The northeastern coast of the Caspian Sea is one of the youngest territories for plant colonization in Kazakhstan,and the flora of the most recent portion of this coastal area,the New Caspian marine plain,was chosen t...The northeastern coast of the Caspian Sea is one of the youngest territories for plant colonization in Kazakhstan,and the flora of the most recent portion of this coastal area,the New Caspian marine plain,was chosen to study phytogeographical characteristics of plant species,especially as related to alien origin and invasive potential.Because of the recent formation of this flora,I expected that a large proportion of the species may be alien and invasive.After compiling a comprehensive species list from previous research,I identified the taxonomic,life form,ecological,and geographical structures of the flora.The area belongs to the northern type of deserts with continental climate and low annual precipitation.Taxonomic and life form structures show that the flora is specific to Central Asian deserts.Ecological structure demonstrates a high percentage of halophytes,which resulted from their adaptation to soil salinity and shallow ground waters that occur throughout the study area.Geoelements of the flora indicate allochtonous properties of the flora （i.e.species derived from areas outside the study area） with a low proportion of native （Caspian） plants.Alien species are estimated to comprise 12％-19％ of the flora.Although some species have invasive features,severe arid environmental conditions and high salinity of soils and ground waters decrease invasive capacity of exotic plants.However,a threat of expansion of potentially invasive plants exists in the New Caspian marine plain due to the fast growth of anthropogenic habitats associated with recent oil developments.展开更多
The article summarizes 34 years (1980-2014) of the original observations of the genesis and evolution stages of the Caspian lagoons. A model of the formation and evolution of the coastal lagoons has been worked out. I...The article summarizes 34 years (1980-2014) of the original observations of the genesis and evolution stages of the Caspian lagoons. A model of the formation and evolution of the coastal lagoons has been worked out. It can be applied to the modelling of the global geoecological scenario along all the world’s coasts characterized by a steady transgression of their marine areas. The lagoons had been formed in a “bottleneck”, a narrow migration corridor, traversed by the largest migration route of trans-Palearctic species in Russia. This route is part of the West Siberian-East African migration range. Year round bird censuses (n = 746) were taken by the author in 1995-2014 along two key routes in the regions of Turalinskaya and Sulakskaya lagoons of Daghestan (the western coast of the Middle Caspian Sea). The meridional orientation of lagoons, location of the migration trajectory and a wide range of habitats in the study area contribute to the preservation of 294 Eurasian bird species. After formation of the lagoons, the breeding avifauna of the Caspian Sea Region of Central Daghestan has added 32 taxa. Among the species recorded at the lagoons, 50 are included in the IUCN Red List, Red Data Books of Russia and Daghestan. The reconstruction analysis of the migration trajectory compiled according to the data of the Russian Bird Ringing Centre allowed us to determine the population distribution geography for the birds regularly migrating along the western coast of the Caspian Sea and refine borders of theWest Siberian-East African migration range. Thus, according to the information received, the current migratory range should be greatly extended to cover the area from the British Isles in the West Palearctic to Lake Baikal in the east, including the extreme west and south of Africa.展开更多
