فهرست مطالب

Desert - Volume:24 Issue:1, 2019
  • Volume:24 Issue:1, 2019
  • تاریخ انتشار: 1398/03/11
  • تعداد عناوین: 15
|
  • M. Ansari, F. Shekari *, M.H. Mohammadi, G. Végváric, B. Biró Pages 1-12
    Salinity stress is a brutal environmental stress which decreases the yield production of plants. Questions rise on which of the ionic stress or lack of water has deleterious effects on plants forage dry yield. Also, questions remain on whether the K+ reduction or Na+ accumulation is more important in forage dry yield reduction under salinity stress. The present experiment was conducted to answer the above questions in four alfalfa ecotypes. To do so, 6-7 weeks seedlings were irrigated with high salty water (EC=20dS m-1) and RWC, MSI, height, forage dry yield, Na+ and K+ were measured 1, 3, 6, 10, and 16 days after the salt shock. The results showed that one day after irrigation with saline water, all measured traits changed adversely. Salinity stress by decreasing K+ and increasing Na+ content reduced the growth of alfalfa plants. RWC reduction was less than K+ reduction or Na+ accumulation, so ionic stress had more deleterious effects on forage dry yield of alfalfa plants. Root cells had a higher content of K+ and Na+ ions compared with leaves, hence, they had a major defensive role against salinity stress. The K+/Na+ ratio reduction in saline condition was the main element for decreasing plant forage dry yield. The application of high salty water for irrigation of alfalfa plants is possible if there is a good subsoil drainage system to remove the leached saline water regularly from the soil. It is also suggested that foliar application of potassium may be ameliorate harmful effects of salinity stress in plant growth.
    Keywords: Potassium, Sodium, Irrigation with Saline Water, K+, Na+ Ratio, Alfalfa
  • Z. Rasaei, R. Mohajer * Pages 13-21
    Although fertility capability classification (FCC) has high performance in land evaluation and soil maps interpretation, so far it has been less attended in land evaluation studies. Therefore, qualitative (FCC method) and quantitative (Riquer index) land fertility capability evaluation for Wheat and Rice cultivation and comparison of Soil Taxonomy and WRB classification with FCC were chosen as this study objective. After field and laboratory studies, the soil map was prepared with the scale of 1: 50,000. Then, FCC and Riquer methods were used to determine the land fertility capability for Wheat and Rice cultivation for each of the soil map unites. Investigations showed that the FCC and Riquer methods have presented similar results and well interpreted and classified soils. The results of Riquer method indicated that the fertility capability of these lands is good except in gravelly and shallow parts, thus Wheat and Rice can be cultivated in these soils. A comparison of the current soil classification systems and the FCC results showed that the problems and inherent characteristics of studied soils were pointed well by the FCC system, whereas they have been expressed differently in Soil Taxonomy and WRB classifications. Gleyic condition, dryness and subsoil gravel are the most limitative factors to Wheat and Rice cultivation in this area.
    Keywords: Chaharmahal-va-Bakhtiari Province: FCC method: Riquer index: Soil Taxonomy, WRB, Gleyic condition
  • S. Ahmadi, H. Azarnivand, H. Khosravi *, P. Dehghana, M. Behrang Manesh Pages 23-31
    Drought is a disaster phenomenon especially in arid and semi-arid areas. Vegetation and its production play a main role in the social and economic issues in every country. In this study, Standardized Precipitation Index (SPI) and Normalized Difference Vegetation Index (NDVI) data have been used to monitor drought and the vegetation condition in Sonqor Abad in, Kermanshah province.  Meteorological station data in the study area was used to study the SPI as a drought index. The maps of NDVI and also land use changes were provided using Landsat-TM images for 2001, 2008 and Landsat 8 images for 2015 in ENVI software environment.  The obtained results showed that the land uses of cultivation and fallow have decreased and rangeland, urban and rock mass have increased. On the other hand, the dense of rainfall in the vegetation density has increased in this area during 2001 until 2015. Due to population growth and expansion of urban areas, the farm and garden lands have decreased around the city during this period. The correlation was found between vegetation density in mid-spring and the annual SPI of last year. Therefore, it can be concluded that there is a direct relationship between rainfall and the density of vegetation. By increasing the amount of rainfall and SPI, the vegetation density is increased. Based on the results, it is recommended that in addition to using meteorological data, satellite images should be used for monitoring the drought.
