33 research outputs found
Molecular genetics study on population of Salmo trutta caspius spring and autumn forms in Southern Caspian Sea using microsatellite marker method basin and establish an alive gene bank
Caspian brown trout (Salmo trutta caspius) is an important from the point of economy. In this study genetic diversity of (Salmo trutta caspius) was investigated using microsatellite markers from two regions of the Iranian coastline of Southern Caspian Sea (Cheshmeh Kileh River in Mazandaran Province and Karganrud River in Gilan Province). The purpose of this research was the study of Salmo trutta caspius possible populations related to genetic diversity and population structure in the Caspian Sea and introducing the useful genetic markers. For this purpose the number 225 fishes from two Rivers were collected. DNA was extracted and amplified with 16 pairs of microsatellite primers using Polymerase Chain Reaction (PCR). The amplified products were loaded on polyacrylamide gels and bands were analyzed using Gene Alex and Pop Gene soft wares. Observed and expected heterozygosity averages were 0.46 ± 0.09 and 0.60 ± 0.10, respectively. According to the results from this study, Genetic polymorphism has been seen in this population
Extent and Causes of Chesapeake Bay Warming
Coastal environments such as the Chesapeake Bay have long been impacted by eutrophication stressors resulting from human activities, and these impacts are now being compounded by global warming trends. However, there are few studies documenting long-term estuarine temperature change and the relative contributions of rivers, the atmosphere, and the ocean. In this study, Chesapeake Bay warming, since 1985, is quantified using a combination of cruise observations and model outputs, and the relative contributions to that warming are estimated via numerical sensitivity experiments with a watershedâestuarine modeling system. Throughout the Bayâs main stem, similar warming rates are found at the surface and bottom between the late 1980s and late 2010s (0.02 +/- 0.02C/year, mean +/- 1 standard error), with elevated summer rates (0.04 +/- 0.01C/year) and lower rates of winter warming (0.01 +/- 0.01C/year). Most (~85%) of this estuarine warming is driven by atmospheric effects. The secondary influence of ocean warming increases with proximity to the Bay mouth, where it accounts for more than half of summer warming in bottom waters. Sea level rise has slightly reduced summer warming, and the influence of riverine warming has been limited to the heads of tidal tributaries. Future rates of warming in Chesapeake Bay will depend not only on global atmospheric trends, but also on regional circulation patterns in mid-Atlantic waters, which are currently warming faster than the atmosphere.
Supporting model data available at: https://doi.org/10.25773/c774-a36