The Experts below are selected from a list of 162 Experts worldwide ranked by ideXlab platform
N G Moskalenko - One of the best experts on this subject based on the ideXlab platform.
-
Temperature Regimes of northern taiga Soils in the isolated permafrost zone of Western Siberia
Eurasian Soil Science, 2015Co-Authors: O. Yu. Goncharova, N G Moskalenko, G. V. Matyshak, A. A. Bobrik, O. E. PonomarevaAbstract:Soil Temperature Regimes were studied in three ecosystems of the north of Western Siberia in the zone of isolated permafrost: the forest ecosystem with gleyic loamy sandy podzol (Stagnic Albic Podzol), the flat-topped peat mound ecosystem with humus-impregnated loamy sandy to light loamy peat cryozem (Histic Oxyaquic Turbic Cryosol (Arenic)), and the peat mound (palsa) ecosystem with oligotrophic destructive permafrost-affected peat Soil (Cryic Histosol). Annual Temperature measurements in the Soil profiles demonstrated that these Soils function under different Temperature Regimes: very cold permafrost regime and cold nonpermafrost regime. The following annual Temperature characteristics proved to be informative for the studied Soils: sums of above-zero Temperatures at the depths of 10 and 20 cm, the maximum depth of penetration of Temperatures above 10°C, and the number of days with daily Soil Temperatures above (or below) 0°C at the depth of 20 cm. On the studied territory, the insulating effect of the snow cover in winter was at least two times more pronounced than the insulating effect of the vegetation cover in summer. Cryogenic Soils of the studied region are characterized by the high buffering towards changing climatic parameters. This is explained by the presence of the litter and peat horizons with a very low thermal diffusivity and by the presence of permafrost at a relatively shallow depth with Temperature gradients preventing penetration of heat to the permafrost table.
-
the thermal regime of Soils in the north of western siberia
Permafrost and Periglacial Processes, 2002Co-Authors: A. V. Pavlov, N G MoskalenkoAbstract:The results of long-term stationary observations upon the thermal regime of Soils in natural and anthropogenically-disturbed tundra and northern taiga landscapes in the north of Western Siberia are discussed. Quantitative assessments of the heating effect of snow cover and the cooling effect of surface organic layer on Soil Temperatures in both winter and summer seasons are given. Spatial and temporal variations in the depth of seasonal thaw and Soil Temperatures in the tundra and taiga zones are outlined. Data on changes in Soil Temperature Regimes following disturbance of surface organic layers are presented. Contemporary tendencies in permafrost degradation induced by climatic warming, changes in the snow cover depth, and anthropogenic impacts are shown. Copyright © 2002 John Wiley & Sons, Ltd.
Laiye Qu - One of the best experts on this subject based on the ideXlab platform.
-
root shoot communication of the seedlings of japanese larch and a hybrid species grown in different Soil Temperature Regimes
Landscape and Ecological Engineering, 2009Co-Authors: Laiye Qu, Satoshi Kitaoka, Kobayashi Makoto, M Kuromaru, M Osaki, Kaichiro Sasa, Hajime Utsugi, Takayoshi KoikeAbstract:We studied the effects of Soil Temperature (7, 15, and 25°C) on the growth and photosynthesis of seedlings of the Japanese larch (Larix kaempferi) and its hybrid larch (L. gmelinii × L. kaempferi) to simulate early stages of regeneration after disturbance. At a Soil Temperature of 7°C, the root length per unit root biomass, chlorophyll concentration, and photosynthetic nitrogen-use efficiency (PNUE) were markedly lower in the Japanese larch than in the hybrid larch, which may indicate that the hybrid larch is better at acquiring water and nutrients. At ambient Temperatures of 17–25°C, the light-saturated photosynthesis rate (P sat) of both seedlings grown at a Soil Temperature of 7°C was lower than at 15 or 25°C. By the 16th week, the needle area, root area, and biomass in seedlings of both types were lower at a Soil Temperature of 7°C than at Soil Temperatures of 15 or 25°C. At a Soil Temperature of 25°C, P sat and nitrogen uptake were lower in both larch species than at 15°C. The growth of the Japanese larch declined sharply from 15 to 25°C; however, the growth of the hybrid larch decreased only slightly from 15 to 25°C. We conclude that an increased Soil Temperature may retard larch growth in cold regions, especially in the case of the Japanese larch.
