Desert
Volume:14 Issue: 1, Winter - Spring 2009

Soil, is a reclamable and sustainable source. it is the basis of survival and it’s implication, should be performed on the basis of productivity identification according to scientific and technical rules, we can protect this valuable source, and increase it’s productivity and usage. Nowdays, saline soils cover nearly 14.6% of the country area. Study areas (Kashan’ playa) have saline and alkali soils. Identification of these soils and their’s reclamation and implementation for different usage, is very important, especially, they have abundant water resources. They have important influence on establishment and development of plants. Therefore, we started qualitative and quantitative pedological research. First, we prepared cover map as georeference with Ilwis 3.3 software. We overlaied cover map and georeference geological map. We determined 12 working units, and then we took samples from units. Physico-chemical factores such as EC, Gypsum%, soluble cations and anions, organic matter, CaCO3 % and etc, determined from the depths of 0-10, 20-40, 40-80 of plant types(working units, QM, QC) in February and july. Result shows, Na, Mg, SO4, K, pH, Cl, CO3, HCO3, CaCO3, SAR, CEC rates decreased and Gypsum and Ca% rates increased, from the Lake to uplans. Also, the soil’s texture was changed from clay sandy loam to sandy loam. At last, was drew Soil’s salinity map according to the soil taxonomy, it is in entisol order, aquent suborder, endo aquent greatgroup and typic endoaquent subgroup. According to the results, the soil isn’t suitable for dry farming and aquaculture (very bad class (class V)). Study area, covered by halophyte plants and it will be appropriate to develop and improve with other halophytes. It should be protected from animals. Especially camels that conserve soil structure and poor plant cover.

Various resistances to salinity are due to plants genetically variations, and selection on the basis of one factor will not be a suitable criterion in measurement of resistance to salinity, therefore in choosing resistant varieties, it is necessary to notice to a set of resistant indexes to salinity, creating changes in physiology, anatomy and morphology of plant species. This research was conducted using a factorial experiment based on CRD design with 4 replication at research institute of forests and rangelands. Experimental treatments included a combination of three species (S.rigida, S.dendroides and S.richteri) along with 7 salinity levels of 0, 100, 200, 300, 400, 500, and 600 mM concentrations. The purpose of this research was to investigate metabolites, accumulation in terms of compatibility or incompatibility value for salinity stress in three species. The results of physiology features measurement demonstrated that S.dendroides water potential is more than two others. Comparing of the measured characteristics, averages demonstrated that S.rigida and S.dendroides have reposed in one statistical group in terms of proline concentration and significant different have with S.richteri. Also, increasing salinity levels leads to the highest proline concentration in S.richteri in salinity treatment of 400 mM. In all three species, it is seen that salinity increase reduces plants soluble carbohydrates concentration rate and it reveals that salinity have a negative effect on these materials.

Shahdadroud River is one of the most important rivers in Kerman province that during previous years has been threatened by drought and anthropogenic pollution. This river supplies some parts of drinking water of Kerman city and some vicinity villages. The main objective of the present study is consideration of pollution situation of the river; for this purpose, limnological and biological studies of the river were carried out seasonally in 2007. Four sampling stations including Vameghabad (station 1), Bamoghavemat (station 2), Sharifabad (station 3) and Mehrechenar (station 4) were determined based on limnological standard method along the river; afterwards sampling of invertebrates (biological index) and water quality (BOD) were performed seasonally during study period. The results showed that station 1 is free of pollution while the station 2 is the most polluted region at the river; because the station 1 has no pollutant resource but the station 2 receives wastewater of rainbow trout fish culture center directly. Based on findings of biomonitoring and water BOD measurement, Shahdadroud River has relatively high-polluted situation and is classified in? -mezosaprobe class.