    Keywords: Drought, Vegetation, NDVI, SPI, Land Use Change
  • M. Mirhasani, N. Rostami *, M. Bazgir, M. Tavakoli Pages 33-42
    Wind erosion is considered as one of the main processes of land degradation in different parts of the world. Among the most effective ways to control wind erosion is to cover land surface with natural vegetation area. In this study, 3 replica soil samples were collected, at a depth of 0-3 cm, from various land uses in Dehloran, Ilam Province, Iran. Physical and chemical characteristics of soil samples were determined in the laboratory to allow the application of the ENVI_met Headquarter model commonly used to design biological windbreak. The threshold friction velocity (TFV) is the basic parameter for effective construction of a windbreak. To determine its values, a wind tunnel test was conducted. Based on simulation results with the pattern designed with Prosopis juliflora species, it was observed that the wind speed decreased in front of the windbreak but returned to the initial speed at a larger distance behind the windbreak. Therefore, the designed windbreak for this species is able to reduce the wind speed to a far distance while in the designed windbreak with Haloxylon aphyllumspecies the wind returns to the initial speed within a shorter distance. According to the results, the wind speed reduction is directly related to the height of windbreak. Moreover, the designed windbreak with P. juliflora species, more effectively reduce the wind speed and protect longer distances behind the windbreak; thus it can be proposed as a suitable windbreak for the study area.
    Keywords: Wind tunnel, TFV, Biological windbreak, ENVI-met
  • H.R. Naji *, M. Taher Pour Pages 43-49
    Dust storms are increasingly threatening the forest ecosystem in Western Iran. Due to its coverage of vast area of Zagros forest, the Quercus brantii is at the front line of the attack. Most tree deaths in this forest are from this species. This study aims to investigate the effect of simulated dust on wood development and leaf stomata from seedlings of Persian oak. The oak seedlings were put in a chamber and dusted from 9 a.m. until 6 p.m. at three different days with an interval of 12 days. They were under three increasing concentrations of dust (5000, 7000, and 9000 mg/m3). Leaf and wood samples of about 10 seedlings were collected, and the leaf stomatal features, growth ring and vessel features of both treated and untreated seedlings were examined. The results showed no variations in stomatal features except for pore aperture. As for wood features, growth ring, vessel number and diameter considerably changed. In treated seedlings, the growth ring and vessel diameter were smaller and the number of vessels was higher than in the untreated seedlings. No detection of differences in stomatal features could be tracked due to the short-period of treatment. The usual seedlings’ annual growth could be altered by treatment affecting on both annual growth ring and vessel features. To sum up, it can be concluded that dust storm has strong effect on seedling’s growth as can limit wood formation
    Keywords: Dust Storm, Wood Anatomy, Leaf Features, Growth Ring, Persian Oak
  • F. Kazemi *, F. Salahshoor, H. Farhadi Pages 51-59
    Application[Editor 321]  of biotic growth regulators (e.g. humic components) and appropriate mulches is recommended to improve turfgrass quality especially in arid andsemi-arid climate zones. However, limited number of studies have investigated their effect on lawn establishment. To investigate the effect of humic acid (HA) and selected mulches on characteristics of Festuca arundinacea in its planting stage, a factorial experiment based on a completely randomized block design with three replications was performed. The first factor was mulch types including vermicompost, leaf compost, cow manure,[Editor 322]  and sand (control) which were used to cover the seeds. The second factor was a HA solution (100 ml l-1) sprayed monthly over the period of the experiment. Plant height, fresh and dry weight of lawn clippings, photosynthetic index, leaf texture, and overall turfgrass quality were measured. Spraying HA significantly improved the measured factors except the dry weight and photosynthetic index of the plants. Among the mulches, vermicompost provided better impressions on improving the characteristics of this turfgrass species including 48% increase in fresh weight, 18% increase in height, 48% increase in total quality, and 10% reduction in leaf width of the turfgrass. This research can assist in developing knowledge for having high quality lawns in urban landscapes of arid and semi-arid environments.
