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Modelling blue and green water resources availability in Iran 总被引：7，自引：0，他引：7
Knowledge of the internal renewable water resources of a country is strategic information which is needed for long‐term planning of a nation's water and food security, among many other needs. New modelling tools allow this quantification with high spatial and temporal resolution. In this study we used the program Soil and Water Assessment Tool (SWAT) in combination with the Sequential Uncertainty Fitting program (SUFI‐2) to calibrate and validate a hydrologic model of Iran based on river discharges and wheat yield, taking into consideration dam operations and irrigation practices. Uncertainty analyses were also performed to assess the model performance. The results were quite satisfactory for most of the rivers across the country. We quantified all components of the water balance including blue water flow (water yield plus deep aquifer recharge), green water flow (actual and potential evapotranspiration) and green water storage (soil moisture) at sub‐basin level with monthly time‐steps. The spatially aggregated water resources and simulated yield compared well with the existing data. The study period was 1990–2002 for calibration and 1980–1989 for validation. The results show that irrigation practices have a significant impact on the water balances of the provinces with irrigated agriculture. Concerning the staple food crop in the country, 55% of irrigated wheat and 57% of rain‐fed wheat are produced every year in water‐scarce regions. The vulnerable situation of water resources availability has serious implications for the country's food security, and the looming impact of climate change could only worsen the situation. This study provides a strong basis for further studies concerning the water and food security and the water resources management strategies in the country and a unified approach for the analysis of blue and green water in other arid and semi‐arid countries. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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Monireh POSHTKOOHI 《地球学报》2012,33(S1):55-57
The Iranian plateau comprises several continental blocks, which are clearly bounded by major faults. The sedimentary, stratigraphic, magmatic and metamorphic features of these blocks vary from one to the other. The continental crust of subject area in Central Iran was investigated in the past by several authors. It was concluded that this zone was metamorphosed, intruded by granites and faulted during late Precambrian Pan-African Orogeny (Ramezani and Tucker, 2003). 相似文献
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Monireh Poshtkoohi Talat Ahmad Ashwini Kumar Choudhary 《Journal of Earth System Science》2018,127(5):72
Precambrian magmatism in the Biabanak-Bafq district represents an extensive sequence of mafic magmatic rocks. Major, trace and rare earth elements reveal that the low-Ti basement mafic rocks are magnesium tholeiite and low-Ti cover a mafic rock belongs to Fe-tholeiite, whereas, the high-Ti alkaline mafic rocks, as well as dolerites, show much more Fe–Ti enrichment. Primitive mantle normalized trace element patterns show a relative enrichment of LREE and LILE and depletion of HFSE, but have an equally distinct continental signature reflected by marked negative Nb, Sr, P, and Ti anomalies. The composition of the intrusive rocks is consistent with fractional crystallization of olivine ± clinopyroxene ± plagioclase, whereas variations in the Sr and Nd isotope compositions suggest heterogeneous sources and crustal contamination. Low-Ti group samples contain a crustal signature in the form of high La/Yb, Zr/Nb, and negative \(\varepsilon \hbox {Nd}\) values. In contrast, high-Ti mafic magmatic rocks display an increase in La/Yb with a decrease in Proterozoic alkaline rocks recognized across the central Iran. The presence of diverse mafic magmatic rocks probably reflects heterogeneous nature of sub-continental lithospheric mantle (SCLM) source. The mafic magmatism largely represents magmatic arc or rift tectonic setting. It is suggested that the SCLM sources were enriched by subduction processes and asthenospheric upwelling. 相似文献
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In northeastern Sanandaj-Sirjan structural zone, the Takab-Ghorveh belt comprises a volcanic province which related to the collision between the Eurasian and Arabian continents. It contains almost Quaternary andesitic basalt to alkali basalt. These alkali basaltes show Strombolian type eruptions. The volcanic rocks in Bijar area represent a range of mafic magmas, re-vealed by mingling and mixing textures. A variety of features suggest that the lava flows before eruption from magma chambers, contaminated by continental crust. 相似文献
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Monireh POSHTKOOHI 《地球学报》2009,30(Z1):50-60
The study area is located in the northern part of Sanandaj-Sirjan zone in western part of Hamedan province in Iran. Estimation of times of these events is based on the 40K–40Ar age determination carried mainly on separated amphiboles, biotites and muscovites, and interpreted as the ages of their isotopic closure. Estimations range between 91 and 70 Ma (A. Baharifar et al., 2004). The Sanandaj–Sirjan zone of western Iran is a metamorphic belt (greenschist–amphibolite facies) that uplifted during late Cretaceous continental collision between the Afro-Arabian continent and the Iranian micro-continent. The Alvand plutonic mass is the most important aspect of igneous phenomena of this area. The plutonic rocks are generally confined to granitoidic such as granite, alkali-granite, monzodiorite, diorite, monzodioritic gabbro, monzogabbro, pegmatite, aplite etc according to IUGS clas-sification. 相似文献
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