Many agricultural researches have been performed to improve soil productivity. Nitrogen (N) and Phosphorus (P) are essential elements which are utilized by the plants in large amounts. Phosphorus can be provided by applying chemical fertilizers. Microorganisms convert insoluble phosphate to the soluble form and some bacteria such as rhizobacteria play an important role in this process. This research was designed to determine the plant growth promoting (PGP) abilities, especially phosphate solubilization, of different isolates of indigenous rhizobia and their effect on growth characteristics of wheat, corn and alfalfa. 446 isolates belonging to different species of rhizobia were examined regarding inorganic and organic P solubilization, siderophore, auxin (IAA and homologes), 1-aminocyclopropane-1-carboxylate (ACC) - deaminase and hydrogen cyanide (HCN) production. It was found that 7% of the strains could produce HCN, 86% siderophores and 74% IAA and 44% were able to solubilize phosphorus. 8 rhizobial isolates were found as superior plant growth promoting rhizobacterial (PGPR) strains. Green house experiments using these strains evaluated the promoting effects of different strains on legume (alfalfa) and non-legume (wheat and corn) plants. Total biomass to the above mentioned plants was determined and the amount of N, P and iron (Fe) in shoots were also measured. The results were analyzed by the RCBD contrast method using SAS software V6.12. In conclusion, the green house experiment showed that P1B2 and a mixture of 4 plant growth stimulating rhizobacterial strains are the best suited as growth promoting inoculants.

Non-renewable natural resources play an important role in sustainable development of developing countries such as Iran. However, since the natural resources should be preserved for future generations, proper use of such resources seems mandatory. Women are one of the prime users of natural resources in developing countries. The purpose of this study is to assess the conservational behavior of rural women and factors influencing such behaviors regarding destruction, protection, and restoration of desert areas of Khuzestan province in Iran in a one-year period from Sep 2006 to Sep 2007. Rural women living in desert areas were interviewed in the process of data collection using multi-stage random sampling techniques. The results revealed that rural women played an essential role in the protection, restoration and destruction of natural resources. Moreover, there was no significant relationship between rural women’s personal characteristics and their activities in utilization of natural resources. This implies that destruction of natural resources is not attributed to rural women's intentions. However, human basic needs such as searching for a place to live, unpredictable weather conditions, unawareness of conservational facts, financial difficulties, large-sized families, overgrazing, and using woods as fuel were the main reasons for destruction.

Erosion and sedimentation are the most complicated problems in hydrodynamic which are very important in water-related projects of arid and semi-arid basins. For this reason, the presence of suitable methods for good estimation of suspended sediment load of rivers is very valuable. Solving hydrodynamic equations related to these phenomenons and access to a mathematical-conceptual model is very difficult and in most cases, necessary data for these models are not available. On the other hand, most of the widely-used experimental methods are not accurate-enough. The principles of wise method are: using the hidden knowledge in the data; effort to extract intrinsic relations between data; and generalizing them to other situations. Artificial neural network is one of the most important methods of artificial intelligence in which by inspiring from the model of human brain while performing training process, data-related information are stored into weights of network. The aim of this research is using MLP (Multi-Layer Perceptron) neural network to obtain sediment rating curve. After entering input patterns into the network and defining a neuron for input and a neuron for output layers and performing repeated trial and error, optimum architecture (topology) of MLP network was defined as a network with 5 neuron for hidden layers and Hyperbolic tangent activation function for the first and second hidden layers and Linear function for the third hidden layer.

Stochastic model for synthetic data generation is not available for daily flows of intermittent streams. Such a model is required in the planning and operation of structures on an intermittent stream for purposes where short time flow fluctuations are important. In this study a model is developed for such a case. The model consists of four steps: determination of the days on which flow occurs, determination of the days on which a flow increment occurs, determination of the magnitude of the flow increment, and calculation of the flow decrement on days when the flow is reduced. The first two steps are modeled by Markov chain. In the third step, flow increments on the rising limb of the hydrograph are assumed to be gamma distributed. In the last step an exponential recession is used with two different coefficients. Parameters of the model are estimated from the observed daily stream flow data for each month of the year. The model is applied to a daily flow series of 20 years’ length. It is seen that the model can preserve the short-term characteristics (The ascension and recession curves and peaks) of the hydrograph in addition to the long-term characteristics (mean, variance, skew ness, and zero flow percentage).