    Keywords: Humic acid, Lawn, Mulch, Turfgrass quality, Vermicompost
  • H. Ahmady, Birgani *, J. P. Engelbrecht, M. Bazgir Pages 61-73
    A major question is whether different source regions across the Middle East account for changes in aerosol and dust particle characteristics, which impact Western Iran. Therefore, over a period of sampling from April 2017 to April 2018, dust particles were collected in Western Iran from different cities including Urmia, Sanandaj, Sare-Pole-Zahab, Dehloran and Abadan. The research aim is to compare the chemical compositions of dust and aerosol samples collected during the dust events from the different regions. Results of the analysis of components indicate that during dust events, the concentrations of major and trace elements change. The variability of chemical species during dust events, noted by tracking the dust plumes in satellite images, was also assessed and the results related to the different source areas, namely the dry lands of North-Western Iraq and the desert areas of South-Eastern Syria, some parts of Kuwait and KSA (around the Persian Gulf). Generally, the results show, different source regions across the Middle East have individual chemical compositions with different abundances.
    Keywords: Dust-Prone Regions, Dust Particles, Sediment Source Fingerprinting, The Middle East
  • A. Ghazi, A. Karimi *, G.H. Haghnia, S. Hojati Pages 75-85
    The objectives of this study were to determine the nature (aeolian vs. alluvial) and origin of sandy sediments in southwestern Iran (Khuzestan province) were collected in two transects across (NW-SE directions) and perpendicular to the Karkheh River, by using grain sized distribution characteristics, and the mineralogy and micro-texture of quartz grains of forty-five surface samples (0-30cm) at interval distances of ~1.5km. Standard sieves (0.5phi-intervals) were used for determining sand fractions. Silt and clay fractions were measured using the pipette method. Mineralogical composition and surface micro-texture of quartz grains of the selected samples were examined using a polarizing microscope and a scanning electron microscope, respectively. Mz (mean grain size) varied between 1.82 to 4.56f. The variations of Mz indicated the directional particle size fining the NW-SE transect. Sorting (dI) was 0.46 to 2f and with an average of 0.97f was poorly to well sorted. [FE1] The mean value of skewness (SKI) was 0.12 which ranged from -0.24 to 0.46 and skewed to fine particles. Kurtosis with mean values of 1.21 varied between 0.85 to 2.25, which indicated a slight leptokurtic. Grain size characteristics showed a disturbance near the river due to the fluvial processes. Quartz grains were rounded and evidences of both aeolian and fluvial processes were observed on the grains’ micro-texture. The mineralogy of sediments were similar to those in Saudi Arabia. This mineralogical similarity, as well as prevailing wind direction and grain size variations, indicates the possibility of the sediments to have likely originated from the Arabian plate.
    Keywords: Quartz micro-texture, Grain size characteristics, Sand mineralogy, Aeolian sand
  • F. Abdi, S.S. Moosavi *, M.R. Abdollahi, S. Tahmasebi Enferadi, M. Maleki Pages 87-97
    Triticum boeoticum wild wheat is a remarkable gene pool to environmental stress resistance. It is one of the most valuable species of the Triticeae tribe for improving wheat cultivars to moisture-stress. This research was carried out to assess the changes and responses of different traits of 10 accessions of Triticum boeoticum under non-stress and imposed moisture stress conditions in 2015 and 2016. Most traits were significantly affected by accession (A), water treatments (WT), and A×WT interactions. The accessions showed a high-level of genetic diversity for all traits, except peduncle weight. The accessions Tb5 and TB3 with the highest amount of economic yield per plant (EYPP) and water use efficiency (WUE), were less affected by the imposed moisture stress, while accession Tb6 with the maximum amount of water use (WU), main root length (MRL) and some phenological traits, were the most affected. The traits of WUE and main stem weight (MSTW) showed the highest and the traits of excised leaf water retention (ELWR), MRL and WU showed the lowest alignment with EYPP, respectively. The ability of producing assimilates (by increasing biological yield per plant and MSTW) and the ability of faster assimilates-remobilization into grains (by increasing harvest index and WUE), has been a neglected aspect of breeding wheat program under drought stress. In other words, the ability of a genotype to produce more assimilates and allocate it to grains (by increased BYPP and WUE, respectively) instead of belowground-traits, will result to increase EYPP. For example, the Tb6 ecotype, due to the allocation of more assimilates to underground parts, had little grain yield. While the traits of WUE, BYPP, seed number per main spike, seed weight per main spike (SWPMS) and main spike weight (MSPW) showed a positive and significant (P<0.01) correlation to EYPP, the traits of ELWR, MRL, day to heading and day to anthesis, had a negative and significant (P<0.05) correlation with yield. Generally, a high amount of WUE, MSTW, SWPMS, MSPW and peduncle weight; with a low amount of ELWR, phenological traits (except grain filling period), MRL, WU, and root to shoot dry weight ratio (RDWSDW) were suggested for the improvement of grain yield. SWPMS and MSPW were two main-components of grain yield in the favorite accessions (Tb5 and Tb3). Tb5 and Tb3 may have value for breeding wheat better adapted to moisture stress conditions in future.
