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Pablo L Peri - One of the best experts on this subject based on the ideXlab platform.
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carbon accumulation along a stand development sequence of nothofagus antarctica forests across a gradient in site quality in southern patagonia
Forest Ecology and Management, 2010Co-Authors: Pablo L Peri, Veronica Gargaglione, Guillermo Martinez Pastur, Maria Vanessa LencinasAbstract:Abstract Above- and below-ground C pools were measured in pure even-aged stands of Nothofagus antarctica (Forster f.) Oersted at different ages (5–220 years), crown and site classes in the Patagonian region. Mean tissue C concentRation varied from 46.3% in medium sized Roots of dominant trees to 56.1% in rotten wood for trees grown in low quality sites. Total C concentRation was in the order of: heartwood > rotten wood > sapwood > bark > small branches > coarse Roots > leaves > medium Roots > fine Roots. Sigmoid functions were fitted for total C accumulation and C Root/Shoot Ratio of individual trees against age. Total C accumulated by mature dominant trees was six times greater than suppressed trees in the same stands, and total C accumulated by mature dominant trees grown on the best site quality was doubled that of those on the lowest site quality. Crown classes and site quality also affected the moment of maximum C accumulation, e.g. dominant trees growing on the worse site quality sequestered 0.73 kg C tree−1 year−1 at 139 years compared to the best site where 1.44 kg C tree−1 year−1 at 116 years was sequestered. C Root/Shoot Ratio decreased over time from a maximum value of 1.3–2.2 at 5 years to a steady-state asymptote of 0.3–0.7 beyond 60 years of age depending on site quality. Thus, Root C accumulation was greater during the regeneRation phase and for trees growing on the poorest sites. The equations developed for individual trees have been used to estimate stand C accumulation from forest inventory data. Total stand C content ranged from 128.0 to 350.9 Mg C ha−1, where the soil C pool represented 52–73% of total ecosystem C depending on age and site quality. Proposed equations can be used for practical purposes such as estimating the impact of silvicultural practices (e.g. thinning or silvopastoral systems) on forest C storage or evaluating the development of both above- and below-ground C over the forest life cycle for different site qualities for accurate quantification of C pools at regional scale.
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dynamics of above and below ground biomass and nutrient accumulation in an age sequence of nothofagus antarctica forest of southern patagonia
Forest Ecology and Management, 2006Co-Authors: Pablo L Peri, Veronica Gargaglione, Guillermo Martinez PasturAbstract:Abstract Nothofagus antarctica (Forster f.) Oersted is a deciduous tree species, which naturally grows on poorly drained or drier eastern sites in the Andes Mountain near Patagonian steppe. Above- and below-ground biomass and nutrients pools were measured in pure even-aged stands at different ages (5–220 years) and crown classes. Functions were fitted for total biomass and nutrients accumulation, and Root/Shoot Ratio of individual trees against age. Total biomass accumulated for mature dominant trees was eight times greater than mature suppressed trees. Biomass Root/Shoot Ratio decreased with age from 1.8 to a steady-state of 0.5. All nutrients concentRation (except Ca) decreased with age and varied according to the degree of crown suppression classes. Nutrient concentRations varied between biomass pool components following the order leaves > bark > small branches > fine Roots > medium Roots > Rooten wood > coarse Roots > sapwood > heartwood. Total nutrient accumulation followed the order dominant > codominant > intermediate > suppressed trees and its accumulation rate varied over time, e.g. P accumulation rate of dominant trees increased from 0.17 g tree −1 year −1 during regeneRation to 1.39 g tree −1 year −1 in mature trees. Nutrients uptake reached a peak during the period of maximum biomass production, and Root/Shoot Ratio of nutrients decreased from its maximum value at 5 years of age (0.6, 4.0, 0.9, 1.5, 1.0 and 2.6 for N, P, K, Ca, S and Mg, respectively) to a steady-state asymptote beyond 50 years of age. Thus, accumulation of nutrients in Roots was greater during the regeneRation phase of stand development, and nutrient accumulation increased in above-ground over time. Also, nutrient use efficiency increased in mature trees (111–220 years) and decreased in suppressed crown classes. The equations developed for individual trees have been used to estimate stand biomass and nutrient accumulation from forest inventories data. Total stand biomass varied from 62.5 to 133.4 t ha −1 and total nutrients accumulation ranged from 3 kg Mg ha −1 to 1235 kg Ca ha −1 . Proposed equations can be used for practical purposes such as to estimate pasture nutrients requirement in a silvopastoral system based on nutrients supply from leaf litter returns, or to determine amelioRation practices like debarking stems before harvesting.
Guillermo Martinez Pastur - One of the best experts on this subject based on the ideXlab platform.
