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11.
Changes of biochemical properties and heavy metal bioavailability in soil treated with natural liming materials 总被引：5，自引：0，他引：5
Samy A. M. Abd El-Azeem Mahtab Ahmad Adel R. A. Usman Kwon-Rae Kim Sang-Eun Oh Sang Soo Lee Yong Sik Ok 《Environmental Earth Sciences》2013,70(7):3411-3420
This study evaluated the efficiency of naturally occurring lime-based waste materials (oyster shells, eggshells, and mussel shells) on immobilization of selected heavy metals (Cd and Pb) and a metalloid (As) in a contaminated agricultural soil. A 30-day incubation experiment was performed using soil mixture with natural liming materials or calcite (CaCO3) at 0, 1, 3, 5, and 10 wt %. Soil biochemical properties including pH, electrical conductivity (EC), exchangeable cations, organic matter (OM), total nitrogen (TN), microbial populations, and enzyme activities were determined to ensure the changes in soil quality during incubation. The results showed that the application of natural liming materials led to an increase in soil pH similar to that of CaCO3. Soil concentrations of Cd, Pb, and As extracted with 0.1 or 1 M HCl, and diethylene triamine pentacetic acid (DTPA) were decreased significantly after adding liming materials, accompanied by increased microbial population and enzyme activities of dehydrogenase, phosphatase, β-glucosidase, and arylsulfatase. Additionally, eggshells and mussel shells induced significant increases in OM and TN in the soil. Application of natural liming materials offers a cost-effective way to immobilize heavy metals and metalloids in soils. 相似文献
12.
Mahtab Ahmad Deok Hyun Moon Kyoung Jae Lim Christopher L. Shope Sang Soo Lee Adel R. A. Usman Kwon-Rae Kim Jeong-Hun Park Seung-Oh Hur Jae E. Yang Yong Sik Ok 《Environmental Earth Sciences》2012,67(4):1023-1031
Military shooting range soils contaminated by heavy metals have been subjected to remediation efforts to alleviate the detrimental effects of exposure on humans and the surrounding environment. Waste materials can be used as cost-effective soil amendments to immobilize heavy metals in contaminated soils. In this study, naturally occurring lime-based waste materials including egg shells, oyster shells, and mussel shells were assessed for their effectiveness toward heavy metal immobilization in military shooting range soil in Korea. Soil was treated in batch leaching experiments with 0, 2.5, 5, 10, and 15% of each lime-based waste material. The results showed that the lime-based waste materials effectively reduced water-soluble Pb at an application rate of 2.5% by weight of the soil. Increase in soil pH from 6.6 to 8.0 was considered to be the main chemistry of Pb immobilization, which was supported by the formation of insoluble Pb species at high pH values as confirmed by the visual MINTEQ thermodynamic model. In contrary, water-soluble Cu was increased in the lime-based waste material-treated soils when compared to the untreated soil. This was likely attributed to the formation of soluble Cu?CDOC (dissolved organic carbon) complexes as all lime-based waste materials applied increased DOC contents in the soil. Therefore, care must be taken in selecting the appropriate amendment for immobilizing metals in shooting range soils. 相似文献
13.
Nadeem Ahmed Anjum Mahtab Ritesh Agrawal P. Jayaprasad S. K. Pathan Ajai D. K. Singh A. K. Singh 《Journal of the Indian Society of Remote Sensing》2007,35(2):121-127
CARTOSAT-1 satellite, launched in May, 2005 is a dedicated along track stereo mission providing high quality data for topographic
and cartographic applications. The present paper describes the evaluation of the Cartosat-1 stereo data, mainly through the
generation and validation of DEM for moderately undulating and hilly areas. Photogrammetric techniques have been used for
generation of DEM and Orthoimage for two cases i.e. 1) using RPCs (Rational Polynomial Coefficients) and 2) using RPCs along
with ground control points. Root Mean Square Error (RMSE) in elevation values for the moderately undulating (Dehradun) and
hilly area (Shimla), are found to be 4.38 and 3.69m respectively. 相似文献
14.
