NGHIÊN CỨU ĐÁNH GIÁ VÀ DỰ BÁO TÁC ĐỘNG DO THIÊN TAI ĐẾN TRỒNG TRỌT TRÊN ĐỊA BÀN TỈNH NGHỆ AN CÓ XÉT ĐẾN YẾU TỐ BIẾN ĐỔI KHÍ HẬU tt

MINISTRY OF EDUCATION AND TRAINING MINISTRY OF AGRICULTURE AND RURAL DEVELOPMENT THUYLOI UNIVERSITY DANG VAN THANH QUANTIFICATION AND FORECAST OF THE IMPACTS OF NATURAL DISASTERS ON CROP PRODUCTION IN NGHE AN PROVINCE TAKING INTO ACCOUNT THE EFFECTS OF CLIMATE CHANGE Major: Water resources engineering Code: 9580212 SUMMARY OF DOCTORALTHESIS HANOI, 2022 The thesis is completed at: THUYLOI UNIVERSITY ACADEMIC SUPERVISORS: DR DO VAN QUANG ASSOC PROF DR LE VAN CHIN PGS.TS NGUYỄN CẢNH THÁI TS NGUYỄN CÔNG THẮNG Reviewer 1: Dr Le Hung Nam Reviewer 2: Assoc Prof Dr Nguyen Thi Minh Hien Reviewer 3: Assoc Prof Dr Nguyen Tuan Anh The thesis will be defended in front of a PhD thesis committee at the Thuyloi University Address: No 175 Tay Son - Dong Da District - Hanoi Time: 14:00 July 6th, 2022 Full version of the thesis is available at: - National Library of Vietnam (Hanoi) - Library of Thuyloi University INTRODUCTION Rationale of the study Impacts of natural disasters, such as storms, droughts and salinity, on the daily life of peopleall over the world have become increasingly severe The erratic changes in the frequency and intensity of natural disasters have caused heavy socio-economic losses and damages to many countries around the world Furthermore, the impacts of climate change have been considered one of the great challenges to many countries for decades Widespread changesin weather patterns, particularly the emergence of extreme weather events such as prolonged heatwave and heavy rainfall has been posing gravely negative impacts on crop production, the environment and daily life of human beings at a global scale Vietnam - a Southeast Asian country with a long coastline, has been affected by different types of natural disasters which often occur unexpectedly alongside climate-driven disasters (e.g.rising temperature, heat waves, heavy rainfall) Therefore, Vietnam has become one of the most vulnerable countries to suffer from the impacts of climate change Nghe An province has always been subject to severe effects caused by natural disasters and climate change In 2020, its economic loss was estimated at 1,327.019 billion VND In particular, a loss of 250.12 billion VND was caused by thunderstorm, whirlwind, thunder and hail; 141.053 billion VND by storms; 149.349 billion VND by a long period of raining from October 15 to October 20; and 786.497 billion VND by the storm No.9 Among the sufferers of climate change, local residents are certainly the most affected, especially those whose livelihoods are dependent on agriculture For the above reasons, the author has chosen an attention-grabbing research topic - “Quantification and forecast of the impacts of natural disasters on crop production in Nghe An province taking into account effects of climate change” which is of profound importance and significance Research objectives 1) Applying Ricardo model for cross-sectional data to quantify economic losses caused by natural disasters (storms, droughts, salinity) on crop production; Forecasting the losses caused by natural disasters on crop production in Nghe An taking into account different climate change scenarios (changes in temperature and precipitation) 2) Applying a multivariable regression model to quantify the impacts of adaption measures on farm revenues of farm houesholds in Nghe An province Research subject and scope of the study 3.1 Research subject Research subject: the impacts of natural disasters and climate change on crop production Data analysed in the study was collected from farm households and state management agencies on agriculture in Nghe An province 3.2 Scope of the study - In terms of content: Quantifying the of impacts of natural disasters (including storms, droughts and salinity) on crop production, taking into account effects of climate change (changes in temperature and the amount of rainfall); Analysing the impacts of measures adopted by farm households in response to natural disasters and climate change in Nghe An province Details are as follows: + Quantifying the impacts of natural disasters on crop production (rice, tea, orange) in Nghe An province, taking into account effects of climate change during the period from 2001 to 2020 + Quantifying the impacts of measures adopted by farm households in response to natural disasters in Nghe An province + Forecasting the impacts of natural disasters and climate change on crop production with respect to different climate change scenarios specified by Ministry of Natural Resources and Environment In this respect, only two scenarios are considered: