232 research outputs found
Biomass structure of Pinus sylvestris and Betula pendula forest ecosystems in pollution gradient near copper plant on the Southern Ural
In the gradient of pollution from the Karabash copper smelter in the Southern Urals (55 degrees 29' N, 60 degrees 13' E) in predominantly pure Scots pine and white birch stands, 12 and 34 sample plots are established, respectively, on which 42 and 56 model trees are taken, respectively, by stein diameter. The pollution gradient is expressed by the toxicity index suggested with a relative index of the content in the litter of three "technogenic" metals Cu, Ph and Fe. Regression analysis of the dependence of biomass and NPP of trees and stands from toxicity index is performed. There is a log-log-linear pattern of reduction of biomass and annual NIT of spruce-fir forest stands with increasing toxicity index in the direction to the source of pollution, but for the biomass of trees in the same gradient no consistent pattern is detected. The dry matter content (DMC) in all biomass components depends on the toxicity index and species at a statistically significant level: due to the increase in the toxicity index, it decreases in wood and bark, and increases in foliage and branches. At the same toxicity index, DMC in the branches and stem wood more in birch, but in the bark and foliage - in pine. In the wood and bark of a stem, this index is also related to the position in a stem: in the wood it decreases, and in the bark it increases in the direction from) the bottom up
Additive model of Larix sp. forest stand biomass sensitive to temperature and precipitation variables in Eurasia
The first attempt of modeling changes in additive component composition of biomass of Larix sp. communities on the Trans-Eurasian hydrothermal gradients based on regional peculiarities of age and morphology of the forests is attempted. The increase of all biomass components of the tree layer with increasing temperature at the constant precipitation and its decrease with increasing precipitation at the constant temperature is established. The positive relationship of the understory biomass with the temperature in the areas of insufficient moisture as the transition to moisture-rich areas is replaced by the opposite one. The development of such models for basic forest-forming species in Eurasia will give possibility to predict any changes in the biological productivity of forest cover of Eurasia in relation to climate change. © 2019 IOP Publishing Ltd. All rights reserved
Aboveground biomass of mongolian larch (Larix sibiricledeb.) forests in the eurasian region
We used our database of tree biomass with a number of 433 sample trees of Larix from different ecoregions of Eurasia, involving 61 trees from Mongolia for developing an additive model of biomass tree components. Our approach solved the combined problem of additivity and regionality of the model. Our additive model of tree aboveground biomass was harmonized in two ways: first, it eliminated the internal contradictions of the component and of the total biomass equations, secondly, it took into account regional (and correspondingly species-specific) differences of trees in its component structure. A significant excess of larch biomass in the forest-tundra is found that may be explained by permafrost conditions, by tree growth in low-yielding stands with a high basic density of stem wood and relatively high developed tree crown in open stands. The aboveground biomass of larch trees in Mongolia does not stand out against the background of the most ecoregions of Eurasia. Based on our results, we conclude that the growing conditions of larch in Mongolia are not as tough as it was suggested earlier by other scientists. Biomass relations between regions may be explained by unknown and unaccounted factors and errors of measurements in all their phases (assessment of age, diameter, height of a tree, the selection of supposedly representative samples of component biomass, their drying, weighing, etc.). The question what explains the regional differences in the structure of biomass of trees with the same linear dimensions of their stems, remains open. Undoubtedly, the differences in tree age here play an important role. Also, important factor is the variation in the morphological structure of stands, which, in turn, is determined by both climatic and edaphic factors. The obtained models allow the determination of larch forest biomass in different ecoregions of Eurasia with the help of height and diameter data. © 2019, Lomonosov Moscow State University. All rights reserved
Fir (Abies spp.) stand biomass additive model for Eurasia sensitive to winter temperature and annual precipitation