Hesni Majid Askari Rezaie-Atagholipour Mohsen Zangiabadi Somaye Tollab Mohammad Amin Moazeni Mostaf Jafari Hosein Matin Mohammad Talebi Zafarani Ghasem Ghorbanzadeh Shojaei Maht Motlaghnejad Abbas 《海洋学报(英文版)》2019,38(12):43-51
Iranian nesting populations of the critically endangered hawksbill turtle(Eretmochelys imbricate) are some of the most important in the Indian Ocean. In this study, four of the most important hawksbill nesting grounds in the Persian Gulf, situated within three Iranian marine protected areas, were surveyed during nesting season,including Nakhiloo, Ommolgorm and Kharko Islands and the mainland beaches of the Naiband Marine-Coastal National Park(NMCNP). We present GIS maps of these key nesting grounds and describe sand texture of key nesting zones, along with conservation recommendations. About 9.2(28.3%) out of 32.5 km of all shores surveyed in this study were used by nesting hawksbill turtles follows: Nakhiloo: 1.4 km(52% of potential nesting area);Ommolgorm: 1.94 km(40%); Kharko: 3.4 km(28%), and NMCNP: 2.46 km(18.9%). The average nesting density was calculated as 131 nests/km at Nakhiloo, 76 nests/km at Ommolgorm, 7 nests/km at Kharko, and 15 nests per km at NMCNP. Highest nesting density was observed in Nakhiloo and Ommolgorm. It is thought that high hawksbill nesting density in these islands seems likely a result of limiting adequate nesting shores rather than the size of population, and also low density in Kharko and NMCNP more related to past and current pressures and low population density. With the exception of Ommolgorm Island, sands at the nesting grounds were well sorted.Grain size indicated that female hawksbill turtles in the Iranian Persian Gulf nest in sands that are generally mixed, with mean grain size ranging from coarse sands(0.4Φ;～0.5–1 mm) to fine sands(2Φ;～0.25 mm). We provide and discuss conservation recommendations and suggestions for future. 相似文献
15.
Zamanirad Mahtab Sarraf Amirpouya Sedghi Hossein Saremi Ali Rezaee Payman 《Natural Resources Research》2020,29(2):1127-1141
Natural Resources Research - Groundwater over-exploitation in arid and semiarid environments has led to many land subsidence cases. Immense economic losses incurred from land subsidence occurrences... 相似文献
16.
Delineation and analysis of clusters in orientation data 总被引：15，自引：0，他引：15
17.
V. N. Sridhar R. P. Singh Anjum Mahtab Ranendu Ghosh 《Journal of the Indian Society of Remote Sensing》2005,33(2):339-344
This paper reports a study on multi-temporal polarized response of wheat crop from spaceborne ADEOS-POLDER sensor over a homogeneous
wheat region of Punjab, India. Both the polarized as well as total reflectance of wheat were observed at different scattering
angles for two spectral bands i.e. 670 nm and 865 nm during crop growth from November to April in rabi 1996-97 season. Results
show that sun-target-viewing geometry plays an important role in polarization property. The top of atmosphere (TOA) polarized
reflectance is found to decrease exponentially with increasing scattering angle. Polarized reflectance of crop was found to
be an order of magnitude smaller in comparison to the total reflectance. An attempt was also made to model the observed polarized
behavior over an agricultural area using a theoretical simplified crop reflectance model and accounting for atmospheric molecular
(Rayleigh) contribution in the single scattering approximation. It was found that there was a decrease in the polarized reflectance
at the grain filling (heading) stage of wheat crop. This is in accordance with ground- based observations and can be due to
the reduction in the specular component of the reflected light during post-heading stage of the crop. 相似文献
18.
Saifullah Nadeem Sarwar Sadia Bibi Mahtab Ahmad Yong Sik Ok 《Environmental Earth Sciences》2014,71(4):1663-1672
Cadmium (Cd) is a highly toxic heavy metal and its presence in soil is of great concern due to the danger of its entry into the food chain. Among many others, proper plant nutrition is an economic and practicable strategy for minimizing the damage to plants from Cd and to decrease Cd accumulation in edible plant parts. The study was carried out to compare the effectiveness of soil and foliar applications of zinc (Zn) to minimize Cd accumulation in wheat grains. The results revealed that the exposure of plants to Cd decreased plant growth and increased Cd concentration in the shoots and grains of wheat, when compared with unexposed plants. Foliar application of 0.3 % zinc sulfate solution effectively decreased Cd concentration in wheat grains. Foliar application of Zn at a suitable concentration can effectively ameliorate the adverse effects of Cd exposure and decrease the grain Cd concentration of wheat grown in Cd-contaminated soil. 相似文献
19.
Mahtab Safari Shad Mahmoud Habibnejad Roshan Alireza Ildoromi 《Journal of the Indian Society of Remote Sensing》2014,42(1):107-117
Because of the difficulty of monitoring and measuring snow cover in mountainous watersheds, satellite images are used as an alternative to mapping snow cover to replace the ground operations in the watershed. Snow cover is one of the most important data in simulation snowmelt runoff. The daily snow cover maps are received from Moderate Resolution Imaging Spectroradiometer (MODIS), and are used in deriving the snow depletion curve, which is one of the input parameters of the snowmelt runoff model (SRM). Simulating Snowmelt runoff is presented using SRM model as one of the major applications of satellite images processing and extracting snow cover in the Ghara - Chay watershed. The first results of modeling process show that MODIS snow covered area product can be used for simulation and forecast of snowmelt runoff in Ghara - Chay watershed. The studies found that the SCA results were more reliable in the study area. 相似文献