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1.
Groundwater over-exploitation has been increasing in Iran. Competing demands have grown in the face of perennial water shortages, a situation which has been exacerbated by drought conditions in the past decade. This paper describes the strategy development process recently undertaken in South Khorasan, Iran, in which the inclusion of stakeholder views was central to the approach. It involved government officials and various public and private sector interest groups. Particular efforts were made to involve well irrigators, who are likely to be heavily impacted by changes required to reduce groundwater pumping to a sustainable level. The paper concludes with a discussion of lessons learned. 相似文献
2.
The hydrochemical characteristics of groundwater in the southern parts of Tehran Province are considered. Twenty-three sampling stations were selected and major anions/cations, electrical conductivity and pH were detected. Sulfate and chloride were found as major anions, while no specific dominant cation was determined. More than half of the samples were found to be unsuitable for drinking purposes, due to high concentrations of anions/cations. Regarding agricultural use, almost all samples were classified as having high-risk levels of salinity, while for alkali hazard considerable risks were observed in most cases. Generally, an increasing trend of salinity is observed from northwest to southeast of the study area. Such increase may be justified by the adjacency of the Iran central desert and salt lake to the southern boundaries of the study area. Extended use of sulfate-containing fertilizers may also play a key role in justifying the high sulfate concentration in comparison to other anions. 相似文献
3.
A. Abbassi A. Nasrabadi M. Tatar F. Yaminifard M.R. Abbassi D. Hatzfeld K. Priestley 《Journal of Geodynamics》2010,49(2):68-78
Inversion of local earthquake travel times and joint inversion of receiver functions and Rayleigh wave group velocity measurements were used to derive a simple model for the velocity crustal structure beneath the southern edge of the Central Alborz (Iran), including the seismically active area around the megacity of Tehran. The P and S travel times from 115 well-located earthquakes recorded by a dense local seismic network, operated from June to November 2006, were inverted to determine a 1D velocity model of the upper crust. The limited range of earthquake depths (between 2 km and 26 km) prevents us determining any velocity interfaces deeper than 25 km. The velocity of the lower crust and the depth of the Moho were found by joint inversion of receiver functions and Rayleigh wave group velocity data. The resulting P-wave velocity model comprises an upper crust with 3 km and 4 km thick sedimentary layers with P wave velocities (Vp) of ～5.4 and ～5.8 km s?1, respectively, above 9 km and 8 km thick layers of upper crystalline crust (Vp ～6.1 and ～6.25 km s?1 respectively). The lower crystalline crust is ～34 km thick (Vp ～ 6.40 km s?1). The total crustal thickness beneath this part of the Central Alborz is 58 ± 2 km. 相似文献
4.
Impact of major organophosphate pesticides used in agriculture to surface water and sediment quality (Southern Caspian Sea basin,Haraz River) 总被引：3，自引：3，他引：0
Touraj Nasrabadi Gholamreza Nabi Bidhendi Abdolreza Karbassi Peter Grathwohl Nasser Mehrdadi 《Environmental Earth Sciences》2011,63(4):873-883
Organophosphate pesticides are compounds that are not only toxic to both humans and wildlife but also difficult to degrade
under natural environmental conditions. In Iran, agricultural practices are strongly dependent on the use of pesticides due
to climatic and soil conditions, thus posing a potential risk to groundwater quality standards. Evaluating the concentration
of organophosphate pesticides namely diazinon, fenitrothion, dichlorvos, ethion, profenofos, malathion and azinphos methyl
in water samples in May (low precipitation rate), December (high precipitation rate) as well as the concentration in sediments
along the Haraz River is taken into consideration in this study. Generally the pesticides concentration in water samples are
relatively higher in May in comparison with that in December; this fact may be due to two major reasons: the first reason
is attributed to the prompt raining after the treatment period of most orchards and dry farming lands that will terminate
in more wash out of such pesticides towards the branches and main river channel, while the second reason may be considered
