علوم زیستی دریا
matin khaleghi; Ahmad Savari; Alireza Safahieh; Mohsen Hamidian pour; Sadroddin Ghaemmaghami
Abstract
This study was carried out in the Gowatr mangrove forests in Gulf of Oman, on September 2017 and May 2018 during high tide with the aim of quantifying production, biomass carbon stocks of Avicennia marina and introduce of PnET-CN model. The results was showed that the mean of aboveground biomass was ...
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This study was carried out in the Gowatr mangrove forests in Gulf of Oman, on September 2017 and May 2018 during high tide with the aim of quantifying production, biomass carbon stocks of Avicennia marina and introduce of PnET-CN model. The results was showed that the mean of aboveground biomass was 28.09 ± 4.52 and 28.51 ± 4.49 t/ha, moreover, the mean of aboveground carbon stock was 11.22 ± 1.83 and 11.34 ± 1.7 t/ha, and the mean of primary production was 219.251 and 238.171 gC/m2.mo in September 2017 and May 2018, respectively. The estimated of the production and biomass carbon stocks using PnET-CN model was showed that the mean of production was 289.051 and 291.487 gC/m2.mo and the mean of aboveground biomass carbon was 12.29 and 12.76 t/ha in September 2017 and May 2018, respectively. The PnET-CN model could predict the effects of simultaneous changes in several environmental variables on the interactions among several ecosystem processes and it could estimate the amount of tree carbon stock and primary production with proper validation. PnET-CN model shown ecosystem models extended our understanding of the forest carbon cycle spatially and temporally and generated additional information about carbon stocks and fluxes.
علوم زیستی دریا
Sanaz Ahmadi Falehi; Ahmad Savari; Nasrin Sakhaei; Faedeh Amini; Babak Doustshenas
Abstract
Planktonic crustaceans are of specific importance in energy transfer due to their location in the middle links of the food chain of aquatic ecosystems. Therefore, they directly affect the abundance and diversity of the higher categories of the food pyramid, especially stocks and fishery resources. In ...
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Planktonic crustaceans are of specific importance in energy transfer due to their location in the middle links of the food chain of aquatic ecosystems. Therefore, they directly affect the abundance and diversity of the higher categories of the food pyramid, especially stocks and fishery resources. In this study, the impact of a tidal cycle on the zooplanktonic Crustacean ecosystem in the estuarine Bahmanshir River (Northwestern Persian Gulf) was studied. Our samples were collected during the spring of 2018 by plankton net with mesh sizes of 100 μm. Samples were taken at 5 stations to have a tidal effect on the abundance of zooplankton, approximately from 8:00 to 18:00 every two hours. In general, 72 species belonging to 28 families related to 3 groups of crustaceans named Cirripedia, Cladocera, and Copeoda were observed. The highest percentage of relative abundance was related to Cladocera with 35%, which was caused by the abundance of Daphnia mendotae. The highest diversity (Shannon index = 2.71 ± 0.04) of copepods was revealed to be caused by the large number of species at station 5 (near the mouth of the Bahmanshir River). Most species among the families belong to the Acartiidae family, which has 10 species of Acartia. The results of PCA analysis showed that among environmental factors, salinity has a direct effect on the total density, density of Harpacticoida and Calanoida, in the first component. The tides appear to significantly affect the density and types of planktonic crustaceans during the mentioned springtime periods. Our results showed relatively strong influence of the tidal cycle on the spatial pattern of Copepod assemblages in the study area. This study may be useful for future biological monitoring and seawater salinity intrusion into rivers in the northwest of the Persian Gulf.
علوم زیستی دریا
Kobra Jalali; Babak Doustshenas; Ahmad Savari; Nasrin Sakhaei
Abstract
The transfer of alien and invasive species through the ballast water of vessels is one of the most important threats to aquatic ecosystems. This study aimed to investigate the ballast water of 10 vessels entering the export port of Majidiyeh Mahshahr in 2018. A sampling of zooplankton from each ...
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The transfer of alien and invasive species through the ballast water of vessels is one of the most important threats to aquatic ecosystems. This study aimed to investigate the ballast water of 10 vessels entering the export port of Majidiyeh Mahshahr in 2018. A sampling of zooplankton from each vessel was performed by filtering 100 litres of ballast water of each vessel using a plankton sampling net with 50 μm mesh with three replications. Simultaneously, environmental factors including dissolved oxygen, acidity, temperature, and salinity were measured with 3 replications in the ballast water of the vessels. The results of a one-way analysis of variance showed that there is a significant difference between the vessels entering the export port of Majidiyeh in terms of the average density of Copepods. The highest average density 3.2×104 ind/m-3 and the number of species (36 species) related to ARGO1 ship from Bandar Abbas and the lowest average density 1×104 and the lowest number of species (24 species) belonged to PRECIGIOUS and GUNISHLI from Fujairah, UAE, respectively. There was a significant positive correlation between the average density of Copepods with temperature and dissolved oxygen. In total, 3 orders, 20 families, 28 genera, and 56 species were identified. All identified species except Oithona davisae have been previously reported from the Persian Gulf. O. davisae species was found only on the CONSTANTINOS ship from the port of Fujairah, UAE. It is native to the coastal waters of East Asia, especially around Japan and China, and has been reported in the Black Sea, the central Mediterranean, and more recently in the Aegean Sea. This research can be important for assessing the potential risk of new invasive species as well as for improving the quantitative and quality management practices of ships' ballast water.
علوم زیستی دریا
Nasrin Abdolkhanian; Heeva Elmizadeh; Ali Dadolahi Sohrab; Ahmad Savari; Mohammad FayazMohammadi
Abstract
Water resources under threat of pollution such as industrial waste, fertilizers, pesticides and urban sewage that negative effects on the environment and ecosystems. Arvand Rood is one of the most important navigable rivers in Iran, and it’s the most traffic place for floating which don’t ...
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Water resources under threat of pollution such as industrial waste, fertilizers, pesticides and urban sewage that negative effects on the environment and ecosystems. Arvand Rood is one of the most important navigable rivers in Iran, and it’s the most traffic place for floating which don’t have any system for delivery waste materials and discharging these waste materials in water making oil pollution. In this research, modeling pollution in the Arvand River using three-dimensional and hydrodynamic model to simulate how the pollution is studied, the Navier-Stokes equations in three dimensions and equations are solved transfer salinity and water temperature separation method. Boundary conditions applied, including changes in temperature, salinity and flow rate, temperature and salinity changes and apply for open border river and tidal components O1، S2، M2 and K1 open sea in the model used for the border. The results of modeling pollution in Arvand After running the model revealed that the pollution is pollution in the Arvand River according to location and time of release, In other words, in the Arvand River pollution from one point to another and from season to season is different, in fact, pollution is reciprocating mode. Diffusion of oil pollution in Arvand rood is depending to current. And in low tide because of same side of river current with low tide pollution reached to the Persion Gulf with high speed. The results shows, represent the effect of tie on diffusion pollution.