Desert
Volume:18 Issue: 2, Summer - Autumn 2014

Qanat is one of the important inland aquatic ecosystems commonly containing freshwater in arid and semi-arid regions. There are 37 qanat chains in Kerman County in the Kerman province of Iran. During past years, some of them have been dried as a result of deep wells digging in their vicinities. The present study used morphomeristic analysis to characterize fishes and invertebrate fauna in the qanats of Kerman County. Seven fish species and seven invertebrate genuses were identified. All fishes were from the Cyprinidae family except for the mosquito fish (Poecilidae family). Capoeta aculata was the most common fish species in the Kerman county qanats. From the insect identified species, the Hydropsyche genus was found in all qanats and Simolium genus was found in more qanats. The incidence of insect species Rhitrogena sp., Liponeura sp. and Ecdyonurus sp. was related to the incidence of organic pollution. They were only found in high discharge water qanats such as Farmintin and Goharriz. This indicates that the high discharge water is necessary to provide adequate water quality for settlement of these species. The results showed that more biodiversity is observable in qanats having higher water volumes.

The estimation of instantaneous peak discharge is important for watershed management because there is a insufficient climatic and hydrologic data in countries such as Iran. Researchers have been forced to link constant parameters (geomorphology) and variable parameters (hydrology) to models with minimum dependence on climatic and hydrologic data for hydrologic estimation. The present study used a synthetic unit hydrograph at three drainage basins in the central Alborz watershed (Kan, Amameh and Mehran) and compared the results with peak discharge in the study areas to derive the best model. The results of the instantaneous peak discharge estimation were similar for each drainage basin. A comparison of the models using relative mean error (RME) and root of mean square error (RMSE) for the three drainage basins showed that the mean RME for GIUH was 21.31, for Snyder was 82.25, for SCS was 227.34, and for triangular was 231.27. The mean RMSE for GIUH was 12.76, for Snyder was 17.05, for SCS was 42.84, and for triangular was 43.62. This confirms that the best estimation was produced by GIUH, followed by the Snyder, SCS and triangular models.

Climate is a natural resource that effects decision making for selection of destinations in tourism and ecotourism. The relationship between climate and tourism is a complex one. But application of a climate index provides an ideal approach to understanding this complexity and is a useful tool for the tourism industry. In this study, a modified version of Mieczkowski''s (1985) Tourism Climate Index (TCI) for months was used for Kerman province to determine climate comfort ratings ranging from ideal to unfavorable. Data covering a network of 12 meteorological stations was used to compute a TCI for the study region. Then index evaluations in each city were classified according to one of the six annual TCI distributions presented by Scott and Mcboyle (2001). Results of modeling showed bimodal-shoulder peaks in seven stations namely (Anar, Rafsanjan, Zarand, Sirjan, Shahre-Babak, Bam and Kerman); two stations namely (Baft and Lalehzar) had summer peak, and three cities (Shahdad, Kahnouj and Jiroft) had winter peak. TCI scores for all months in the study stations were transferred into Geographic Information System to determine the most suitable areas and months for tourism activities in Kerman province.

Geographical bases have significant function in human settlements in terms of distribution and sustainability. This study attempted to provide an insight into the role of geographical bases in rural settlement distribution in arid areas. Accordingly, this study was done in the rural area of Khour-Biabanak, Naein city in Esfahan province. The methodology was that of a correlative research, to realize the study objectives through analysis of field, library and documentary information. Generally speaking, geographical bases fall into two main categories; natural and human, with a number of variables. This study applied 49 variables classified according to natural, economic, social and infrastructure related themes. Some natural and infrastructure bases such as water resources and road networks are assumed as important in terms of rural settlement distribution. However, the findings of this study reveal that some human based factors, such as the ratio of working people to total population and number of job opportunities, had a greater role in distribution and sustainability of rural settlements in arid areas. Other factors, including size of population, number of households and number of secondary schools were also significant variables that influenced service ranking in rural settlements in arid areas. The study concludes that such factors need to be given due consideration in planning for rural development in arid areas.

A decrease in natural resources and their non-uniform distribution can affect social relationships between residents of watersheds, creating conflict and shifting groupings. The present study used the network analysis method to test the hypothesis that change in hydrologic parameters and water shortages in the village of Tutang has led to the new groupings in the social cooperation network of the local population. Data was gathered by questionnaire. A cooperative network composed of village residents to resolve the water shortage was delineated using UCINET and Visone software. The results showed that past communication patterns based on kinship changed after the water shortage arose and led to the formation of new groupings among residents. Individuals who cooperated in resolving the water shortage experienced higher social power, authority, and status. The results emphasized the need to focus attention on the interactions between subsystems of a social-ecological system. Determined individuals with increased social power can be enlisted to solve the conflicts

