Batch experiments were conducted to test the effects of various solution properties, such as pH, temperature, initial concentration and anoxic and aerobic atmosphere, on Cd removal by nanoscale zerovalent iron (nZVI) supported on industrial coal fly ash. Cd (II) could be removed by adsorption on fly ash-nZVI in a very short time (5 min) with high removal rates (greater than 99.9%) over a wide range of concentration (5–100 mg l ⁻¹ ). Cd (II) was physically adsorbed on the surface of fly ash-nZVI. The preparation of fly ash-nZVI can incorporate the use of waste media, making the overall adsorbent more removal efficient and low cost.

Trends in annual precipitation and river discharge (1956–2012) were analyzed using the Mann–Kendall test and Sen's method to evaluate the impact of climate variation and human activities on the Haihe River discharge to Bohai Bay. Compared to observations before 1965, two obvious decreases in annual river discharge occurred after 1965 and after 1980. Considering 1956–1965 as the baseline period, it was established that the reduction in Haihe River discharge to the Bohai Sea was 52.9% and 81.9% during 1966–1980 and 1981–2012, respectively. Compared to the baseline period, the reductions in annual precipitation in 1966–1980 and 1981–2012 were 7.1% and 14.2%, respectively. Following the increase in population, industrial activity, and irrigated areas, water consumption has increased rapidly, from 51.9 mm in 1965 to 124.8 mm in 1980 and 126.4 mm in 2000. These results indicate that the reduction in discharge in the Haihe River basin during 1966–1980 and 1981–2000 could be attributed to climatic variations (33.2% and 41.4%, respectively) and human activities (66.8% and 58.6%, respectively). The results also indicate that salinity in Bohai Bay increased following the decrease in discharge from the Haihe River.