Environmental Sciences
Year:2009 | Volume:6 | Issue:3|Papers Count:23

Land application of municipal effluent is potentially beneficial as an inexpensive nutrient source. To investigate the effect of seven years of irrigation with Southern Tehran municipal effluent treatment plant effluent on the physical and chemical properties of soil and accumulation of nutrient in olive trees, a study was carried out using a random-systematic pattern with three replications. Treatments included: 1) municipal effluent and 2) well water (control). To investigate soil physical and chemical properties, accumulation of nutrient and Cd in leaves and fruits, samples of soil (0-15, 15-30 and 30- 60 cm), leaves and fruits were taken from each plot in three replications. Samples were analyzed with standard methods. In order to normalize the data, an independent sample t-test was used. Results of this study indicate that application of municipal effluents increase the concentration of Mg, N, P, K, Ca and Cd in different layers of soil (0-15, 15-30 and 30-60 cm depths) and Olea europaea , s leaves and fruits. Irrigation with municipal effluent increased olive fruit yield and leave weight.

Forest Ecosystem in addition to timber production has many social and environmental benefits. One of the most important benefits from the forest ecosystem is their role in air pollutants absorption and reducing the pollution level. In this study the economic value of SO2 absorption by forest has been estimated in a part of Caspian forest. At the first, the amount of absorbed SO2 has been calculated by existing models, separately for forest and rangeland that are two main land uses in the region. Then this function has been valuated with replacement cost method. The results show a value of 2475 thousand Rials for absorption of each ton of SO2. According to the area of region that is 20582 hectare, the total amount of SO2 absorption is 42.723 ton per year and its value is 106 million Rials per year for the ecosystem function of SO2 absorption.

Organic farming and organic production methods have gained importance in agriculture from environmental point of view as well as economical and social stand points. The purpose of this study was to propose a model in order to estimate the wheat production in organic farms of Khorasan province, Iran. Production of organic wheat was obtained through surveys of 167 farms. Partial elasticity of production of different inputs were derived from Cobb-Douglass production function. The results revealed that the wheat production decreased by 18.95 percent when the chemical factors were eliminated. The drop off yield of organic fields in large farms (more than 10 ha) is higher than small (less than 5 ha) and medium (5 to 10 ha) size farms due to over-use of chemicals and fertilizers. If organic products are to develop, it is recommended that financial support (subsidy), extension education, and providing non-chemical inputs be provided to compensate the related production loss.

Plants are one of the most important factors of rangeland ecosystems that have in close relation with other ecosystem factors. For the protection, restoration and stable development of these ecosystems it is necessary to recognize present relationships more and more. So, in this research some characteristics of Seidlitzia rosmarinus were studied. First, Seidlitzia rosmarinus plant types were identified in a cover map area of Yazd Province and the results of other research about this species were reviewed and collated. Results show that Seidlitzia rosmarinus is dominant in about 600000 hectares of lands located in the margin of Yazd playa. There are 10 plant types with Seidlitzia rosmarinus predominating and, out of 9 plant types, it is second or third species. The mentioned plant types are located at altitudes between 900- 1750 meters and where the average annual rainfall is lower than 100 mm. High water tables and salinity are two characteristics of this land. The flowering stage starts in early autumn and seeds ripen at the end autumn. High seed production and germination rate are useful characteristics for reproduction. This plant was consumed well by camels, so that not only in range grazing but also in hand feeding it has a suitable preference value. In order to control wilting of Seidlitzia rosmarinus, camel grazing was recommended. Furthermore, its forage can be harvest every other year and mixed with other forage for camel feeding. Sodium carbonate salt was extracted by biomass burning.

In this study, 105 specimens of Shemaya C. chalcoides were collected from the Haraz, Shirud and Gazafrud rivers in May 2004. Genetic variation and probable population differentiation were investigated using RFLP (Restriction Fragment Length Polymorphism) analysis of one PCR amplified genome segments (18S rRNA). The DNA was extracted from fish fins using the Phenol-Chloroform method. Five out of eight restriction enzymes (BamHI, EcoRI, RsaI, TaqI PstI, SacI, SacII, SmaI) showed polymorphism, and ten different haplotypes were detected. The estimated nucleotide sequence divergence ranged from 0.044568 to 0.049442 and the mean value of sequence divergence among populations was 0.045981±0.0000338. Monte Carlo simulation analysis with 1000 iteration showed that there were no significant differences among haplotypes in three populations. It seems that the three populations were homogeneous (c2=12.12, p³0.05).

