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Drought Forecasting in a Semi-arid Watershed Using Climate Signals:a Neuro-fuzzy Modeling Approach

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Journal of Mountain Science 2014年第6期11卷 1593-1605页

作者： Bahram CHOUBIN Shahram KHALIGHI-SIGAROODI Arash MALEKIAN Sajjad AHMAD pedram attarod Department of Watershed Management Sari University of Agriculture Sciences and Natural ResourcesSari 48181-68984Iran University of Tehran Faculty of Natural ResourcesKaraj 31585-3314 Iran Department of Civil and Environmental Engineering University of NevadaLas Vegas NV 89154-4015 USA

Large-scale annual climate indices were used to forecast annual drought conditions in the Maharlu-Bakhtegan watershed,located in Iran,using a neuro-fuzzy model.The Standardized precipitation Index(SpI) was used as a proxy for drought conditions.Among the 45 climate indices considered,eight identified as most relevant were the Atlantic Multidecadal Oscillation(AMO),Atlantic Meridional Mode(AMM),the Bivariate ENSO Time series(BEST),the East Central Tropical pacific Surface Temperature(NINO 3.4),the Central Tropical pacific Surface Temperature(NINO 4),the North Tropical Atlantic Index(NTA),the Southern Oscillation Index(SOI),and the Tropical Northern Atlantic Index(TNA).These indices accounted for 81% of the variance in the principal Components Analysis(pCA) method.The Atlantic surface temperature(SST:Atlantic) had an inverse relationship with SpI,and the AMM index had the highest correlation.Drought forecasts of neuro-fuzzy model demonstrate better prediction at a two-year lag compared to a stepwise regression model.

关键词：神经模糊模型半干旱流域干旱预测气候指数模糊建模方法热带大西洋南方涛动指数热带太平洋

Temperature variability in northern Iran during the past 700 years

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Science Bulletin 2018年第8期63卷 462-464页

作者： Vilma Bayramzadeh Haifeng Zhu Xiaoming Lu pedram attarod Hui Zhang Xiaoxia Li Fayaz Asad Eryuan Hang Key Laboratory of Alpine Ecology and Biodiversity Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100101 China Department of Wood Sciences Faculty of Agricultare and Natural Resources Karaj Branch Islamic Azad University Karaj *** Iron Department of Forestry Forest Economics Faculty of Natural Resources University of Tehran Karaj *** Iran CAS Centre for Excellence in Tibetan plateau Earth Sciences Beijing 100101 China Department of Botany Bacha Khan University Charsadda Khyber PakhtunKhwa 24420 Pakistan

Warming is significantly affecting ecosystems in dry-warm areas,such as the Middle East[1],but long-term climatic records are often scarce in these regions.One important proxy source of climate data is tree rings,which have contributed to understanding climate changes over the past millennium[1].Under the pAGES2K framework[2],a tree-ring network of the Eurasian continent

关键词：温度记录可变性伊朗气候数据生态系统温暖中东上下文

Response of platanus orientalis leaves to urban pollution by heavy metals

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Journal of Forestry Research 2019年第4期30卷 1437-1445页

作者： Esmaiel Khosropour pedram attarod Anoushirvan Shirvany Thomas Grant pypker Vilma Bayramzadeh Leila Hakimi Mazaher Moeinaddini Department of Forestry and Forest Economics Faculty of Natural ResourcesUniversity of TehranKarajIran Department of Natural Resource Sciences Faculty of ScienceThompson Rivers UniversityKamloopsCanada Department of Wood Sciences Karaj BranchIslamic Azad UniversityKarajIran Department of Horticulture College of AgricultureSaveh BranchIslamic Azad UniversitySavehIran Department of Environment Faculty of Natural ResourcesUniversity of TehranKarajIran

Atmospheric pollution is an important concern in urban environments.The impact of urban pollution on the physiological,biochemical and anatomical properties of leaves of oriental plane(platanus orientalis L.)was studied.The leaves were collected from an urban site(Tehran,Iran)and a non-urban forest park(Chitgar Forest park).Anatomical(stomata,parenchyma,and cuticle)and physiological(chlorophyll content,enzyme activities)properties were analyzed.The concentrations of Cd(cadmium),pb(lead),Ni(nickel),and Cr(chromium)in leaves were significantly higher and Zn(zinc)lower at the urban site relative to the forest park.Chlorophyll a,total chlorophyll,and carotenoid content in leaves of the urban site were significantly less than those of the forest park,but there was no significant difference in chlorophyll b.In addition,the activities of superoxide dismutase,catalase,ascorbate peroxidase,and guaiacol peroxidase in urban leaves were significantly higher than in the leaves of the forest park.In the urban area,leaves experienced a significant decrease in leaf surface area,stomata density,stomata pore area,epidermis,and spongy mesophyll thickness,but a significant increase in cuticle and palisade thicknesses relative to forest park leaves.The increase in enzyme activities may indicate that the trees are attempting to cope with increased reactive oxygen species(ROS)because of pollution-induced stress.Our study suggests that oriental plane trees alter their physiological and anatomical properties when living in a polluted urban environment.

关键词： Heavy metals Leaf anatomy Leaf physiology Atmospheric pollution

Wood anatomical changes due to uptake of cadmium and lead from contaminated soils in Acer velutinum seedlings

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Journal of Forestry Research 2012年第3期23卷 473-479页

作者： Zeynab Shahpoori Vilma Bayramzadeh Vahid Reza Safdari Manoochehr Khan Zarinkafsh Roghayeh Jirrodnejad pedram attarod Department of Soil Sciences Karaj BranchIslamic Azad UniversityKarajIran Departments of Forestry and Forest Economics Faculty of NaturalResourcesUniversity of TehranKarajIran

We investigated wood anatomical changes due to uptake and accumulation of cadmium and lead from contaminated soils in Acer velutinum Boiss seedlings. Two-year old seedlings were exposed for 180 days to soil concentrations with varying cadmium and lead concentra- tions. We measured three wood anatomical traits, average vessel area （gm2）, vessel number per square millimetre, and vessel lumen area per- centage （%）. For assessing the cadmium and lead accumulation, we measured the concentrations in the soil, leaf, stem, and root. Average vessel area and vessel lumen area percentage were similar （p〉0.05） in control and treated seedlings. Vessel number per square millimetre showed a decreasing trend from pith to bark in control and treated seed- lings, and the trend was more pronounced in treated seedlings. We con- clude that vessel number per square millimetre in A. velutinum is influ- enced by soil contamination. A. velutinum Boiss is not a suitable species for remediation of soils contaminated by cadmium and lead but it can be used as an indicator of the soil lead contamination, because lead concentrations in seedlings increased with increasing amount of lead in the soil.

关键词： Acer velutinum Cadmium Lead phytoremediation Vessel elements