Эколого-биологические аспекты кустарниковой мелиорации деградированных пастбищ на бугристо-увалистых комплексах песчаных земель Прикаспия

Abstract

The article presents the results of studies of the effectiveness of shrub reclamation on pastures of the Caspian Sea. Introduction. As a result of the outbreak of deflationary desertification of lands that occurred on the territory of the Russian Caspian Sea in the 70-80-ies of the XX century, it became necessary to develop methods for large-scale shrub reclamation of degraded lands. One of the problematic areas where these works were carried out is pastures on light soils of the Astrakhan Volga region. Materials and methods. The study is based on biomonitoring materials and field experiments using standard methods of forest taxation, soil science and geo-botany. Results and discussion. Thanks to the microclimate, the best conditions for the growth of herbaceous vegetation are formed in the spaces between pasture-protective strips with a width of 30 m. The yield of herbage phyto mass on them, both in spring and autumn, is higher by 0.06–0.13 t/ha. With severe damage or destruction of shrub plantations, areas with productive herbage degrade. Reclamation and forage plantations, depending on the age, increase the yield of pastures by 41–85%. The productivity of herbage is everywhere higher on pastures with a complex of pasture-protective and reclamation-forage plantations with teresken at the age of 20-25 years. Сonclusion. It has been established that pasture protection strips from haloxylon, reclamation and fodder plantations from krascheninnikovia and calligonum in the Astrakhan Volga region have been functioning for more than 45 years. It was determined that in forested areas, depending on age, the preservation of saxaul is 14–45% with an average plant height of 2.0–3.2 m. It is shown that the plantings of krascheninnikovia and calligonum on hollow-bumpy and withered plains with light soils at the age of 30–40 years have a safety of 45–70%, have a positive effect on the restorative succession of herbage between rows of shrubs and in the wind-shade zones of strip and backstage plantings. It was revealed that the addition to the pasture forage in the form of an available twig-leaf mass of shrubs in May – August can reach 0.5–4.0 t/ha in dry form. The hay yield of natural forage vegetation under the protection of shrub plantations on improved pastures is 1.2–1.5 times higher compared to unprotected lands and amounts to 0.70–1.60 t/ha. The results of the research can be useful in the phyto-melioration of degraded pastures located on bumpy sandy lands. Suggestions for practical application and direction of future research. The results of the research can be useful in the phytomelioration of degraded pastures located on bumpy sandy lands. An urgent problem remains the development of a system of measures for the care, repair and reconstruction of shrub plantations that can increase their productivity and durability on functioning pastures.