نشریه علوم و تکنولوژی محیط زیست
سال بیست و سوم شماره 11 (پیاپی 114، بهمن 1400)

Distribution of heavy metals in rock units and their pollutants are necessary environmental issues which have high importance.

Because of not performed environmental geochemical studies of heavy metals in Iran based on chemostratigraphic studies, for this purpose, this study on chemofacies of Gachsaran formation in Kermanshah with the aim of assessing environmental heavy metal pollution was carried out. For determine the concentrations of heavy metals, XRF and ICP mass techniques were used and the amount of metal contamination was investigated using statistical softwares and pollution indices.

The results indicated high concentration of cadmium in sediments of Gachsaran Formation (3.3) ppm which is higher than (0.3) ppm in crust. All three used indices (Igeo, EF ANF CF) showed cadmium contamination in studied sediments but molybdenum, aluminum, cobalt and iron did not showpollution in sediments. Furthermore the values of CF and EF indices showed a similar trend about element contamination in sediments.

Significant amounts of cadmium in the Gachsaran Formation can be further affected by the dissolution process of rocks and sediments by surface and groundwater, as well as by biological (agricultural and mining) activities and can has non optimal environmental impacts. Therefore, it is necessary to anticipate and make the necessary arrangements in this case. High levels of cadmium in the sequences of the Gachsaran Formation can effected by dissolution, as well as biological activities (agriculture and mining).

Assessment of the resilience threshold based on the characteristics of landscape causes an appropriate management for vulnerability and identifying resilience areas. This study assessed the resilience threshold with the landscape ecology approach by using quantitative methods in the Gheshlagh river valley.

The study area was classified into five homogeneous zones based on the characteristics of the composition and distribution of the landscape structure, and the vulnerability and resilience of the zones were determined. The vulnerability was calculated based on the status of the signs and their changes, and the resilience of the zones was determined based on 5 resilience criteria including ability of resilience, speed of resilience, maximum resilience, amount of resilience, and possibility of resilience. The method of recording the quantitative characteristics of the landscape was completed using moving windows in the fragstat environment during the two periods of 2000 and 2018.

The results of the vulnerability assessment of the zones showed that the vulnerability of the zones were 33%, 25%, 23% and 20% for A, D, C and B, respectively. The results of the resilience of zones showed that the zones A and D are not resilience against the changes, and also the amount of resilience B is more than all zones, the speed of resilience C is also more than the other zones.

The characteristics of the composition and distribution of the landscape structure have significant effects on the environment and the resilience threshold with the landscape ecology approach is a suitable tool for assessing and monitoring of urban land use.

Given the rapid expansion of urban society and increasing energy consumption in developing countries, it is necessary to examine the relationship between urbanization and energy consumption. The purpose of this study is to investigate the relationship between urbanization and the consumption of renewable and non-renewable energy in selected developing countries.

In this research, the effect of urbanization rate on renewable and non-renewable energy consumption will be investigated using the Generalized Method of Moments (GMM) method and using two models. This study was conducted for 44 countries for the period 1996-2018. Estimation of the models has been done with Stata software. The research model was adopted from the linear Salim model.

According to the results of this study, every 10% increase in urbanization rate leads to a 1% increase in renewable energy consumption in developing countries. While every 10 percent increase in urbanization rates will increase the consumption of non-renewable energy in these countries by 4.2 percent. Therefore, in developing countries, the impact of urbanization rates on non-renewable energy consumption is greater than renewable energy.

The reason for more renewable energy consumption in developing countries is the greater dependence of heating and public and private transportation in developing countries on non-renewable energy, which must be changed gradually. This also indicates the low awareness and knowledge of the population about consumption patterns and also the low level of technology in these countries.

The middle space is at the same time a part of the public and private realm, which is defined by these two and defines them. The middle arena in residential complexes has a hierarchy of social relations, privacy and different territories. Nowadays, due to the destruction of the structure of historic residential architecture, the position of the middle arena has also suffered from deficiencies. The effect of physical and behavioral criteria in the middle spaces of residential complexes in Tehran on the degree of residents' attachment to the complex.