Some biological traits of Killifish (Aphanius sophiae) of Cheshme Ali Damghan such as age and growth frequencies, condition factor, von Bertalanfy growth parameter, Gonadosomatic index, fecundity and egg diameter were studied monthly from October 2004 to November 2005. During the study 535 specimens were sampled with a net which bears a mesh size of 1mm. Sex ratio of Cheshme Ali population was 1 ♂ : 1.367 ♀ .There was significant difference between male and female (χ2=12.877, p=0.000)). Length and age frequency studies showed that female fishes were longer and older than male fishes. Male fishes had higher condition factor than females (F=40.037, p=0.000). Reproduction cycles of these fishes were estimated to be about 6 month and the peak of GonadoSomatic Index of females was in May. Eggs diameters were from 0.53 to 2.73 mm.

Diazinon is a chemical pesticide used for a wide range of agricultural and horticultural crops. However, its residue in agricultural products could seriously threaten human health. The present study measured diazinon residue in tomato, cucumber and melon by collecting samples from different areas including 2 regions for tomato (Mashhad and Shiravan), 6 regions for cucumber (Disfool, Jiroft, Kerman, Shirvan, Torbate-Jam and Mashhad), and 2 regions for melon (Shiravan and Torbate-Jam). Diazinon residues were determined using gas chromatography (GC) technique. Results showed that pesticide residue in melon samples from Torbate- Jam and Shiravan were 4.98 and 4.11 times more than the permited residue level, respectively. Cucumber samples collected from Disfool, Rafsanjan, Jiroft, Kerman and Shiravan were 6.1, 4.4, 4.2, 2.1, and 1.8 times higher than the permitted level, respectively. However, diazinon residue in cucumber and tomato grown in Mashhad were lower than permitted levels.

The city is identified as altered natural environment by excessive changes in nature and increasing presence of manmade structures. Urban green spaces are remnants of nature in this environment and play an important role in ascending the level of life quality in the city. In this study the effects of urban sprawl on quantity of urban green spaces in region 2 of Tehran municipality were studied comparatively in 1989 and 2002 using aerial photos interpretations and geographical information systems (GIS). The studies indicate a considerable decrease in urban green spaces with a more intensity in the northern parts of the region. The sub-region 8th had the greatest amount of decrease among 9 sub-regions and 6th sub-region had the minimum rate of decrease. Two general strategies are concluded from the results of this study: 1) the priority of conservation and support of the existing green and open spaces 2) establishing new green spaces in some parts of the region which benefit less environmental quality.

During the first decade after the Islamic Revolution of Iran, Plan and Budget Organization (PBO) embarked upon a series of studies titled "Regional Disparities Investigation" . They aimed at demarcating the country's regions based on indicators of socialeconomic- natural and infrastructure facilities. The results of these studies were instrumental in order for PBO to formulate national strategies of social equity. Attributed to it's prevailing rural economy, natural setting and diseconomies of spatial structure, Ghezel-Ozan watershed was identified as one of the most deprived regions of the country. The next step was taken by the Ministry of Construction Crusade which launched an investigation and planning project at the Ghezel-Ozan regional scale in 1993. The goal of this project was to explore underlying causes of the region's relative backwardness and to formulate policies and plans to alleviate the situation. Taking an environmental approach to regional development, this article attempts to elucidate relationships of determining resources such as water, soil, flora etc. to settlement patterns in the watershed. The main conclusions based on the findings of the project were : a) Unequal and sparsely scattered distribution of natural resources has been historically, the main determinant of appearance of thousands small villages, one forth of which is now deserted. b) Due to lack of sizable urban centers in the watershed which could assume roll of central places on the one hand, and unfavorable climate and terrain resulting in weak communication networks on the other, in addition of many deserted villages the remaining are greatly dependent upon services of outside urban centers. C) parallel to certain natural processes, economic activities such as traditional animal husbandry and agriculture are responsible for escalating resources deterioration. All in all, due to lack of planning commitments, the watershed has missed development opportunities embedded in it's both man made and natural settings.