as the less river water dilution rate in May because of lower precipitation rate. Furthermore, the relatively higher concentrations
in downstream stations may be contributed to more intensified agricultural (specially rice paddies), urban and rural land
uses in this region in comparison with upstream areas which contain mainly dry farming, grazing lands and orchards with relatively
lower loads of pesticides. Additionally, as the Henry’s law constant of all pesticides considered in this study are relatively
low, volatilization may not be regarded as an important route of dissipation. Diazinon, azinphos methyl and dichlorvos showed
the highest water concentrations in comparison with other pesticides that may be justified by their extended use within the
basin during last decades. Based on the chemical properties as well as remarkably higher values in sediment samples in comparison
with water ones, it is concluded that the two pesticides, ethion and fenitrothion, persist in the environment due to non-degradable
tendencies. Although the concentration of mentioned pesticides is not so high in the water samples, more precautions must
be considered in their future use. Regarding the sorption coefficient variation alongside the river, the higher values in
upstream and central parts may be attributed to the higher potential of different types of erosion regarding deeper slopes
and also sand, gravel and carbonate mining activities at the banks and also river bed in such regions which is considered
as an anthropogenic disturbance. In case of central parts, in addition to mentioned reasons, the existence of coal outcrops
in the geologic texture of the study area may also be considered as a key role in augmentation of the sorption coefficient.
Finally, the dominant clayey and loamy soils containing more organics may be attributed as the major reason of sorption tendency
in downstream. 相似文献
5.
T. Nasrabadi G. R. Nabi Bidhendi A. R. Karbassi H. Hoveidi I. Nasrabadi H. Pezeshk F. Rashidinejad 《Environmental Geology》2009,58(4):693-700
Sungun mine is the largest open-cast copper mine in northwest of Iran and is in the primary stages of extraction. The influence
of mining activity on the quality of regional groundwater has been taken in to consideration in this study. Accordingly, sampling
was done from 22 springs in the study area. The concentrations of major anions and cations as well as Al, Cu, Cd, Cr, Fe,
Mn, and Zn were determined for all 22 spring samples in mid-August 2005. The results showed that the concentrations of most
of these elements were below the USA Environmental Protection Agency (EPA) limits; however, Al and Fe concentrations are considered
to be more than limits in a couple of samples. Despite the fact that geological formations are highly weathered and fractured,
the dissolution of minerals within the study area is low. This may be justified by the relatively high alkalinity of local
underground water which keeps metals in solid phase and does not let them enter dissolved phase. Additionally, this may be
attributed to the high velocity of groundwater flows, which do not give enough time for minerals to dissolve. Correlation
coefficients among water chemistry components were determined and the weighted-pair group method was chosen for cluster analysis.
Accordingly, high correlation among Al, Fe and Cr, Cd ,and Cu, sodium absorption ratio (SAR) and Na as well as total hardness
(TH), Ca, and Mg were observed. The chemical characteristics of water compositions on the basis of major ion concentrations
were evaluated on a Schoeller and Piper diagram. Accordingly, the dominant type of water in the region is considered to be
Ca-HCO3 (calcium-bicarbonate type). However, this type of water is also rich in Na, K, and especially Mg. Regarding Schoeller diagram,
the current status of local underground water is good for drinking purposes. By commencing mining excavation with designed
capacity in near future, the minerals will come into contact with air and water resulting in dissolution, especially in ponds,
which, in turn, will increase the concentration of toxic metals in groundwater. Considering future uses of this water including
for drinking, irrigation, industrial purposes, etc., precautions must be taken in to consideration. 相似文献
6.
Saberali Seyed Farhad Shirmohammadi-Aliakbarkhani Zahra Nastari Nasrabadi Hossein 《Theoretical and Applied Climatology》2022,148(3-4):1217-1238
Theoretical and Applied Climatology - Water scarcity is the key challenge in arid regions, which exacerbates under climate change (CC) and must be considered to assess the impacts of CC on cropping... 相似文献
7.
