Bredoire F.,French National Institute for Agricultural Research |
Nikitich P.,French National Institute for Agricultural Research |
Nikitich P.,Tomsk State University |
Barsukov P.A.,Institute of Soil science and Agrochemistry |
And 6 more authors.
Plant and Soil | Year: 2015
Aims: Forest-steppe and sub-taiga, two main biomes of southwestern Siberia, have been predicted to shift and spread northward with global change. However, ecological projections are still lacking a description of belowground processes in which fine roots play a significant role. We characterized regional fine root patterns in terms of length and mass comparing: 1) sites and 2) vegetation covers. Methods: We assessed fine root length and mass down to one meter in aspen (Populus tremula) and in grassland stands on six sites located in the forest-steppe and sub-taiga zones and presenting contrasting climate and soil conditions. We distinguished fine roots over diameter classes and also between aspen and understorey in forest. Vertical fine root exploration, fine root densities and total length and mass were computed for all species. Morphological parameters were computed for aspen. Results: In both forest and grassland, exploration was deeper and total length and mass were higher in forest-steppe than in sub-taiga. Exploration tended to be deeper in forest than in grassland and for trees than for understorey vegetation within forest stands. Conclusions: The differences in rooting strategies are related with both pedo-climatic conditions and vegetation cover. Further investigations on nutrient and water availability and on fine root dynamics should permit a better understanding of these patterns and help predicting their future with global changes. © 2015 Springer International Publishing Switzerland
Bredoire F.,French National Institute for Agricultural Research |
R Bakker M.,French National Institute for Agricultural Research |
Augusto L.,French National Institute for Agricultural Research |
A Barsukov P.,Institute of Soil science and Agrochemistry |
And 6 more authors.
Biogeosciences | Year: 2016
Climate change is particularly strong in northern Eurasia and substantial ecological changes are expected in this extensive region. The reshaping and migration northwards of bioclimatic zones may offer opportunities for agricultural development in western and central Siberia. However, the bioclimatic vegetation models currently employed for projections still do not consider soil fertility, in spite of this being highly critical for plant growth. In the present study, we surveyed the phosphorus (P) status in the south-west of Siberia where soils have developed on loess parent material. We selected six sites differing in pedoclimatic conditions and the soil was sampled at different depths down to 1ĝ€m in aspen (Populus tremula L.) forest as well as in grassland areas. The P status was assessed by conventional methods and by isotope dilution kinetics. We found that P concentrations and stocks, as well as their distribution through the soil profile, were fairly homogeneous on the regional scale studied, although there were some differences between sites (particularly in organic P). The young age of the soils, together with slow kinetics of soil formation processes have probably not yet resulted in a sufficiently wide range of soil physico-chemical conditions to observe a more diverging P status. The comparison of our data set with similar vegetation contexts on the global scale revealed that the soils of south-western Siberia, and more generally of northern Eurasia, often have (very) high levels of total, organic and inorganic P. The amount of plant-available P in topsoils, estimated by the isotopically exchangeable phosphate ions, was not particularly high but was intermediate on the global scale. However, large stocks of plant-available P are stored in subsurface layers which currently have low fine-root exploration intensities. These results suggest that the P resource is unlikely to constrain vegetation growth and agricultural development under the present conditions or in the near future. © Author(s) 2016. CC Attribution 3.0 License.
Stepanova V.A.,French National Center for Scientific Research |
Stepanova V.A.,Institute of Soil Science and Agrochemistry |
Pokrovsky O.S.,French National Center for Scientific Research |
Pokrovsky O.S.,Russian Academy of Sciences |
And 4 more authors.
