مقاله انگلیسی رایگان در مورد تاثیر گیاهان مصنوعی جنگلی بر خاک چمن زار – اسپرینگر 2018

On a global scale, the creation of artificial forest plantations on the initially forestless or deforested areas is regarded an important factor enhancing sequestration of carbon dioxide in different natural and climatic zones of the world [32, 35, 44, 50–52]. Estimates of the portion of carbon accumulated by the soil in forest plantations vary from less than 1% [47] to 39% [53]. Such a range of available estimates of the contribution of soils to the CO2 absorption is due to the strong dependence of the humus budget in forest ecosystems on a number of factors, including the initial humus content of the soil, the technology of its pre-planting preparation, the species composition and age of tree plantations, topography, climate, etc. [40, 43]. The most significant growth in the humus content of soils was observed during the forest planting or during natural overgrowing of abandoned arable lands with a low initial organic matter content [5, 38, 45, 46, 49, 50, 53]. At the same time, the planting of forests on pastures and in prairies led to some decrease in the storage of organic carbon and nitrogen in soils [39, 48]. Soil moistening also affects the dynamics of humus in soils under the forest. According to research in various regions of the world, a positive balance of humus is usually observed in the areas with precipitation of up to 800–1000 mm, and a negative balance of humus is observed in the areas with precipitation of more than 1000 mm [37, 38, 42, 49, 50]. Hence, forest planting may have a positive effect on the humus budget only for degraded soils of former agricultural lands under conditions of optimal moistening and the presence of grass cover in forest plantations. In addition to the impact on the dynamics of organic matter, forest planting significantly affects other soil indicators, including, in particular, the composition of the soil adsorption complex. A number of researchers note that an increase in acidity and a decrease in the amount of exchangeable bases are more expressed under coniferous species [33, 36, 39, 45, 46, 53]. The acidifying effect of forest plantations increases with an increase in the age of forest plantations and in the degree of their moistening [40]. Beginning from the early works by Korzhinsky [16], Tkachenko [29, 30], and Gorshenin [10], studies of the impact of artificial forest plantations on soil in the chernozemic zone have traditionally been focused on identification of the features of soil degradation. Numerous studies showed that the creation of forest plantations in the steppe and forest-steppe zones on plains with the hydrothermal coefficient of Selyaninov of 0.6–1.3 leads to certain changes in the properties of chernozems and dark chestnut soils. In particular, under the impact of woody vegetation, the crumb– granular structure is transformed into the angular blocky structure, the acidity of the soils increases, the humus content decreases, and the Cha/Cfa becomes smaller. Most scientists did not consider these changes as soil degradation [2, 3, 7, 20–22, 24] and emphasized the positive effect of forest vegetation on the original soil properties. The latter is manifested by an increase in the thickness of the humus horizon, an improvement of the soil physical and water-physical parameters, and leaching of soluble salts [3, 11, 13, 22, 23, 28, 31]. It was suggested that such soils should be referred to as forest-reclaimed chernozems [27].