average scenario of RCP 4.5 and high effect scenario of RCP 8.5, and without the scenario of RCP 2.6 scenario + Assessing measures adopted by farm households and proposing solutions for mitigating negative impacts of natural disasters and climate change in Nghe An province - In terms of time and temporal research: + Secondary data were collected during the period from 2001 to 2020 + Primary data were collected directly from farm households in the survey conducted in Nghe An in 2020 Research approaches and methods 4.1 Research approaches In order to achieve the research objectives, the author has synthesised and revieweda broad range of both domestic and international studies A number of results from these studies have been inherited and integrated into this research, making sure that the research is suitable for the case of Vietnam 4.2 Research methods There are various research methods applied in this study, including the mixed method (combining quantitative and qualitative research methods), inheritance method; statistical method; survey method (used for designing questionaires and gathering primary data); data systhesis and analysis method; expert consultation; quantitative research method Theoretical framework Scope of the study and Research subject Research models Impacts of natural disasters (storms, droughts, salinity) on crop production in Nghe An taking into account effects of climate Ricardo model (crosssectional change Linear regression model using OLS method Results Quantifying and forecasting the impacts of natural Assessing the impacts of adaptation measures Figure 0.1 Theoretical framework Proposing solutions Mitigating the impacts of natural disasters and climate change on crop production Significance of the study 6.1 Scientific significance of the study Results of this study will contribute to the theoretical basis for research on crop production losses due to natural disasters in the context of climate change Assessment and quantification of crop production lossescaused by natural disasters (storms, droughts and salinity) in the context of climate change will be the basis for proposing proper policies, contributing to improving socio-economic efficiency of the prevention, control and forecast on the impacts of natural disasters and climate change on crop prodcution in Nghe An province 6.2 Practical significance of the study Results of this study can be used as a valuable reference source to improve efficiency of management activities in forecasting, preventing and tackling the impacts of natural disasters in the context of climate change in Nghe An province These findings will be good references for policy makers and scientists to propose better policies Structure of the thesis The thesis is structured into chapters in addition to the Introduction and Conclusion CHAPTER THEORETICAL BASIS AND LITERATURE REVIEW OF THE IMPACTS OF NATURAL DISASTERS AND CLIMATE CHANGE ON CROP PRODUCTION 1.1 Theoretical basis 1.1.1 Definitions on agricultural production and crop production 1.1.2 Impacts of natural disasters on crop production 1.1.2.1 Definition of natural disasters The definition of natural disasters is according to Clause 1, Article of the Law on Natural Disaster Prevention and Control No 33/2013/QH13 dated 19/6/2013 by the National Assembly 1.1.2.2 Impacts of natural disasters on crop production Natural disasters have been subtanstively affecting production activities of households, businesses as well as the economy as a whole There are 21 different types of natural disasters and they have different impacts on different groups of people or businesses 1.1.3 Impacts of climate change on crop production 1.1.3.1 Definition of climate change 1.1.3.2 Causes of climate change 1.1.3.3 Impacts of climate change on crop production 1.1.3.4 Climate change scenarios in Vietnam 1.2.1 Literature review on the impacts of natural disasters and climate change on crop production Research conducted by Olesen (2011), Mohamed (2012) and Alistair Hun (2007) showed that natural disasters have huge impacts on the economy of various nations, especially in terms of crop production Both qualitative and quantitative methods have been used in their studies to quantify impacts of natural disasters and climate change In Vietnam, many scholars also have conducted research on the impacts of natural disasters and climate change, including Phan Thi Cam Hang (2015),Tran Dai Nghia (2015),Nguyen Thi Thu Thuy (2018); Nguyen Hoang Son (2020),Le Sam et al (2008) and Nguyen Tuan Anh (2012) However, no ones had applied econometric models to analyse impacts of natural disasters and climate change on crop production 1.2.2 Literature review on research methods