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Tatyana М. Bragina and Dilyara D. Khisametdinova

Abstract

This paper presents first materials on the fauna and distribution of the terrestrial isopods - woodlice (Oniscidea) inhabiting the central and southern parts of Kostanay Region (Kazakhstan, Northern and Southern Turgai), located in the steppe zone. Most of the specimens of woodlice were collected in the territory of the National Nature Reserve “Altyn Dala”, a new protected area (established in 2012) and in the area of the Naurzum National Nature Reserve (established in 1931, World Heritage Site of UNESCO), on the Stipa lessingiana dry steppe. The list of woodlice includes six species (Crustacea: Isopoda: Oniscidea), belonging to five genera and three families in the study area. Four species are recorded for the first time in Kazakhstan - Desertoniscus subterraneus Verhoeff, 1930, Parcylisticus dentifrons (Budde-Lund 1885), Porcellio scaber Latreille, 1804, and Protracheoniscus major (Dollfus 1903). Distribution characteristics are provided for all of those species recorded in the study area. For the territory of Kazakhstan, according to a literature data, currently 16 species of terrestrial isopods have been recorded.

Open access

Michiel F. Bortier, Enrique Andivia, José G. Genon, Tine Grebenc and Gaby Deckmyn

Abstract

Many studies have shown the importance of ectomycorrhizal fungi (EM) in forests both for nutrient availability and for carbon (C) and nutrient cycling in the soil. Yet so far they are not incorporated in forest ecosystem growth and yield models. Recent research suggests phosphorus (P) shortage could be a major constraints to forest productivity in the future. For a realistic simulation of future forest ecosystem functioning, inclusion of detailed soil P cycling and the trees-EM interaction is necessary. We developed a full ecosystem P model that simulates P uptake by roots and EM, allocation within trees, physiological deficiency effects on C assimilation and allocation, release through litter decomposition, coupled with water, C and nitrogen (N) fluxes accounted for in the mechanistic forest stand model ANAFORE. Our results confirm the importance of incorporating EM in forest ecosystem models and suggest that the lack of incorporation of P in models may result in an under- or overestimation of forest growth. This new model has the potential of being used to assess the response of trees and/or stands to nutrient availability under different climate and management scenarios. With the current parameterization it is functional as a scientific research tool to investigate hypotheses.

Open access

Yakiv Didukh, Olga Chusova and Olga Demina

Abstract

The order Thymo cretacei-Hyssopetalia cretacei Didukh 1989 combines chalk outcrop plant communities of the southwestern Central Russian Upland. Its specificity can be attributed to a rather peculiar and heterogeneous flora with a large number of endemic species. The question about its origin has caused a lively discussion, which has been going on since the late nineteenth century. Since 1989 works on the classification of these communities have frequently been carried out, but until today no unanimous decision could be reached. The purpose of our research was to conduct a critical analysis of the syntaxonomical structure of Cretaceous outcrop vegetation and to show its difference from the steppe vegetation of the class Festuco-Brometea Br.-Bl. et Tx. ex Soó 1947. The territory of our research covers the southwestern foothills of the Central Russian Upland and the Donetsk Range, located only within the steppe zone and characterised by Cenomanian chalk outcrops. In total 354 relevés were used for the analysis. The modified TWINSPAN classification was used for the analysis. Our research has shown that the order Thymo cretacei-Hyssopetalia cretacei includes twelve associations belonging to three alliances: Artemisio hololeucae-Hyssopion cretacei Romashchenko et al. 1996, Euphorbio cretophilae-Thymion cretacei Didukh 1989 and Centaureo carbonatae-Koelerion talievii Romashchenko et al. 1996.

Open access

Katarína Pastirčáková, Helena Ivanová and Martin Pastirčák

Abstract

The diversity of fungi on branches and leaves of ashes (Fraxinus angustifolia, F. excelsior, F. ornus) in Slovakia was studied. Symptomatic material collected in Slovakia during the period of 2013 to 2017 and herbarium specimens previously collected were examined. In total, 30 fungal taxa (15 Deuteromycetes, 14 Ascomycetes and one Basidiomycetes) were recorded. Twenty-three of them have never been recorded on ashes in the country. The most frequently occurring fungi were Hymenoscyphus fraxineus (anamorph Chalara fraxinea) that causes necrosis of shoots and branches, and Phyllactinia fraxini, a foliar pathogen that causes powdery mildew disease. Fungal diversity on ashes growing in different types of stands was compared. Species richness was the greatest in seed orchards (20 fungal taxa) compared to private gardens, which contained the lowest (two fungal taxa). Species diversity in forest stands comprised 18 fungal taxa and the urban greenery was represented by 10 fungal taxa. Nine fungal taxa were recorded in tree alley along the road. The widest fungal species spectrum was recorded on F. excelsior.

Open access

V. F. Lima, S. V. Brito, J. A. Araujo Filho, D. A. Teles, S. C. Ribeiro, A. A. M. Teixeira, A. M. A. Pereira and W. O. Almeida

Summary

We tested the role of sex, size, and mass of the lizards Phyllopezus pollicaris, Gymnodactylus geckoides, Hemidactylus agrius, Lygodactylus klugei, and Hemidactylus brasilianus on the rates of pentastomid infection in the Brazilian Caatinga. We collected 355 individuals of these five species, of which four (prevalence of infection: P. pollicaris 15.9 %, G. geckoides 1.4 %, H. agrius 28.57 %, and H. brasilianus 4.16 %) were infected by Raillietiella mottae. Parasite abundance was influenced by host body size and mass only in P. pollicaris. Host sex did not influence the abundance of parasites in any species. Hemidactylus agrius, G. geckoides, and H. brasilianus are three new host records for pentastomids.