In the research, first; Data collection has been studied by recording events and fieldwork techniques in three residential complexes in Tehran. Through questionnaire and data analysis, correlation is analyzed through SPSS22 statistical software and significant relationships are inferred between the variables involved in the degree of attachment.

indicate that physical criterion components such as green space coverage, proportions, distribution, hierarchy and performance criteria with various components and behavioral adaptability in the middle spaces of residential complexes, respectively, have the greatest impact on residents' sense of attachment.

Results of the effect of the physical and functional components of the middle spaces cause those different areas of behavior are formed to meet a wide range of needs of residents, including the desire for social interaction, privacy and a sense of satisfaction as a result Develop their attachment to the residential complex.

One of the most important challenges regarding recent urban developments is the issue of urban facades, which has become more and more important due to the lack of harmony and coordination of urban facades with the natural context of cities. The main issue of the present study is the study and analyzing of the effects of urban views of recent constructions on the natural landscape and the visual effects of the urban landscape.

The methodology of the present study is applied in terms of purpose and descriptive-analytical in terms of method. And the research area is Namaz Boulevard located in the southern heights of Mashhad metropolis. First, in order to identify the visual qualities of the study area, field sampling method and photography tools were used, Then, the data were analyzed using graphic software and finally, using the VIA visual impact assessment method, the effects of urban facades on the natural landscape of the area were evaluated.

Findings show that the components of the relationship in the urban landscape of recent constructions have positive and direct effects and in some areas of influence due to lack of coordination and non-observance of rhythm and visual continuity and other adjacent criteria, direct, negative and medium-term effects. It has been left and in terms of components such as harmony and unity in architectural style, the type of materials and color palette used in urban facades, long-term negative effects are predicted for it.

The results of the present study indicate that in recent years, the elevation in Namaz Boulevard on the one hand and the inconsistency of construction patterns and architectural style with the urban context, have negative, direct and long-term effects on the natural landscape and lead to obstruction of vision and disturbances. Visual and loss of landscape and ecological structures are limited.

Increasing world population and need to more production, limited water resources and the indiscriminate use of them specially in arid and semi-arid regions and also the huge amount of sullage produced in cities and the necessity for proper disposal of them, increased the urgency (necessity) of using wastes in order to farming & feeding the under- ground aquifers. Cadmium, lead and nickel are such pollutants which can enter to water, soil and plant and finally to human and animals’ food chain from different resources.

This Study was performed to evaluate the amount of soil contamination in the south Tehran farms and mapping the studied area using geostatistical methods. From the 2000 hectares of the agricultural farms around Firooz Abad stream in Tehran south in 2014, 175 soil samples were selected with 300 meters intervals. Two methods of mapping including kriging and Inverse distance weighting (IDW) were used.

Based on mean concentration, the metals in studied area were in following decreasing order: nickel> lead> cadmium. According to the standards proposed by the environmental protection Agency of Iran, 13 and 9 % of soil samples are contaminated to total lead and nickel, respectively.

Due to the importance of point spatial variation of soil pollutants, the IDW method was identified as the suitable method for mapping the concentration of total lead and nickel. The total lead and nickel concentration in about 161 and 14 hectares of the agricultural lands, respectively, were more than allowed limits.

One of the most important international instruments to deal with climate change is the Paris Agreement 2015. For over three decades, states have begun long-term talks and negotiations on climate change, which is always on the international agenda. One reason for not concluding an international instrument is that states are not willing to adopt binding commitments on mitigating Green House Gas emission. The failed experience of the Kyoto Protocol 1997 reflects this approach. The piece analyzes the nature of states obligations in the Paris agreement on climate change. This research is based on a legal inductive analysis method. According to this method, the Paris Agreement and some related legal instruments on climate change have been analyzed and assessed. This article while identifies various defining elements of legal character of the Paris Agreement, illustrates that even though the Paris Agreement is an “International Treaty within the meaning of the Vienna Convention on the Law of Treaties” which contains a mix of hard, soft and non-obligations is an important step forward to address climate change, but still has legal and normative inefficiencies.

