Groundwater is a vital resource in the northern region of Sri Lanka, as it is the only water resource used for domestic, agricultural and industrial activities in that area. However, due to excessive usage of synthetic fertilizer, the groundwater in this part of the country is highly contaminated with nitrates. In addition, due to the effect of underlain limestone aquifer, water hardness is also high. The present study aimed to study the effect of filtration through Terminalia arjuna mature leaf powder and Phyllanthus emblica bark powder on reducing nitrate concentration and hardness. The results indicated that 21.4% reduction of nitrate concentration can be achieved by filtration through Terminalia arjuna mature leaf powder and 9.3% reduction of total hardness by filtration through Phyllanthus emblica bark powder. Therefore, further research is recommended on testing the potential and side effects of using Terminalia arjuna mature leaf powder and Phyllanthus emblica bark powder as a combined home remedial treatment technique for treating nitrate contaminated hard water.

中文翻译：

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榄仁成熟叶粉和余甘子树皮粉对岩溶石灰岩含水层中的硝酸盐：N和地下水总硬度的功效

地下水是斯里兰卡北部地区的重要资源，因为它是该地区唯一用于家庭，农业和工业活动的水资源。然而，由于过度使用合成肥料，该国该地区的地下水被硝酸盐高度污染。另外，由于底层石灰岩含水层的作用，水硬度也很高。本研究旨在研究通过榄仁木成熟叶粉和余甘子树皮粉末进行过滤对降低硝酸盐浓度和硬度的影响。结果表明，通过榄仁进行过滤可降低硝酸盐浓度21.4％成熟的叶子粉末，通过余甘子树皮粉末过滤可降低总硬度9.3％。因此，建议进一步研究，以测试使用榄仁成熟叶粉和余甘子树皮粉作为家庭综合处理技术来处理硝酸盐污染的硬水的潜力和副作用。