The use of temporary runoff and underground dried-up water courses has been implemented by managers in recent years to compensate for water shortages in arid and semi-arid regions. One way to use this water is to set up an underground sandy dam in front of such water courses; selecting a suitable water course is the most important issue of such a purpose. In the present research, this matter was investigated using both library and field work methods during three stages in a part of the Gilan-e-Gharb basin. The following 11 variables were considered: lithology, structure, fault direction, length of water course, slope of water course, grade of water course, valley shape, granular of sediment, thickness of sediment, lithology of valley bed, and distance from habitation. First, 15 valleys were selected from aerial stereoscopic photos of 1:55000 over the hillsides dominating the plains of Gilan-e-Gharb; the variables considered were lithology, structure, fault direction, length of valley, slope of valley, and distance from habitation. Then, these 15 valleys were investigated through field study and paired comparison matrices considering the 5 factors of valley shape, granularity of sediment, thickness of sediment, lithology of valley bed, and grade of water course. As a result, 3 valleys over the hillsides of Mount Bar-e-Aftab were selected as suitable sites for the current study. The total reservoir volume for these 3 valleys was estimated by measuring the water volume of 1 cubic meter of sediment in a practicable and scientific method. Upon completion of an underground sandy dam project, between 2475 to 256 cubic meters of water could be stored in each valley.

Nowadays multicriteria decision making (MCDM) methods are a useful tool for investigating natural resources and to address problems related to hydro systems. The goal of this research was to assess the Daliri Standardization Method (DSM) to prioritize and make selections for application to MCDM. And to compare the DSM method with the Utility Additive (UTA) method. The (DSM) method, unlike the (UTA) method, lines up choices without incorporating a decision-maker. Moreover, by conditioned weights, linear or exponential functions, the choices partial additive function is formulated in the Lingo program and finally, the total additive function is used to make priorities among the choices. In this study, 47 sub-watersheds in eastern Khurasan province were evaluated according to 25-year return periods for flood, lag time and fatal-cost damage. Results of the (DSM) method were accompanied by all multi-component goals in subbasins based on real data. The utility function of each method was compared with data relating to the Kan river northwest of Tehran, and comparison showed that 80 percent of the results were the same, so the DSM method can be considered as more logical and sensible than the UTA method. This evaluation was made without consideration of site variation, so it can be used effectively in watershed flood management to prevent investment in low priority sub-basins.

The Kashan erg is one of the most important sand dune complexes in Iran. Being affected by wind erosion, the erg''s borderlands face numerous problems as a result of sand movement. To evaluate the risk of sands moving into residential areas near the Kashan erg, anemometry data from synoptic stations located in Kashan, Ardestan, Meimeh, Naeen, and Qom were collected and analyzed to calculate the sand rose and to determine the amount and direction of sand transfer. Annual and seasonal data from the past 40 years were studied. Based on the position of different stations and the prevailing direction of erosive winds at the stations under study, Kashan is more vulnerable to sand transfer than other areas, because the prevailing direction of erosive winds in Kashan is from the northeast and west, and the Kashan erg is located exactly northeast of Kashan. In this area, wind forces result in sand movement towards Kashan. Thus, Kashan is much more exposed to moving sand than the cities of Ardestan and Naeen. The cities of Qom and Meimeh are not at risk from moving sands. According to the morphology of the erg and sand rose calculations, most sand transfer occurs first in the erg''s vast sand dunes and then in the compound dunes in the center; it occurs less in the transverse dunes located north of the erg and in the linear ones south of it.

This study analyzed the relationship between the vertical distribution of root biomass and soil organic carbon (SOC) content in the arid shrub lands of Semnan province in Iran. Three sites were selected based on differences in canopy cover of Artemisia sieberi (5%, 10% and 15%). Average density of shrubs, root biomass and SOC were determined at different depths (0-20, 20-40, 40-60, 60-80 cm) in 20 quadrats at each site and are expressed on a per ha basis. Simple equations were used to calculate the relationship between SOC and root biomass for each site. Statistical analyses were conducted using ANOVA. The results showed that the root biomass and the SOC content generally decreased as soil depth increased. There was an acceptable relationship between root biomass and SOC at all sites. The proportion of SOC in the soil was found to be positively related to the vertical distribution of root biomass; 75% of total root biomass was found at 0-25 cm, while this same soil layer contained 48% of SOC.

There is a little room for doubt that Lake Urmia, which is the second largest permanent hyper saline lake in the world, is currently suffering from a lack of appropriate management strategy. Accordingly, this study was done using the SWOT matrix to analyze the key factors affecting declining water levels and increasing salinity. Results of group decisionmaking by brainstorming among a group of experts identified 17 internal factors (four strengths and 13 weaknesses) and nine external factors (five opportunities and four threats). Then four kinds of strategy groups were formulated by matching internal and external factors. And the most feasible policy was introduced from evaluations of Attractiveness Scores and Quantitative Strategic Planning Matrix (QSPM). These reality-based solutions can be applied to facilitate progress towards realizing the target vision. This information was used to select the best alternatives according to strategies based on weaknesses and opportunities (WO Strategies). This study illustrates that the existing water use pattern did not conform to the requirements necessary for sustainability. Furthermore, managerial-based strategies with the objectives of preserving surface and groundwater sources, orienting stakeholders towards implementing efficient water use pattern, adjusting water consumption with existing potential in the field and improving irrigation efficiency and reduction of losses can be applied to eradicate the ecological issues associated with Lake Urmia.