SUSTAINABILITY OF PEDOBIONT MEADOW COMMUNITIES UNDER ANTHROPOGENIC LOAD

Studies of the soil mesofauna were carried out in Tanaev meadows of the «Nizhnyaya Kama» National Park in natural and disturbed areas. The abundance of pedobionts and herpetobionts in natural areas significantly exceeded the abundance in disturbed areas. However, the taxonomic composition and trophic structure were similar. In general, communities structure indexes in natural sites indicate a stable ecosystem of floodplain meadows. The observance of pipe laying technology during further restoration of disturbed areas, high soil moisture and a small width of the disturbed soil layer contribute to the preservation and rapid restoration of the structure and population of large soil and litter invertebrates of meadow phytocenosis.

Influence of litter thickness on the structure of litter macrofauna of deciduous forests of Ukraine’s steppe zone

The litter in a forest ecosystem acts as a trophic substrate, and at the same time it is the environment for litter invertebrates. But despite this fact, there has been very little research conducted on the influence of litter thickness on the structure of litter macrofauna. The litter of steppe forests contains most types of integrated communities of forest ecosystems. This means that its thickness cannot avoid playing a significant role in the functioning of the ecosystem. Following to the standard methodologies, Invertebrates were collected using pit-fall traps in deciduous forests of Nikolaev, Zaporizhzhya, Dnipropetrovsk, Donetsk and Kharkiv oblasts, which are characterized by different types of geomorphological profile, different moisture conditions, soil salinity, tree crown and herbaceous vegetation density, soil texture and other factors. The total number of macrofauna increases in conditions where litter thickness exceeds40 mmin comparison with forest ecosystems with fragmented and average capacity litter. The number of litter macrofauna species also increases from 11–23 to 38 species on average when litter thickness increases to more than40 mm. The Shannon and Pielou diversity indexes show no definite tendencies to change in relation to changing degrees of litter thickness. At sites of greater thickness of the litter layer, the corresponding increase in the absolute number of litter mesofauna invertebrates is mostly due to saprophages, and the increase the number of species – due to zoophages. The optimum structure of domination was observed at sites with maximum thickness of litter. The proportion of large species shows no statistically significant change in relation to variations in litter thickness. The qualitative compound of the fauna at sites with thick litter changes mainly due to an increase in the number of Carabidae species.

Toads (Bufo bankorensis) influence litter chemistry but not litter invertebrates and litter decomposition rates in a subtropical forest of Taiwan

Few studies have been conducted to investigate ecological roles of litter amphibians in forest ecosystems. In this study, ten field enclosures (3 m × 2 m × 0.4 m) were used to evaluate effects of the toad Bufo bankorensis on the abundance of litter invertebrates (microbivores, fragmenters and predatory arthropods) and litter decomposition rates in a subtropical forest of southern Taiwan. Litterbags collected from toad and control (toad-excluded) enclosures were analysed for the communities and abundances of litter invertebrates and decay loss during this decomposition study from September to December 2001. The presence of B. bankorensis significantly changed phosphorus concentrations in the litter, but not the densities of litter invertebrates (microbivores, fragmenters and predatory arthropods) or rates of litter decomposition. These results were not consistent with previous studies, which have shown that Plethodon cenereus in a temperate forest of north-east USA and Eleutherodactylus coqui in a tropical rain forest of Puerto Rico significantly changed decomposition rates. We suggest that ecological roles of ground-dwelling amphibians may be species-specific and vary with different terrestrial ecosystems.