Biodiversity & Biosafety
Mehdi Mehdinasab
Abstract
New methods of risk assessment can significantly reduce the severity of risks and consequently the environmental damage and move towards sustainable development. In this study, using the DPSIR model, the threats and environmental values of Poldokhtar wetlands in the ecological, hydrological and ...
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New methods of risk assessment can significantly reduce the severity of risks and consequently the environmental damage and move towards sustainable development. In this study, using the DPSIR model, the threats and environmental values of Poldokhtar wetlands in the ecological, hydrological and social areas were evaluated and based on the threat score, values and relationship between threats and values, the assessment of wetlands vulnerability and strategies Management was provided in response to the driving forces, pressures, situation and effects of risks. The results showed that ecologically, hydrologically and socially, droughts, fires, and wetland drainage resulted in reduced biodiversity, increased water turbidity and reduced water retention and functional reduction of hunting and hunting area of Poldokhtar wetlands. Effortless. The highest impact of ecological threats on wetland birds was 16.1 on average and the least impact on threats on arid plants with average 2 Environmental risks with a mean score of 10.3 would have an impact on water retention during the period of wetland dehydration, and a functional reduction of 8.6 percent wetland hunting and fishing area was the most important social risk impact.
Water Pollution
Mehdi Mehdinasab
Abstract
Water floods and floods in residential areas have always been one of the most common natural disasters in Iran after the earthquake that endanger human life. Between 2000 and 2008, approximately 99 million people are affected by floods worldwide each year. Kashkan River Basin with 8 sub-basins with an ...
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Water floods and floods in residential areas have always been one of the most common natural disasters in Iran after the earthquake that endanger human life. Between 2000 and 2008, approximately 99 million people are affected by floods worldwide each year. Kashkan River Basin with 8 sub-basins with an area of 9275.66 square kilometers, constitutes 22.4 percent of total Karkheh basin, with 290km length and 26 percent slope of the steepest and most flooded Karkheh basin. The results of statistical analysis on the instantaneous discharge data of Kashkan basin showed that from 1963 to 2019, 58 floods with average discharge moment of 1062.78 cubic meters occurred. In terms of time distribution, 65 percent of the floods in March, April and May and in terms of discharge rate 36 percent of the floods are more than 1000 cubic meters. The highest frequency of floods was observed in 1990-90 with 19 percent of floods and 14 percent of floods were severe, 22 percent moderate and 64 percent small flood. According to the Gamble distribution, a 200-year flood with a probability of 0.995 percent flood occurring at an instantaneous discharge of 4489.77 cubic meters with a tolerance of 535.06 cubic meters in the Kashkan Basin. As a result of the floods on 1 April, 14 people were killed and the damage was estimated to be 103.014 billion USD. The main causes of floods with an instantaneous discharge of 6,000 cubic meters per second in the Kashkan Basin can be attributed to precipitation with an average rainfall of 112.3 mm on 1 April and 321.5 mm for 9 days from 24 Mars to 1 April, respectively. Kashkan Basin, The occurrence of a flood with an instantaneous discharge of 3350 cubic meters on 5 March 2019, the absence of a significant reservoir dam for flood control, Impact of Babazid Bridge as a dam and runoff behind the bridge up to a radius of 5 kilometers and reaching the bridge ramp to the breaking point, thereby increasing the amount and velocity of the flood discharge to Poldokhtar, Decrease in river bed between 1 and 13 m in coastal wall reconstruction after flood on 4 February 2005 as a result of reduced capacity of Kashkan River in Poldokhtar during floods.
Environment Assessment
Mehdi Mehdinasab; Masood Bagherzadeh Karimi
Abstract
Environmental Impact Assessment is an important management tool that identifies natural and anthropogenic environmental hazards and their wide-ranging impacts and determines appropriate control calculations. Correct and accurate knowledge one of the threatening factors of wetlands Based on their importance ...
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Environmental Impact Assessment is an important management tool that identifies natural and anthropogenic environmental hazards and their wide-ranging impacts and determines appropriate control calculations. Correct and accurate knowledge one of the threatening factors of wetlands Based on their importance and impact can provide the basis for preventing and counteracting these factors more precisely, as well as preparing and implementing wetland conservation and environmental management plans. The vulnerability assessment method of Poldokhtar wetlands in this study is based on EFMEA failure states analysis method. for this purpose, first identify the most important environmental risks and threats in the hunting and hunting area of Poldokhtar wetlands in three categories of ecological, hydrological and social threats to 17 threats, then based on three variables: "probability, severity and extent of impact" Numerical values of each threat were determined and ranked according to the range of changes in five categories. The results showed that ecologically: wildfires and drainage in Gori Balmak and Piqué wetlands, hydrologically threatening to increase suspended sediment load, periodic droughts, and drilling deep and semi-deep wells in wetlands and social aquifers: low levels Environmental attitudes and knowledge of wetlands by the local community, lack of expert and wetland environments in the Department of Environment of the city and province are the most important threats in the 11 wetlands ecosystem of Poldokhtar. Overall, 88.2 percent of the risks were classified as risk-free, low- and medium-risk, and only 18.8 percent were high and infinite, requiring immediate action by wetland conservation and mitigation authorities.