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carbon accumulation along a stand development sequence of nothofagus antarctica forests across a gradient in site quality in southern patagonia
Forest Ecology and Management, 2010Co-Authors: Pablo L Peri, Veronica Gargaglione, Guillermo Martinez Pastur, Maria Vanessa LencinasAbstract:Abstract Above- and below-ground C pools were measured in pure even-aged stands of Nothofagus antarctica (Forster f.) Oersted at different ages (5–220 years), crown and site classes in the Patagonian region. Mean tissue C concentRation varied from 46.3% in medium sized Roots of dominant trees to 56.1% in rotten wood for trees grown in low quality sites. Total C concentRation was in the order of: heartwood > rotten wood > sapwood > bark > small branches > coarse Roots > leaves > medium Roots > fine Roots. Sigmoid functions were fitted for total C accumulation and C Root/Shoot Ratio of individual trees against age. Total C accumulated by mature dominant trees was six times greater than suppressed trees in the same stands, and total C accumulated by mature dominant trees grown on the best site quality was doubled that of those on the lowest site quality. Crown classes and site quality also affected the moment of maximum C accumulation, e.g. dominant trees growing on the worse site quality sequestered 0.73 kg C tree−1 year−1 at 139 years compared to the best site where 1.44 kg C tree−1 year−1 at 116 years was sequestered. C Root/Shoot Ratio decreased over time from a maximum value of 1.3–2.2 at 5 years to a steady-state asymptote of 0.3–0.7 beyond 60 years of age depending on site quality. Thus, Root C accumulation was greater during the regeneRation phase and for trees growing on the poorest sites. The equations developed for individual trees have been used to estimate stand C accumulation from forest inventory data. Total stand C content ranged from 128.0 to 350.9 Mg C ha−1, where the soil C pool represented 52–73% of total ecosystem C depending on age and site quality. Proposed equations can be used for practical purposes such as estimating the impact of silvicultural practices (e.g. thinning or silvopastoral systems) on forest C storage or evaluating the development of both above- and below-ground C over the forest life cycle for different site qualities for accurate quantification of C pools at regional scale.
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dynamics of above and below ground biomass and nutrient accumulation in an age sequence of nothofagus antarctica forest of southern patagonia
Forest Ecology and Management, 2006Co-Authors: Pablo L Peri, Veronica Gargaglione, Guillermo Martinez PasturAbstract:Abstract Nothofagus antarctica (Forster f.) Oersted is a deciduous tree species, which naturally grows on poorly drained or drier eastern sites in the Andes Mountain near Patagonian steppe. Above- and below-ground biomass and nutrients pools were measured in pure even-aged stands at different ages (5–220 years) and crown classes. Functions were fitted for total biomass and nutrients accumulation, and Root/Shoot Ratio of individual trees against age. Total biomass accumulated for mature dominant trees was eight times greater than mature suppressed trees. Biomass Root/Shoot Ratio decreased with age from 1.8 to a steady-state of 0.5. All nutrients concentRation (except Ca) decreased with age and varied according to the degree of crown suppression classes. Nutrient concentRations varied between biomass pool components following the order leaves > bark > small branches > fine Roots > medium Roots > Rooten wood > coarse Roots > sapwood > heartwood. Total nutrient accumulation followed the order dominant > codominant > intermediate > suppressed trees and its accumulation rate varied over time, e.g. P accumulation rate of dominant trees increased from 0.17 g tree −1 year −1 during regeneRation to 1.39 g tree −1 year −1 in mature trees. Nutrients uptake reached a peak during the period of maximum biomass production, and Root/Shoot Ratio of nutrients decreased from its maximum value at 5 years of age (0.6, 4.0, 0.9, 1.5, 1.0 and 2.6 for N, P, K, Ca, S and Mg, respectively) to a steady-state asymptote beyond 50 years of age. Thus, accumulation of nutrients in Roots was greater during the regeneRation phase of stand development, and nutrient accumulation increased in above-ground over time. Also, nutrient use efficiency increased in mature trees (111–220 years) and decreased in suppressed crown classes. The equations developed for individual trees have been used to estimate stand biomass and nutrient accumulation from forest inventories data. Total stand biomass varied from 62.5 to 133.4 t ha −1 and total nutrients accumulation ranged from 3 kg Mg ha −1 to 1235 kg Ca ha −1 . Proposed equations can be used for practical purposes such as to estimate pasture nutrients requirement in a silvopastoral system based on nutrients supply from leaf litter returns, or to determine amelioRation practices like debarking stems before harvesting.
Anatoly S. Prokushkin - One of the best experts on this subject based on the ideXlab platform.
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Critical analysis of Root: Shoot Ratios in terrestrial biomes
Global Change Biology, 2006Co-Authors: Karel Mokany, R. Johnson Raison, Anatoly S. ProkushkinAbstract:One of the most common descriptors of the relationship between Root and Shoot biomass is the Root : Shoot Ratio, which has become a core method for estimating Root biomass from the more easily measured Shoot biomass. Previous reviews have examined Root : Shoot Ratio data, but have only considered particular vegetation types and have not always critically reviewed the data used. Reliable Root : Shoot Ratios are needed for a wide range of vegetation types in order to improve the accuracy of Root biomass estimates, including those required for estimating the effects of land management and land use change in National Greenhouse Gas Inventories. This study reviewed Root : Shoot Ratios in terrestrial biomes. A key facet of our analysis was a critical methodological review, through which unreliable data were identified and omitted on the basis of specific criteria. Of the 786 Root : Shoot Ratio observations collated, 62% were omitted because of inadequate or unverifiable Root sampling methods. When only the reliable data were examined, Root : Shoot Ratios were found to be negatively related to Shoot biomass, mean annual precipitation, mean annual temperature, forest stand age, and forest stand height. Although a single allometric equation derived in this study reliably predicted Root biomass from Shoot biomass for forests and woodlands, in general, the use of vegetation-specific Root : Shoot Ratios were found to be a more accurate method for predicting Root biomass. When the Root : Shoot Ratio data collated here were applied to an analysis of the global carbon budget, there was a 50% increase in estimated global Root carbon stock, and a 12% increase in estimated total carbon stock of terrestrial vegetation. The use of the vegetation-specific Root : Shoot Ratios presented in this study is likely to substantially improve the accuracy of Root biomass estimates for purposes such as carbon accounting and for studies of ecosystem dynamics.
