Abstract

Studies were carried out on four stationary transects laid in the Volga–Akhtuba floodplain by the Caspian expedition of Moscow State University in 1954—1955. The transects were reexamined in 1982 and in 2008–2013. The occurrence of the most common plant species in each of the three study periods was assessed. It was established that xerophytization and ruderalization of the flora occurred on all transects. The severity of these processes was not the same on different sections of the Volga–Akhtuba floodplain. They were most significant near the Volgograd hydroelectric power station and in places of valley narrowing. The main cause of vegetation xerophytization and ruderalization was the decrease in the height and duration of floods after regulation of the Volga flow, the high local pasture, and the recreational load. In the northern part of the floodplain, significant changes in the vegetation cover were made by invasions of adventitious species in natural phytocenoses: Fraxinus pennsylvanica, Bidens frondosa, Conyza canadensis, and Xanthium strumarium s. l.

中文翻译：

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伏尔加河流量调整后伏尔加-阿赫图巴洪泛区植物区系组成的变化

摘要

1954年至1955年，莫斯科国立大学里海考察队对伏尔加–阿赫图巴洪泛区铺设的四个静止样带进行了研究。分别在1982年和2008-2013年对这些样带进行了重新检查。评估了三个研究阶段中每个阶段最常见的植物物种的发生。已经确定，在所有样带上都发生了菌群的旱生和化。在伏尔加河至阿赫图巴河漫滩的不同区域，这些过程的严重性并不相同。它们在伏尔加格勒水电站附近和山谷变窄的地方最为重要。植被干旱化和粗化的主要原因是在调节伏尔加河流量，当地高草场和娱乐负荷之后，洪水的高度和持续时间的减少。宾夕法尼亚州的水曲柳，Bidens frondosa，加拿大的Conyza和Xanthium strumarium s。l 。