The Experts below are selected from a list of 297 Experts worldwide ranked by ideXlab platform

Chuankuan Wang - One of the best experts on this subject based on the ideXlab platform.

  • Inter-specific and seasonal variations in photosynthetic capacity and water use efficiency of five temperate Tree species in Northeastern China
    Scandinavian Journal of Forest Research, 2010
    Co-Authors: Yunrong Sang, Chuankuan Wang, Hong Huo
    Abstract:

    Abstract Photosynthetic capacity (P max) and water use efficiency (WUE) are useful indices for describing CO2 uptake and H2O loss of Trees. Inter-specific and seasonal variations in P max and WUE of five Tree species were quantified in a Chinese temperate forest. The study included pioneer (white birch), mid-successional (Amur Cork-Tree, Manchurian walnut, Mongolian oak), and late-successional (Amur linden) species. The P max and WUE differed significantly among species, but the inter-specific variations were smaller than previously reported. Leaf-area-based P max varied from 5.1 for linden to 11.0 µmol m−2s−1 for birch, whereas leaf-mass-based P max ranged from 154 for linden to 252 µmol kg−1s−1 for walnut. Linden had the highest WUE, whereas walnut had the lowest. The seasonal patterns of P max and WUE were significantly different between species. The P max of birch increased as the season proceeded, whereas the P max of the other four species was lowest in May, and peaked in June. The seasonality of P ...

  • Heartwood and sapwood allometry of seven Chinese temperate Tree species
    Annals of Forest Science, 2010
    Co-Authors: Xingchang Wang, Quanzhi Zhang, Chuankuan Wang, Xiankuai Quan
    Abstract:

    • Allometry of sapwood/heartwood is essential for understanding Tree growth, water transport and carbon allocation, timber production and use, but such an allometry is lacking for Chinese temperate Tree species. • We studied the allometry and development of heartwood and sapwood for seven Chinese temperate Tree species: Korean pine (Pinus koraiensis Sieb. et Zucc), Dahurian larch (Larix gmelinii Rupr.), Japanese elm (Ulmus davidiana Planch var. japonica (Rehd.) Nakai), Manchurian ash (Fraxinus mandshurica Rupr.), Manchurian walnut (Juglans mandshurica Maxim.), Amur Cork-Tree (Phellodendron amurense Rupr.), and Mongolian oak (Quercus mongolica Fisch.). • All heartwood parameters investigated, including heartwood radius (HR), heartwood formation rate (HFR), heartwood ring number (HRN), heartwood initiation age (HIA), and heartwood volume ratio (HVR), were positively correlated with Tree cambial age (CA). The HR, sapwood width (SW), sapwood area (SA), heartwood and sapwood volumes were significantly related to stem diameter at breast height (DBH) or xylem diameter. There was a polynomial relationship between the sapwood ring longevity (SRL) and sapwood ring number (SRN). However, most of the allometric relationships were species-dependent. The hardwood formation patterns were different between coniferous and broadleaved Tree species. A power function was suitable to scale SA from DBH, but the exponent varied from 1.32 for the larch to 2.19 for the Cork-Tree. • Our allometry provided a practical means to assess wood development and related physiology for the temperate Tree species.

  • Carbon concentration variability of 10 Chinese temperate Tree species
    Forest Ecology and Management, 2009
    Co-Authors: Quanzhi Zhang, Xingchang Wang, Chuankuan Wang, Xiankui Quan
    Abstract:

    Abstract A mass-based carbon (C) concentration ([C]) of 50% in dry wood is widely accepted as a constant factor for conversion of biomass to C stock. However, the [C] varies with Tree species, and few data on [C] are available for the Chinese temperate Tree species. In this study, we examined inter- and intra-specific variations of [C] in biomass tissues for 10 co-occurring temperate Tree species in northeastern China. The species were Korean pine ( Pinus koraiensis Sieb. et Zucc.), Dahurian larch ( Larix gmelinii Rupr.), Mongolian oak ( Quercus mongolica Fisch.), white birch ( Betula platyphylla Suk.), Amur Cork-Tree ( Phellodendron amurense Rupr.), Manchurian walnut ( Juglans mandshurica Maxim.), Manchurian ash ( Fraxinus mandshurica Rupr.), aspen ( Populous davidiana Dode), Mono maple ( Acer mono Maxim.), and Amur linden ( Tilia amurensis Rupr.). The mean tissue [C] across the species varied from 47.1% in fine root to 51.4% in foliage. The mean stem [C] of the 10 species was 49.9 ± 1.3% (mean ± SE). The weighted mean C concentration (WMCC) for the species ranked as: Amur Cork-Tree (55.1%) > Amur linden (53.9%) > Korean pine (53.2%) > Manchurian ash (52.9%) > Manchurian walnut (52.4%) > Mongolian oak (47.6%) > Dahurian larch (46.9%) > Mono maple (46.4%) > white birch (46.1%) > aspen (43.7%). The WMCC of the dominant Trees was negatively correlated to mean annual increment of biomass (MAI), suggesting that planting fast-growing Tree species for C sequestration in afforestation and reforestation practices sacrifice some C gain from increasing MAI due to decreasing [C]. Failing to account for the inter- and intra-specific variations in [C] will introduce a relative error of −6.7% to +7.2% in estimates of biomass C stock from inventory data, of which >93% is attributed to ignoring the inter-specific variation in [C].