Millets are important agricultural crops for arid regions due to short life span and their resistance to salinity and drought conditions. In Iran, three main species of millets including proso millet (Panicum miliaceum), foxtail millet (Setaria italica) and pearl millet (Pennisetum glaucum) are cultivated in Shouthern Khorasan province, eastern Iran. In order to assess inter-specific genetic variation for salt tolerance at vegetative and reproductive stage, an experiment was conducted in split plot based on completely randomized block design. Nine genotypes of these millets collected from four different regions of the Shouthern Khorasan province (Ghaen, Sarayan, Nehbandan, and Birjand) were subjected to three levels of salinity stress (1.5, 5.5, and 9.5 dS/m). Although the yield and other yield related parameters of millets decreased by salinity stress, this reduction was more prominent only at high level of salinity (9.5 dS/m). Remarkable differences among same species from different areas were observed. Growth and yield capacity of three millet species from Birjand were also different. Of three millets, pearl millet from Birjand followed by foxtail millet, showed maximum yield potential under both salt stress and normal conditions. Of genotypes of foxtail millets, genotype from Sarayan exhibited maximum growth and yield potential under saline conditions. In contrast in proso-millets, genotype from Ghaen showed higher salt tolerance. Thus, salt tolerance varies in three millets from different regions, which could be further explored in future research.

This paper presents a robust approach using artificial neural networks in the form of a Self Organizing Map (SOM) as a semi-automatic method for analysis and identification of morphometric features in two completely different environments, the Man and Biosphere Reserve “Eastern Carpathians” (Central Europe) in a complex mountainous humid area and Yardangs in Lut Desert, Iran, a hyper arid region characterized by homogeneous repetition of wind-eroded landforms. The NASA Shuttle Radar Topography Mission (SRTM) has provided Digital Elevation Models (DEM) for over 80% of the land surface. Version 3.0 SRTM data provided by the CGIAR-CSI GeoPortal are the result of substantial editing effort on the SRTM DEM produced by NASA. Easy availability of SRTM 3 arc second data promoted great advances in morphometric studies and numerical description of terrain surface features as shown by many literature references. The goal of this study was to develop a new semi-automatic DEM-based method for geo-morphometric feature recognition and to explore the potential and limitation of SRTM 90 meter data in such studies. The 3 arc seconds data were re-projected to a 90 m UTM grid. Bivariate quadratic surfaces with moving window size of 5×5 were fitted to this DEM. The first derivative, slope steepness and the second derivatives minimum curvature, maximum curvature and cross-sectional curvature were calculated as geo-morphometric parameters and were used as input to the SOMs. Different learning parameter setting, e.g. initial radius, final radius, number of iterations, and the effect of the random initial weights on average quantization error were investigated. A SOM with a low average quantization error was used for further analysis. Feature space analysis, morphometric signatures, three-dimensional inspection and auxiliary data facilitated the assignment of semantic meaning to the output classes in terms of geo-morphometric features. Results are provided in a geographic information system as thematic maps of landform entities based on form and slope. Geo-morphometric features are scale-dependent and the resolution of the DEM limits the information, which can be derived. The results demonstrate that a SOM is an efficient scalable tool for analyzing geo-morphometric features as meaningful landforms under diverse environmental conditions. This method provides additional information for geomorphologic and landscape analysis even in inaccessible regions and uses the full potential of morphometric characteristics.

A significant deficiency of most computer models used for stream floodplain analysis is that the locations of structures impacted by floodwaters, such as bridges, roads, and buildings, cannot be effectively compared to the floodplain location. This research presents a straightforward approach for processing output of the HEC-RAS hydraulic model, to enable two- and three dimensional floodplain mapping and analysis in the ArcView. The methodology is applied to a reach of Polasjan River Basin, located in Iran central plateau. A digital terrain model is synthesized from HEC-RAS cross-sectional coordinate data and a digital elevation model of the study area. The resulting surface model provides a good representation of the general landscape and contains additional detail within the stream channel. The results of the research indicate that GIS is an effective tool for floodplain mapping and analysis.

