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Pasargadae complex had been the main center of Persian history during the Achaemenian period (560–330 bc), registered as one of the world heritage sites by UNESCO in 2004. This research is an attempt to recognize the natural setting
and landscape of Pasargadae during the Achaemenian period, in Iran. The method is based on the application of a multi-layer
technique. Collected data by fieldwork, especially in geology, hydrology, and hydrogeology, along with the analysis of aerial
data and satellite information provided the baseline information for preparing historic and environmental layers and have
made it possible to recognize a natural lakelet in the this area. The results show that the geometry of lakelet together with
the ancient river of Pasargadae had been the main elements that formed the character of the site; they were also important
in the locations of buildings in the Pasargadae complex. 相似文献
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Hamideh Nouri Pamela Nagler Sattar Chavoshi Borujeni Armando Barreto Munez Sina Alaghmand Behnaz Noori Alejandro Galindo Kamel Didan 《水文研究》2020,34(15):3183-3199
Urban green spaces (UGS), like most managed land covers, are getting progressively affected by water scarcity and drought. Preserving, restoring and expanding UGS require sustainable management of green and blue water resources to fulfil evapotranspiration (ET) demand for green plant cover. The heterogeneity of UGS with high variation in their microclimates and irrigation practices builds up the complexity of ET estimation. In oversized UGS, areas too large to be measured with in situ ET methods, remote sensing (RS) approaches of ET measurement have the potential to estimate the actual ET. Often in situ approaches are not feasible or too expensive. We studied the effects of spatial resolution using different satellite images, with high-, medium- and coarse-spatial resolutions, on the greenness and ET of UGS using Vegetation Indices (VIs) and VI-based ET, over a 780-ha urban park in Adelaide, Australia. We validated ET with the ground-based ET method of Soil Water Balance. Three sets of imagery from WorldView2, Landsat and MODIS, and three VIs including the Normalized Difference Vegetation Index (NDVI), Enhanced Vegetation Index (EVI) and Enhanced Vegetation Index 2 (EVI2), were used to assess long-term changes of VIs and ET calculated from the different imagery acquired for this study (2011–2018). We found high correspondence between ET-MODIS and ET-Landsat (R2 > 0.99 for all VIs). Landsat-VIs captured the seasonal changes of greenness better than MODIS-VIs. We used artificial neural network (ANN) to relate the RS-ET and ground data, and ET-MODIS (EVI2) showed the highest correlation (R2 = 0.95 and MSE =0.01 for validation). We found a strong relationship between RS-ET and in situ measurements, even though it was not explicable by simple regressions; black box models helped us to explore their correlation. The methodology used in this research makes a strong case for the value of remote sensing in estimating and managing ET of green spaces in water-limited cities. 相似文献
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Geological and Geochemical Investigation of Three Ophiolite‐Hosted Manganese Prospects,Southeast of Birjand,South Khorasan,East of Iran 
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下载免费PDF全文 Behnaz Barghi Ali Asghar Calagari Mohammad Hossein Zarrinkoub Vartan Simmonds 《Resource Geology》2017,67(4):414-425
The studied ophiolite‐hosted manganese prospects are located in southeast of Birjand, South Khorasan, in the east of Iran. The manganese ores within the ophiolitic sequence in this region occur as small discrete patches, associated with radiolarian chert and shale. Manganese ores in the host rocks are recognizable as three distinct syngenetic, diagenetic, and epigenetic features. The syngenetic manganese ores occurred as bands associated with light‐red radiolarian chert. The diagenetic Mn ores occurred as lenses accompanied by dark‐red to brown radiolarian chert. The epigenetic Mn ores occurred as veins/veinlets within the green radiolarian shale. The major manganese ore minerals are pyrolusite, braunite, bixbyite, ramsdellite, and romanechite showing replacement, colloidal, and brecciated textures. The high mean values of Mn/Fe (15.32) and Si/Al (15.65), and the low mean concentration values of trace elements, such as Cu (85.9 ppm), Ni (249.9 ppm), and Zn (149 ppm), as well as the high concentration values of Si, Fe, Mn, Ba, Zn, Sr, and As in the studied manganese ores furnished sufficient evidence to postulate that the sea‐floor Mn‐rich hydrothermal exhalatives were chiefly responsible for the ore formation, and the hydrogenous processes had negligible role in generation of the ores. The further geological and geochemical evidence also revealed that the ores deposited on the upper parts of the ophiolitic sequence by submarine exhalatives. The intense hydrothermal activities caused leaching of elements such as Mn, Fe, Si, Ba, As and Sr from the basaltic lavas (spilites). After debouching of the sea‐floor exhalatives, these elements entered the sedimentary basin. The redox conditions were responsible for separation of Fe from Mn. 相似文献
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Mahmoud Ahmadi Abbasali Dadashi-Roudbari Tayebeh Akbari-Azirani Behnaz Nasiri-Khuzani 《Theoretical and Applied Climatology》2020,140(3):963-982
Efficient and proper understanding of the state of the clouds regarding different seasons of the year will have profound effects on different economic and environmental sectors. The purpose of this study is to determine the hourly dissociation of ice and liquid clouds in Iran. To this end, cloud optical thickness (COT) data, as well as optical depth of clouds in two phases of liquid and ice were obtained and processed from 31 synoptic meteorological stations (1960–2015), MODIS data from Terra satellite during the years 2001 to 2011, and they were processed then. Next, using the RegCM4 model, the cloud fraction (clt) was simulated to accurately identify the cloud cover situation in Iran. The results showed that the maximum annual mean abundance of liquid and ice clouds was 18.95 days for the time 15:00 and 3.99 days for the time 06:00, respectively. Climatic zones of the Caspian and Persian Gulf coasts at 15 o’clock had the highest decreasing trend of liquid clouds. Ice clouds in all parts of Iran’s climate, with the exception of the eastern plateau, also