جستجوی مقالات مرتبط با کلیدواژه "trophy" در نشریات گروه "شیلات"

Over the past years, eutrophication due to human activities has been recognized as a major ecological problem for the coastal areas, which in turn leads to significant changes in physicochemical and biological factors. The aim of the present study was to determine the eutrophication status of the Gorgan Bay, which was evaluated using the Carlson index as one of the efficient methods for assessing the eutrophication status of water bodies. The Gorgan Bay is located in the southeast of the Caspian Sea. The sampling was carried out in 23 stations with three replications seasonally from summer 2018 to spring 2019. Nitrate, phosphate, chlorophyll α, depth, and transparency were measured in each sample. Carlson's index in terms of chlorophyll α showed that the bay is in the eutrophic status in three seasons including summer, autumn, and winter (with the numbers 53.48, 53.69, and 53.67, respectively), and the mesotrophic status in spring (with the number 42.75). In terms of phosphate concentration, the bay was eutrophic in autumn and winter, and in summer (69.22 and 55.17) and oligotroph in spring (26.75 and 35.30), while in terms of transparency the bay was categorized as eutrophic in all seasons (63.33, 61.61, 69.93 and 61.58, respectively). In general, the results showed that the bay is in the range of mesotrophic to eutrophic status and therefore, more conservation management of this unique ecosystem is essential.

Determination of trophic status is one of the methods for assessing ecological balance of wetland ecosystems, because sustainability and productivity based on these unique ecosystems require proper monitoring and control of their environmental conditions. Therefore, biological and ecological studies are necessary before any activity is established. Tanudar Wetland with an area of 1000 hectares is one of the largest wetlands of Lorestan Province, 10 km northwest of Dorood. In this study, physical and chemical characteristics of Tondar wetland sampling were used to evaluate the nutritional status of Carlson (TSI) based on total phosphate (TP), total nitrogen (TN) and phosphorus to nitrogen (PN) Sampling of Tanudar wetland was used in summer of 2019. The results showed that based on the Carlson Trophic Index (TSI), trophic wetland Tanudar level is in eutrophic conditions. wetland Tanudar to its location, natural conditions and hydrological conditions, the is mainly drained from the highlands of Silakhor plain and tira River Dorood, Therefore, any upstream loading such as orchard development, diversified recreational harvests in the river, increased levels of dark river water pollution caused by municipal, industrial wastewater, and point source pollution sources such as warm-water fish ponds have crossed the Tanudar wetland. And it wound deeper on the current unstable body. Therefore, in the current conditions, the quantitative and qualitative provision of the wetland ecological right of the wetland is one of the most obvious requirements and management issues of the wetland.