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Flood Risk Estimation of Paddy Production Considering Plants’ Age and Flood Durations
Abstract
Floods pose serious threats worldwide. During this disaster, civil engineering structures, such as buildings, bridges, dams, water supply, coastal structures, infrastructure facilities are severely affected, causing immense inconvenience to people and disrupting routine life. In the context of water-food security, floods have been a major source of natural disturbance to rice productivity in Malaysia. The consequences of floods will bring losses to the rice production and cause instability. The damage of paddy production due to floods needs to be handled seriously as the negative impact could lead to insufficient food supplies in the country. The purpose of this paper is to estimate flood risk in paddy production considering different flood inundation durations and plant’s ages. The calculation of risk considers the probability of extreme flood levels and fine cell resolution of paddy field in the total loss estimation. The location used for this study is in Kedah, where rice production is among the most prominent in Malaysia. Flood risk is expected mounting to nearly half a million ringgits for the 330 ha plots considering the current condition. This emphasize on an effective long-term flood risk management in order to reduce flood risk to paddy production.
... Even though the cultural and culinary of glutinous rice in Malaysia are vital, its cultivation faces significant challenges. These include unsustainable land-use practices (Dorairaj & Govender, 2023), labor shortages (Abdullah, 2023;Adnan et al., 2018), limited resources (Abdullah, 2023;Sheikhy Narany et al., 2017), and high production costs (Dorairaj & Govender, 2023;Rehan et al., 2020). Addressing these issues through focused research and strategic interventions is crucial for ensuring the sustainability of glutinous rice production in Malaysia. ...
... Despite government interventions such as subsidy schemes and cultivation projects, several significant endogenous factors continue to challenge the productivity of glutinous rice crops in Malaysia. Key issues include labor shortages (Adnan et al., 2018;Hashim et al., 2024), limited natural resources (Hashim et al., 2024;Sheikhy Narany et al., 2017), and the high costs associated with production (Doraaj & Govender, 2023;Rehan et al., 2020). Additionally, the reliance on commercial fertilizer (Anisuzzaman et al., 2021;Dorairaj & Govender, 2023) further exacerbates these challenges. ...
The cultivation of glutinous rice remains limited in Malaysia which occupies less than four percent of the total rice-growing area in the country. In this regard, this study examines the complex dynamics of the glutinous rice system in Malaysia using a causal loop diagram (CLD) to understand the interactions between various factors like productivity, land use, population growth, and food security. To fulfill that, a CLD based on the system dynamics (SD) approach is developed to highlight the reinforcing and balancing loops that drive and constrain the system. In the developed CLD, the causal relationships are established by connecting the identified cause-and-effect variables. Subsequently, the causal signs are determined based on a positive (+) or a negative (–) sign to each relationship between variables. As a result, balancing loops illustrate that an increase in research and development (R&D), training, and government subsidies can enhance rice production, thereby improving food security and income levels. However, these benefits are tempered by a reinforcing loop that reflects the system’s limitations, which eventually curb sustainability glutinous rice production, particularly caused by the increasing Malaysian population. Furthermore, higher productivity and food security must be managed carefully to avoid over-exploitation of resources. The insights from this model are critical for policymakers to ensure the long-term sustainability of the glutinous rice sector while meeting the growing demand.
... For example, Giang and Trung Vy (2021) applied hydrology and inundation modelling from climate change scenarios and analysed the potential economic loss of rice production, but not to the extent of integrating the range of probable floods and the consequences. Meanwhile, Rehan and Idham (2020) quantified flood risk on rice production by taking a range of probable extremes but did not examine the effects of seasonal extremes variability. Attempts to estimate the seasonal flood risk of agricultural yield loss were pioneered by Forster et al. (2009) where they integrate the seasonal variation of crop cultivation periods into the analysis. ...
... Over the years, floods are known as one of the major threats to rice production with a cumulative area of more than 50 thousand hectares being inundated by floods between the year 2008 and 2017 in the northwest of Peninsular Malaysia. A micro-scale assessment of flood risk to paddy has shown that flood risk in expected annual damage can reach up to RM147,000 (around USD 33,325) for a 330-ha paddy granary area of Kedah, Malaysia [2]. This value may rise even higher if a larger paddy granary area were considered. ...