Applied Geochemistry | Year: 2015
The concentrations of major and trace elements in the organic layer of peat soils across a 1800-km latitude profile of western Siberia were measured within various dominating ecosystems to evaluate the effect of landscape, latitude position and permafrost coverage on the peat chemical composition. In this study, peat core samples were collected every 10. cm along the entire length of the column, down to 3-4. m until the mineral horizon was reached. The peat samples were analyzed for major and trace elements using an ICP-MS technique following full acid digestion in a microwave oven. Depending on their concentration pattern along the peat column, several groups of elements were distinguished according to their general physico-chemical properties, mobility in soils, affinity to organic matter and plant biomass. Within similar ecosystems across various climate zones, there was a relatively weak variation in the TE concentration in the upper organic layer (green and brown parts of sphagnum mosses) with the latitude position. Within the intrinsic variability of the TE concentration over the peat column, the effects of climate, latitude position, and landscape location were not significantly pronounced. In different landscapes of the middle taiga, the peat columns collected in the fen zone, the low and mature forest, the ridge and the hollow did not demonstrate a statistically significant difference in most major and trace element concentrations over the full depth of the peat column. In live (green) parts and dead (brown) parts of sphagnum mosses from this climate zone, the concentrations of Mn, P, Ca and Cu decreased significantly with increasing moss net primary production (NPP) at various habitats, whereas the other elements exhibited no link with the NPP trends. The Al- and mineral horizon-normalized peat concentration profiles, allowing removal of the occasional contamination by the underlying mineral substrate and atmospheric dust, demonstrated a homogeneous distribution of TEs along the peat column among various climate zones in the non-permafrost regions but significantly non-conservative behavior in the discontinuous permafrost site. The peat deposits in the northern part of western Siberia potentially have very high release of metals to the surface waters and the riverine systems, depending on the persistence of the ongoing permafrost thaw and the increase in the thickness of the active layer. © 2014 Elsevier Ltd.
Strakhovenko V.D.,RAS Sobolev Institute of Mathematics |
Roslyakov N.A.,RAS Sobolev Institute of Mathematics |
Syso A.I.,Institute of Soil Science and Agrochemistry |
Ermolaeva N.I.,Russian Academy of Sciences |
And 3 more authors.
Water Resources | Year: 2016
Sapropels of lake systems in Novosibirsk oblast were studied to develop a scientific basis for their rational use. Sapropels from lakes in Novosibirsk oblast have been classified based on the ash content, chemical composition, and genesis. Organic–mineral and mineral–organic calcium and mixed sapropels of macrophyte and macrophyte–plankton genesis have been shown to be predominant by far among sapropel deposits in lakes in Novosibirsk oblast. © 2016, Pleiades Publishing, Ltd.
Ermakov N.,Central Siberian Botanical Garden |
Makhatkov I.,Institute of Soil Science and Agrochemistry
Plant Biosystems | Year: 2011
A classification of northern boreal light coniferous forests in the West Siberian plain has been developed using the Braun-Blanquet approach. In the northern part of the West-Siberian plain, boreal coniferous forests occur at the northern limit of their range characterized by a cold continental climate and the prevalence of long-frozen, poorly drained soils in watersheds. All syntaxa were assigned to the class Vaccinio-Piceetea Br.-Bl. in Br-Bl., Siss. & Vlieger 1939. Association Pinetum sibiricae-sylvestris Makhatkov et Ermakov 2010 has been included in the alliance Cladonio stellaris-Pinion sylvestris K.-Lund 1986, order Pinetalia sylvestris Oberd. 1957. Associations Melampyro pratense-Laricetum sibiricae ass. nova hoc loco and Ledo-Pinetum sibiricae ass. nova hoc loco have been included in the alliance Pino sibiricae-Laricion sibiricae Ermakov in Ermakov et Alsynbayev 2004 and the order Ledo palustris-Laricetalia cajanderi Ermakov in Ermakov et Alsynbayev 2004. Results of detrended correspondence analysis ordinations demonstrate a strong floristic integrity of the higher syntaxonomic units and clear syntaxonomic boundary between north boreal forests of the Vaccinio-Piceetea and swamp forests of the Oxycocco-Sphagnetea in spite of transitional floristic features in the majority of communities. © 2011 Copyright Taylor and Francis Group, LLC.