  • Biomass allometric equations for 10 co-occurring Tree species in Chinese temperate forests
    Forest Ecology and Management, 2006
    Co-Authors: Chuankuan Wang
    Abstract:

    Abstract The temperate forest in northeastern China accounts for more than one-third of Chinese forest resources (both area and stocking volume), and plays a key role in the national and global carbon budgets and climatic system. However, few allometric equations exist for accurately estimating biomass and carbon budgets of the forest. In this study, allometric equations were developed relating component biomass to diameter at breast height (DBH) and Tree height (H) to DBH for 10 co-occurring Tree species in the Chinese temperate mixed forest. The 10 species were Korean pine (Pinus koraiensis Sieb. et Zucc.), Dahurian larch (Larix gmelinii Rupr.), Mongolian oak (Quercus mongolica Fisch.), white birch (Betula platyphylla Suk.), Amur Cork-Tree (Phellodendron amurense Rupr.), Manchurian walnut (Juglans mandshurica Maxim.), Manchurian ash (Fraxinus mandshurica Rupr.), aspen (Populous davidiana Dode), maple (Acer mono Maxim.), and Amur linden (Tilia amurensis Rupr.). The biomass components included stem, current-year branch, older branch, current-year foliage, older foliage, stump, and coarse root (diameter ≥5 mm). Harvested Tree DBH ranged from 2.4 to 57.1 cm. Generalized biomass allometric equations that ignored Tree species, based on DBH and fitted on a log–log scale, explained more than 90% of variability in woody component biomass, but the species effect was significant (α = 0.05). Including Tree height as the second independent variable in the allometric equations improved the accuracy of biomass estimates, especially for foliage biomass. The relative differences in biomass estimated from the generalized, DBH-only, and DBH–H combined equations varied from −50.6% to 43.9% depending upon model form, species, and biomass component. Foliage biomass was more variable than other component biomass both across and within Tree species. Some potential sources of error in biomass estimation were also discussed.

M.a.v. Madeira - One of the best experts on this subject based on the ideXlab platform.

  • Influence of Tree canopy on N 2 fixation by pasture legumes and soil rhizobial abundance in Mediterranean oak woodlands
    Science of The Total Environment, 2014
    Co-Authors: C. Carranca, I.v. Castro, N. Figueiredo, R. Redondo, A.r.f. Rodrigues, I. Saraiva, R. Maricato, M.a.v. Madeira
    Abstract:

    Symbiotic N2 fixation is of primordial significance in sustainable agro-forestry management as it allows reducing the use of mineral N in the production of mixed stands and by protecting the soils from degradation. Thereby, on a 2-year basis, N2 fixation was evaluated in four oak woodlands under Mediterranean conditions using a split-plot design and three replicates. 15N technique was used for determination of N2 fixation rate. Variations in environmental conditions (temperature, rainfall, radiation) by the Cork Tree canopy as well as the age of stands and pasture management can cause great differences in vegetation growth, legume N2 fixation, and soil rhizobial abundance. In the present study, non-legumes dominated the swards, in particular beneath the Tree canopy, and legumes represented only 42% of total herbage. A 2-fold biomass reduction was observed in the oldest sown pasture in relation to the medium-age sward (6 t DW ha− 1 yr− 1). Overall, competition of pasture growth for light was negligible, but soil rhizobial abundance and symbiotic N2 fixation capacity were highly favored by this environmental factor in the spring and outside the influence of Tree canopy. Nitrogen derived from the atmosphere was moderate to high (54–72%) in unsown and sown swards. Inputs of fixed N2 increased from winter to spring due to more favorable climatic conditions (temperature and light intensity) for both rhizobia and vegetation growths. Assuming a constant fixation rate at each seasonal period, N2 fixation capacity increased from about 0.10 kg N ha− 1 per day in the autumn–winter period to 0.15 kg N ha− 1 per day in spring. Belowground plant material contributed to 11% of accumulated N in pasture legumes and was not affected by canopy. Size of soil fixing bacteria contributed little to explain pasture legumes N.