Caspian clouds(CCs)are formed between the southern coast of the Caspian Sea and the Alborz Mountains.The purpose of this study is to identify characteristics of CCs using aerosol,cloud,and meteorological data from Mod...Caspian clouds(CCs)are formed between the southern coast of the Caspian Sea and the Alborz Mountains.The purpose of this study is to identify characteristics of CCs using aerosol,cloud,and meteorological data from ModernEra Retrospective analysis for Research and Applications version 2(MERRA-2),Moderate Resolution Imaging Spectroradiometer(MODIS),and ECMWF Reanalysis version 5(ERA5)during 2000–2020.During this period,we identified and investigated 636 days with CCs.The results indicated that the frequency(%)of these clouds was higher in the summer than in other seasons because synoptic system activity varies between hot and cold periods.The hot season with the beginning of high-pressure subtropical Azores activity and the formation of a stable atmosphere in northern Iran leads to more frequent occurrence of CCs.These clouds are mainly the low-and middle-level clouds in the region,e.g.,stratus and altocumulus.CCs resulted in 13.9%of annual rainfall,and 55.9%and 18.7%of the summer and autumn rainfall,respectively,relative to total rainfall from all cloud types in the study region.In the multivariate regression analysis,CC precipitation exhibited a strong positive relationship with the cloud water path(CWP),cloud optical thickness(COT),and cloud effective radius(CER).A comparison of the mean and standard deviation of aerosol optical thickness(AOT)and aerosol index(AI)for CC and non-CC days did not show a significant difference.Examination of the synoptic patterns showed that the main factors in the formation of CCs are the specific environmental conditions of the region and the orographic lift of stable air masses.The Hybrid Single-Particle Lagrangian Integrated Trajectory(HYSPLIT)model indicated that the source of moisture for the formation of CCs was largely the Caspian Sea.展开更多
根据渤海湾西岸有孔虫和介形虫与年代学(AMS14C和OSL测年)研究,将该段岩心自下而上划分为6个沉积单元(U1—U6),它们依次形成于晚更新世的河流及全新世的潮滩、浅海、前三角洲、三角洲前缘和三角洲平原沉积环境,结束于约35 ka的U1单元的...根据渤海湾西岸有孔虫和介形虫与年代学(AMS14C和OSL测年)研究,将该段岩心自下而上划分为6个沉积单元(U1—U6),它们依次形成于晚更新世的河流及全新世的潮滩、浅海、前三角洲、三角洲前缘和三角洲平原沉积环境,结束于约35 ka的U1单元的陆相环境,证实晚更新世低海面时渤海湾西岸未受海水影响。U1和U2单元之间,存在历时约27 ka的沉积间断(35～8.5 ka cal BP),研究区因此缺失早全新世沉积。U2单元的潮滩环境指示全新世海侵于8.5 ka cal BP到达渤海湾西岸,当时相对海平面为-16.7 m。U3单元为浅海环境,约6 ka cal BP时相对海平面上升到-6.8～-1.8 m。8.5～6 ka cal BP期间的海面上升速率是0.4～0.6 cm/a,可能与MWP1C事件有关。U4—U5单元,转为三角洲环境,沉积速率增大,反映自3.7 ka cal BP河流输入影响加强,约1.3 ka cal BP时成陆,形成U6单元。晚更新世35 ka以来的陆海环境演化,总体上是对气候变化控制下的海面变化的响应。展开更多
文摘The northeastern coast of the Caspian Sea is one of the youngest territories for plant colonization in Kazakhstan,and the flora of the most recent portion of this coastal area,the New Caspian marine plain,was chosen to study phytogeographical characteristics of plant species,especially as related to alien origin and invasive potential.Because of the recent formation of this flora,I expected that a large proportion of the species may be alien and invasive.After compiling a comprehensive species list from previous research,I identified the taxonomic,life form,ecological,and geographical structures of the flora.The area belongs to the northern type of deserts with continental climate and low annual precipitation.Taxonomic and life form structures show that the flora is specific to Central Asian deserts.Ecological structure demonstrates a high percentage of halophytes,which resulted from their adaptation to soil salinity and shallow ground waters that occur throughout the study area.Geoelements of the flora indicate allochtonous properties of the flora （i.e.species derived from areas outside the study area） with a low proportion of native （Caspian） plants.Alien species are estimated to comprise 12％-19％ of the flora.Although some species have invasive features,severe arid environmental conditions and high salinity of soils and ground waters decrease invasive capacity of exotic plants.However,a threat of expansion of potentially invasive plants exists in the New Caspian marine plain due to the fast growth of anthropogenic habitats associated with recent oil developments.