-
Root–shoot communication of the seedlings of Japanese larch and a hybrid species grown in different Soil-Temperature Regimes
Landscape and Ecological Engineering, 2009Co-Authors: Laiye Qu, Satoshi Kitaoka, Kobayashi Makoto, M Kuromaru, M Osaki, Kaichiro Sasa, Hajime Utsugi, Takayoshi KoikeAbstract:We studied the effects of Soil Temperature (7, 15, and 25°C) on the growth and photosynthesis of seedlings of the Japanese larch (Larix kaempferi) and its hybrid larch (L. gmelinii × L. kaempferi) to simulate early stages of regeneration after disturbance. At a Soil Temperature of 7°C, the root length per unit root biomass, chlorophyll concentration, and photosynthetic nitrogen-use efficiency (PNUE) were markedly lower in the Japanese larch than in the hybrid larch, which may indicate that the hybrid larch is better at acquiring water and nutrients. At ambient Temperatures of 17–25°C, the light-saturated photosynthesis rate (P sat) of both seedlings grown at a Soil Temperature of 7°C was lower than at 15 or 25°C. By the 16th week, the needle area, root area, and biomass in seedlings of both types were lower at a Soil Temperature of 7°C than at Soil Temperatures of 15 or 25°C. At a Soil Temperature of 25°C, P sat and nitrogen uptake were lower in both larch species than at 15°C. The growth of the Japanese larch declined sharply from 15 to 25°C; however, the growth of the hybrid larch decreased only slightly from 15 to 25°C. We conclude that an increased Soil Temperature may retard larch growth in cold regions, especially in the case of the Japanese larch.
Takayoshi Koike - One of the best experts on this subject based on the ideXlab platform.
-
root shoot communication of the seedlings of japanese larch and a hybrid species grown in different Soil Temperature Regimes
Landscape and Ecological Engineering, 2009Co-Authors: Laiye Qu, Satoshi Kitaoka, Kobayashi Makoto, M Kuromaru, M Osaki, Kaichiro Sasa, Hajime Utsugi, Takayoshi KoikeAbstract:We studied the effects of Soil Temperature (7, 15, and 25°C) on the growth and photosynthesis of seedlings of the Japanese larch (Larix kaempferi) and its hybrid larch (L. gmelinii × L. kaempferi) to simulate early stages of regeneration after disturbance. At a Soil Temperature of 7°C, the root length per unit root biomass, chlorophyll concentration, and photosynthetic nitrogen-use efficiency (PNUE) were markedly lower in the Japanese larch than in the hybrid larch, which may indicate that the hybrid larch is better at acquiring water and nutrients. At ambient Temperatures of 17–25°C, the light-saturated photosynthesis rate (P sat) of both seedlings grown at a Soil Temperature of 7°C was lower than at 15 or 25°C. By the 16th week, the needle area, root area, and biomass in seedlings of both types were lower at a Soil Temperature of 7°C than at Soil Temperatures of 15 or 25°C. At a Soil Temperature of 25°C, P sat and nitrogen uptake were lower in both larch species than at 15°C. The growth of the Japanese larch declined sharply from 15 to 25°C; however, the growth of the hybrid larch decreased only slightly from 15 to 25°C. We conclude that an increased Soil Temperature may retard larch growth in cold regions, especially in the case of the Japanese larch.