Open access

R. A. Aragón-Pech, H. A. Ruiz-Piña, R. I. Rodríguez-Vivas, A. D. Cuxim-Koyoc and E. Reyes-Novelo

Summary

Virginia opossum, Didelphis virginiana, is a synanthropic mammal associated with peridomestic areas of Yucatán, However, little is known about the gastrointestinal parasite infections of this species. The infection prevalence, mean abundance and mean intensity of eggs and oocysts of gastrointestinal parasites, in opossums captured in the peridomestic areas were estimated in six rural localities of Yucatán, Mexico. Eighty-four faecal samples were processed by flotation technique. McMaster test was used to estimate the number of helminth eggs and protozoa oocysts per gram of feces. Seven genera of gastrointestinal parasites were identified, and then infection prevalence was estimated as follows: Protozoa Eimeria sp. (51.9 %) and Sarcocystis sp. (1 %); nematodes Ancylostoma sp. (80.56 %), Cruzia sp. (62.04 %), Trichuris sp. (60.19 %), Capillaria sp. (29.63 %), Turgida sp. (23.15 %), Toxocara sp. (11.11 %), and Ascaris sp. (1.85 %); and one acanthocephalan: Oligacanthorhynchus sp. (14.81 %). This is the first study on the diversity of gastrointestinal parasites in Virginia opossums, and first evidence about the potential role of opossums in the transmission of zoonotic gastrointestinal parasites in peridomestic areas of Yucatán, Mexico.

Open access

S. G. Sokolov, F. K. Khasanov and I. I. Gordeev

Summary

The trematode Postlepidapedon opisthobifurcatum (Zdzitowiecki, 1990) is a common intestinal parasite of the gadiform fishes of the Southern Ocean. In this work, we supplement the description of the species with the anatomy of the terminal part of the reproductive system and with molecular data. The male terminal genitalia are characterised by the presence of the external seminal vesicle and cirrus-sac. The external seminal vesicle is surrounded by aciniform groups of outer prostatic cells. Groups of outer prostatic cells and proximal parts of their ducts are associated with a thin-walled membrane that is connected to the proximal edge of the cirrus-sac. The cirrus-sac is claviform, with a long proximal part accommodating the tubular, thin-walled internal seminal vesicle and ducts of outer prostatic cells. The female terminal genitalia are represented by a thick-walled metraterm, which is surrounded by aciniform groups of glandular cells. Phylogenetic analysis based on 28S rDNA partial sequences data placed P. opisthobifurcatum into the monophyletic group Lepidapedidae, including the species Myzoxenus insolens (Crowcroft, 1945), Intusatrium robustum Durio et Manter, 1968, and Postlepidapedon uberis Bray, Cribb et Barker, 1997. However, we were unable to detect direct phylogenetic connections between P. opisthobifurcatum and P. uberis.

Open access

Raisa Gracheva, Elena Belonovskaya and Vera Vinogradova

Abstract

Terraces represent one of the most common agricultural landscape elements in the mountainous regions of the North Caucasus. In the Central and West Caucasus, most of the arable terraces were converted into grasslands for grazing and haymaking 60-70 years ago and then abandoned or underused during the last 20-25 years. The role of abandoned terraces in maintaining the diversity of grasslands of the mountain slopes was studied in the case of eight terraces of different types. Plant communities of subalpine meadows and meadow steppes were distinguished on the terraces depending mainly on slope steepness at the same altitudes and to a lesser extent on the slope aspect. In general, the grasslands of the terrace platforms and those of original unterraced slopes had similar traits. At that, the mesophilous communities on the rich soils of terrace edges and scarp communities similar to vegetation of steep slopes with eroded soils create regular patterns on the terraced slopes. Thus, former agricultural terraces conditioning geodiversity also contribute to the diversity of plant communities and landscape fragmentation. The current increase of temperature and humidity may lead to a reduction of climatic differences of the slopes, and the further convergence of grassland communities can be assumed.

Open access

Sergiy Musienko, Volodymyr Luk’yanets, Oksana Tarnopylska, Oleksii Kobets and Vira Babenko

Abstract

The study was conducted in the forests of the State Enterprise “Gorodotske Forest Economy”, located in the Manevytsko-Volodymyretsky region of the Volyn Polissya in Ukraine. The annosum root rot (Heterobasidion annosum (Fr.) Bref.) impact on timber merchantability was investigated. The comparison of the cost estimation of stands assortment structure was carried out on the basis of the market value at current selling prices of the State Enterprise “Gorodotske Forest Economy” of the Volyn Regional Department of Forestry and Hunting as of 2017, taking into account the quality and the average length of the assortments. We present a comparative analysis of productivity, merchantability and assortment structure and financial value of timber volume by various assortments of pine and birch stands of the Volyn Polissya region affected by annosum root rot. We found that in the pine plantations, the overall productivity and the value of merchantable wood was higher by 42% in the control sites (areas between the fungal disease centers) as compared with those in the root rot disease centers. In the middle-aged birch-pine stands, the value of merchantable wood was higher than that in pine plantations of 34 the comparable age: by 9% in the disease centers and by 8% in control sites.