Siah Keshim Wetland, declared as a protected region under category 7 in Ramsar Convention. In addition to its important attraction for different migrating birds, fishes and so on, it is also important from its location in part of Anzali Wetland from the environmental, tourisms and economical point of views. In recent years, unlogical progressive increase in trade, agricultural, municipal and industrial activities without planning have caused environmental damages in which its life has been threatened. In this research, physical, chemical and biological water analysis of six main rivers and the wetland have indicated heavy pollution effects of rivers water sheds to the wetland. The low level of dissolved oxygen, has shown anaerobic affinity in some parts of the wetland that necessitates implementation and control of a management program. Accumulation of different kinds of pollutants and nutrients, variation of pH, and concentration of sulfate has caused more problems in the watlend. In addition, the relative low level of pH and the possibility of heavy metals dissolution and H2S production in different parts of the wetland should not be ignored. High level of coliform due to sanitary wastewater discharges to the wetland and its affinity for eutrification and gradual death could not be discarded.

Land cover/use change induced by human activities, ignoring environmental constrains caused landscape degradation. The continuous land use change has also severe impacts on natural ecosystems. Therefore, in consideration with the negative effects of unsuitable use of land and land use change, knowledge and understanding about the changes is essential in environmental impact assessment for sustainable planning and land management .This study is for investigating the trends of changes in the landscape, in Neka Watershed. In order to provide land cover maps the satellite images of MSS 1972, TM 1992, ETM+2001 were applied and landscape metrics of class area, largest patch index, number and mean patch size were used to quantify landscape patterns. The analysis of landscape metrics revealed that the extensive replacement of agricultural lands and forests with rangelands and the results verified that increased patch number and decreased mean patch area were two important fragmentation indicators and the trend of degradation and fragmentation of the landscape was increasing. Therefore the results necessitated paying attention to the quality of land use and cover in the region for decreasing the natural resources degradation.

Solid wastes have been an inseparable part of human life and the production of the wastes, in different levels of quality and quantity, is considered to be one of the major challenging issues of the environment in this era. Air and water pollution and soil which is the result of the lack of correct management and lack of choosing appropriate landfills to bury the wastes, have all created some problems for the environment. Change the sentence. In order to decrease the negative outcomes of the wastes, it is essential to use the right tools and technology. One of the main parts of management in the urban solid wastes is finding an appropriate place in order to dispose the wastes. This study was done to locate the appropriate landfills in the city of Givi through using GIS technology. In this study the following parameters, criteria and rules for hygienic disposal on the basis of different standards such as Environment Conservation Organization, Ministry of Interior and worldwide experiences were identified, evaluated and selected: geology, infrastructure, seismic city of the areas, slope, land use, distance from rural and urban centers, soil plan of the area, hydrographic network plan, underground waters and the prevailing wind direction. Then, appropriate places in this area were identified according to national and international rules and standards and also by applying limiting factors through GIS. To integrate the layers and obtain the appropriate results, Bolin Logic was used. Through field visits, three locations for comparison and evaluation through hierarchical analysis process were selected and ultimately by doing closer studies on the selected locations and exerting appropriate weights on each of the locations, the final location will be selected.

Up to now, many different processes for landscape design such as Booth process (1983) have been introduced by landscape experts to aim a landscape project. The Booth process contains an orientation of actions in a landscape design project varying from project acceptance to presentation of constructed plan. The three adjusted sub-parts of Booth's landscape process stages which have been adjusted in a flowchart by the author of this article will be study in details. The aim of presenting such a flowchart is introducing and showing the interdisciplinary relationship between "landscape" and "surveying" experts in executing a design process. These three sub-parts contain some executing actions which are extracted from surveying which introduce this knowledge application in landscape design. These sub-parts contain "land surface features surveying and topographic map providing", "land technical design" and "setting out the design on the land". At the end, there are some suggestions for using new surveying instruments like GPS receivers in order to provide the topographic map in UTM coordinate system and transferring these landscape designs to this coordinate system.

