ECOLOGICAL AND GEOCHEMICAL SPECIFICS OF SOIL AND PLANT COVERING OF URBAN LANDSCAPES (IN THE TOWN OF BROVARY AS AN EXAMPLE)

The results of the pollutants content research in urbanized landscapes soils of Ukraine (on the example of Brovary city, Kyiv region) were shown. The total and mobile contents data of chemical elements (Ni, Co, Zn, V, Pb, Cr, Cu) were obtained and analyzed using the methods of landscape-geochemical studies, analytical and statistical methods. The dependences of the vegetation resistance in cities to the level of soil cover contamination and the degree of heavy metals income have been established. The geochemical characteristics (such as the value of the accumulation coefficients; concentration of soil and vegetation cover; index of biogeochemical activity of the species within Brovary city) were analyzed. Throughout most of the city territory, the level of soil contamination is above average. Soils are characterized by the following association of heavy metals: Cu> Pb> Zn> Co> Cr> V> Mo> Mn> Ni. The dominant association is distributed heterogeneous throughout the city, forming geochemical anomalies depending on the source of contamination. The maximum technogenic load was recorded in urban soils areas within zones of transport infrastructure, production and communal-warehouse facilities.Woody vegetation is the most actively absorbed copper, manganese from the soil, and the least intensively absorbed chromium, vanadium and nickel. The biogeochemical activity coefficient of the research species is the following: Acer platanoides - 7,26, Betula pendula Roth. - 7,07, and Populus deltoides - 7,05, Pínus sylvestris - 1.32 and Alnus incana - 3.37. The biological absorption coefficients of manganese and copper are high because these metals have the ability to form strong complexes with organic matter. Biological absorption coefficients of vanadium and chromium is low for the researched plant species because these chemical elements are immobile in soils. For the city of Brovary, the presence of polyelemental contamination of soil and vegetation has been established. According to the indicators of the gross content of VM, the main pollutants are Cu, Zn, Pb and Mn. Concentrations of gross and mobile forms of VM exceed background values ​​and maximum concentration limits in 17-28 times. The maximum of man-caused load was recorded in the urban soils of the transport infrastructure zone and the zone of production and communal-warehouse facilities. Regularities of formation of elemental composition of plants of urban areas undergo significant changes in comparison with natural conditions, which is due to the strengthening of the role of foliar absorption of pollutants from the air and their high content in soils. The greatest ability to bioaccumulate has a male thyroid (Dryopteris filix-mas Schott) and birch (Convolvulus arvensis). The highest coefficient of biogeochemical activity of the studied species is Acer platanoides - 7.26, hanging birch (Betula pendula Roth.) - 7.07 and Canadian poplar (Populus deltoides) - 7.05, the lowest - Scots pine (Pínus sylvеstris ) - 1.32 and gray alder (Alnus incana) - 3.37. Weakly and very weakly, most of the studied plant species capture vanadium and chromium, which are relatively sedentary in the soil. Further research is needed to analyze the physicochemical parameters of soils, the coefficients of transition of metals to plants relative to their content in organic and mobile form in order to establish the relationships that characterize the process of translocation of chemical elements. Keywords: landscape-geochemical conditions, heavy metals, soils, vegetation.

Mind the gap: extending the conceptual model of river island development to different environmental conditions and tree species

