Abutaleb Sabr; Mazaher Moeinaddini; Hossein Azarnivand
Volume 16, Issue 3 , October 2018, , Pages 79-100
Introduction: In recent decades, air quality change and its risks are correlated with the expansion of urban and industrial areas and other land-use changes. One of the important effects of land use/cover changes (LUCC) is wind erosion and as a result, an increase in particulate matter (PM) concentration ...
Introduction: In recent decades, air quality change and its risks are correlated with the expansion of urban and industrial areas and other land-use changes. One of the important effects of land use/cover changes (LUCC) is wind erosion and as a result, an increase in particulate matter (PM) concentration in residential areas. For this reason, the effects of LUCC on PM concentration in Tehran’s airshed was studied. Material and methods: Data on LUCC and landscape metrics were studied in the years 1985, 2000 and 2014. Then, the relationship between LUCC and PM concentration in Tehran was investigated by trend analysis methods. To find the most important wind directions with strong effects on Tehran’s air quality, conditional probability function (CPF) and directional relative strength (DRS) were used. Results and discussion: LUCC results showed that the area of agricultural land-use has been expanded from 1985 to 2000, yet decreased from 2000 to 2014. The trend was vice versa for barren lands during the mentioned time periods. In addition, the urban area has increased in the whole period. The landscape metric results showed that landscape patches became smaller and the landscape has been fragmented. The results of the PM10 concentration trend analysis revealed that it has been increased dramatically since 2007. Comparison of the average concentration of PM10 before and after 2007 showed a significant difference. The results of CPF and DRS illustrated that no specific wind direction was detected before 2007, but afterwards both increased in specific directions (south to west), which is compatible with most LUCC and fragmented areas in these directions. Conclusion: Our results showed that specific wind directions may lead to an increase in the PM10 concentration which is compatible with LUCC directions. Therefore, LUCC could be a significant reason for the increase in PM10 concentration in Tehran.
Naser Moghadasi; Sharareh Pourebrahim; Hosein Azarnivand
Volume 15, Issue 3 , October 2017, , Pages 203-220
The comprehensive identification of hazard risks in order to protect against them is one of the main steps in environmental management. Given the importance of environmental impact assessment in sustainable development, the development of a comprehensive system consisting of effective ...
The comprehensive identification of hazard risks in order to protect against them is one of the main steps in environmental management. Given the importance of environmental impact assessment in sustainable development, the development of a comprehensive system consisting of effective indicators is vital for the creation or exacerbation of environmental risks, on the one hand, and their monitoring, on the other. This comprehensive system can provide categorized information for different levels of decision-making and management. This study aims to assess the vulnerability to zoning of environmental risks by applying an ecosystem services approach. It also aims to integrate the ecosystem services concept into environmental risk assessment.
Materials and methods:
Initially, a complete list of environmental risks was prepared by desk study, using provincial and national documents and field studies, along with meetings with different institutions. This list consists of all potential or active factors that can lead to risks. The prepared list of risks was reviewed by experts in order to have their feedbacks and to finalize it. In this study, different risks, including an imbalance in provincial development, the likelihood of water erosion and fire, land use change, and incomplete protection of biodiversity were analyzed. AHP multi criteria decision making was applied for zoning the imbalance of industry with ecological suitability. RUSLE was applied for soil erosion and MAXENT for fire and incomplete protection of wildlife. To study land use/cover changes, cellular automata and the genetic algorithm were integrated.
Results and discussion:
The results of setting priorities using the multi criteria decision making technique revealed that some risks, including imbalance of industry on land, erosion, vegetation and land use changes, fire and incomplete protection of wildlife are the major risks to be considered. Results show that quality of the ecological area of Alborz Province has significantly reduced in recent years due to human factors such as the establishment of factories, creation of various industrial zones, soil erosion and degradation, drought, depletion of water tables, loss of accessible water resources, improper cropping patterns, population growth due to immigration from other provinces and climate change. The results of vulnerability assessment show that a massive pressure was exerted on sustainable use of the environment of Alborz Province by human impacts. Alborz Province suffers from various risks for which applying environmental services, such as conservation of soil nutrients, biodiversity and diverse vegetation of land, can be effective in their reduction.
Environmental risks are major threats to the degradation of resources and environmental services in Alborz Province which should be controlled and prevented. Complete identification of pre-existing risks and their spatial analysis can help in the development of conservation strategies for vulnerable areas.