Variations in crustal thickness in the Zagros determined by joint inversion of P wave receiver functions (RFs) and Rayleigh wave group and phase velocity dispersion. The time domain iterative deconvolution procedure was employed to compute RFs from teleseismic recordings at seven broadband stations of INSN network. Rayleigh wave phase velocity dispersion curves were estimated employing two-station method. Fundamental mode Rayleigh wave group velocities for each station is taken from a regional scale surface wave tomographic imaging. The main variations in crustal thickness that we observe are between stations located in the Zagros fold and thrust belt with those located in the Sanandaj–Sirjan zone (SSZ) and Urumieh–Dokhtar magmatic assemblage (UDMA). Our results indicate that the average crustal thickness beneath the Zagros Mountain Range varies from ～46 km in Western and Central Zagros beneath SHGR and GHIR up to ～50 km beneath BNDS located in easternmost of the Zagros. Toward NE, we observe an increase in Moho depth where it reaches ～58 km beneath SNGE located in the SSZ. Average crustal thickness also varies beneath the UDMA from ～50 km in western parts below ASAO to ～58 in central parts below NASN. The observed variation along the SSZ and UDMA may be associated to ongoing slab steepening or break off in the NW Zagros, comparing under thrusting of the Arabian plate beneath Central Zagros. The results show that in Central Iran, the crustal thickness decrease again to ～47 km below KRBR. There is not a significant crustal thickness difference along the Zagros fold and thrust belt. We found the same crystalline crust of ～34 km thick beneath the different parts of the Zagros fold and thrust belt. The similarity of crustal structure suggests that the crust of the Zagros fold and thrust belt was uniform before subsidence and deposition of the sediments. Our results confirm that the shortening of the western and eastern parts of the Zagros basement is small and has only started recently. 相似文献
8.
This letter proposes a nonlinear version of the eigenspace separation transform (EST) for subspace anomaly detection in hyperspectral imaging. The EST is defined in terms of the eigenvectors of the difference correlation matrix (DCOR) obtained using the data from the two classes. Using ideas found in the machine learning literature (i.e., the kernel trick), a nonlinear version-kernel EST (KEST)-is achieved by expressing the DCOR in terms of dot products in feature space and replacing all dot products with a Mercer kernel function that is defined in terms of input data space. Experimental results indicate that KEST outperforms many other commonly used subspace anomaly detection algorithms. 相似文献
9.
G. R. Nabi Bidhendi Ph.D. T. Nasrabadi H. R. Sharif Vaghefi H. Hoveidi 《International Journal of Environmental Science and Technology》2006,3(3):281-287
During the recent decades, the increasing trends in nitrate ion concentration in ground water sources have meant more research to find effective procedures for the prevention of even more water contamination by nitrogen sources. In this study a pilot was designed to examine the application of biological method for eliminating nitrate from the water of well No.903 of Mehrabad Airport, Tehran, Iran. Design, installation and running processes were done from April to November 2003. A fixed biological bed containing five-centimeter trunk pipes 16 mm in diameter were installed in the reactor and the system was operated with upflow current. Instead of Methanol, Acetic acid was used as the carbon source because of its easier acceptance by the public, lower price and availability as well as easier storage. The pilot was run in different hydraulic retention times from 48 h up to one hour. Considering economical, operational and maintenance factors, retention time of 2 h was determined to be optimum, in which 77% nitrate removal was achieved. Considering a ratio of 2 for COD/N, inlet COD of about 140 mg/L and the optimum retention time, COD removal of about 80% is also accomplished in this process. The amount of nitrite concentration, pH values, COD and turbidity is also evaluated versus different hydraulic retention times. 相似文献
10.
Nematchoua Modeste Kameni Roshan Gh R Tchinda René Nasrabadi T Ricciardi Paola 《Journal of Earth System Science》2015,124(1):269-281
Journal of Earth System Science - The foremost role of a building is to assure the comfort of its occupants. The thermal comfort of a building depends on the outdoor climate and requires a demand... 相似文献