    Keywords: Wheat, Wild relatives, Diversity, Root trait, Multivariate analysis
  • S.A.R. Seyed Jalali *, F. Sarmadian, Z. Mohammad Esmaiel, M. Navidi Pages 99-108
    Cation exchange capacity (CEC) is one of the most important soil attributes which control some basic properties of soil such as acidity, water and nutrient retaining capacity. However, the measurement of cation exchange capacity in large areas is time consuming and requires high expenses. One way to save time and expenses is to use simple soil covariates and geostatistical methods in mapping CEC. Therefore, the aim of the present research was to investigate the role of soil covariates in the improvement of spatial variability of CEC. The study area is located in southwest Iran on the Aghili plain, Gotvand, Khuzestan province. In this study, ordinary kriging and cokriging methods were used to predict CEC. 107 soil samples were gathered on a random grid of 200-700 m. 74 samples were used for training and 33 samples for testing the results. A principle component analysis was performed for covariate selection. Clay was selected as a covariate in cokriging due to high correlation between clay and CEC[FE1]  in the first principle component analysis. Based on the cross validation result of predicted dataset, RMSE and ME for cokriging were 2.16 and 0.03 cmol (+)/kg respectively, and 3.36 and 0.09 cmol (+)/kg for kriging, respectively. Based on these results, cokriging performed better than kriging for predition of cation exchange capacity since it used a covariate such as clay, for the improvement of CEC spatial prediction.
    Keywords: Geostatistics, Soil, Khuzestan, Gotvand
  • A. R. Karbassi *, M. Maghrebi, R. Lak, R. Noori, M. Sadrinasab Pages 109-118
    Long marine sedimentary cores can be effective in paleo-climate reconstruction. The present research aims at analyzing  the temporal variation of temperature as an important climate parameter and also variations in metal concentrations (As, Ba, Cd, Li, Mo, Mg, Mn, Na, Pb, Sr, Zn, Fe, Ca, Al) of two long sedimentary cores at the Persian Gulf back to the Holocene. The obtained results revealed that the average elemental concentrations, apart from Ni, Sr, Ca and Na, are less than the shale value in both sedimentary cores. Moreover, the amount of   varies from -1.31 versus 1.02 in Bushehr, to -1.69 versus 1.56 in Bandar Abbas sedimentary cores, respectively. In addition,  change from -3.63 Vs -2.02 in Bushehr to -3.79 Vs -1.36 in Bandar Abbas sedimentary cores, respectively. Abrupt change in  and  can be seen in both sedimentary cores at two different periods (3000 to 5000 and 8000 to 9000 years ago). The maximum increase in temperature in sedimentary cores was at 0.4°C per 100 years in Bushehr and 0.01°C per 100 years in Bandar Abbas. The minimum  temperature reached to -0.8°C per 100 years in Bushehr to -0.02°C per 100 years in Bandar Abbas sedimentary cores. Compared to the previously obtained temperatures in this research, there has been temperature changes in the last 40 years in the Persian Gulf, which indicates that the recent rate change in sea water temperature has been unprecedented.
    Keywords: Persian Gulf, Sediment core, Paleo temperature, long-term metals concentration
  • Z. Rafieemajoomard, M. Rahimi *, Sh. Nikoo, H. Memarian, S.H. Kaboli Pages 119-132
    In this research, two techniques of pixel-based and object-based image analysis were investigated and compared for providing land use map in arid basin of Mokhtaran, Birjand. Using Landsat satellite imagery in 2015, the classification of land use was performed with three object-based algorithms of supervised fuzzy-maximum likelihood, maximum likelihood, and K-nearest neighbor. Nine combinations were examined in terms of scale level (SL10, SL30, and SL50) and the nearest neighborhood (NN3, NN5, and NN7) in an object-based classification. Ultimately, the validity was evaluated through the usage of two disagreement components including allocation disagreement and quantity disagreement. Results of maximum likelihood classification showed higher overall inaccuracycompared to images categorized based on fuzzy-maximum likelihood and object-based nearest neighbor algorithms. The SL30-NN3 object-based classifier decreased the quantity disagreement by 290% compared to the maximum likelihood and 265% compared to fuzzy-maximum likelihood classifiers. For allocation disagreement, these values were equal to 36% and 19%, respectively. Thus, object-based classification had a better performance in land-use classification of Mokhtaran basin.