<p>We present recent results of field observations on an island braided reach of the middle Tagliamento River, Italy, where riparian vegetation survival and establishment depends on an unstable balance between vegetation growth and flood disturbance. We combined field observations and information extracted from aerial images, airborne lidar data, and river flow time series for the period 1986-2017 to investigate the changing spatial distribution of woody vegetation and the associated changes in river topography. We also explored the role of Alnus incana (a member of the Betulaceae family), in an environment dominated by the Salicaceae family (e.g. Populus nigra).</p><p>We observed that gaps between established islands and/or floodplain offer shelter to vegetation, supporting higher colonisation success and different vegetation-landform evolution pathways.</p><p>In particular, A. incana predominantly grows in lines along channel, island and floodplain edges, bordering wooded areas dominated by P. nigra. Given their association with floodplain and island edges and the relationship of taller (older) trees with more elevated surfaces, A. incana in the study reach appears to complement the physical engineering of the dominant species, P. nigra. This suggests that P. nigra may facilitate colonisation by alder but then both species trap sediments to aggrade channel edges and bar surfaces and build island and floodplain landforms.</p><p>Time sequences of aerial images in combination with the flood disturbance time series allowed us to interpret vegetation dynamics and to identify the fate of sexual and asexual reproduction strategies by observing vegetation expansion from lines of young plants and shrubs and from uprooted deposited trees and pioneer islands, respectively. Field observations are then generalized to extend a conceptual model of island development.</p><p>Growing conditions, disturbance energy, and time (window of opportunity) between major floods are the main controls on vegetation colonization. These vary among rivers, among reaches along the same river and locally, as in the investigated gaps, allowing different tree species with different life history traits (e.g. Populus nigra, Alnus incana) to engineer local river landforms in different and complementary ways.</p><p>Although the conceptual model is inspired by observations on the Tagliamento River, consideration of species life history traits and the joint influences of growing conditions, disturbance energy and windows of opportunity provide a framework that may be applied to other temperate rivers where trees drive landform development.</p>

COMPARATIVE ANALYSIS OF SOME COMMODITY CHARACTERISTICS AND TECHNOLOGICAL PARAMETERS OF GRAY AND BLACK ALDER LEAVES

The article contains the results of studying a number of technological factors: bulk mass, bulk mass, specific gravity, porosity, free volume of the raw material layer, extractant absorption coefficients; as well as data on the analysis of some numerical quality indicators (humidity, total ash, ash insoluble in 10% solution of hydrochloric acid 10%) of gray and black alder (Alnus incana (L.) Moench и A. Glutinosa (L.) Gaerth ) leaves harvested in the middle zone of the Russian Federation. The obtained data are planned to be taken into account in the technological process of production of extraction preparations from the leaves of gray and black alder.

The Interactive Effect of Elevated CO2 and Herbivores on the Nitrogen-Fixing Plant Alnus incana ssp. rugosa

Many studies have found that future predicted CO2 levels can increase plant mass but dilute N content in leaves, impacting antiherbivore compounds. Nitrogen-fixing plants may balance their leaf C:N ratio under elevated CO2, counteracting this dilution effect. However, we know little of how plants respond to herbivores at the higher CO2 levels that occurred when nitrogen-fixing plants first evolved. We grew Alnus incana ssp. rugosa was grown at 400, 800, or 1600 ppm CO2 in soil collected from the field, inoculated with Frankia and exposed to herbivores (Orgyia leucostigma). Elevated CO2 increased nodulated plant biomass and stimulated the nitrogen fixation rate in the early growth stage. However, nitrogen-fixing plants were not able to balance their C:N ratio under elevated CO2 after growing for 19 weeks. When plants were grown at 400 and 1600 ppm CO2, herbivores preferred to feed on leaves of nodulated plants. At 800 ppm CO2, nodulated plants accumulated more total phenolic compounds in response to herbivore damage than plants in the non-Frankia and non-herbivore treatments. Our results suggest that plant leaf defence, not leaf nutritional content, is the dominant driver of herbivory and nitrogen-fixing plants have limited ability to balance C:N ratios at elevated CO2 in natural soil.

Сукцессионная динамика фитоценозов с участием полемохоров

В 2019–2020 гг. в Тверской области исследованы территории в окрестностях ключевых перевалочных пунктов Ржевско-Вяземского плацдарма. Изучены фитоценозы с участием полемохоров. Проанализированы сведения о динамике растительного покрова. После окончания Великой Отечественной войны на некоторых участках модельных территорий стали формироваться мелколиственные леса из Alnus incana (L.) Moench, Populus tremula L., Betula pendula Roth. и кустарниковые ивняки. Большинство полемохоров представляют группу луговых растений. На этих участках происходило постепенное выпадение полемохоров. Современный состав фитоценозов с полемохорами зависит от следующих факторов: 1) объема и состава занесенных чужеродных диаспор; 2) характера динамики ландшафтов и растительного покрова; 3) экологических особенностей отдельных видов. БлагодарностиРабота выполнена при финансовой поддержке гранта РФФИ № 18-04-01206. Авторы выражают глубокую благодарность А.В. Халиманчуку (Военно-исторический поисковый центр «Память 29 армии»), руководителю поискового отряда «Звезда» В.В. Стрельникову за ценные консультации и Е.А. Лубниной (ГБУЗ ГКБ им. М.П. Кончаловского ДЗМ) за помощь в организации исследований. Мы очень признательны С.Р. Майорову (Московский государственный университет им. М.В. Ломоносова) за проверку правильности определения гербарного материала.

