To assess potential causes for the decline in catch of brown trout and their impaired health status in Switzerland, a 5-year multidisciplinary research project was conducted. Multiple causal hypotheses were postulated and investigated in a variety of laboratory and field studies. We present here the application of a weight-of-evidence analysis to evaluate the results of these studies and to assess the causes for decline in brown trout abundance. Based on human health epidemiological criteria, the method considers the exposure situation, the correlation between causes and effects, specificity of effects, and amelioration due to removal. For our evaluation, we concentrated on four test rivers and included data on fish health and population density, water quality, and habitat parameters. Our results showed that proliferative kidney disease (PKD) caused by a parasite and clinical outbreak supported by other factors is a very probable single parameter for the decline of brown trout abundance at the sites of the test rivers where it occurs. Elevated levels of nitrogen compounds may also be posing a serious risk at several sites, in particular those downstream of sewage treatment plants. Several habitat parameters, such as large width, low percentage of riffles or elevated winter temperatures, were identified as factors likely contributing to impaired health, recruitment, and abundance at single sites. At most sites, more than one factor must be acting jointly to cause the observed decline in brown trout abundance.
from #AlexandrosSfakianakis via Alexandros G.Sfakianakis on Inoreader http://ift.tt/2hFHFHJ
via IFTTT
Εγγραφή σε:
Σχόλια ανάρτησης (Atom)
Δημοφιλείς αναρτήσεις
-
Treatment effectiveness holds considerable importance in the association between service quality and satisfaction in medical service studies...
-
from #AlexandrosSfakianakis via Alexandros G.Sfakianakis on Inoreader http://ift.tt/2p08wUI via IFTTT
-
Background. Transseptal puncture (TSP) can be challenging. We compared safety and efficacy of a modified TSP technique (“mosquito” technique...
-
FS Teni, AS Surur, A Hailemariam, A Aye, G Mitiku, AE Gurmu, B Tessema Annals of Medical and Health Sciences Research 2015 5(6):454-460 ...
-
Abstract Purpose Gastric cancer (GC) is one of the fatal malignancies worldwide with high occurrences but poor outcomes. bFGF has been s...
-
We provide excellent essay writing service 24/7. Enjoy proficient essay writing and custom writing services provided by professional academi...
-
Daily Mail Sarah was diagnosed with the cancer that killed Steve Jobs Daily Mail The symptoms Sarah Smith experienced on and off for...
-
Keratoconus (KC) is a corneal thinning disorder that leads to loss of visual acuity through ectasia, opacity, and irregular astigmatism. It ...
-
The Role of the Mammalian Prion Protein in the Control of Sleep. Pathogens. 2017 Nov 17;6(4): Authors: Roguski A, Gill AC Abstract ...
Δεν υπάρχουν σχόλια:
Δημοσίευση σχολίου