (Intergovernmental Panel on Climate Change (IPCC), 2014).
The MRD also faces several climate risks, including rising sea levels and exacerbating flooding phenomena, which also lead to saltwater intrusion (SWI) in MRD, along with droughts and limited availability of freshwater. The VMRD is most affected by flooding and inundation. The harvest of rice is reasonably susceptible. In a report from (Nguyen et al., 2007), local farmers blame either inadequate flood control systems or damaged crops for low yields or crop losses and claim that flooding has practically become an annual occurrence.
Many places 1 along the central and north-central coasts are prone to flooding with strong currents. These pose a threat to property, human life, irrigation systems, and public infrastructure and are made worse by dyke breaches, strong winds, and sea waves. Farmers with homes or farms close to the seaside are at risk from storm-caused sea surges (Nguyen et al. Another significant problem in VMRD is SWI.
The SWI issue stems from the Mekong River's tidal level is lower than the high tide at sea, causing the river's flow to invert with the tides and bring water inland (Thuy & Anh, 2015). Salinity and erosion issues would also result from this. Sea water travels 70 kilometers inland during the dry season (Noh et al. This problem can potentially alter the spatial organization or configuration of the landscape because salinity can change the properties of water and soil components of the pattern, corrupt the flow of nutrients, and negatively affect rice farming in the area because rice has a low salinity tolerance.
In the VMRD, a dynamic and interdependent relationship exists among climate risks, land use and land cover (LULC) change, and cropping pattern changes. These factors are intricately linked and influence one another in complex ways. Climate risks, such as floods and SWI, can significantly impact LULC change in the region. Changes in LULC, such as land erosion from the sea-level rise or conversion of agricultural land, can, in turn, affect the local climate and exacerbate climate risks.
Additionally, changes in cropping patterns, such as shifts from traditional rice cultivation to other crops or cropping systems, can be influenced by both climate risks and land-use changes. These changes in cropping patterns can have implications for agricultural productivity, food security, and the overall sustainability of the VMRD. Therefore, understanding and managing the dynamic interactions among climate risks, LULC change, and cropping pattern changes is crucial for sustainable development and adaptation strategies in the VMRD. With the importance and vulnerability of MRD's agriculture, it is necessary to understand the climate risks and how to cope with them by more resilient cropping practices.