A study was conducted to identify the water quality status of Kelantan River Basin, Peninsular Malaysia, covering five sub-catchments (Nenggiri, Galas, Lebir, Pergau, and Kelantan downstream (DS)) during the dry and rainy seasons. Water samples were collected from 27 sampling stations along the Kelantan River at the years 2017 and 2018. The data consists of temperature, pH, total suspended solid (TSS), dissolved oxygen (DO), biochemical oxygen demand (BOD), chemical oxygen demand (COD), ammonia nitrogen (AN), nitrate (NO₃), phosphorus (P), and manganese (Mn). The water quality status was identified by calculating the water quality index (WQI) based on the National Water Quality Standards for Malaysia (NWQS) using six parameters. The study explores the spatial approach in assessing water quality status to produce an assessment index. Results showed that water quality status during the dry season at Kelantan River Basin was in class III for all sub-catchments, where the water can only be used for livestock drinking and tolerant species of fishes. Meanwhile, the quality of the water during the rainy season was in class III for the sub-catchments of Lebir, Pergau, and Kelantan DS. The Galas’ sub-catchment was in class IV, and the Nenggiri’s sub-catchment was experiencing the worse condition (in class V). Overall, the water quality in the Kelantan River Basin is at a moderate level, whereby more focus on the Nenggiri’s and the Galas’ sub-catchments should be take it seriously to ensure that the river water pollution levels in Kelantan are well under control.

进行了一项研究，以查明马来西亚半岛吉兰丹河流域的水质状况，涵盖了干燥和雨季的五个子集水区（Nenggiri，Galas，Lebir，Pergau和吉兰丹下游（DS））。在2017年和2018年，从吉兰丹河沿岸的27个采样站采集了水样。数据包括温度，pH，总悬浮固体（TSS），溶解氧（DO），生化需氧量（BOD），化学需氧量（COD），氨氮（AN），硝酸盐（NO ₃），磷（P）和锰（Mn）。根据马来西亚国家水质标准（NWQS），使用六个参数计算水质指数（WQI），从而确定水质状态。该研究探索了评估水质状况以产生评估指标的空间方法。结果表明，吉兰丹河流域干旱季节所有子集水区的水质状况均为III类，这些水只能用于牲畜饮水和耐性鱼类。同时，雨水的水质在Lebir，Pergau和Kelantan DS的子汇水区处于III类。Galas的子汇水处在IV级，而Nenggiri的子汇水处在更恶劣的条件下（V类）。总体，