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11.
S. Maman L. OrlovskyD.G. Blumberg P. BerlinerB. Mamedov 《Journal of Arid Environments》2011,75(9):842-850
The shortage of fresh water in Turkmenistan may be partially alleviated by runoff water from takyrs. However, anthropogenic degradation of takyrs over the past few decades has reduced their efficacy as catchment areas. The main goal of this study was to map the spatial extent of takyrs and their change over time. Digital image processing of Landsat MSS and Landsat 7 ETM+ images were used to identify, map and classify the takyrs and estimate their overall area and degradation rates. Thereafter, a change detection procedure was applied. Results retrieved from Landsat MSS images of southern Turkmenistan (1972-1975) showed a total area of non-degraded takyr surfaces of ∼20,000 km2, whereas those from Landsat 7 ETM+ images (2002-2003) showed a total non-degraded takyr area of ∼16,000 km2. These include ∼8000 km2 which were degraded and ∼4000 km2 that were only detected by the ETM+ due to its improved spectral resolution. Accuracy was assessed by comparing the Landsat results with higher spatial resolution images of QuickBird. Additional ground points located with GPS measurements validated the classification results. We were thus able to assess the takyr areas degraded over the past decades, and find ∼16,000 km2 of non-degraded takyrs suitable for water harvesting. 相似文献
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A. Sh. Mukhtarov F. A. Kadirov V. A. Mamedov 《Izvestiya Physics of the Solid Earth》2010,46(6):524-528
In order to reconstruct the ground surface temperature history (GSTH) in the Kura depression from the data on borehole temperatures,
we selected two thermal logs, which met the requirements of the well temperature inversion into the GSTH. The temperature
gradients measured in these wells varied about 20 K/km, which is typical for the region of study. The borehole temperatures
were inverted into the ground surface temperatures in the past in accordance with the program developed by Po Yu Shen. It
was found that the ground surface temperature had increased by 1–2°C during the last century. The GSTH derived from the well
temperature inversion agrees with the climate temperatures measured at the Ganca meteorological station, which has been operating
since 1873. These results obtained for the Kura depression are consistent also with the results of similar studies in other
regions in the world. 相似文献
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A method is outlined for the determination of soil moisture content from remote sensing imagery, with consideration of its rapid fluctuation based on meteorological events and other factors (e.g., humus content and character of vegetation). The present paper is devoted to soil moisture detection in the visible, reflected-infrared, and thermal-infrared portions of the electromagnetic spectrum in irrigated portions of the Kura-Araks lowland in Soviet Transcaucasia, based on optical density measurements from image negatives, for the most part. Translated by Edward Torrey, Alexandria, VA 22308 from: G. V. Dobrovol'skiy and V. L. Andronikov, eds., Aerokosmicheskiye metody v pochvo-vedenii i ikh ispol'zovaniye v sel'skom khozyaystve: sbornik nauchnykh trudov [Remote Sensing Methods in Soil Science and Their Utilization in Agriculture: A Collection of Scientific Works]. Moscow: Nauka, 1990, pp. 183–189. 相似文献
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The middle Miocene continental fluvial sediments of the Sangaredi Group in the western districts of the Futa Jallon-Mandingo
bauxite-bearing province were initially more widespread. Their thickness in the axial zones of the main drainage systems (Paleocogon,
Paleotomine, etc.) attained 150 m. The lower, early Miocene steps of topography formed during the first phase of regional
neotectonic evolution were buried beneath these sediments by the end of middle Miocene. The sediments of the Sangaredi Group
underwent substantial epigenetic alteration in the glei geochemical setting with removal of iron and bleaching. At the second
stage of neotectonic uplifting and dissection, this low-Fe and high-Al protolith was again affected by lateritic weathering
with formation of unique sedimentary-lateritic bauxites. The underlying bedrock was also affected by bleaching and lateritization
with formation of high-quality infiltration-metasomatic bauxites with geliform cryptocrystalline structure and massive porcelainlike
or oolitic texture. Both classes of bauxites are high-quality and of great economic importance. 相似文献
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B. A. Mamedov 《Monthly notices of the Royal Astronomical Society》2008,387(4):1622-1626
Using the binomial expansion theorem, the simple general analytical expressions are obtained for the Voigt function arising in various fields of physical research. As we will seen, the present formulation yields compact closed-form expressions which enable the ready analytical calculation of the Voigt function. The validity of this approximation is tested by other calculation methods. The series expansion relations established in this work are accurate enough in the whole range of parameters. The convergence rate of the series is estimated and discussed. Some examples of this methodology are presented. 相似文献
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Mamedov V. I. Makarova M. A. Boeva N. M. Slukin A. D. Shipilova E. S. Bortnikov N. S. 《Doklady Earth Sciences》2020,492(1):291-296
Doklady Earth Sciences - In the course of additional exploration of the lower horizons of the unique Sangaredi deposit in West Africa, nonlaterized deposits of the Sangaredi series of all major... 相似文献
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The ground air of the bauxite deposit in West Africa was tested for its chemical composition. The obtained data provide the
first insight into the air effect on the mineralogical-geochemical zoning of the lateritic weathering profile. The air was
tested in areas with different geomorphologic features, which allowed us to study the effect of relief and landscape on the
ground-air formation. 相似文献