-
Root–shoot communication of the seedlings of Japanese larch and a hybrid species grown in different Soil-Temperature Regimes
Landscape and Ecological Engineering, 2009Co-Authors: Laiye Qu, Satoshi Kitaoka, Kobayashi Makoto, M Kuromaru, M Osaki, Kaichiro Sasa, Hajime Utsugi, Takayoshi KoikeAbstract:We studied the effects of Soil Temperature (7, 15, and 25°C) on the growth and photosynthesis of seedlings of the Japanese larch (Larix kaempferi) and its hybrid larch (L. gmelinii × L. kaempferi) to simulate early stages of regeneration after disturbance. At a Soil Temperature of 7°C, the root length per unit root biomass, chlorophyll concentration, and photosynthetic nitrogen-use efficiency (PNUE) were markedly lower in the Japanese larch than in the hybrid larch, which may indicate that the hybrid larch is better at acquiring water and nutrients. At ambient Temperatures of 17–25°C, the light-saturated photosynthesis rate (P sat) of both seedlings grown at a Soil Temperature of 7°C was lower than at 15 or 25°C. By the 16th week, the needle area, root area, and biomass in seedlings of both types were lower at a Soil Temperature of 7°C than at Soil Temperatures of 15 or 25°C. At a Soil Temperature of 25°C, P sat and nitrogen uptake were lower in both larch species than at 15°C. The growth of the Japanese larch declined sharply from 15 to 25°C; however, the growth of the hybrid larch decreased only slightly from 15 to 25°C. We conclude that an increased Soil Temperature may retard larch growth in cold regions, especially in the case of the Japanese larch.
A. V. Pavlov - One of the best experts on this subject based on the ideXlab platform.
-
the thermal regime of Soils in the north of western siberia
Permafrost and Periglacial Processes, 2002Co-Authors: A. V. Pavlov, N G MoskalenkoAbstract:The results of long-term stationary observations upon the thermal regime of Soils in natural and anthropogenically-disturbed tundra and northern taiga landscapes in the north of Western Siberia are discussed. Quantitative assessments of the heating effect of snow cover and the cooling effect of surface organic layer on Soil Temperatures in both winter and summer seasons are given. Spatial and temporal variations in the depth of seasonal thaw and Soil Temperatures in the tundra and taiga zones are outlined. Data on changes in Soil Temperature Regimes following disturbance of surface organic layers are presented. Contemporary tendencies in permafrost degradation induced by climatic warming, changes in the snow cover depth, and anthropogenic impacts are shown. Copyright © 2002 John Wiley & Sons, Ltd.
F. Stuart Chapin - One of the best experts on this subject based on the ideXlab platform.
-
response of eriophorum vaginatum to co2 enrichment at different Soil Temperatures effects on growth root respiration and po43 uptake kinetics
New Phytologist, 1996Co-Authors: Hormoz Bassirirad, David T. Tissue, James F Reynolds, F. Stuart ChapinAbstract:summary In a phytotron experiment, we examined responses of a tussock sedge, Eriophorum vaginatum L., to changes in atmospheric CO2, concentration and Soil Temperature. We were particularly interested in phosphorus (P) acquisition and below ground plant characteristics that regulated its uptake in response to CO2, enrichment. Plants were grown at two CO2, partial pressures, 35 and 70 Pa, three Soil Temperature Regimes, 5, 15 and 25 °C and a constant ambient air Temperature of 15 °C. Elevated CO2, increased total plant biomass production, but decreased tissue P concentration. Although high CO2, enhanced root carbohydrate concentration, it inhibited root respiration with no significant effect on root PO43− absorption capacity or root:shoot ratio. Surprisingly, there were no significant interactions between CO2, and Soil Temperature. The inability of Eriophorum to exhibit root–level compensatory adjustments, e.g. increased root: shoot ratio or PO43− absorption capacity, was largely responsible for the observed decline in tissue P concentration under elevated CO2, conditions. This could ultimately limit long–term growth responses of Eriophorum to CO2 enrichment in the field where P availability is limiting. We found that uptake of PO43− in response to elevated CO2 was independent of changes in root respiration, but changes in root respiration could have important implications for ecosystem carbon budget under elevated CO2 levels. Our data indicated that although root respiration on a per unit biomass basis declined in response to CO2 enrichment, this effect was counterbalanced by increased root biomass, so that high CO2 stimulated root respiration on a whole-plant basis by 30%. This might help to explain why long-term exposure to high CO2 increases CO2 efflux from Eriophorum-dominated ecosystems.