文摘The article summarizes 34 years (1980-2014) of the original observations of the genesis and evolution stages of the Caspian lagoons. A model of the formation and evolution of the coastal lagoons has been worked out. It can be applied to the modelling of the global geoecological scenario along all the world’s coasts characterized by a steady transgression of their marine areas. The lagoons had been formed in a “bottleneck”, a narrow migration corridor, traversed by the largest migration route of trans-Palearctic species in Russia. This route is part of the West Siberian-East African migration range. Year round bird censuses (n = 746) were taken by the author in 1995-2014 along two key routes in the regions of Turalinskaya and Sulakskaya lagoons of Daghestan (the western coast of the Middle Caspian Sea). The meridional orientation of lagoons, location of the migration trajectory and a wide range of habitats in the study area contribute to the preservation of 294 Eurasian bird species. After formation of the lagoons, the breeding avifauna of the Caspian Sea Region of Central Daghestan has added 32 taxa. Among the species recorded at the lagoons, 50 are included in the IUCN Red List, Red Data Books of Russia and Daghestan. The reconstruction analysis of the migration trajectory compiled according to the data of the Russian Bird Ringing Centre allowed us to determine the population distribution geography for the birds regularly migrating along the western coast of the Caspian Sea and refine borders of theWest Siberian-East African migration range. Thus, according to the information received, the current migratory range should be greatly extended to cover the area from the British Isles in the West Palearctic to Lake Baikal in the east, including the extreme west and south of Africa.
基金This work was supported by the Department of Climatology at the University of Tabriz.
文摘Caspian clouds(CCs)are formed between the southern coast of the Caspian Sea and the Alborz Mountains.The purpose of this study is to identify characteristics of CCs using aerosol,cloud,and meteorological data from ModernEra Retrospective analysis for Research and Applications version 2(MERRA-2),Moderate Resolution Imaging Spectroradiometer(MODIS),and ECMWF Reanalysis version 5(ERA5)during 2000–2020.During this period,we identified and investigated 636 days with CCs.The results indicated that the frequency(%)of these clouds was higher in the summer than in other seasons because synoptic system activity varies between hot and cold periods.The hot season with the beginning of high-pressure subtropical Azores activity and the formation of a stable atmosphere in northern Iran leads to more frequent occurrence of CCs.These clouds are mainly the low-and middle-level clouds in the region,e.g.,stratus and altocumulus.CCs resulted in 13.9%of annual rainfall,and 55.9%and 18.7%of the summer and autumn rainfall,respectively,relative to total rainfall from all cloud types in the study region.In the multivariate regression analysis,CC precipitation exhibited a strong positive relationship with the cloud water path(CWP),cloud optical thickness(COT),and cloud effective radius(CER).A comparison of the mean and standard deviation of aerosol optical thickness(AOT)and aerosol index(AI)for CC and non-CC days did not show a significant difference.Examination of the synoptic patterns showed that the main factors in the formation of CCs are the specific environmental conditions of the region and the orographic lift of stable air masses.The Hybrid Single-Particle Lagrangian Integrated Trajectory(HYSPLIT)model indicated that the source of moisture for the formation of CCs was largely the Caspian Sea.
文摘根据渤海湾西岸有孔虫和介形虫与年代学(AMS14C和OSL测年)研究,将该段岩心自下而上划分为6个沉积单元(U1—U6),它们依次形成于晚更新世的河流及全新世的潮滩、浅海、前三角洲、三角洲前缘和三角洲平原沉积环境,结束于约35 ka的U1单元的陆相环境,证实晚更新世低海面时渤海湾西岸未受海水影响。U1和U2单元之间,存在历时约27 ka的沉积间断(35～8.5 ka cal BP),研究区因此缺失早全新世沉积。U2单元的潮滩环境指示全新世海侵于8.5 ka cal BP到达渤海湾西岸,当时相对海平面为-16.7 m。U3单元为浅海环境,约6 ka cal BP时相对海平面上升到-6.8～-1.8 m。8.5～6 ka cal BP期间的海面上升速率是0.4～0.6 cm/a,可能与MWP1C事件有关。U4—U5单元,转为三角洲环境,沉积速率增大,反映自3.7 ka cal BP河流输入影响加强,约1.3 ka cal BP时成陆,形成U6单元。晚更新世35 ka以来的陆海环境演化,总体上是对气候变化控制下的海面变化的响应。
