Showing papers by "Badronnisa Yusuf published in 2021"

Assessment of Streamflow Simulation for a Tropical Forested Catchment Using Dynamic TOPMODEL—Dynamic fluxEs and ConnectIvity for Predictions of HydRology (DECIPHeR) Framework and Generalized Likelihood Uncertainty Estimation (GLUE)

Abstract: Rainfall runoff modeling has been a subject of interest for decades due to a need to understand a catchment system for management, for example regarding extreme event occurrences such as flooding. Tropical catchments are particularly prone to the hazards of extreme precipitation and the internal drivers of change in the system, such as deforestation and land use change. A model framework of dynamic TOPMODEL, DECIPHeR v1—considering the flexibility, modularity, and portability—and Generalized Likelihood Uncertainty Estimation (GLUE) method are both used in this study. They reveal model performance for the streamflow simulation in a tropical catchment, i.e., the Kelantan River in Malaysia, that is prone to flooding and experiences high rates of land use change. Thirty-two years’ continuous simulation at a daily time scale simulation along with uncertainty analysis resulted in a Nash Sutcliffe Efficiency (NSE) score of 0.42 from the highest ranked parameter set, while 25.35% of the measurement falls within the uncertainty boundary based on a behavioral threshold NSE 0.3. The performance and behavior of the model in the continuous simulation suggests a limited ability of the model to represent the system, particularly along the low flow regime. In contrast, the simulation of eight peak flow events achieves moderate to good fit, with the four peak flow events simulation returning an NSE > 0.5. Nonetheless, the parameter scatter plot from both the continuous simulation and analyses of peak flow events indicate unidentifiability of all model parameters. This may be attributable to the catchment modeling scale. The results demand further investigation regarding the heterogeneity of parameters and calibration at multiple scales.

Flood Impacts across Scales: towards an integrated multi-scale approach for Malaysia

Abstract: Flooding is a recurring challenge across Malaysia, causing loss of life, extensive disruption and having a major impact on the economy. A new collaboration between Malaysia and UK, supported by the Newton-Ungku Omar Fund, aims to address a critical and neglected aspect of large-scale flood risk assessment: the representation of damage models, including exposure, vulnerability and inundation. In this paper we review flood risk and impact across Malaysia and present an approach to integrate multiple sources of information on the drivers of flood risk (hazard, exposure and vulnerability) at a range of scales (from household to national), with reference to past flood events. Recent infrastructure projects in Malaysia, such as Kuala Lumpur’s SMART Tunnel, aim to mitigate the effects of flooding both in the present and, ideally, for the foreseeable future. Our collaborative project aims to develop and assess a new multi-scale model of flood risk in Malaysia for current and projected future scenarios, and to address climate adaptation questions of policy relevance for flood stakeholders. This approach will enable us to identify the preferred adaptation pathways given multiple scenarios of climate and socio-economic change in Malaysia, and, beyond the life of our project,

Former and Current Trend in Subsurface Irrigation Systems

Abstract: The main purpose of this review is to find the diversity in research studies of subsurface irrigation systems in the past two decades. Two periods of five years were selected to reflect the research studies at the beginning and the end of the comparing periods range. A statistical sorting was used to investigate the distribution of papers according to objectives, types of irrigation systems, research methods, and limitations of the studies. Results showed that the measurements and evaluations were the most presented objectives of the selected papers for both periods. Furthermore, almost 90 percent of the recent papers used multiple research methods, unlike the papers published in the former period which only 56 percent of them used multiple methods. Also, more than 90 percent of the recent papers used a single irrigation system. In conclusion, knowledge of subsurface irrigation systems had been advanced in the former studies mostly by analyzing the measurements and evaluations of the traditional irrigation systems. Unlike the former period, the advancement in knowledge has been produced in the current period by introducing new subsurface irrigation systems and more concentration by the order of measurements, evaluation, and designing, respectively.

Features and Geomorphic Response of Mountainous River by Reach Scale

Abstract: Many activities such as hard engineering control measures have made the river out of natural rivers. The loss of physical and biological function in altered river have induced large scale adverse response by the public throughout Malaysia. Therefore, an understanding of river’s equilibrium characteristics is important for managing the quality of river in mountainous catchment area. The aim of this study is to investigate the features and geomorphic response of mountainous river. The method of data collection is by extensive fieldwork including measuring the river geometry, hydraulics properties, sediment load characteristics, and size of bed materials at reach scale. This research is significant for managing the quality of water resources in Malaysia where most of it is located at mountainous area. The criteria presented by morphology and the geomorphic response that occurs along the river reach has proven that the river is in equilibrium condition.