编号 2 (2024)

Hazardous weather events, which are increasing in frequency with global climate change, pose a threat to forest ecosystems over large areas. Heavy and destructive icy rain occurred in the south of Primorye on November 19, 2020. As a result of the breaking of branches and trunks on the territory of Russky Island, which is part of the Vladivostok urban district, 9.4 ± 1.7 m³/ha of dead fallen wood, which amounted to 4.8% of the total stock of stem wood, was produced. More than a third of all trees lost 50% of their crown. Specific losses of crown phytomass, calculated using regional allometric equations, are estimated at 12.2 ± 2.1 t/ha. The species that were most vulnerable to ice rain (Tilia amurensis and Betula dahurica) were represented by the largest trees, with a wide crown and a large proportion of branches in the total biomass. Lower canopy species (Carpinus cordata and Acer mono) were less affected. The share of the fallen stock of the forest stand (in relation to the total stock) was positively related to the height above sea level (R² = 0.54, p = 0.039), and the average diameter of the stand was significantly correlated with the phytomass of the fallen part of the crowns (R² = 0.51, p = 0.047). NDVI vegetation index values obtained from MODIS images for the 2020 and 2021 seasons (before and after the disturbance, respectively) differed significantly.

Pollution of water resources with pesticides negatively affects aquatic organisms and makes water bodies unsuitable for use by humans. Chemical analysis methods do not provide information about the impact of a detected substance and its individual components on the ecosystem. The article presents an analysis and synthesis of published data on the possibilities and features of the use of aquatic enzymes as biomarkers of pollution of aquatic ecosystems with pesticides. Publications over the past 20 years, indexed in the PubMed, Crossref, Web of Science, Scopus, and RSCI databases devoted to the issues of pesticide pollution of water bodies and the use of enzymes, in particular nonspecific esterases, in biomonitoring were analyzed. The concept of “biomarker” is revealed, groups of biomarkers, the purposes of their use, advantages and disadvantages as a source of information about the state of the ecosystem are listed. Particular attention is paid to study of nonspecific esterases in aquatic organisms (fish, mollusks, crustaceans, amphibians). The main types of substrates used to measure the activity of esterase isoforms and the features of changes in enzymatic activity in response to exposure to pesticides from different chemical groups (organophosphorus compounds, carbamates, pyrethroids) are considered. The factors influencing the activity of nonspecific esterases of aquatic organisms and limiting their use for assessing pollution of aquatic ecosystems are identified.

A new technique for assessing functional diversity is proposed, which is essentially a way to calculate Rao’s quadratic entropy. In contrast to the original method of calculating entropy, the new method takes into account intraspecific variability and allows us to evaluate other useful aspects of functional diversity, such as functional richness, functional evenness, the uniqueness of each species, and the contributions to functional diversity of intraspecific variability of each species and each trait separately. However, due to the peculiarities of the calculation, the proposed technique can only be applicable for an absolute count of all organisms within the “island” community or when collecting material based on a fixed sampling effort. The article provides an example of the application of the proposed technique to real rodent trapping data.

Enchytraeids are key organisms in the functioning of terrestrial ecosystems, but despite this, the fauna and population of enchytraeids of the European part of Russia (ER) have been studied rather poorly. Based on our own collections from 193 sites across the main biomes of the ER from 2019 to 2023, 74 species of enchytraeids belonging to 15 genera were identified. The presence of tundra, boreal, nemoral and desert faunal complexes of enchytraeids, as well as a group of polyzonal species, was shown. From a faunal perspective, the Caucasus, which is inhabited by a group of species that are not found anywhere else in Russia, stands out within the ER. Analysis of enchytraeid communities in various biomes of the ER at the species level will allow for a more correct assessment of their role in detrital food webs and the functioning of ecosystems overall.