Climate change, especially modified courses of temperature and precipitation, has a significant impact on forest functioning and productivity. Moreover, some alterations in tree biomass allocation (e.g. root to shoot ratio, foliage to wood parts) might be expected in these changing ecological conditions. Therefore, we attempted to model fir stand biomass (t ha(-1)) along the trans-Eurasian hydrothermal gradients using the data from 272 forest stands. The model outputs suggested that all biomass components, except for the crown mass, change in a common pattern, but in different ratios. Specifically, in the range of mean January temperature and precipitation of -30 degrees C to +10 degrees C and 300 to 900 mm, fir stand biomass increases with both increasing temperature and precipitation. Under an assumed increase of January temperature by 1 degrees C, biomass of roots and of all components of the aboveground biomass of fir stands increased (under the assumption that the precipitation level did not change). Similarly, an assumed increase in precipitation by 100 mm resulted in the increased biomass of roots and of all aboveground components. We conclude that fir seems to be a perspective taxon from the point of its productive properties in the ongoing process of climate change.This paper was prepared within the programs of the current scientific research of the Ural Forest Engineering University and Botanical Garden of the Ural Branch of Russian Academy of Sciences. This work was supported by grant "EVA4.0", No. CZ.02.1.01/0.0/0.0/16_019/0000803 financed by OP RDE, by the Slovak Research and Development Agency under contracts No. APVV-15-0265, APVV-16-0325, APVV-18-0086 and the Scientific Grant Agency of the Ministry of Education, Science, Research and Sport of the Slovak Republic under contracts No. VEGA 1/0367/16
Фитомасса деревьев в лесах Евразии
A biomass data set of about 7000 model trees (more 70 % for Russia) for basic Eurasian forestforming species obtained on sample plots was compiled. Regression method, i.e. calculating regression dependencies of tree biomass on stem diameter, carried out by all thickness gradations in the forest stand, is currently generally accepted, and serve as the basis for determining the forest biomass per unit area. This is especially true for prevailing mixed forests in the forested lands, as estimating their biomass using ""areal"" database (Usoltsev, 2010) can result in significant biases. Even multifactor tree biomass equations calculated for a large and fairly representative original data sets for different regions do not qualify for global use due to discrepancies based on the data originating from different natural areas. The database is presented in English and Russian, it covers the territory of 22 states of Eurasia and consists of three sheets involving “Intro”, “Database” and “References”Сформирована сводка данных о фитомассе около 7000 модельных деревьев (из них более 70 % приходится на Россию) основных лесообразующих древесных пород Евразии, полученных на пробных площадях. Регрессионный метод – расчет регрессионных зависимостей фитомассы от диаметра ствола деревьев, взятых по всем ступеням толщины в древостое - в настоящее время является общепринятым, и на их основе определяется фитомасса насаждений на единице площади. Это особенно актуально для преобладающих в лесном фонде смешанных насаждений, определение фитомассы которых по «площадной» базе данных (Усольцев, 2010, 2013) может дать существенные смещения. Даже многофакторные модели подеревной фитомассы, рассчитанные по большим и достаточно репрезентативным исходным сводкам данных для разных регионов, не могут претендовать на всеобщее применение, из-за расхождений, обусловленных принадлежностью данных к разным природным зонам. Сформированная база данных представлена на английском и русском языках, охватывает территорию 22 стран Евразии и состоит из трех страниц: «Введение», «База данных» и «Литературные источники
Single-tree biomass data for remote sensing and ground measuring of Eurasian forests
This is CD-EXCEL enlarged version in English and Russian of single-tree biomass data set published in Russian in the monograph “Single-tree biomass of forest-forming species in Eurasia: database, climate-related geography, weight tables. Yekaterinburg: Ural State Forest Engineering University. 2016. 336 pp.” by V. A. Usoltsev. This database involves at the moment the data of dry biomass in kg (stems, bark, branches, foliage, roots), as well as of traditional taxation indices of more than 7330 trees of 30 Eurasian wood and brush species, measured on sample plots. This database covers the territory of 22 states of Eurasia. It consists of three pages involving “Intro”, “Database” and “References”
Geographic gradients of forest biomass of two needled pines on the territory of Eurasia
