علوم زیستی دریا
Marzieh Afrakhte; Hossein Mohammad Asgari; Heiva Elmizade; Oliagholi khalilipour; Seyed Hossein Khazaei
Abstract
the important causes of drying up of wetlands in recent years in Iran are the continuation of drought, improper water management, land use change, and pressures caused by water shortage in the downstream areas of rivers. With the drying of the wetland, in addition to the reduction of local biological, ...
Read More
the important causes of drying up of wetlands in recent years in Iran are the continuation of drought, improper water management, land use change, and pressures caused by water shortage in the downstream areas of rivers. With the drying of the wetland, in addition to the reduction of local biological, social and economic services of the wetland, another big environmental problem is created, and that is the becoming wetland to dust source. This change causes many environmental, social and economic damages. The purpose of this research is to investigate the changes in the area of Horalazim wetland between 2000 and 2023. To achieve this goal, the Google Earth Engine {GEE} platform was used, and by using MODIS satellite images and calculating the NDWI index, the wetland area was calculated in each image. In order to check the condition of the wetland in detail, the annual minimum, maximum and average time series of the wetland area were extracted and the anomaly of area in three states of minimum, maximum and average were calculated. The results showed that the driest year is the year 2000 with less than 0.25 of the wetland area, and the largest area is in 2019 with about 3 times the average area. The analysis of the maximum and minimum limit series along with the corresponding images determines the areas affected by drought and flood, and it is possible to implement appropriate management programs in these areas during periods of drought and flood. It should be noted that by increasing the area of the wetland, the Horalazim dust center, which is one of the most active dust centers, is controlled.
علوم غیرزیستی دریا
Zahra Godini; Hossein Mohammad Asgari; Sorosh Zarghani
Abstract
Many wetlands and wet areas, including Hour al-Azim Wetland in Mesopotamia, is getting dried and small deserts have resulted that have been the source of many dust storms in recent years. One of ways to study this event is dust simulation and forecasting. In this study, the concentrations and behavior ...
Read More
Many wetlands and wet areas, including Hour al-Azim Wetland in Mesopotamia, is getting dried and small deserts have resulted that have been the source of many dust storms in recent years. One of ways to study this event is dust simulation and forecasting. In this study, the concentrations and behavior of dust in the wetland area of Hour al-Azim was investigated using WRF 3.7 numerical model and GOCART Schema. The corresponding model, taking into account the maximum parameters affecting the weather forecast that have a strong role in scale analysis, performs the corresponding calculations using the related equations and relations governing the atmosphere such as the equation of continuity, thermodynamic equations and observing atmospheric-chemical reactions, and produces the output as numeric matrices. The WRF model provides a reasonable estimate of the aerosols in the area under study in terms of scale and temporal changes. The concentration of PM10 simulated by the WRF model was compared with the hourly concentrations of the measuring station of the Khuzestan Department of Environment for Ahvaz. The simulated concentrations are in agreement with the hourly concentrations of the measuring station, which shows that the WRF numerical model is effective in simulating the concentration of particles. By examining the model It can be seen that the PM10 concentration in the simulation basin has been correctly obtained by the dust emission model in the study, so it can be said that the performance of the GOCART scheme in estimating the quantity of PM10 as dust concentration, especially in terms of the pattern of changes and the detection of storms, has an acceptable quality.
علوم زیستی دریا
Amir Bosak; Vahid Yavari; Hossein Mohammad Asgari
Abstract
One of the most important concerns in fisheries management is finding suitable areas and zones to invest in aquaculture with a sustainable development approach. The use of GIS is one of the most important factors for success in aquaculture development. Site selection of sturgeon breeding and farming ...
