Natural and anthropogenic factors influence on the botanic natural sanctuary vegetation cover dynamics of the river Volga delta

Federal state budget educational establishment of higher education «Astrakhan State University», Department of Ecology, Nature Management, Land Management and Life Safety, Astrakhan, 20а Tatischeva street, Russia

^* Corresponding author: m.v.valov@mail.ru

Abstract

The river Volga state assessment and landscape functioning is an extremely necessary part for stable and ecologically safe region development. One of the most important this assessment components is vegetation monitoring organization and conduction, which is the necessary part of modern ecosystem exploitation. Monitoring investigations brief results of the botanic natural monuments vegetation cover situated in the eastern part of the river Volga delta are shown in this work. Environment major factors change impact defining main ecological properties if deltoid landscape vegetation cover: some climatic characteristics, the river Volga hydrological regime changes and flooding conditions, vegetation cover differentiation peculiarities in dependence on deltoid land forms and confined processes to it are considered for the monitoring period. It was revealed during the monitoring that abrupt water-soluble salts amount increase in soils occurred, also toxicity level and soil salinization type from chloride- sulfate to sulfate-chloride, that affects vegetation cover: total biomass decrease, projective cover degree decrease on the all deltoid landscape high level, sedges and gramineous plant involvement degree decrease and herbs increase in vegetation cover due to ariditization degree and desert advancing caused either by natural or anthropogenic impact.