In this work, a new approach to using NDVI as a predictor of water quality parameters in arid environments is proposed. Our focus was the Araçuaí river basin, which has a predominance of native cerrado vegetation and is subject to seasonal variations in rainfall and vegetation cover. MODIS images (MOD13Q1) from 2000 to 2018 were used to calculate the NDVI of the contributing areas of the water quality monitoring stations and to analyze its relationship with fourteen water quality parameters. The NDVI showed significant seasonality, with high values in the rainy season, and temporal trends of increase in stretches related to the main river. A strong and new relationship was observed between NDVI and six water quality parameters: color, total dissolved solids, total suspended solids, total solids, nitrate and turbidity, this being stronger at the local scale, with better performance at from models that use incremental NDVI, capturing local variations in vegetation cover, instead of regional NDVI, which reflects the general state of vegetation. The results demonstrate the potential of using these indices to develop and improve prediction models of water quality parameters in river basins and to expand the spatial and temporal coverage of water quality monitoring.

在这项工作中，提出了一种使用NDVI作为干旱环境中水质参数预测因子的新方法。我们的重点是阿拉苏伊河流域，该流域以原生塞拉多植被为主，降雨量和植被覆盖度会受到季节变化的影响。利用2000-2018年MODIS影像（MOD13Q1）计算了水质监测站贡献区的NDVI，并分析了其与14个水质参数的关系。NDVI表现出明显的季节性，雨季数值较高，且与主要河流相关的河段随时间呈增加趋势。在 NDVI 和六个水质参数之间观察到一种强大的新关系：颜色、总溶解固体、总悬浮固体、总固体、硝酸盐和浊度，这种关系在局部范围内更强，并且使用增量 NDVI 的模型具有更好的性能，捕获植被覆盖的局部变化，而不是反映植被总体状况的区域 NDVI。结果表明，利用这些指数开发和改进流域水质参数预测模型以及扩大水质监测的时空覆盖范围具有潜力。