used to quantify the impacts of natural disasters and climate change on crop production Agriculture is considered the most sensible sector toward the impacts of climate change This has been proven in variousstudies which show that natural disasters and climate change have caused massive losses and damages to farming and animal husbandry sectors (Deschenes, 2007; Mendelsohn, 1994; Adam et al, 1998; Banerjee, 2010) Ricardo model is often used in assessing the impacts of natural disasters and climate change on a specific sector In Vietnam, scientists started undertaking studies on natural disasters and climate change decades ago (Nguyen Duc Ngu, 1991; Nguyen Trong Hieu and Dao Duc Tuan, 1993; Nguyen Trong Hieu andTran Viet Lien, 2000) However, domestic studies using economic approaches generally adopt quantitative method, statistical method and cost-benifit analysis but fail to successfully apply Ricardo model with variables representing natural disasters (storms, droughts, salinity) and climate change (amount of rainfall and temperature) 1.2 International experiences in respondingto natural disasters and climate change Experience from Netherland, China, South Korea and Japan 1.3 Research gaps 1.3.1 Research gaps in terms of contents Most existing literature focuses on the impacts of either natural disasters (storms, droughts, salinity) or climate change (changes in amount of rainfall and temperature) on agricultural production, construction, urban infrastructure etc There are a few studies that take into account both natural disasters and climate change The studies, however, consider only the impacts of storms and the amount of rainfall There has been no research on the impacts of natural disasters (including storms, droughts, salinity), taking into account the effects of climate change (changes in the amount of rainfall and temperature) Storms, droughts and salinity occur with high frequency in Vietnam Furthermore, the situation can be worsened by effects of climatedriven extreme events such as heat waves and heavy rainfall, causing massive economic losses and fatalities Therefore, research on the impacts of natural disasters (storms, droughts, salinity), taking into consideration the effects of climate change (changes in the amount of rainfall and temperature) is necessary and would be benificial to the development of science and the society in general 1.3.2 Research gap in terms of research site The author has noticed that so far there has been no research on the impacts of natural disasters and climate changeon crop farming as well as quantification of losses and damages caused by natural disasters and climate change in Nghe An province Therefore, the chosen research topic is necessary and has not been studied in Vietnam 1.4 Introduction to the research site 1.4.1 Selection of research site Nghe An province is located in North Central Vietnam with the largest area and the fourth largest population in the country The province has plentiful and diversified natural resources and is considered a small image of the country 1.4.2 Selection of research subject 1.4.2.1 Reasons for choosing crop farming sector Crop farming is critical to Vietnam’s agricultural industry Indeed, it provides food and and raw materials for the processing industry and major export commodities for Vietnam In Vietnam, crop production accounts for 75% of the total national agricultural production According to data provided by the General Statistics Office of Vietnam in 2020, farm households made up more than 70% of the total population of Nghe An province Therefore,farm households have been interviewed in order to collect primary data for the research According to a report by Nghe An Department of Agriculture and Rural Development and data published by the General Statistics Office of Vietnam in 2020, rice producing area made up 51.2% of total cultivated land area;orange growing area made up 57.6% of total fruit farming area; orange output accounted for 51.5% of total production of fresh fruit; tea growing area made up 76.3% of total area for perennial plants; tea output accounted for 95.5% of total output of perennical plants Therefore, rice, orange and tea crops have been chosen for the research purposes as they represent annual plants, perennial fruit plants and industrial perennial crops respectively 1.4.2.2 Reasons for selecting the subjects for studying on the impacts of natural disasters and climate change Nghe An has been suffering from storms, floods and droughts; however, storms and floods often occur simultaneously and hence, within the scope of this study, only storms are examinedalongsidedroughts Additionally, high-salinity concentration has become