Studies done on small tropical west-flowing river catchments located in the Western Ghats in southwestern India have suggested very intense chemical weathering rates and associated CO₂ consumption. Very less studies are reported from these catchments notwithstanding their importance as potential sinks of atmospheric CO₂ at the global scale. A total of 156 samples were collected from a small river catchment in the southwestern India, the Payaswini–Chandragiri river Basin, during pre-monsoon, monsoon and post-monsoon seasons in 2016 and 2017, respectively. This river system comprises two small rivers originating at an elevation of 1350 m in the Western Ghats in peninsular India. The catchment area is dominated by biotite sillimanite gneiss. Sodium is the dominant cation, contributing ~ 50% of the total cations, whereas HCO₃⁻ contributes ~ 75% of total anions. The average anion concentration in the samples varied in the range HCO₃⁻ > Cl⁻ > SO₄²⁻ > NO₃⁻ > F⁻, whereas major cation concentration varied in the range Na⁺ > Ca²⁺ > Mg²⁺ > K⁺. The average silicate weathering rate (SWR) was 42 t km⁻² y⁻¹ in the year 2016 and 36 t km⁻² y⁻¹ in 2017. The average annual carbon dioxide consumption rate (CCR) due to silicate rock weathering was 9.6 × 10⁵ mol km⁻²y⁻¹ and 8.3 × 10⁵ mol km⁻² y⁻¹ for 2016 and 2017, respectively. The CCR in the study area is higher than other large tropical river catchments like Amazon, Congo-Zaire, Orinoco, Parana and Indus because of its unique topography, hot and humid climate and intense rainfall.

对位于印度西南部西高止山脉的小型热带西流河流流域进行的研究表明，化学风化速率非常强烈，并伴随着 CO ₂消耗。尽管这些集水区作为全球范围内大气 CO ₂的潜在汇具有重要意义，但有关这些集水区的研究报告却非常少。分别在 2016 年和 2017 年季风前、季风和季风后季节，从印度西南部的 Payaswini-Chandragiri 河流域的一个小河流流域采集了总共 156 个样本。该河流系统由两条小河组成，发源于印度半岛西高止山脉海拔1350米。流域区以黑云硅线片麻岩为主。钠是主要的阳离子，约占总阳离子的 50%，而 HCO ₃ ⁻约占总阴离子的 75%。样品中的平均阴离子浓度变化范围为 HCO ₃ ⁻  > Cl ⁻  > SO ₄ ²⁻  > NO ₃ ⁻  > F ⁻，而主要阳离子浓度变化范围为 Na ⁺ > Ca ²⁺ > Mg ²⁺ > K ⁺ . 2016年平均硅酸盐风化率（SWR）为42 t km ^-2  y ^{-1 ，2017年为36 t km -2}  y ^{-1 。}硅酸盐岩风化导致的年平均二氧化碳消耗率（CCR）为9.6 2016年和2017年分别为× 10 ⁵  mol km ^-2 y ^-1和8.3 × 10 ⁵  mol km ^-2  y ^-1 。由于其独特的地形、湿热的气候和强降雨，研究区的CCR高于亚马逊、刚果-扎伊尔、奥里诺科、巴拉那和印度河等其他大型热带河流流域。