Changes in Waste Water Disposal for Central European River Catchments and Its Nutrient Impacts on Surface Waters for the Period 1878–1939
2014
Gadegast, M. | Hirt, U. | Venohr, M.
Industrialization and urbanization in central Europe since the middle of the nineteenth century led to changes in urban waste water disposal and thus, to an increasing nutrient impact of surface waters by human waste. Based on historical statistics and literature research, we have made a quantification of nutrient loads discharged to surface waters in central European river catchments for seven decades between 1878 and 1939. For both total nitrogen (TN) and total phosphorus (TP), nutrient inputs via point (urban) and diffuse (rural) pathways, nutrient removal by waste water treatment plants (WWTPs) and that during soil passage were quantified. The total nutrient inputs caused by human waste between 1880 and 1940 increased from 243 to 396 kt TN year⁻¹, and from 18 to 30 kt TP year⁻¹. In 1880, most of the inputs (92 % for TN and 93 % for TP) originated from diffuse pathways (cesspits). In 1940, 43 % of TN and 41 % of TP inputs originated from urban pathways (sewer systems). The total nutrient removal between 1880 and 1940 declined from 79 to 59 % for TN and from 86 to 66 % for TP. Consequently, waste water disposal shifted from diffuse to urban pathways. On the one side, this led to rising nutrient loads discharged to surface waters because of insufficient nutrient removal by the early WWTPs. Otherwise, nutrient concentration in groundwater under rural areas decreased by discharge human waste via sewer systems out of the cities.
显示更多 [+] 显示较少 [-]