This article identifies and analyzes the effects of human pressures on the river systems, landscape, flow regime, and water quality in the Bucharest region, the largest urbanized area in Romania. The analyses focused on four streams crossing the Bucharest region, namely the Dâmboviţa, Colentina, Argeş, and Sabar rivers. Our approach relied especially on three types of information: (1) spatial data; (2) hydrological data sets; and (3) water quality data. We made a diachronic analysis of the available maps and ran classic statistical analysis of the data sets, as well as trend analysis. At the same time, we compared the flows in natural (reconstituted) and modified (current) regimes. The results showed that the stream system and its associated landscapes have considerably changed due to several engineering works (reservoirs, dams, channelization works, diversion canals, water intakes, etc.). Under these circumstances, the flow regime suffered changes that differed among the rivers. Thus, the multiannual discharges of the Argeş and Dâmboviţa rivers did not exhibit significant changes, but only mitigated the monthly discharge variability. In the case of Sabar and Colentina, a significant increase of the annual and monthly discharges was identified, due to the water transferred from the neighboring rivers. Water quality worsened, especially on the lower courses of the Dâmboviţa and Argeş rivers, degrading the states and health of the aquatic ecosystems in the study region.

The ecosystem services concept offers an interdisciplinary approach to the integrative study of both socio-economical and ecological systems. The sediment retention service is mentioned among the regulation ecosystem services in all the main international classifications (MA, TEEB, CICES). It refers to the capacity of ecosystems to regulate the quantity of eroded sediment reaching the stream network, and thus delivering benefits like maintaining soil and water quality and reservoir functions. This paper aims to assess the link between possible land cover changes and the sediment retention service provided by the vegetation cover. The analysis focuses on a mountain landscape from the upper catchment of Râul Târgului, Iezer Mountains in the Romanian Carpathians. To this purpose, we considered recent changes in the forest landscape (2005-2012) and, with the participation of local administrative stakeholders, we developed three land cover scenarios (Business-as-Usual, Conservation and Development). For each simulated land cover map we compared the supply of sediment retention services by using quantitative indicators: sediment retention, sediment export and the amount of potential soil loss. For the processing of spatial data we applied GIS techniques using the ArcGIS software (ESRI) and for the modeling we used the InVEST 3.2 software (Natural Capital Project). One of our major findings is that the landscape of 2012 retained approximately 3 million tons/year of sediment. Further on, our results show the highest decrease in the sediment retention service for the Development scenario and the highest increase for the Conservation scenario. However, these changes represent less than 2% of the 2012 values. Overall, our results show that the tools and models used proved to deliver credible and relevant results and can be used for future local landscape planning