Formal environmental education is very important and necessary for sustainable learning in each society. Therefore, students’ books must include environmental subject. In most of countries, Perception of educational planners and teachers toward environmental issues in students’ books play key role in development of this kind of education. The aim of this study is exploring perception of educational planners to environmental education in curriculum of guidance schools. A survey instrument is used to measure constructs of perception and attitudes.

The processes through which structure of ecosystems ends to its functions, according to the principles of environmental planning are called development. Since our environment consists of numerous ecosystems, and the complexity of action and reactions of developments emanates in cybernetic ecosystems, we need to use models, in order to predict and grasp a meaningful perception of the real world. But in some instances modeling and the use of models become too complicated, which potentially increase the uncertainty in predictions. This paper, is an attempt to elucidate these kinds of model like MLR, and AHP and to present some solutions like uses of Game Theory in spatial planning, reduced models in simplification of models, and matrix quantification of SWOT model. Finally, it is argued that model should act as a decision support system (DSS) in environmental planning.

The aim of this article is to know the influence of environmental factors on development of rural housing in a specified zone and to evaluate them by others influential factor relative to each other from dwellers' views and to prioritize them. For this purpose, the factors effective on development process of rural housing must be identified first. We try to introduce the final factors and evaluate them. Selection of factors is followed by Derivation of a conceptual framework effective on selection of proper rural housing development method, using the existing resources and Specification and interpretation of the factors chosen using the case study method. The main result is achieving the desirability of development method of each building with respect of functioning for the user. More over the value of each of the factors in the process of rural housing development in the region have been presented. After defining all factors effective on the proper method of rural housing development in the selected area, the contribution and the way that factors effect on formation of this method were defined. The contribution of each mentioned factor in fulfilling the desirability of the building functionally for user were measured by multiple variable regression analysis and based on exploited data. Statistic analysis has been done by SPSS software.

Multi store parking Site selection is one of the key problems in metropolitan city such as Tehran. This problem should be considered according to a series of criteria. The main aim of the paper is to determine proper sites for multi store parking using Fuzzy methods in GIS environment in first district of Tehran. To achieve the aim, parameters such as; distance from trip attractive center, distance from routes and communication networks, land price, suitable land use for parking establishment, distance form faults, and some other criteria were put in the fuzzy model. The results of this research showed that the OWA method in low risk and somehow trade-off mode represented the best result in according to aim. In this state, 6239.1 square meter of study area was selected as the high-rank area for establishing multi-store parking lots.

Today solid waste like air and water can’t across the city and state and become as a social problem. Of coerce unsuitable management solid waste can polluted the air by burning materials or by running the slug and penetrationto water resources, and can cause pollution. In general solid waste management means to collect and decrease solid waste generation by correct consumption pattern solid waste separation in origin by education and ….. problem of collecting and landfill of Tehran solid waste has been appeared by increasing the population and their activity. The method has been carry out research is questionnaire. Questionnaire is separated in two groups, like people and staff. In each questionnaire asked some questions and analysed by excel. The other method has been based on observation. It means we separated zone 3 in 4 groups vanak, jourdan, mirdamad and … then we have been made tables and 8 question for each box. Then these question has been analysis by Excel. Approximately, the situation of half of the boxes to the houses was good and half was bad. The situation of 70% of the boxes to the commercial area was good, and 30%, was average which means boxes were collect better in commercial areas. Appearance situation was 96% average. Waste near the boxes during the day was 99% good but at night were 63% bad, and 37% average. Volume of boxes in comparison with waste during the day was 99% good but at night were 62% bad and 38% average. With a view all 400 boxes which were bad need washing. Settlement of boxes in legs area in all 400 boxes was good. The situation boxes in comparison with generator population in all 400 boxes were average. These results has been that the physical area the boxes are good the volume and the way of collection of solid waste specially at night are bad.