Ecohydrological travel times derived from in situ stable water isotope measurements in trees during a semi–controlled pot experiment

Recent advances in in situ measurement techniques for stable water isotopes offer new opportunities to improve the understanding of tree water uptake processes and ecohydrological travel times. In our semi–controlled experiment with 20–year–old trees of three different species (Pinus pinea, Alnus incana and Quercus suber) placed in large pots, we applied in situ probes for stable water isotope measurements to monitor the isotopic signatures of soil water and tree xylem before and after two deuterium labelled irrigations. Additional destructive sampling of soil and plant material complemented the in situ measurements and allowed for a comparison between destructive (cryogenic vacuum extraction and direct water vapour equilibration) and in situ isotope measurements. For the first labelling pulse, the tracer based travel time at a stem height of 15 cm was 0.7 days for all three tree species but at 150 cm height tracer based travel times ranged between 2.4 (for Alnus incana) and 3.3 days (for Quercus suber). The tracer based travel time from the root zone to 15 cm stem height was similar to the sap flow based travel times (i. e., for all trees 0.7 days). However, sap flow based travel times were 1.3 days (for Alnus incana) longer than tracer based travel times at 150 cm stem height. In terms of different between tree species, we found similar tracer movement in Pinus pinea and Alnus incanca while in Quercus suber tracer travel times were longer which is likely due to lower water uptake rates of Quercus suber. The comparison of destructive and in situ isotope measurement techniques suggests notable differences in the sampled water pools. In situ measurements of soil and xylem water were much more consistent between the three tree pots (on average standard deviations were by 8.4 ‰ smaller for δ2H and by 1.6 ‰ for δ18O for the in situ measurements) but also among the measurements from the same tree pot in comparison to the destructive methods (on average standard deviations were by 7.8 ‰ and 1.6 ‰ smaller for δ2H and δ18O, respectively). Our study demonstrates the potential of semi-controlled large scale pot experiments and high-frequent in situ isotope measurements for monitoring tree water uptake and ecohydrological travel times. It also shows that differences in sampling techniques or sensor types need to be considered, when comparing results of different studies and within one study using different methods.

RIPARIAN AND SWAMP FORESTS AND SCRUB OF THE PINÉ PLATEAU (TRENTINO, NORTHERN ITALY)

The riparian and swamp forests/scrub of black alder (Alnus glutinosa), white alder (Alnus incana), grey willow (Salix cinerea) and bay willow (S. pentandra) of the Piné Plateau (Trentino, central Alps) are described here in terms of their floristic composition. They are assigned to the following associations: Filipendulo vulgarisAlnetum glutinosae, Stellario nemorum-Alnetum glutinosae, Carici elongatae-Alnetum glutinosae, Carici elataeAlnetum glutinosae, Frangulo-Salicetum cinereae and Salicetum pentandro-cinereae. In addition, information regarding the distribution of the previous woody communities in the Trentino-Alto Adige Region and their corresponding vegetation series and geosigmeta are provided.

The use of grey alder Alnus incana by foraging Black Woodpeckers Dryocopus martius during winter

Very few studies have been made on the Black Woodpecker’s Dryocopus martius feeding on deciduous trees in Scandinavia, especially at winter. This pilot study on the Black Woodpecker’s feeding in grey alder Alnus incana showed that the grey alder is a significant feeding tree during the winter months. The woodpeckers seem to prefer feeding in the southerly sector of grey alder trunks with a diameter of 13.5–15.4 centimetres, in their first dying stages. This study indicates that litter of a significant size, that is found beneath trees penetrated by woodpeckers, are from carvings made by the Black Woodpecker. Litter surveying may hence be an alternative investigational method to radio tracking for nutritional studies on the Black Woodpecker. This paper also discusses the role of a potential prey found in grey alders, the alder wood-wasp Xiphydria camelus, as a complementary food source at winter in different parts of Sweden, compared to the more well-described carpenter ants Camponotus herculeanus found in Norway spruce Picea abies.