Analysis of bottom sediments in water reservoir Kolifiany from the aspect of Cd and Pb contents, the determination of observed heavy metal contents in different parts of carp body （meat muscle, liver and kidney） and...Analysis of bottom sediments in water reservoir Kolifiany from the aspect of Cd and Pb contents, the determination of observed heavy metal contents in different parts of carp body （meat muscle, liver and kidney） and the evaluation of hygienic status and suitability of fish meat for the human consumption were performed. For analysis, each tissue sample was dissolved in a solution of nitric acid p.a. （HNO3：HzO = 2：1）; sediment sample in solution of acids （HF-HNO3-HCIO4） and analyzed for presence of Cd, Pb by the atomic absorption spectrophotometer （AAS） Varian Duo 240FS and 240Z. Our results confirmed hygienic harmless of bottom sediments in water reservoir Kolifiany. The Cd, Pb contents in sediments represent no risk within their input into the fish organisms. The Cd content in fish meat is lower than maximum available amount given by legislative norms, and the contents of Pb in fish meat too. The results of Cd, Pb content determination in carp body confirmed that fish muscles belong to suitable foodstuff for the human consumption.展开更多
Fish introduction is one of the main causes of amphibian decline worldwide. It affects particularly rare aquatic phenotypes such as paedomorphs, which retain gills during the adult stage. In this context, we determine...Fish introduction is one of the main causes of amphibian decline worldwide. It affects particularly rare aquatic phenotypes such as paedomorphs, which retain gills during the adult stage. In this context, we determined whether small wetlands, such as pools surrounding fished and fishless lakes, could sustain paedomorphic and metamorphic newts. To this end, we surveyed lakes known historically to sustain Alpine newts Ichthyosaura alpestris as well as 35 nearby pools. On the basis of the published records, the only known population exhibiting paedomorphosis in the Swiss AIps was found to be extirpated by salmonid introductions. However, the metamorphs persisted in per- ipheral pools, paedomorphosis was discovered at a new locality, and overwintering larvae were still present in one of the lakes. These results show the importance of conserving varied aquatic habitats such as pools in mountainous environments where the main resources can become un- suitable for amphibians because of fish introductions. Pools may also function as reservoirs in maintaining newt populations until programs to remove fish from lakes can be carried out. It is not known if paedomorphs could reappear after fish removal. However, the combined resilience of am- phibians after fish removal and the genetic basis for paedomorphosis highlighted in other taxa by previous studies suggest that there is the potential to maintain this intraspecific case of diversity even after its disappearance.展开更多
文摘Analysis of bottom sediments in water reservoir Kolifiany from the aspect of Cd and Pb contents, the determination of observed heavy metal contents in different parts of carp body （meat muscle, liver and kidney） and the evaluation of hygienic status and suitability of fish meat for the human consumption were performed. For analysis, each tissue sample was dissolved in a solution of nitric acid p.a. （HNO3：HzO = 2：1）; sediment sample in solution of acids （HF-HNO3-HCIO4） and analyzed for presence of Cd, Pb by the atomic absorption spectrophotometer （AAS） Varian Duo 240FS and 240Z. Our results confirmed hygienic harmless of bottom sediments in water reservoir Kolifiany. The Cd, Pb contents in sediments represent no risk within their input into the fish organisms. The Cd content in fish meat is lower than maximum available amount given by legislative norms, and the contents of Pb in fish meat too. The results of Cd, Pb content determination in carp body confirmed that fish muscles belong to suitable foodstuff for the human consumption.
文摘Fish introduction is one of the main causes of amphibian decline worldwide. It affects particularly rare aquatic phenotypes such as paedomorphs, which retain gills during the adult stage. In this context, we determined whether small wetlands, such as pools surrounding fished and fishless lakes, could sustain paedomorphic and metamorphic newts. To this end, we surveyed lakes known historically to sustain Alpine newts Ichthyosaura alpestris as well as 35 nearby pools. On the basis of the published records, the only known population exhibiting paedomorphosis in the Swiss AIps was found to be extirpated by salmonid introductions. However, the metamorphs persisted in per- ipheral pools, paedomorphosis was discovered at a new locality, and overwintering larvae were still present in one of the lakes. These results show the importance of conserving varied aquatic habitats such as pools in mountainous environments where the main resources can become un- suitable for amphibians because of fish introductions. Pools may also function as reservoirs in maintaining newt populations until programs to remove fish from lakes can be carried out. It is not known if paedomorphs could reappear after fish removal. However, the combined resilience of am- phibians after fish removal and the genetic basis for paedomorphosis highlighted in other taxa by previous studies suggest that there is the potential to maintain this intraspecific case of diversity even after its disappearance.
