Environmental Sciences
Year:2010 | Volume:7 | Issue:3|Papers Count:11

Morphometric and molecular studies were performed on the three species and two varieties of Alopecurus. Numerical taxonomic studies were performed on 14 populations using 37 morphological characters. Clustering and PCA ordination separated the species studied in different clusters. Factor analysis identified the most variable morphological characteristics to be used in Alopecurus species delimitation. Out of ten RAPD primers used, five primers produce 115 bands. Six bands were common to all three species while the other bands were polymorph. Some bands were specific to A. myosuroides, while some other bands were specific for A. textilis and may be considered as loci for discriminating between these two species. UPGMA clustering and PCO ordination of the Alopecurus species based on RAPD data showed the species distinctiveness supporting the morphological results. A. arundinaceus also showed greater similarity to A. myosuroides in its molecular characteristics indicating the use of RAPD data in Alopecurus species delimitation.

Soil pollution is receiving greater and greater attention due to its direct impact on soil, water and public health. Remediation of soil is an important means of restoring soil back to natural condition. The present work was aimed to examining a method of soil decontamination by means of biodegradation which is of crucial ecological significance as its basic mechanisms are based on natural processes. A high percentage of hydrocarbon reduction was obtained during nutrient and bulking agent stimulation. During the first 30 days, the first-order TPH degradation rate constant (k1) was lower for the treatment without nutrients (natural attenuation) followed by the augmentation, augmentation plus stimulation and stimulation treatments respectively.

The effectiveness of prescribed fire as a range management tool was examined in this study in the Yazd province of Iran. One hectare of land was divided into four 20 x 125 m blocks. Blocks were split into five 20 x 25 m experimental plots. Seasonal burning was randomly applied on each plot in 2004. One plot was also left unburnt as a control. Data were collected in 2005 and 2006 and analyzed. The results show that the response of species to fire varies within the season as well as among seasons. The minimum burning effect on vegetation cover was observed for the most desirable plant (Salsola rigida) in response to winter fire treatment. Fire eliminated both Artemisia sieberi and Stipa barbata, the two other important species found on the range. Reduction of undesirable species, such as Noaea mucronata and Cousinia deserti was also considerable. The percentage cover of other undesirable species, i.e. Scariola orientalis, did not change significantly (p<0.05). We concluded that, although it burning eliminated some species, it could not eradicate all undesirable species. It also failed to promote the desired species in terms of vegetation cover. So, at least in the short term, burning is not considered a range improvement tool for steppe rangelands in Iran.

Achieving sustainable architecture may be feasible by using renewable energies. Solar power can be exploited in building via photovoltaic and collectors to produce electricity and heat and it will lead to GHG reduction. Building integrated photovoltaic (BiPV) systems can form a cohesive design, construction, and energy solution for the built environment. PVs produce electricity and have special aspects that can be utilized. The expressive and impressive aspect of a photovoltaic system designed and applied on the envelope of the buildings can not be ignored and the architect should appreciate PV's abilities to perform as an exterior material as well. Designing a BiPV needs a team in which everyone plays his/her own role to reach the maximum output through the system. This paper will analyze the best architectural form and specification of a BiPV in Tehran. In this research diagrams of annual and seasonal total of global radiation in Tehran will be produced. With regard to diagrams the best tilt angle will be discussed. Finally, some basic forms such as cube, prism and box will be analyzed to receive the maximum solar radiation and an isosceles triangle for the best choice.

Species richness in relation to crop plants is analyzed within the families of higher plants. Three groups have been made: (1) more than 10.000 species (5 families), (2) 1.000 to 10.000 species (50 families), (3) less than 1.000 species (20 families). Thus about 224.000 species from the estimated 250.000 species of higher plants have been included in this study. According to Hanelt and IPK (2001), altogether 7,000 species of crop plants exist. There is a positive correlation (r = + 0.56) between the number of crop plants and species diversity of the families. Important crop species within the selected families are indicated.

Cities are complex and dynamic entities which are the main habitat of mankind. Nowadays cities are facing various challenges that threaten their quality and consequently that of urban residential areas. Developing relevant indicators is a vital step toward assessing these environments’ quality and can led to better decision making. The aim of this paper is to develop a tool comprising relevant indicators and to assess their relative importance for measuring the environmental quality of dwellings and urban neighborhoods. Impetus for the research was a need to inform planning and policy decisions in the Tehran metropolitan area. Residents of two Tehran neighborhoods participated in this study. During interviews, respondents were presented with five tasks: an inventory task, an importance selection task, a grouping task, a ranking and rating task for groups of attributes, and finally, a ranking and rating task for attributes within each group. After acquiring the needed data, attribute weights were calculated using four weight estimation methods. Next, the effects of neighborhood, sex, and age on the observed differences in attribute weights were examined, and a Comparison between the methods of attributes weight calculation was conducted. Based on two cluster solution methods, attributes were assigned to different clusters. These resulting clusters were then used to design the empirical model of urban environmental quality. In the end, after comparing the results of current study with those of previous studies, some amendments are suggested to be incorporated in revision of Iranian urban planning process, and some implications are presented for urban development policy.

