ЧОРНОЗЕМНІ ҐРУНТИ ОСТРОВА ЗМІЇНИЙ – ГЕОГРАФО- ГЕНЕТИЧНІ ОСОБЛИВОСТІ ТА ТЕНДЕНЦІЇ ЕВОЛЮЦІЇ

Abstract

В статті узагальнено й аналізуються результати багаторічного, починаючи з 2003-2005 рр., вивчення умов і процесів утворення та географо-генетичних особливостей чорноземних ґрунтів о. Зміїний. Встановлено тенденції сучасних процесів чорноземоутворення та вірогідні сценарії еволюційної зміни чорноземів острова. Обґрунтовано стратегію заходів щодо збереження унікального степового ландшафту острова з генетично-своєрідними чорноземними ґрунтами.

В статье обобщены и анализируются результаты многолетнего, начиная с 2003-2005 гг., изучения условий, процессов образования и географо-генетических особенностей черноземных почв о. Змеиный. Установлены тенденции современных процессов черноземообразования и вероятные сценарии эволюционного изменения черноземов острова. Обосновано стратегию мероприятий по сохранению уникального степного ландшафта острова с генетически своеобразными черноземными почвами.

Problem Statement and Purpose. Even the first researchers of the nature of the small (20.5 hectares) rocky Zmiiny Island in the northwestern Black Sea region visually diagnosed the soil there with black earth. However, the first special studies of the genetic nature of morphology, substance-chemical composition and properties of the chernozem soils of the island were conducted only from 2003-2005. The aim of the research is to establish geographic and genetic features of the soils of the island as a mirror of its specific natural and ecological conditions. Data & Methods. The materials cited in the article were obtained as a result of carrying out a considerable amount of field and laboratory-analytical work and research and mapping of soils of Zmiiny Island. Peculiarities of formation of chernozem soils on the island morphology, substance-chemical composition and properties and trends of modern change are analyzed using the methodological principles of the processgenetic paradigm and the results of many years of research. Results. Chernozem soils on the island are formed on a low-strength (25-40, up to 50 cm) rocky-gravelly crust of weathering of dense acidic rocks under the cover of almost virgin steppe herbaceous vegetation and year-round salting from the sea, mainly chlorides and Na sulfates. About 60-70% of the biomass of grasses is concentrated in the horizon of the ground turf Hd + on the ground layer of the steppe fume Ns, which can store a significant amount of atmospheric moisture. Surface runoff of surface water on areas with herbaceous vegetation is practically absent, therefore soil erosion is not manifested. The peculiarity of the process of black soil formation on the island is the increase in the capacity of the humus and accumulative horizon and the profile in general upwards direction as the bio-productivity of herbaceous vegetation increases. The chernozem soils, which were formed, are short-profile, gravel-stony, noncarbonate, practically non-structural, acidic, varyingly saline and solonettious, but without solonetso-iliuvial profile differentiation. The humus content in the upper horizons is very high (10-12, up to 15-18%), it is typical of the chernozem composition of the Chumic acid : Сfulvic acid (2,5-3,3), but with a sharp dominance of the fraction of HA-1 (70% and more) and very low content (1-2, up to 3-4%) or lack of typical chernozem fraction of HA-2. It is established that there is a tendency of irreversible constant increase of the chernozem properties and characteristics in soils – increase in the capacity of the humus and accumulative horizon and the profile in general, increase of the amount of absorbed cation-bases and reserves of humus and the content of the fraction of HA-2, decrease of acidity, increase of reserves of nutrition elements of plants. Two scenario of soil evolution is forecasted – ecologically optimistic provided the herbaceous vegetation is kept, and ecologically threatening at three sites of violation and contamination of the surface and destruction/erosion of the cover of herbal vegetation within the economic functional zone. We recommend to take measures for preservation of the unique steppe landscape of the island with genetically peculiar chernozem soils.