The whole blood potassium concentration has shown the bimodal distribution in sheep, which has been classified into LK and HK types; HK allele is recessive to LK with a single gene inheritance. This polymorphism showed different behavior in different environment, which could be due to adaptation process. This research was conducted on the Zel and kermani breed research station, which Kermani breed Research Station has been located in a hot and dry climate with saline drinking water for animals and Zel breed research station has been located in a humid climate with normal drinking water for animals. Kermani breed Sheep: The whole Blood potassium concentration of 188 animals ranged from 8 - 44 m eq/l. The curve of shown that the sheep could be divided into two subpopulation via LK having 8-18 m eq/l of K+ and HK having 23-44 m eq/l of K+ with mean of 12.086±0.2 m eq/l of K+ in the LK type and with mean of 32.614±0.5m eq/l of K+ in the HK types. The frequency of HK gene was found to be 0.902. Concentration of sodium, calcium in whole blood were also determined, the mean and range of blood sodium concentration were 1737.36 and 343-5000.04 ppm respectively. The relationship between potassium and sodium concentrations in whole blood of sheep was significant. And negative estimated phenotypic correlation around -0.19 which was significant. The mean of whole blood sodium concentration was 3020.9 ppm and 2672.5 ppm for LK and HK respectively. Remarkable differences in calcium and magnesium concentrations were not recognized between LK and HK types. Zel breed Sheep: The frequency distribution of blood potassium concentration in the sheep population is presented as a frequency curve. It is seen from the monomodal nature. The curve that the sheep couldnt be divided into two subpopulation and all of animal has shown LK genotype. Blood potassium concentration ranged from 183.15 to 480.1ppm in Zel sheep and the Mean value of blood potassium concentration of Zel LK Animals was 277.37 and all of the zel animal were LK The ferquency of LK gene was found to be close to 1 in Zel sheep.The relationship between potassium and sodium concentration in whole blood of sheep was significant. And negative estimated correlation around –0.35 which was significant. The mean of whole blood sodium concentration was 2806/1 ppm for LK sheep. animals with HK phenotype have active Na-k-pump (i.e. concentration of Na and K in cell regulate with consume energy) but the animal with LK phenotype, concentration of Na and K regulate with simple diffusion and Na-K-pump is semi activeTherefore to regulate of Na and K concentration in cell, the animal with HK genotype can better survive dry climate with nearly saline drinking water.

This paper presents a quantitative account of vegetation–environmental factor relationships in arid rangelands. Vegetation cover was recorded using Braun-Blanquet combined abundance-cover scale in each quadrat. Within each quadrat, one profile was dug and soil samples being taken at 0-20cm and 20-100cm depths. Under study physical-chemical characteristics included texture, lime, organic matter, soil moisture content, saturation moisture, EC and pH. Five vegetation groups were identified after the application of Two Way Indicator Species Analysis (TWINSPAN) and Detrended Correspondence Analysis (DCA) methods including: A: Salsola richteri-Aelorupes littoralis; B: Zygophyllum eurypterum-Haloxylon ammodendron; C: Artemisia sieberi-Zygophyllum eurypterum; D: Ammodendron persicum-Stipagrostis pennata; E: Artemisia aucheri-Amygdalus scoparia. Canonical Correspondence Analysis (CCA) was used in a direct gradient analysis of the vegetation with the environmental variables. The results of CCA showed that first axis represented a landscape and edaphic gradient; it was positively correlated to soil texture and soil saturation moisture; it was negatively correlated with elevation and slope. The second axis represented mainly a soil moisture-salinity gradient; it was positively correlated with EC and soil moisture content. The results showed that those environmental factors that affect water availability were the most effective environmental factors in the distribution of vegetation groups in arid rangelands.