Information of flood damage to crops production is essential for guiding risk-based decisions in reducing future adverse impacts of floods. For paddy, its susceptibility to floods is one of the factors that may influence the loss of paddy’s production. To date, there have been limited studies that have been undertaken to examine in detail how different damage functions (with and without a susceptibility index) influence flood damage estimates of paddy using past recorded flood information. This study attempts to examine flood damage functions of different forms in two conditions: as their stand-alone forms and when being applied for damage and risk estimations. Furthermore, recorded revenues from the past were used to investigate the effects of paddy’s susceptibility to floods on revenues. Historical flood evidence and revenues between 1987 and 2021 occurred on paddy granaries under the Muda Agricultural Development Authority’s (MADA) monitoring located in Perlis and Kedah states of Peninsular Malaysia and were used in this study. Application of three damage functions reveals that the exclusion of susceptibility index from the damage calculation results in significantly overestimations of losses, with a standard deviation reaching as high as 38 and overestimations up to four times that of the function with susceptibility index. The high estimates could hinder the acceptance of risk-based flood assessment (and its results) in flood alleviation decision-making. Furthermore, as the percentage of flooded area increases, the revenue loss increases, indicating the effects of floods on harvested paddy quality. This further highlights the potential role of the susceptibility index in the damage function.
Dam-break floods cause substantial damage to the environment, and evaluating the negative impacts of dam-break floods on the environment (EI) is an important part of flood risk management. EI has been evaluated using various methods with different indices. However, the evaluation results of EI are typically one-sided or inaccurate because of diverse indices and complex influencing factors. A new method was proposed herein to calculate EI with an index system, including geomorphic changes (GC), water pollution (WP), plant biomass loss (PB), and biodiversity loss (BL). Eight factors that influence EI were sorted out, namely, erosion or deposition depth, non-point source (NPS) and point source (PS) pollution, plant biomass, species richness, plant height, and flood depth, velocity, and duration. After combining the proposed damage functions to calculate the influence of flood depth, velocity, and duration, and plant height on the environment, methods to calculate GC, WP, PB, BL, and EI were proposed. A dam-break flood scenario for Luhun Reservoir was used to verify the method. The results showed that (1) the trend in EI was similar to that in geomorphic changes in the inundated area and seriously affected by PS in local areas, (2) the average EI of woodland was the highest, while that of towns was the slowest, and (3) GC and WP contributed 93.7% of EI in the entire inundated area. This study summarized the complex impacts of dam-break floods on the environment from four aspects and proposed a method to quantify the overall impact of dam-break floods on the environment. The evaluation model could evaluate the impact of floods on the environment accurately, presenting the results on a flood inundation map. This provides a scientific basis for evaluating flood consequences and managing flood risk.
The aim of the article is to assess the variability of the risk of flood risk with the use of distributions maximum values. The copyright research is hydrological data in the form of daily water levels from the period 1981-2011. The collected data are derived from the hydrological station Bystrzyca Klodzka for the Nysa Klodzka river and the hydrological station Lesna for the Kwisa river. For the purpose of estimating flood risk from the collected data has been selected quarterly maxima of daily water levels. As a measure of the flood risk authors accepted the likelihood of exceeding the alarm condition in the test sections of the rivers. This risk is calculated by using the theoretical cumulative distribution distribution of quarterly highs water levels.
Economic damage assessment for flood risk estimation is established in many countries, but attentions have been focused on macro- or meso-scale approaches and less on micro-scale approaches. Whilst the macro- or meso-scale approaches of flood damage assessment are suitable for regional- or national-oriented studies, micro-scale approaches are more suitable for cost–benefit analysis of engineered protection measures. Furthermore, there remains lack of systematic and automated approaches to estimate economic flood damage for multiple flood scenarios for the purpose of flood risk assessment. Studies on flood risk have also been driven by the assumption of stationary characteristic of flood hazard, hence the stationary-oriented vulnerability assessment. This study proposes a novel approach to assess vulnerability and flood risk and accounts for adaptability of the approach to nonstationary conditions of flood hazard. The approach is innovative in which an automated concurrent estimation of economic flood damage for a range of flood events on the basis of a micro-scale flood risk assessment is made possible. It accounts for the heterogeneous distribution of residential buildings of a community exposed to flood hazard. The feasibility of the methodology was tested using real historical flow records and spatial information of Teddington, London. Vulnerability curves and residual risk associated with a number of alternative extents of property-level protection adoptions are estimated by the application of the proposed methodology. It is found that the methodology has the capacity to provide valuable information on vulnerability and flood risk that can be integrated in a practical decision-making process for a reliable cost–benefit analysis of flood risk reduction options.
