Sustainable Earth Review
Volume:1 Issue: 1, Feb 2021

Groundwater has a fundamental role and is a key factor in economic development and environmental protection in our country. In recent years, due to drought-induced rainfall, the extraction of groundwater has increased at a widespread level that could have environmental and geological hazards. Imamzadeh Jafar plain with an area of more than 60 km2 located in the northeast of Gachsaran city has a very good and prone position for agriculture. Abundant use and abandonment of the aquifer by more than 40 wells has led to the criticality of water resources and the loss of static levels, especially during the droughts in this plain. Boolean logic has been used to investigate the impact of watershed geological formations on the quantity and quality of wells. In this study, in order to investigate the spatial relationship between these wells and existing geological formations in the studied watershed, 4 buffers with distances of 1, 3, 5 and 10 km were created around each well. The results of these buffers showed that at 1, 3, and 5 km distances, Quaternary formations (Qft) with an area of 80.82, 47.13, and 35.19 percent had the greatest impact on the water quality of the wells, respectively, while at a distance of 10 km. The impact of the Fars Group formations, especially the Gachsaran Formation (Mgs), had the greatest impact on the water quality with an area of 26.92%.

Water access in Fiji is a critical issue as not everyone can access reticulated water sources which poses heavy dependence on groundwater sources. Along with its various uses, groundwater sources have been left vulnerable to contamination and depletion over the years due to changes in climatic patterns and human influence.  Traditional hydrometric groundwater survey is performed monthly to help determine recharge potential areas in Fiji but doesn’t cover all the water sources nor considers all the factors contributing to groundwater recharge. GIS, presents a contemporary approach to identify potential recharge areas which has been used in this study. In this study, the Multi Influencing Factor technique was used to determine the weightage of the factors aspect, slope, soil drainage, drainage density, parent materials and rainfall which are believed to have potentially contribute to groundwater recharge.  The basic GIS tools of overlaying and reclassification was used to denote the relationships between the factors and groundwater recharge and the potential groundwater recharges areas for Viti Levu and Vanua Levu.  Results have shown that higher potential areas are mostly areas with lower altitudes such as plains, wet areas (windward side), water bodies, excessively drained soils and parent materials with high exposure to weathering. Low ground water recharge potential areas are mostly mountainous, poorly drained soils, dense vegetation and poorly permeable bedrocks. These information is compared against existing boreholes and findings are to assist the government to invest more in those areas that have high recharge areas.

This study was conducted to determine the most suitable mulch regard to environmental adaptation. It was carried out as a completely randomized design with treatments including cement mulch (50 g cement +100 g sand +1000 ml H2O), two rates of polymer (5 and 10 g polyvinyl acetate + 1000 ml H2O), two rates clay mulches (100 and 200 g zeolite + 1000 ml H2O, 100 and 200 g bentonite + 1000 ml H2O), and control (1000ml H2O). After applying the treatments, trays containing moving sands together with different mulches air dried and the rate of soil erosion was measured during 20, 40 and 60 minutes by wind tunnel at a speed of 85 km h-1. In addition, the penetration resistance, the abrasion resistance, crust thickness, and the impact strength were measured. Data were analyzed using SPSS software. The results of this study showed that the applied treatments increased the penetration resistance, crust thickness, impact strength, and abrasion resistance and reduced the wind erosion; so that 10g of polymer mulch and 200 g bentonite have the highest resistance against wind erosion and are recommended as suitable treatments for stabilization the moving sands in arid lands such as studied area.

Widespread land use changes and unusual uses of highlands in Northern Tehran (Darakeh-Velenjak Watershed) have markedly caused to pose environmental risks and unsustainability. This research aims to study land use changes in Darakeh-Velenjak Watershed, to identify the key risks which can be posed by land use changes, and to present appropriate strategies using mitigation approach. To study land uses changes, satellite images were used (TM 1987, ETM+ 2000, and IRS 2018) and assessed by concentrating on four classes of land including vegetation, arid, roads and built-up areas. To extract the necessary information from the satellite images, Supervised Maximum Likelihood Classification algorithm was used, further complemented by visual interpretation methods. The sample population for conducting the Delphi technique consisted of 34 experts. The results of this research exhibited that from 1987 to 2018, vegetation had dramatically decreased, while arid, roads and built-up areas had increased. The results also revealed that in 1987, around 37.3% of the study area was covered with vegetation while in 2018, less than 14.54% of the area was covered with vegetation. In contrast, built-up, roads and arid areas which respectively covered 8.96%, 1.75%, and 51.99%, increased to 15.18%, 3.19% and 67.08% in 2018. In addition, the results of this study illustrated that key risks of land use changes in the Darakeh-Velenjak Watershed could be divided into natural and human risks. The human risks with an average score of 4.21 were more than natural risks. Finally, strategies have been presented using mitigation approach in the study area. Results revealed that avoidance strategies with an average score of 3.37 were situated in the first rank because unfortunately this watershed has been damaged by excessive land use changes in an aspect of developing buildings, roads, tourism infrastructures and etc.

River channels have been affected by climate changes and human interventions such as channelization, dam, gravel and sand mining and land use changes. Dam changes water and sediment transport in river systems. These changes are as one of the most important factors affecting upstream and downstream river morphology. The aim of this paper is to explain the effect of Taleghan dam (it was constructed from 2001-2006) on upstream of Taleghan River over the period 2000–2017. Taleghan River is very important river in the Central Alborz of Iran. For this reason, Taleghan River was divided 2 reaches as control reach and backwater reach. Channel morphology have been investigated using historical aerial photographs, remote sensing images and field observations. Also channel width, sinuosity index, and particle size distribution were calculated for two reaches pre and post-dam construction. Results showed that the channel width was increased in the post-dam period. Widening was dominated in the backwater and the control reaches but increasing in the channel width in the backwater reach is more than the control reach.  the channel width has been increased due to the impact of the dam and flood events. Also the results of grain size distributions showed that dam affects the grain size distribution and leads to an increase in the fine particle size. Finally, the channel adjustment (aggradation and widening) in upstream of Taleghan River may cause floodplain inundation and damage to agriculture and residential area in floodplain.

Today, cities in the world are facing a range of related economic, social and environmental issues and problems. The reason of axial study on the subject of urban regeneration policy by urban researchers and planners in the world is that this program will be unifying and integrating all economic, cultural, social, environmental and physical aspects in urban structure. Urban public spaces and civil society are the mirror of social power, intelligence and development of their people as much as they can make strong social cohesion, health and welfare of the citizens. These spaces bring about human activities' integrity, solidarity of spatial organization of city and social capital production. The main questions of this study are: What is the relationship between civil authority, consciousness and urban regeneration?  What factors influence on lack of public authority in the urban regeneration? The results of this study show that process of urban regeneration would be effective stimulus if the city has been built and operated basis on the human reason, consciousness and authority in public realms as civil society. In this case, the city can also be effective to restore and strengthen its neighborhoods. One of the main characteristics of Iranian urban spaces is existence of unfair approach which has caused to descend access of all people to the facilities and equipment of life and activity.