    Keywords: Maximum likelihood classifier, fuzzy-maximum likelihood classifier, K-nearest neighbor object-based classifier, Land use, Landsat imagery
  • F. Amirimijan *, H. Shirani, I. Esfandiarpour, A.A. Besalatpour, H. Shekofteh Pages 133-141
    One of the important issues in the analysis of soils is to evaluate their features. In estimation of the hardly available properties, it seems the using of Data mining is appropriate. Therefore, the modelling of some soil quality indicators, using some of the early features of soil which have been proved by some researchers, have been considered. For this purpose, 140 disturbed and 140 undisturbed soil samples were collected from Jiroft, southern Kerman, Iran. Some physical and chemical properties of soil, for example, sand, silt and clay percentage, organic matter (OM), calcium carbonate (CaCO3), electrical conductivity at saturation (ECe), porosity (F), and bulk density (BD) were measured using standard methods. Some soil physical property indicators, including plant available water (PAW), relative field capacity (RFC), air capacity (AC) and saturated hydraulic conductivity (Ks) were also calculated. Using the hybrid algorithm of principle component analysis-artificial neural network (PCA-ANN), the calculated indicators were predicted by the easily available properties. The results showed that PCA-ANN had an acceptable accuracy in the modelling of soilphysical quality. The coefficient of determination (R2) of training and testing data for PAW, RFC and AC were 0.82 and 0.81, 0.90 and 0.79, 0.99 and 0.99, respectively. The optimization of Ks did not have the desired results. In other words, the R2 values of the training and testing data for this indicator were equal to 0.25 and 0.13, respectively.
    Keywords: Aeration capacity, Plant available water, Relative field capacity, Sustainable agriculture
  • Z. Feizi, A. Keshtkar *, A. Afzali Pages 143-151
    The main portion of water demands of arid regions like Kashan Plain, Iran supply by groundwater wells. This research was conducted to assess the groundwater quality as well as modelling and mapping groundwater quality in the study area using geosatistics and deterministic techniques. Five water quality parameters, including Electrical Conductivity, Sodium Adsorption Ratio, Total Hardness, Total Dissolved Solids and pH, were applied to determine the irrigation and drinking water quality index using the Wilcox diagram and WHO standards. The final map indicated that the groundwater quality increased from north to south of the study area. The areas located in the centre, south and eastern south of the study area had the optimum quality for irrigation and drinking purposes. Furthermore, based on the results of zoning using the Wilcox diagram determined that ground water quality of the study area 22%, 42% and 36% were good, medium and non-suitable, respectively
    Keywords: Groundwater quality, Modelling, Geostatistic, Deterministic, Zoning
  • M. Shahini Shamsabadi, I. Esfandiarpour, Borujeni *, H. Shirani, M. Bagheri Bodaghabadi, M.H. Salehi Pages 153-169
    Soil classification systems are very useful for a simple and fast summarization of soil properties. These systems indicate the method for data summarization and facilitate connections among researchers, engineers, and other users. One of the practical systems for soil classification is Soil Taxonomy (ST). As determining  soil classes for an  entire area is expensive, time-consuming, and almost impossible, this research has tried to predict the soil classes in each level of the ST system (up to family level) by using the data of 120 excavated pedons and some auxiliary parameters (such as derivatives of digital elevation model, i.e., DEM) in Shahrekord plain, central Iran. For this reason, the decision tree model was encoded and implemented in the MATLAB software for three conditions: use of soil properties, auxiliary parameters, and its combination. According to the results, soil class prediction error by using soil properties, auxiliary parameters, and its combination was estimated to be 0, 3.33 and 0% for order and suborder levels; 0.83, 15 and 0.83% for great group level; 3.33, 22.5 and 3.33% for subgroup level and 30, 52.5 and 30% for family level, respectively. In addition, the use of kriging maps of soil properties (instead of 120 observational points) decreased the prediction error of the modeling in all levels of the ST system. It seems that the effect of auxiliary parameters (in comparison to soil properties) is not very significant for predicting soil classes in low-relief areas.
    Keywords: Soil classification, Kriging maps, Digital soil mapping, Sensitivity analysis