Estimating the expected annual damage (EAD) due to flooding in an urban area is of great interest for urban water managers and other stakeholders. It is a strong indicator for a given area showing how vulnerable it is to flood risk and how much can be gained by implementing e. g., climate change adaptation measures. This study identifies and compares three different methods for estimating the EAD based on unit costs of flooding of urban assets. One of these methods was used in previous studies and calculates the EAD based on a few extreme events by assuming a log-linear relationship between cost of an event and the corresponding return period. This method is compared to methods that are either more complicated or require more calculations. The choice of method by which the EAD is calculated appears to be of minor importance. At all three case study areas it seems more important that there is a shift in the damage costs as a function of the return period. The shift occurs approximately at the 10 year return period and can perhaps be related to the design criteria for sewer systems. Further, it was tested if the EAD estimation could be simplified by assuming a single unit cost per flooded area. The results indicate that within each catchment this may be a feasible approach. However the unit costs varies substantially between different case study areas. Hence it is not feasible to develop unit costs that can be used to calculate EAD, most likely because the urban landscape is too heterogeneous.
Ricardian model was used to estimate the impact of climate change on granary level net revenue of paddy sector in Malaysia. Panel data from eight granaries was used in this study and the annual net revenue was regressed against climate variables and other controlled variables. The results indicate that climate is one of the determinants of Malaysian paddy granaries’ profitability. Given future predicted climate scenario indicates that farmers are predicted to lose an average of about 67% of revenue within the period of 2020 to 2029, 88% within 2050 to 2059, and 127% within 2090 to 2099. The losses might affect the livelihood of 296,000 paddy farmers in Malaysia. Thus, immediate adaptation strategies are critical in order to deal with such predicted effects.
Flooding is the major natural hazard that occurs in Malaysia. Flooding causes loss of lives, injuries, property damage and leave economic damage to the country, especially when it occurs in an agricultural area. There is still a lack of information available on floodplain especially on the impact of flooding in the agricultural area. This study focused on flooding and flooding impact in oil palm plantations, fruits and vegetables area. A river modeling is required to study the impact of flooding and to mitigate the floods using one mitigation option. A flood model was developed using InfoWorks Integrated Catchment Model (ICM) to carry out the analysis for flood damage assessment. With the aim of creating a flood damage map, Geographical Information System (GIS) was combined with the flood model to provide an ideal tool for the analysis of the flood damage and the effect of mitigation to flood damage. The estimated total damage for three different flood event; 10 ARI, 50 ARI and 100 ARI involved millions of ringgits. In order to reduce the flood impact along the Selangor River, a flood mitigation structure which is a retention pond was suggested, modeled and simulated. The effects of the retention ponds were analyzed and evaluated for 10 ARI, 50 ARI and 100 ARI. With this retention pond, flood extents of the flood events in agricultural area were shown capable of reduction significantly by 65.57% for 10 ARI, 76.18% for 50 ARI and 72.51% for 100 ARI.
Official Website Muda Agricultural Development Authority
- Mada
- Gov
Rice industry development program. Official Website Muda Agricultural Development Authority
- Mada
Flood damage assessment-literature review and recommended procedure. Cooperative Research Centre for Water Sensitive Cities
- L Olesen
- R Lowe
- K Ambjerg-Nielsen
Assessing the impact of extreme floods on agricultural in Vietnam: Quang Nam case study
- V N Chau
Malaysia flood: impacts & factors contributing towards the restoration of damages
- Z A Akasah
- S V Doraisamy