Black and Odorous Water Monitoring by Using GF Series Remote Sensing Data

In China, due to the fast growing of urbanization and industrialization, many water-bodies have been affected to show strong evidence of Black and Odorous (BO) properties, which cause a huge impact on the people’s daily life and destroy the ecosystem around the water-bodes. Therefore, it is very important to monitor the BO condition in the urban area. In order to monitor the black and odorous water (BOW) and protect the environment in the urban area, the government has issued a regulation for urban black odorous water monitoring named as “Action Plan for Prevention and Control of Water Pollution” in 2015. However, there does not have an effective method to monitor the BOW from the macro level until the employment of remote sensing technology. The remote sensing technology uses the optical characteristics of the water body, and the spectral properties of the reflection and absorption of organic matter in the water to inverse the BO level. Due to faster progress of remote sensing technology, the monitoring of BO by using remotes sensing data become more and more accurate and efficient. The Chinese High-resolution Earth Observation System (CHEOS) is one the major project of China. It consists of five sub-system, the space-bornee observation system, near space observation system, aerial observation system, data management system and application system. For space-bornee observation system, it has seven series of observation satellites in a constellation which are named as GF1-GF7. GF1 and its counterpart satellites GF1B/C/D have optical payloads with 2m spatial resolution in Panchromatic mode (Pan) and is able to working together as sub-constellation to improve the time resolution of GF1. GF2 is a sub-meter optical observation satellite. GF3 is a C-band multi-mode Synthetic Aperture Radar (SAR) satellite. GF4 is a geostationary earth orbit optical satellite for the purpose of high time resolution imaging with the characteristics of 3 images per minutes. GF5 is a hyper-spectrum optical satellite with five other different payload for atmosphere and land monitoring. GF6 is specially designed for the application of smart agriculture with its four added spectral bands compared with GF1. GF7 is 3D sub-meter mapping satellite with three payloads. In order to demonstrate the inversion of BO level by using GF remote sensing data, the Luoshe town is selected with the characteristics of massive water body network and fast growing in urbanization. In this paper, the general payloads information of GF series satellites have been introduced. The demonstration of BOW inversion by using GF series remote sensing data in the area of Luoshe is performed over a period form 2019 to 2020. The results demonstrate a clear pattern of BO changing along with the changing of seasonal temperature and the water flow dynamic. In conclusion, the BOW monitoring method by using GF series remote sensing date is highly effective, specially in a large scale with a time frame can be achieved by weekly or daily with the fusion of multi-satellite data.