Environmental diagnosis of an urban basin from a social-ecological perspective.

The critical factor in restoration and conservation of urban streams and their catchments is the human population, however the most of studies of urban ecosystems do not present social descriptors as concrete variables of analysis. The objective of this study is to perform an environmental diagnosis from a social-ecological perspective by considering both ecological and urban development descriptors of an urban basin. We selected 12 sampling sites of the Langueyú upper basin where social and ecological descriptors were determined.

Assessing the sensitivity of leeches as indicators of water quality.

The objective of this work was assessing the sensitivity of leeches to several water quality attributes in lowlands streams. We used occupancy modelling that account explicitly for detectability, to estimate the influence of four variables (dissolved oxygen, 5-days biochemicals oxygen demand, conductivity, and dissolved inorganic nitrogen) affecting nine species. We described the sensitivity as a change in the occupancy along the range of water quality attributes.