Read More
One of the most important concerns in fisheries management is finding suitable areas and zones to invest in aquaculture with a sustainable development approach. The use of GIS is one of the most important factors for success in aquaculture development. Site selection of sturgeon breeding and farming locations was carried out using the facilities of GIS and data analysis was performed using fuzzy model, hierarchical analysis process and the fuzzy criteria AHP. The main criteria used in this study were ecological, climatic, natural and environmental, economic and social factors, barriers and limitations and sensitive habitats. Then, using the weighting method, a competency map was prepared and with considering the merit and applying the average of the merit value of each place, the priority of each place was determined. Combining this method with fuzzy logic and application in GIS environment and also taking into consideration the weight and relative importance of each feature and option, has increased the efficiency of this method. According to the results, the highest weight was awarded to ecological factors (0.321), the next ranks were awarded to climate (0.205), economic and social (0.179), natural (0.167) factors and barriers and restrictions (0.129), respectively. The most suitable areas for the development of sturgeon breeding and culture centers are located in the northern, northeastern and eastern regions of the Khuzestan province. The most unsuitable sites are located in the southern regions of the province.
علوم زیستی دریا
Dariush Mohammadi kia; Ahmad Savari; Babk Dostshenas; Hossein Mohammad Asgari
Abstract
Plankton survey in coastal area of Southern Waters Qeshm was carried out in two season cold and warm and four stations (Parke Zeyton Beach, Soza Beach, Shibdraz Beach and Salakh Beach) during 2015 and 2016. In this study phytoplankton species belonging to 4 order Bacillariophyceae (Diatoms),Dinophyceae ...
Read More
Plankton survey in coastal area of Southern Waters Qeshm was carried out in two season cold and warm and four stations (Parke Zeyton Beach, Soza Beach, Shibdraz Beach and Salakh Beach) during 2015 and 2016. In this study phytoplankton species belonging to 4 order Bacillariophyceae (Diatoms),Dinophyceae (Dinofellagelates), Chlorophyceae and Cyanophceae (blue-green algae) were identified. phytoplankton identification was done until genus and 31 ditoms, 11 from dinofllagelates, 6 from Chlorophyceae and 4 genus from cyanophyceae were identified.The mean (± SE) of density, biodiversity indices of Simpson,Pielo Shannon and Margalef were respectively 6705.72±63.9 Cell/L, 0.82±0.34,1.12±0.17 , 1.9±0.19, and 2.61±0.38 in season warm and 5666.13±53.2 Cell/L, 0.77±0.06, 1.12±0.11 , 1.9±0.17 and 2.26±0.43 in season cold.The seasonal similarity based on Sorensen's and Jaccard's coefficients were highest (0.97 and 0.88) for - two season warm and cold. In addition, there were significant correlation between Simpson and Shannon-Weiner diversity with salinity and PO4, and phytoplankton density with salinity and pH. A ccording to the results obtained can be concluded that both the area of ecological conditions in ranks are instead moderate. Also, phytoplankton of diversity and richness is good.
علوم زیستی دریا
Seyyed Kiarash Jafari; Ahmad Savari; Faedeh Amini; Hosseim Mohammad Asgari
Abstract
The international Shadegan wetland is one the biggest ponds in Iran and located in Khouzestan province.This wetland is with more than 530 thousand hectares vast wetland registered in the international Ramsar Convention.Climate changes can make negative or passitive conditions by drought or wet periods ...
Read More
The international Shadegan wetland is one the biggest ponds in Iran and located in Khouzestan province.This wetland is with more than 530 thousand hectares vast wetland registered in the international Ramsar Convention.Climate changes can make negative or passitive conditions by drought or wet periods on water quality and volume of this wetland.Today, concerns about the warming of the earth and damage to vital natural resources, have led researchers to study different periods of drought. Drought is a phenomenon adverse impact on all ecosystems, including wetlands. Because of it, new drought indices should be associated with specific time scales for monitoring and management of water resources. In the study area, data required by the Metrological Agency, water and power authority and by ocean-atmospheric data from NOAA satellites from 1950 to 2015 (65 years old) received. Changes in wetland on the downside and upside of drought and wet were studied by standardized precipitation evapotranspiration index (SPEI). The final model showed decaying and destroying the wetland each year goes by drought from year of 1998.