Search results for "Water body"

Uncertainty estimation of a complex water quality model: GLUE vs Bayesian approach applied with Box – Cox transformation

2010

In urban drainage modelling, uncertainty analysis is of undoubted necessity; however, several methodological aspects need to be clarified and deserve to be investigated in the future, especially in water quality modelling. The use of the Bayesian approach to uncertainty analysis has been stimulated by its rigorous theoretical framework and by the possibility of evaluating the impact of new knowledge on the modelling estimates. Nevertheless, the Bayesian approach relies on some restrictive hypotheses that are not present in less formal methods like GLUE. One crucial point in the application of Bayesian methods is the formulation of a likelihood function that is conditioned by the hypotheses …

Uncertainty propagation throughout an integrated water-quality model

2010

In integrated urban drainage water quality models, due to the fact that integrated approaches are basically a cascade of sub-models (simulating sewer system, wastewater treatment plant and receiving water body), uncertainty produced in one sub-model propagates to the following ones depending on the model structure, the estimation of parameters and the availability and uncertainty of measurements in the different parts of the system. Uncertainty basically propagates throughout a chain of models in which simulation output from upstream models is transferred to the downstream ones as input. The overall uncertainty can differ from the simple sum of uncertainties generated in each sub-model, dep…

Diffuse and concentrated pollution control at watershed-scale: an Italian case study

2008

Point and non-point pollution assessment for a receiving water body quality management

2008

Migrations of hatchling European pond turtles (Emys orbicularis) after nest emergence

2013

Distances between nest sites of Emys orbicularis and the nearest water bodies can be long. We studied whether a longer distance could affect the probability of hatchling survival, migration time, and body mass loss. In our research area (Lubuskie district, western Poland), nest sites were situated on a slope; the closest water body was in a distance of 72-290 m. Near the water body we constructed a 550 m long drift fence to recapture hatchlings migrating down the slope. We monitored 32 hatchlings from 7 different nests deposited in the years 2008-2010. The hatchlings started to emerge from their nests on 9 and 13 April 2009, 7 and 9 April 2010, 30 March, 7 and 8 April 2011. Then, hatchlings…

Spatial and temporal variability of diatom and macroinvertebrate communities: How representative are ecological classifications within a river system?

2012

Evaluation of river condition is complicated by dynamic relationships between river assemblages and their environment. We assessed variation of ecological status classifications of stream diatom and macroinvertebrate communities within a boreal river system. We specifically examined whether results of ecological classifications are concordant across taxonomic groups and among main channel and headwater side tributaries of this river system. We further assessed whether ecological classifications are stable from year to year and whether classifications show predictable relationships to major stressor gradients. The estimated ecological condition varied considerably among and between reaches o…