A pot experiment was conducted to determine the phytoextractive ability of alfalfa plants both inoculated (I) and non-inoculated (I0) with Glomus mosseae under different combinations of heavy metal pollution. Alfalfa inoculated and non-inoculated plants were exposed to Cadmium (Cd), Lead (Pb), Cobalt (Co), Cd*Co, Cd*Pb, Pb*Co and Cd*Pb*Co in a factorial experiment. The heavy metal concentrations in the leaves, stems, shoots and roots were measured. In inoculated and non-inoculated plants, contamination concentration in shoots was higher than in root. Findings indicated that in the triple metal treatment (Cd*Pb*Co) inoculated plants were preferred. This showed that G. mosseae tolerated intensive contamination and transferred contaminants to alfalfa shoots. These results suggest that alfalfa inoculated plants are potentially suitable for phytoextraction of heavy metals in multiple heavy metal stress.

Flooding due to Caspian Sea level rise (CSLR) resulting from climate change may have serious ecological and socio-economic consequences. According to estimates from the Caspian Environment Programme (CEP), global warming until 2016 may cause a relative CSLR in Iranian coastal area of 20–120 cm. Rising the Caspian Sea level will not only inundate low-lying coastal regions, but it will also contribute to the redistribution of sediment along sandy coasts. In the present paper the possible impact of a CSLR of this magnitude on coastal habitat types is discussed based on topography at the Anzali Lagoon area in the North of Iran. Coastal marshes are susceptible to accelerated CSLR because their vertical accretion rates are limited and they may drown. As the Anzali Lagoon convert to the Caspian Sea, tidal exchange through inlets increases, which leads to sand sequestration on tidal deltas, erosion of adjacent barrier shorelines, and change the ecological conditions. The CSLR is expected to cause a change in groundwater level, a horizontal displacement of vegetation zones and a reduction in area, depending on accretion rate (sedimentation), local topography and inland land-use.

Parse (Persepolis) in Farvardin plain and Pasargadae in Marghab plain (two ancient cities in Fars Province) are well-known World Heritage archeological sites dating back to the Achaemenid period (560-330 BC), located in South-Central Iran. The present protective buffers for each site have been defined without any consideration of the natural and cultural landscapes that are the major criteria playing unique roles in their development. The area between Parse and Pasargadae along the Sivand River and Tang-e Bolaghi valley hosts significant natural, cultural and historical landscapes in which the above mentioned two sites are only two small representative heritages among the vast integrated landscape indicating‎ a spatial-temporal-cultural  association. The results of this study are: (1) By studying the historical, natural and cultural context and consistency of Parse- Pasargadae region, the identification of a more suitable protective margin for Parse- Pasargadae, cultural landscape as a unified concept and also to prevent its destruction. (2) Identifying criteria for the cultural landscape (3) Recognition that the Qashqa'i pastoralists are a special Persian cultural index that has preserved this culture for thousands of years.

A high priority has been placed in Iran in recent years on developing non-oil sources of income and tourism has been identified as one important area of the economy for development. The development of niche types of tourism such as ecotourism or cultural tourism – both the subject of this paper - is clearly in line with the public policy objective of developing non-oil sources of income. Environmental protection is an obligation on the government under Principle 50 of the Constitution of the Islamic Republic. It is therefore appropriate to consider what role the country’s vast cultural heritage resource can play in ensuring more environmentally sustainable forms of tourism development. Since even ecotourism developments can have negative environmental consequences by development of other forms of low intensity tourism (including cultural tourism) must be an important element in Iran’s policy agenda in this area. The promotion of cultural tourism in Iran should aim therefore to build on the positive impacts while minimising the negative ones. Policies for development of cultural tourism should also take into account the principles and objectives of sustainable development which are set out here within the context of tourism projects. A further reason to look at the role of cultural heritage in this respect is its intricate relationship with the natural environment, as evidenced by the 1972 Convention on the Protection of the World Cultural and Natural Environment of UNESCO. It should be remembered that heritage is a very broad concept that encompasses within its scope landscapes, archaeological sites and built environments as well as cultural practices and knowledge. All of these are relevant to the sustainable development and management of tourism. It also has a potential for contributing to sustainability in itself. This article will therefore consider the cultural heritage – as a tourism resource base - from all of these dimensions.

Urban Design and Landscape Architecture are designated as new arts /sciences that are formed through a combination of different artistic and scientific disciplines. The formal emergence of urban design happened in 1960's while landscape architecture existed from the beginning of 20th century. Success of these fields even after a century can mainly attributed to their focus on environmental quality of public realms in cities. The modernity of these two fields and activities regarding their goal and their view towards the aspects of the public domain, have resulted in ambiguous definitions which have made distinguishing them difficult. This article reviews the background features of the two fields such as definitions and approaches to understanding concepts and signifies the separating and identification points with suitable suggestions at the end. The results of this work show that the differences of the two fields, are related to the "scale and functional domain", "intrinsic emphases on particular environmental variables" and their "backgrounds". The identification points also depend on their association with architecture, urbanism and environmental design and management as the most important task.