Songhua River, Manchurian Plains
Flowing lazily across the Manchurian Plain of northeast China, the Songhua River makes for an excellent case-study of a meandering river system. The various shades of brown in this photo highlight the system's bar and swale topography, a series of ridges and adjacent lows which form with progressive migration of point bars. Areas of piercing blue water are classic examples of ox-bow lakes, which form as a meander is cut off and abandoned by the main river channel.
This fluvial system is sourced from the astounding Changbai Mountains, and flows northward over 1,400 km to become the largest tributary of the Heilong River. Further downstream the Heilong River becomes known as the Amur River, as it breaches the Chinese border with Russia and continues to flow until reaching the Strait of Tartary.
With such wide reliance on its water supply, the Jilin chemical plant explosion of 2005 which released over 100 tonnes of toxins (dominantly benzene and nitrobenzene) into the Songhua River became both an environmental and political crisis. Notoriously poor management of the spillage by Chinese authorities led to chaos as the slick passed through Harbin, a city of nearly 10 million, and threats of lawsuits from Russian officials as the slick flowed down the Amur and into the Strait of Tartary.
The aftermath of the incident, however, has been somewhat positive. The long-term impact of the spill has been low, and the international attention the disaster received paved the way for several reforms in China's environmental protection policies. It also acted as an instigator for further accountability within the Chinese government, leading, apparently, to greater transparency.
-A.G.C.
Image: http://go.nasa.gov/1QVONvs Scale: 31.9 km x 41.0 km
Sources: http://bit.ly/1N0iENg http://bit.ly/1OkLlrz