Ranjan P. Ghimire - One of the best experts on this subject based on the ideXlab platform.
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Root biomass, Root/Shoot Ratio, and soil water content under perennial grasses with different nitrogen rates
Field Crops Research, 2017Co-Authors: Upendra M. Sainju, Brett L. Allen, Andrew W. Lenssen, Ranjan P. GhimireAbstract:Abstract Roots help in soil water and nutrient uptake and provide carbon (C) input for soil C sequestRation, but information on Root biomass of bioenergy perennial grasses is lacking. Root/Shoot Ratios are used to estimate crop Root biomass and C inputs, but the values for perennial grasses are also scanty. We examined Root biomass, Root/Shoot Ratios, and soil water contents to a depth of 120 cm after grass harvest in the fall for three bioenergy perennial grasses applied with four nitrogen (N) fertilization rates from 2011 to 2013 in the northern Great Plains, USA. Perennial grasses were intermediate wheatgrass (Thinopyrum intermedium [Host] Barkworth and Dewey), smooth bromegrass (Bromus inermis L.), and switchgrass (Panicum virgatum L.), and N fertilization rates were 0, 28, 56, and 84 kg N ha−1. Root biomass declined with depth and about 60% of the total biomass was located at 0–15 cm where intermediate wheatgrass and switchgrass had higher biomass than smooth bromegrass in 2011. Shoot biomass was greater in intermediate wheatgrass in 2011 and in switchgrass in 2013 than other grasses and increased with increased N rates. Root/Shoot Ratio was greater in switchgrass than other grasses at 0–120 cm in 2011, but was greater in smooth bromegrass than switchgrass at 0–60, 0–90, and 0–120 cm in 2012 and 2013. Mean Root/Shoot Ratios across N rates and years were not different among grasses and varied from 1.54 at 0–15 cm to 2.54 at 0–120 cm, which were substantially greater than 0.15 and 0.33, respectively, observed for spring wheat (Triticum aestivum L.). Soil water content increased with depth and was greater under switchgrass than other grasses at 0–120 cm in 2011 and 2013. Water content varied with N rate at various soil depths and years. Root biomass was negatively correlated with soil water content (r = −0.56, P = 0.03, n = 15). Because of greater Root and Shoot biomass, intermediate wheatgrass reduced soil water content due to increased water uptake and will likely provide more C inputs for soil C sequestRation from belowground biomass compared to smooth bromegrass and spring wheat.
Tomas Herben - One of the best experts on this subject based on the ideXlab platform.
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Root Shoot Ratio in developing seedlings how seedlings change their allocation in response to seed mass and ambient nutrient supply
Ecology and Evolution, 2018Co-Authors: Tereza Maskova, Tomas HerbenAbstract:: Root:Shoot (R:S) biomass partitioning is one of the keys to the plants' ability to compensate for limiting resources in the environment and thus to survive and succeed in competition. In adult plants, it can vary in response to many factors, such as nutrient availability in the soil or reserves in the Roots from the previous season. The question remains whether, at the interspecific level, reserves in seeds can affect seedlings' R:S Ratio in a similar way. Proper allocation to resource-acquiring organs is enormously important for seedlings and is likely to determine their survival and further success. Therefore, we investigated the effect of seed mass on seedling R:S biomass partitioning and its interaction with nutrient supply in the substrate. We measured seedling biomass partitioning under two different nutrient treatments after 2, 4, 6, and 12 weeks for seventeen species differing in seed mass and covering. We used phylogenetically informed analysis to determine the independent influence of seed mass on seedling biomass partitioning. We found consistently lower R:S Ratios in seedlings with higher seed mass. Expectedly, R:S was also lower with higher substrate nutrient supply, but substrate nutrient supply had a bigger effect on R:S Ratio for species with higher seed mass. These findings point to the importance of seed reserves for the usage of soil resources. Generally, R:S Ratio decreased over time and, similarly to the effect of substrate nutrients, R:S Ratio decreased faster for large-seeded species. We show that the seed mass determines the allocation patterns into new resource-acquiring organs during seedling development. Large-seeded species are more flexible in soil nutrient use. It is likely that faster development of Shoots provides large-seeded species with the key advantage in asymmetric above-ground competition, and that this could constitute one of the selective factors for optimum seed mass.