declined. From south to north and east to west of Iran, the occurrence of ice and liquid clouds is increasing. Therefore, the spatio-temporal distribution of liquid and ice clouds in the country was also dependent on spatial components and latitude had the greatest impact. From the satellite and modeled data, the RegCM4 model has been able to detect the Monsoon phenomenon in southeastern Iran during the summer. CLT simulation in Iran has also shown that cloud cover in Iran fluctuates between 28 and 65% on average, with 81.5% of Iranian stations having a significant change in the amount of annual cloud cover. Correlation of liquid and ice clouds with precipitation showed that liquid clouds in summer and ice clouds in spring had higher correlation with precipitation in Iran. Northern coasts of Iran due to greater ascent mechanisms such as coastal compressors, north latitude atmospheric circulation systems, and maximum winds in the north and west of Iran due to the location of western systems entry and sufficient thermal gradient, had maximum ice clouds in the last half century. Also, south of Iran, despite having extended and great water-bodies, is less cloudy due to descending air in Hadley’s circulation (Hadley cell) of air. 相似文献
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Naser Hafezi Moghaddas Hadi Hajizadeh Namaghi Hadi Ghorbani Behnaz Dahrazma 《Environmental Earth Sciences》2013,68(2):487-497
Soil samples were collected from the agricultural lands of Golestan province, north of Iran and analyzed for 24 elements including eight toxic metals of As, Cd, Co, Cr, Cu, Pb, Se and Zn. Electrical conductivity, pH, organic matter, soil texture, calcium carbonate content as well as soil cation exchange capacity were also determined. The possible sources of metals are identified with multivariate analysis such as correlation analysis, principal component analysis (PCA), and cluster analysis. In addition, enrichment factors were used to quantitatively evaluate the influences of agricultural practice on metal loads to the surface soils. The PCA and cluster analysis studies revealed that natural geochemical background are the main source of most elements including Al, Co, Cr, Cs, Cu, Fe, K, Li, Ni, Pb, V and Zn in the arable soils of the province (more than 90 %), however, those soils which have been developed on the mafic and metamorphic rocks were considerably contributed on metal concentration (43 %). Calcium and Sr were constituents of calcareous rocks and Na and S were mainly controlled by saline soils in the north of the province. Loess deposits was also accounting for high levels of selenium concentration. Phosphorous was mostly related to application of P-fertilizers and organophosphate pesticides. The comparison of metal load and enrichment factor for dry and irrigated farmlands showed that Cd, Co, Pb, Se and Zn had higher concentrations in the irrigated lands where considerable amounts of agrochemicals had been applied. However, it also found that proximity of arable lands to urban and industrial areas resulted in higher Pb and Cd values in the irrigated agricultural sources relative to dry ones. 相似文献
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Preparing high-quality samples, which can fulfill testing standards, from weak and block-in-matrix conglomerate for laboratory tests, is a big challenge in engineering projects. Hence, using indirect methods seems to be indispensable for determination uniaxial compressive strength (UCS). The main objective of this study is to estimate the relation between sonic velocity (Vp), Schmidt hammer rebound number (SCH) and UCS. For this reason, some samples of weak conglomeratic rock were collected from two different sites of dam in Iran (Bakhtiari and Hezardareh Formations). In order to evaluate the correlation, the measured and predicted values utilizing simple and multivariate regression techniques were examined. To control the performance of the proposed equation, root mean square error (RMSE) and value accounts for (VAF%) were determined. The VAF% and RMSE indices were computed as 94.34 and 1.56 for the relation between Vp and UCS from simple regression model. These were 94.39 and 1.6 between SCH and UCS, while these were 97.24 and 1.34 for uniaxial compressive strengths obtained from multivariate regression model. 相似文献
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Behnaz Bigdeli Farhad Samadzadegan Peter Reinartz 《Journal of the Indian Society of Remote Sensing》2013,41(4):763-776
With recent technological advances in remote sensing sensors and systems, very high-dimensional hyperspectral data are available for a better discrimination among different complex land-cover classes. However, the large number of spectral bands, but limited availability of training samples creates the problem of Hughes phenomenon or ‘curse of dimensionality’ in hyperspectral data sets. Moreover, these high numbers of bands are usually highly correlated. Because of these complexities of hyperspectral data, traditional classification strategies have often limited performance in classification of hyperspectral imagery. Referring to the limitation of single classifier in these situations, Multiple Classifier Systems (MCS) may have better performance than single classifier. This paper presents a new method for classification of hyperspectral data based on a band clustering strategy through a multiple Support Vector Machine system. The proposed method uses the band grouping process based on a modified mutual information strategy to split data into few band groups. After the band grouping step, the proposed algorithm aims at benefiting from the capabilities of SVM as classification method. So, the proposed approach applies SVM on each band group that is produced in a previous step. Finally, Naive Bayes (NB) as a classifier fusion method combines decisions of SVM classifiers. Experimental results on two common hyperspectral data sets show that the proposed method improves the classification accuracy in comparison with the standard SVM on entire bands of data and feature selection methods. 相似文献
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Abbasi Hamid Delavar Majid Bigdeli Nalbandan Roya Hashemy Shahdany Mehdy 《Stochastic Environmental Research and Risk Assessment (SERRA)》2020,34(6):755-774
Stochastic Environmental Research and Risk Assessment - Adaptive planning in climate change condition is a significant challenge for effective management of water resources and agricultural... 相似文献
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