Monitoring spatiotemporal variations in nutrients in a large drinking water reservoir and their relationships with hydrological and meteorological conditions based on Landsat 8 imagery

Yuan Li; Yunlin Zhang; Kun Shi; Guangwei Zhu; Yongqiang Zhou; Yibo Zhang; Yulong Guo

doi:10.1016/j.scitotenv.2017.05.075

Monitoring spatiotemporal variations in nutrients in a large drinking water reservoir and their relationships with hydrological and meteorological conditions based on Landsat 8 imagery

Sci Total Environ. 2017 Dec 1:599-600:1705-1717. doi: 10.1016/j.scitotenv.2017.05.075. Epub 2017 May 19.

Authors

Yuan Li¹, Yunlin Zhang², Kun Shi³, Guangwei Zhu³, Yongqiang Zhou⁴, Yibo Zhang⁴, Yulong Guo⁵

Affiliations

¹ Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; School of Tourism and City Management, Zhejiang Gongshang University, Hangzhou 310018, China.
² Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China. Electronic address: ylzhang@niglas.ac.cn.
³ Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China.
⁴ Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China.
⁵ College of Resources and Environmental Sciences, Henan Agricultural University, Zhengzhou 450002, China.

PMID: 28535599
DOI: 10.1016/j.scitotenv.2017.05.075

Abstract

Nutrient enrichment is a major cause of water eutrophication, and variations in nutrient enrichment are influenced by environmental changes and anthropogenic activities. Accurately estimating nutrient concentrations and understanding their relationships with environmental factors are vital to develop nutrient management strategies to mitigate eutrophication. Landsat 8 Operational Land Imager (OLI) data is used to estimate nutrient concentrations and analyze their responses to hydrological and meteorological conditions. Two well-accepted empirical models are developed and validated to estimate the total nitrogen (TN) and total phosphorus (TP) concentrations (C_TN and C_TP) in the Xin'anjiang Reservoir using Landsat 8 OLI data from 2013 to 2016. Spatially, C_TN decreased from the transition zone to the riverine zone and the lacustrine zone. On the other hand, C_TP decreased from the riverine zone to the transition zone and the lacustrine zone. Temporally, C_TN displayed elevated values during the late fall and winter and had lower values during the summer and early fall, whereas C_TP was higher during the spring and lower during the winter. Among the environmental factors, the rainfall and the inflow rate have strong positive correlations with the nutrient concentrations. TN is more sensitive to meteorological factors (wind speed, temperature, sunshine duration), and the spatial driving forces vary among the different sections of the reservoir. However, TP is more easily influenced by human activities, such as fishery and agricultural activities. Current results would improve our understanding of the drivers of nutrients spatiotemporal variability and the approach in this study can be applicable to other similar reservoir to develop related strategies to mitigate eutrophication.

Keywords: Environmental factors; Eutrophication; Landsat 8 OLI; Nutrients; Xin'anjiang Reservoir.