On the basis of the compiled database in a number of 3020 sample plots with determinations of forest biomass of two-needled pines (subgenus Pinus) on the territory of Eurasia from Great Britain to southern China and Japan statistically significant transcontinental gradients of stem, roots, aboveground and total biomass are established. In the direction from North to South these biomass components change according to a bell-shaped curvewith a maximum in the third (the southern temperate) zonal belt, while the biomass of needles, branches and understory is monotonically increasing within this zonal gradient from subarctic to subequato-rial zonal belts. In the direction from the Atlantic and Pacific coasts to the continentality pole in Siberia there is a biomass decrease as of all components of the wood story and the understory. The root: shoot ratio increases in the range between subarctic and southern temperate zone from 12 to 22% and then decreases to 16% in the subtropical zone, and within the southern temperate zone it monotonically increases from 20% on the oceanic coasts to 23% near continentality pole. The ratio of understory biomass to wood story biomass reduced from 4.0 to 2.5% ranging from subarctic to southern temperate zone and then rises to 3.5% in the subtropical zone, and within the south temperate zone it monotonically decreasing from the maximum value of 22% near Atlantic and Pacific coasts, approaching the level of 2-3% near the continentality pole. The results can be useful in the management of biosphere functions of forests undoubtedly. © 2018 Nicolaus Copernicus University. All rights reserved
Additive allometric models of single-tree biomass of Betula Sp. as a basis of regional taxation standards for Eurasia
In recent years, as the ecological role of forests has grown to a global level, the need to analyze their biological productivity in terms of biogeography has increased. Such studies are carried out mainly on a regional scale at the levels of both single-trees and forest stands. Thanks to formed by the authors the database on the biomass of 1076 sample trees of the genus Betula sp. growing on the territory of Eurasia, the trans-Eurasian model of tree biomass is proposed for the first time. The model takes into account regional differences in the biomass structure of equal-sized trees, harmonized on the principle of additivity. © 2018 Vladimir Andreevich Usoltsev et al., published by Sciendo
Comparing of allometric models of single-tree biomass intended for airborne laser sensing and terrestrial taxation of carbon pool in the forests of Eurasia
For the main tree species in North America, Europe, and Japan, a number of thousands of allometric equations for single-tree biomass estimation using mostly tree height and stem diameter at breast height are designed. An innovative airborne laser method of the forest canopy sensing allows to process online a number of morphological indices of trees, to combine them with the biomass allometric models, and to evaluate the forest carbon pools. The database of 28wood and shrub species containing 2.4 thousand of definitions is compiled for the first time in the forests of Eurasia, and on its basis the allometric transcontinental models of fractional structure of biomass of two types and dual use are developed. The first of them include as regressors the tree height and crown diameter and are intended for airborne laser location, whereas the latter have a traditional appointment for terrestrial forest biomass taxation using tree height and stem diameter. It is found that the explanatory capacity of the first model in comparison with the second one for foliage, branches, and roots is lower, but this difference is not statistically significant. The same capacity for the stem and aboveground biomass is lower too but this difference is statistically significant. Both models are designed for two different methods of taxation and cannot replace one another. Summary for Managers • We develop an innovative airborne laser method of the forest canopy sensing to evaluate the forest carbon pools. • We show this approach is highly reliable: in the most cases, there is more than 90% of tree biomass variability. • Processing speed of laser location, incommensurable with the terrestrial mensuration, gives the possibility to assess the change of carbon pool of forests on some territory during its periodic overflights. • The proposed information can be useful when implementing activities on climate stabilization, as well as in the validation of the simulation results when evaluating the carbon depositing capacity of forests. © 2018 Wiley Periodicals, Inc
Additive allometric model of Quercus spp. stand biomass for Eurasia
When using the unique in terms of the volume of database on the level of stand of the genus Quercus, the trans-Eurasian additive allometric models of biomass of stands for Eurasian Quercus forests are developed for the first time, and thereby the combined problem of model additivity and generality is solved. The additive model of forest biomass of Quercus is harmonized in two ways: it eliminated the internal contradictions of the component and the total biomass equations, and in addition, it takes into account regional differences of forest stands not only on total, aboveground and underground biomass, but also on its component structure, i.e. it reflects the regional peculiarities of the component structure of biomass
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