Natural and anthropogenic fragmentation of the birches in the forest-steppe zone of the Altai territory
Abstract
G.G. Sokolova, I.D. Borodulina
The article considers the results of the study of birch forests of forest-steppe zone of the Altai territory. The tendencies of anthropogenic changes in the species composition of birch forests are revealed. The process of fragmentation of birch pegs is analyzed, 3 levels of degradation are described. The synanthropization of birch forests occurs, accompanied by a decrease in their species and phytocenotic diversity. The consequences of synanthropization are the following: the fragmentation of plant populations and their isolation, the replacement of native plant communities by derivative and synanthropic, endemic and stenotopic plants by cosmopolitan and eurytopic ones, and the replacement of autochthonous elements by allochthonous ones. Universal impoverishment and unification of the species composition is accompanied by a decrease in productivity and resistance to external factors. Synanthropization causes leveling of zonal and regional differences of birch forests. As the anthropogenic load increases, the level of biodiversity decreases sharply, and during degradation, there is a transition to the dominance of species that are resistant to the changing ecotope conditions.
Monocenoses-homogeneous forest communities consisting only of forest species-are extremely rare in the study area. They are characterized by a high association between the stand and the stand, the homogeneity of the structure and the conjugation with the ecotope. These are reference sites with a complete absence of anthropogenic transformation. Most forest ecosystems are a subject to varying degrees of human pressure.
Keywords: Natural and anthropogenic fragmentation, island effect, birch forest
References:
Akatov, V. V. (2012). 60 let teorii dinamicheskogo ravnovesiya ostrovnoj biogeografii: problemy testirovaniya, rezul'taty polevykh issledovanij, prikladnoe znachenie. Zhurnal obshhej biologii. 73(3), 163-182 (in Russian).
Bierregaard, Jr. R. O., & Lovejoy, T. E. (1992). The biological dynamics of tropical rainforest fragments. Bioscience, 42(11), 859-866.
Bellegarde, A. L. (1971) Stepnoe lesovedenie. Moscow. Lesnaya promyshlennost (in Russian).
Brotons, L., Monkkonen, M., & Martin, J. L. (2003) Are fragments islands? Landscape context and density-area relationships in boreal forest birds. The American naturalist, 162(3), 343-357.
Burkey, T. V., & Reed, D. H. (2006). The effects of habitat fragmentation on extinction risk: mechanisms and synthesis. Songklanakarin Journal of Science and Technology, 28(1), 9-37.
Demina, O. N., Akatov, V. V., Sereda, M. M., Kondakova, M. Yu. (2006). Vliyanie izolyatsii na vidovoe bogatstvo stepnykh fitotsenozov gosudarstvennogo zapovednika “Rostovskij”. In: Rol' osobo okhranyaemykh prirodnykh territorij v sokhranenii bioraznoobraziya. Rostov na Dony. Rostov University Press, Russia. (in Russian)
Dombrovsky, Yu. A., & Tyutyunov, Yu. V. (1987). O svyazi vidovogo raznoobraziya s territorial'nymi razmerami izolyatov. Ehkologiya, 3, 3-7 (in Russian).
Helm, A., Hanski, I., Pärtel, M. (2006). Slow response of plant species richness to habitat loss and fragmentation. Ecology Letters, 9, 72-77.
Ibragimov, A. K., Petrova, A. N., Patova, M. A. (1999). Digressionno-vosstanovitel'nye suktsessii i dinamika bioraznoobraziya lesnykh ehkosistem. In: Ehkologicheskie problemy i puti ikh resheniya v zone srednego Povolzh'ya. Saransk. Sarans University Press (in Russian).
Ivanov, A. N. (2014). Problemy ostrovnogo landshaftovedeniya. In: Voprosy geografii. Moscow. Kodeks, pp. 138-158. (in Russian).
Kapos, V., Reynolds, G., Sinun, W. (2011). A large-scale forest fragmentation experiment: the stability of altered forest ecosystems project. Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences, 366(1582), 3292-3302.
Krauss, J., Klein, A. M., Dewenter, I. S., Tscharntke, T. (2004). Effects of habitat area, isolation, and landscape diversity on plant species richness of calcareous grasslands. Biodiversity and Conservation, 13, 1427-1439.
Lapshina E. I. (1963). Berezovye lesa lesostepi ehgo-vostoka Zapadnoj Sibiri (pp. 103-130). In: Rastitel'nost' stepnoj i lesostepnoj zona Zapadnoj Sibiri. Novosibirsk. Siberian Branch Academy of Sciences of the USSR (in Russian).
Laurance, W. F., Lovejoy, T. E., Vasconcelos, H. L., Bruna, E. M., Didham, R. K., Stouffer, Ph. C., Gascon, C., Bierregaard, R. O., Laurance, S. G., & Sampaio, E. (2002). Ecosystem decay of Amazonian forest fragments: a 22-year investigation. Conservation Biology, 16, 3, 605-618.
Malyshev, L. I. (1980). Izolirovannye okhranyaemye territorii kak lozhnoostrovnye bioty. ZHurnal obshhej biologii, 41(3), 338-349 (in Russian).
Martín-Queller, E., Albert, C. H., Dumas, P.-J., & Saatkamp, A. (2017). Islands, mainland, and terrestrial fragments: how isolation shapes plant diversity. Ecology and evolution, 7, 17, 6904-6917.
Resasco, J., Bruna, E. M., Haddad, N. M., Banks-Leite, C., Margules, C. R. (2017). The contribution of theory and experiments to conservation in fragmented landscapes. Ecography, 40(1), 109-118.
Simberloff, D. S., Abele, L. G. (1975). Island biogeography theory and conservation practica. Science, 191, 4-8.
Simberloff, D., Gotelli, N. (1984). Effects of insularisation on plant species richness in the prairie-forest ecotone. Conservation Biology, 29, 27-46.
Sokolova, G. G. (2013). Ostrovnoj effekt i ego vliyanie na berezovye kolki Аltajskogo kraya. Geografiya i prirodopol'zovanie Sibiri, 16, 178-187 (in Russian).
Sokolova, G. G. (2015). Vliyanie opakhivaniya na vidovoj sostav i strukturu berezovykh kolkov Аltajskogo kraya. Problemy botaniki Yuzhnoj Sibiri i Mongolii, 14, 225-227 (in Russian).
Wilcox, B. A. (1983). Ostrovnaya ekologiya i okhrana prirody (pp. 117-142). In: Biologiya okhrany prirody, Moscow (in Russian).
Watson, D. M. (2002). A conceptual framework for studying species composition in fragments, islands and other patchy ecosystems. Journal of Biogeography, 29(5-6), 823-834.