Agricultural runoff transports sediments and nutrients that deteriorate water quality erratically, posing a challenge to ground-based monitoring. Satellites provide data at spatial-temporal scales that can be used for water quality monitoring. PlanetScope nanosatellites have spatial (3 m) and temporal (daily) resolutions that may help improve water quality monitoring compared to coarser-resolution satellites. This work compared PlanetScope to Landsat-8 and Sentinel-2 in their ability to detect key water quality parameters. Spectral bands of each satellite were regressed against chlorophyll a, turbidity, and Secchi depth data from 13 reservoirs in Oklahoma over three years (2017–2020). We developed significant regression models for each satellite. Landsat-8 and Sentinel-2 explained more variation in chlorophyll a than PlanetScope, likely because they have more spectral bands. PlanetScope and Sentinel-2 explained relatively similar amounts of variations in turbidity and Secchi Disk data, while Landsat-8 explained less variation in these parameters. Since PlanetScope is a commercial satellite, its application may be limited to cases where the application of coarser-resolution satellites is not feasible. We identified scenarios where PS may be more beneficial than Landsat-8 and Sentinel-2. These include measuring water quality parameters that vary daily, in small ponds and narrow coves of reservoirs, and at reservoir edges.

中文翻译：

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比较PlanetScope和Landsat-8和Sentinel-2，以感知农业流域水库中的水质

农业径流运输的沉积物和养分会不规律地恶化水质，这对地面监测构成了挑战。卫星提供时空尺度的数据，可用于水质监测。与较高分辨率的卫星相比，PlanetScope纳米卫星具有的空间（3 m）和时间（每日）分辨率可以帮助改善水质监测。这项工作将PlanetScope与Landsat-8和Sentinel-2在检测关键水质参数方面的能力进行了比较。每颗卫星的光谱带都针对叶绿素a进行了回归三年（2017-2020年）内俄克拉荷马州13个水库的水质，浊度和Secchi深度数据。我们为每颗卫星开发了重要的回归模型。Landsat-8和Sentinel-2解释了叶绿素a的更多变异可能比PlanetScope的光谱带多。PlanetScope和Sentinel-2解释了浊度和Secchi磁盘数据的变化量相对相似，而Landsat-8解释了这些参数的变化量较小。由于PlanetScope是商业卫星，因此其应用可能仅限于无法使用较高分辨率的卫星的情况。我们确定了PS可能比Landsat-8和Sentinel-2更有利的方案。这些措施包括测量每天在小池塘和狭窄水库海湾以及水库边缘变化的水质参数。