The accounting information system can play a significant role in helping to protect the environment. However, despite the important role of environmental accounting, no comprehensive index has been provided so far. Therefore, the main purpose of this research is to present a model to identify and rank environmental accounting indicators using ORESTE technique and based on grounded theory approach.

The present research is of applied and exploratory type. The present research has been conducted using a mixed research method in the two qualitative and quantitative parts. The statistical population of the research in the qualitative part is the faculty members of universities and in the quantitative part is 194 managers, experts and informed people in the field of environmental accounting.

In order to achieve the research objectives, the desired questions for the interview have been designed and finally the 6 factors of senior management commitment, uncertainty, strategy, social legitimacy, environmental monitoring and control, and accounting information system, and sub-components related to each factor based on grounded theory approach have been identified as the main factors in environmental accounting. Then, the identified indicators are placed in the form of a paired comparisons questionnaire and have been ranked using the ORESTE technique. The research results showed that the sub-indicators of senior management commitment factor including organizational justice, corporate social responsibility and ethical charter have respectively the highest ranks among the indicators.

According to the stated results, environmental accounting will be considered in manufacturing companies when organizational justice is perceived by companies and regarded by the government.

Population growth and unplanned urban development has led to increase the risk of disaster in urban areas. Achievement to knowledge and ways to deal with disasters, have attracted attention of residents and researchers to natural disaster management. The number and variety of published scientific papers in the field of natural disasters is one of the reliable proofs for showing the trend of researchers to this field. The objective of this research is meta-analyzing the published papers in Persian scientific journals.

 For meta-analyzing of theoretical approach of Natural Disaster Management in Iran, initially 29 journals are selected. Then 454 papers are selected among these journals. These papers have been published from 2002 to 2016. Finally, for analyzing the papers, the analyzing criteria such as research methodology, sampling method and planning model and approach are determined using the expert’s opinion.

The map of studies distribution showed that Tehran, Khorasan-e-Razavi, and Azerbaijan-e-sharghi provinces have been considered in a lot of papers. Results showed that physical approach is the dominant approach in the studies which is a weakness in papers. Also disregarding the scientific principle of research methodology such as absence of sampling, reliability, and validity is the other weakness of studies.

Considering the dominant approach in the previous studies, studying and using the community-based and organizational approaches in the future researches is proposed. The policies of scientific journals in publishing applied papers is led to aggregation of these papers in the journals. So it is proposed due to importance of theoretical and fundamental studies and identifying indicators in the field of disaster management, scientific journals would have special attention to theoretical papers in this context and providing the condition to presentation of more theoretical and fundamental papers in this subject.

The presence of dust in the sky of Iran causes dust deposition on the surface of photovoltaic panels and greatly affects the efficiency of them. The purpose of this study is to investigate the effect of dust, sand and temperature on the efficiency of photovoltaic panels.

Two similar panels were placed outdoors for 1 days to investigate the impact of dust. One of the panels is equipped with a cleaning system, but the other panel is without a cleaner. In the temperature setting, the control panel was equipped with a cooling system but the experimental panel was set without a cooling system. For investigation the effect of dust and sand, four similar panels were used, the control panel was in the clean condition, but the experimental panels were covered with dust and sand.

The results of this study indicate that dust deposition on the panel surface after 13 hour caused a decrease of 4% in voltage, 21% in current, 24% in power and an  increase of 4% in the temperature of the contaminated panel compared to the clean panel. The panel with the higher temperature has a reduction of 3% in voltage, 25% in current and 29% in power in comparison with the lower temperature panel. In addition, the voltage and current of the sandblasted panel decreased more than the voltage and current of the panel contaminated with dust.

According to the results of this study, dust deposition on the panel surface and increasing the panel temperature decrease the photovoltaic panel efficiency. Dust also has more impact on the photovoltaic panel than sand.