Role of Forest Shelterbelts in Conservation of Herpetofauna Biodiversity in the Steppe Dnieper Area

27 Mar Role of Forest Shelterbelts in Conservation of Herpetofauna Biodiversity in the Steppe Dnieper Area

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Abstract

Досліджено значення лісозахисних смуг у збереженні різноманіття амфібій та рептилій степового Придніпров’я в умовах інтенсивної сільськогосподарської діяльності. Виявлено, що герпетофауна штучних лісових насаджень правобережжя р. Самара, де зустрічаються зелена ропуха, землянка Палласа, прудка ящірка та мідянка звичайна, більш чисельніша та різноманітна на відміну від прилеглих агроценозів. У прилеглих до лісосмуг сільгоспугіддях формуються умови для існування лише двох видів герпетофауни: зеленої ропухи та прудкої ящірки.

English Abstract

The research was conducted in the spring and early summer of 2006, 2009 and 2011. We studied herpetofauna of agrocoenoses and the adjacent forest shelterbelts (Novomoskovs’k district of the Dnipropetrovsk region) (48.778° N, 35.429° E). Agrocoenoses are represented by sown areas with crop rotation of wheat Triticum L. and phacelia Phacelia Juss. Animal abundance was calculated as a number of individuals per 1 hectare. The studies have revealed that two amphibian species inhabit the forest shelterbelts, namely the green toad Bufotes viridis (Laurenti, 1768) and the Pallas spadefoot Pelobates vespertinus (Pallas, 1771) as well as two reptile species: the smooth snake Coronella austriaca Laurenti, 1768 and the sand lizard Lacerta agilis (Linnaeus, 1758). Only two species of them, L. agilis and B. viridis, were found in the agricultural fields. As would be expected, our studies have shown that the abundance of L. agilis in wood plantations was significantly higher than in adjacent agrocoenoses. The phytocoenosis has a significant impact on the characteristics of a lizard population, since it depends on the conditions of the basking and the forage limits. Obviously, that is the reason of low abundance of the lizards in the single-crop grassy agrocoenoses. In the steppe zone, C. austriaca inhabits forest ecosystems of flood plains and ravines. Due to adverse climatic and anthropogenic factors, there is a tendency for fragmentation and decrease of the C. austriaca populations. In the forest belts, this species has the lowest number among all the previously studied types of ecosystems, where it occurs in the steppe Dnieper area. According to our observations, the population density was not more than 0.5 spec/ha. Herpetofauna of forest shelterbelts is characterized by a large variety of the respective indices (H’ > 1; Is < 0.4) than on the crop areas (H' < 1; Is > 0.4). The statistically significant differences in the Shannon index (p < 0.01) between the forest belts and farm fields, which were observed each year, were revealed. In addition, the reptile and amphibian community in the forest belts has a lower degree of domination by the Berger–Parker index (D < 0.5) unlike agrocoenoses (D > 0.5). Thus, during the study period, the herpetofauna species composition of forest shelterbelts was 1.5–2 times higher than the species diversity of the agricultural fields. As this takes place, the animal abundance in shelterbelts 8.8–11.4 times higher than their number in agricultural fields. The amphibian and reptile community of the artificial forest plantations is more balanced and varied, but may be characterized by a lower species evenness due to the presence of several specimens of the rare species (C. austriaca). Agrocoenoses do not form proper living conditions for most herpetofauna species in the steppe zone of Ukraine. Taking into account the climate change processes, the artificial forest plantations form specific refugia with favourable microclimatic conditions.