Figure 5
The weekly variations of [NH4 +-N] at the main stations of Yellow River and two tributaries during 2004 to 2015. The data was obtained from Data Center in Ministry of Environmental Protection of the People’s Republic of China (http://datacenter.mep.gov.cn/). The left y-axis indicates [NH4 +-N] and right y-axis indicates water discharge (Q). The x-axis indicates date from 1/1/2004 to 1/1 2016. The range of y-axis is same for all mainstream sites and x-axis is same for all sites. Map produced using ArcGIS software 9.3 (http://www.arcgis.com/features/index.html).