increasingly common in recent years and siginificantly affected the daily life of local people Therefore, salinity is also examined in this study It is clear that the two main factorscontributing toeconomic losses in Nghe An over the past 10 years are changes in the amount of rainfall and temperature Therefore, these two factors are taken into account when measuring the impacts of climate change 1.5 Research outcomes - Complement to the theretical basis on the impacts of natural disasters and climate change on crop production - Application of econometric models and methods to assess and quantify the impacts of natural disasters (storms, doughts, salinity) on crop production in Nghe An province, taking into account effects of climate change -Forecast of the impacts of natural disasters and climate change on crop production with respect to differentclimate change scenarios provided by Ministry of Natural Resources and Environment in 2016, including RCP 4.5 and RCP 8.5 scenarios - Analysis of the impacts of measures adopted by farmers in response to natural disasters in Nghe An province, using economic models - Provision of policy recommendations aimed to prevent, mitigate and tackle impacts of natural disasters and climate change in Nghe An province 1.6 Conclusions of chapter Literature review on the impacts of natural disasters and climate change has been presented with 10 domestic studies and international studies It is noticed that there has not been a proper study on impacts of natural disasters and climate change on crop production in Vietnam using econometric models The author therefore has presented desired research outcomes as listed above CHAPTER RESEARCH METHODS 2.1 Selection of research methods and research process 2.1.1 Selection of research methods 2.1.1.1 Inheritance of data: The model applied to measure impacts of natural disasters and climate change on crop production is as below: LnY = β + ∑ β thientai + ∑ β dactrung + ∑ β bienphap + ∑ β Bdkh + ∑ β Bdkh + β lua + β tuongtac + μ (2.5) The independent variables are as follows: - Variables representing natural disasters (thientai ) b:  Storms: number of storming days (Ngaybao ), intensity of storms (Cuongdobao )  Droughts: Sazonov index (Sa.I) (Han ) 2.2.3 Research methods to measure the impacts of natual disasters and climate change with respect to different climate change scenarios Climate change scenarios: According to Ministry of Natural Resources and Environment, two climate change scenarios (RCP 4.5 and RCP 8.5) are considered Formula for measurement of economic losses: W=∑ [ ( 1) − ( 0)] (2.6) 2.3 Models used to assess the impacts of the measures adopted by households in response to natural disasters and climate change 2.3.1 Multivariable regression model using OLS method Yi = β0 + β1Di + β2Xi + εi (2.7) 2.3.2 Experimental model used to assess the impacts of the measures adopted by households in response to natural disasters and climate change The model is applied to cross-sectional data analysis Details are as follows: _ ℎ ℎ = +∑ ℎ +∑ ℎ + (2.8) 2.4 Conclusions of chapter The author has presented the survey method, the collection of primary and secondary data, the data sources, the systhesis of data and how data was cleaned and prepared for analysis.The Ricardo model and the multivariable regression model with OLS method have also been clearly presented 11 CHAPTER CURRENT STATUS, QUANTIFICATION AND FORECAST OF THE IMPACTS OF NATURAL DISASTERS ON CROP PRODUCTION, TAKING INTO ACCOUNT EFFECTS OF CLIMATE CHANGE 3.1 Current impacts of natural disasters and climate change on crop production 3.2 Assessment and forecast of impacts of natural disasters on crop production taking into account the effects of climate change 3.2.1 Assessment of impacts of natural disasters on crop production taking into account effects of climate change Table 3.9 Results of regression analysis of the impacts of natural disasters on crop revenue Variable gioitinh Tuoi Trinhdo quymoho Han Ngaybao Cuongdobao Man lua Bp_man Bp _han Natural disasters Without response With response measures measures 0.206*** 0.195*** (0.0585) (0.0581) 0.00715*** 0.00755*** (0.00243) (0.00241) 0.0547 0.0627 (0.0473) (0.0476) 0.0314 0.0288 (0.0192) (0.0191) -8.377*** -7.462*** (0.976) (0.988) -0.166*** -0.152*** (0.0570) (0.0567) -0.102** -0.0859** (0.0397) (0.0395) -1.359*** -1.298*** (0.147) (0.146) 0.190 0.0751 (0.413) (0.408) 0.0656 (0.0735) 0.238*** (0.0634) 12 Variable Bp_ bao Constant Observations R-squared Natural disasters Without response With response measures measures 0.128* (0.0672) 30.23*** 27.98*** (1.750) (1.808) 531 531 0.868 0.872 The value in the brackets () is the standard error; The significance: *** p