  • Influence of Tree canopy on N₂ fixation by pasture legumes and soil rhizobial abundance in Mediterranean oak woodlands.
    The Science of the total environment, 2014
    Co-Authors: C. Carranca, I.v. Castro, N. Figueiredo, R. Redondo, A.r.f. Rodrigues, I. Saraiva, R. Maricato, M.a.v. Madeira
    Abstract:

    Symbiotic N2 fixation is of primordial significance in sustainable agro-forestry management as it allows reducing the use of mineral N in the production of mixed stands and by protecting the soils from degradation. Thereby, on a 2-year basis, N2 fixation was evaluated in four oak woodlands under Mediterranean conditions using a split-plot design and three replicates. (15)N technique was used for determination of N2 fixation rate. Variations in environmental conditions (temperature, rainfall, radiation) by the Cork Tree canopy as well as the age of stands and pasture management can cause great differences in vegetation growth, legume N2 fixation, and soil rhizobial abundance. In the present study, non-legumes dominated the swards, in particular beneath the Tree canopy, and legumes represented only 42% of total herbage. A 2-fold biomass reduction was observed in the oldest sown pasture in relation to the medium-age sward (6 t DW ha(-1)yr(-1)). Overall, competition of pasture growth for light was negligible, but soil rhizobial abundance and symbiotic N2 fixation capacity were highly favored by this environmental factor in the spring and outside the influence of Tree canopy. Nitrogen derived from the atmosphere was moderate to high (54-72%) in unsown and sown swards. Inputs of fixed N2 increased from winter to spring due to more favorable climatic conditions (temperature and light intensity) for both rhizobia and vegetation growths. Assuming a constant fixation rate at each seasonal period, N2 fixation capacity increased from about 0.10 kg N ha(-1) per day in the autumn-winter period to 0.15 kg N ha(-1) per day in spring. Belowground plant material contributed to 11% of accumulated N in pasture legumes and was not affected by canopy. Size of soil fixing bacteria contributed little to explain pasture legumes N.

Xingchang Wang - One of the best experts on this subject based on the ideXlab platform.

  • Heartwood and sapwood allometry of seven Chinese temperate Tree species
    Annals of Forest Science, 2010
    Co-Authors: Xingchang Wang, Quanzhi Zhang, Chuankuan Wang, Xiankuai Quan
    Abstract:

    • Allometry of sapwood/heartwood is essential for understanding Tree growth, water transport and carbon allocation, timber production and use, but such an allometry is lacking for Chinese temperate Tree species. • We studied the allometry and development of heartwood and sapwood for seven Chinese temperate Tree species: Korean pine (Pinus koraiensis Sieb. et Zucc), Dahurian larch (Larix gmelinii Rupr.), Japanese elm (Ulmus davidiana Planch var. japonica (Rehd.) Nakai), Manchurian ash (Fraxinus mandshurica Rupr.), Manchurian walnut (Juglans mandshurica Maxim.), Amur Cork-Tree (Phellodendron amurense Rupr.), and Mongolian oak (Quercus mongolica Fisch.). • All heartwood parameters investigated, including heartwood radius (HR), heartwood formation rate (HFR), heartwood ring number (HRN), heartwood initiation age (HIA), and heartwood volume ratio (HVR), were positively correlated with Tree cambial age (CA). The HR, sapwood width (SW), sapwood area (SA), heartwood and sapwood volumes were significantly related to stem diameter at breast height (DBH) or xylem diameter. There was a polynomial relationship between the sapwood ring longevity (SRL) and sapwood ring number (SRN). However, most of the allometric relationships were species-dependent. The hardwood formation patterns were different between coniferous and broadleaved Tree species. A power function was suitable to scale SA from DBH, but the exponent varied from 1.32 for the larch to 2.19 for the Cork-Tree. • Our allometry provided a practical means to assess wood development and related physiology for the temperate Tree species.

  • Carbon concentration variability of 10 Chinese temperate Tree species
    Forest Ecology and Management, 2009
    Co-Authors: Quanzhi Zhang, Xingchang Wang, Chuankuan Wang, Xiankui Quan
    Abstract:

    Abstract A mass-based carbon (C) concentration ([C]) of 50% in dry wood is widely accepted as a constant factor for conversion of biomass to C stock. However, the [C] varies with Tree species, and few data on [C] are available for the Chinese temperate Tree species. In this study, we examined inter- and intra-specific variations of [C] in biomass tissues for 10 co-occurring temperate Tree species in northeastern China. The species were Korean pine ( Pinus koraiensis Sieb. et Zucc.), Dahurian larch ( Larix gmelinii Rupr.), Mongolian oak ( Quercus mongolica Fisch.), white birch ( Betula platyphylla Suk.), Amur Cork-Tree ( Phellodendron amurense Rupr.), Manchurian walnut ( Juglans mandshurica Maxim.), Manchurian ash ( Fraxinus mandshurica Rupr.), aspen ( Populous davidiana Dode), Mono maple ( Acer mono Maxim.), and Amur linden ( Tilia amurensis Rupr.). The mean tissue [C] across the species varied from 47.1% in fine root to 51.4% in foliage. The mean stem [C] of the 10 species was 49.9 ± 1.3% (mean ± SE). The weighted mean C concentration (WMCC) for the species ranked as: Amur Cork-Tree (55.1%) > Amur linden (53.9%) > Korean pine (53.2%) > Manchurian ash (52.9%) > Manchurian walnut (52.4%) > Mongolian oak (47.6%) > Dahurian larch (46.9%) > Mono maple (46.4%) > white birch (46.1%) > aspen (43.7%). The WMCC of the dominant Trees was negatively correlated to mean annual increment of biomass (MAI), suggesting that planting fast-growing Tree species for C sequestration in afforestation and reforestation practices sacrifice some C gain from increasing MAI due to decreasing [C]. Failing to account for the inter- and intra-specific variations in [C] will introduce a relative error of −6.7% to +7.2% in estimates of biomass C stock from inventory data, of which >93% is attributed to ignoring the inter-specific variation in [C].

Quanzhi Zhang - One of the best experts on this subject based on the ideXlab platform.

  • Heartwood and sapwood allometry of seven Chinese temperate Tree species
    Annals of Forest Science, 2010
    Co-Authors: Xingchang Wang, Quanzhi Zhang, Chuankuan Wang, Xiankuai Quan
    Abstract:

    • Allometry of sapwood/heartwood is essential for understanding Tree growth, water transport and carbon allocation, timber production and use, but such an allometry is lacking for Chinese temperate Tree species. • We studied the allometry and development of heartwood and sapwood for seven Chinese temperate Tree species: Korean pine (Pinus koraiensis Sieb. et Zucc), Dahurian larch (Larix gmelinii Rupr.), Japanese elm (Ulmus davidiana Planch var. japonica (Rehd.) Nakai), Manchurian ash (Fraxinus mandshurica Rupr.), Manchurian walnut (Juglans mandshurica Maxim.), Amur Cork-Tree (Phellodendron amurense Rupr.), and Mongolian oak (Quercus mongolica Fisch.). • All heartwood parameters investigated, including heartwood radius (HR), heartwood formation rate (HFR), heartwood ring number (HRN), heartwood initiation age (HIA), and heartwood volume ratio (HVR), were positively correlated with Tree cambial age (CA). The HR, sapwood width (SW), sapwood area (SA), heartwood and sapwood volumes were significantly related to stem diameter at breast height (DBH) or xylem diameter. There was a polynomial relationship between the sapwood ring longevity (SRL) and sapwood ring number (SRN). However, most of the allometric relationships were species-dependent. The hardwood formation patterns were different between coniferous and broadleaved Tree species. A power function was suitable to scale SA from DBH, but the exponent varied from 1.32 for the larch to 2.19 for the Cork-Tree. • Our allometry provided a practical means to assess wood development and related physiology for the temperate Tree species.

  • Carbon concentration variability of 10 Chinese temperate Tree species
    Forest Ecology and Management, 2009
    Co-Authors: Quanzhi Zhang, Xingchang Wang, Chuankuan Wang, Xiankui Quan
    Abstract:

    Abstract A mass-based carbon (C) concentration ([C]) of 50% in dry wood is widely accepted as a constant factor for conversion of biomass to C stock. However, the [C] varies with Tree species, and few data on [C] are available for the Chinese temperate Tree species. In this study, we examined inter- and intra-specific variations of [C] in biomass tissues for 10 co-occurring temperate Tree species in northeastern China. The species were Korean pine ( Pinus koraiensis Sieb. et Zucc.), Dahurian larch ( Larix gmelinii Rupr.), Mongolian oak ( Quercus mongolica Fisch.), white birch ( Betula platyphylla Suk.), Amur Cork-Tree ( Phellodendron amurense Rupr.), Manchurian walnut ( Juglans mandshurica Maxim.), Manchurian ash ( Fraxinus mandshurica Rupr.), aspen ( Populous davidiana Dode), Mono maple ( Acer mono Maxim.), and Amur linden ( Tilia amurensis Rupr.). The mean tissue [C] across the species varied from 47.1% in fine root to 51.4% in foliage. The mean stem [C] of the 10 species was 49.9 ± 1.3% (mean ± SE). The weighted mean C concentration (WMCC) for the species ranked as: Amur Cork-Tree (55.1%) > Amur linden (53.9%) > Korean pine (53.2%) > Manchurian ash (52.9%) > Manchurian walnut (52.4%) > Mongolian oak (47.6%) > Dahurian larch (46.9%) > Mono maple (46.4%) > white birch (46.1%) > aspen (43.7%). The WMCC of the dominant Trees was negatively correlated to mean annual increment of biomass (MAI), suggesting that planting fast-growing Tree species for C sequestration in afforestation and reforestation practices sacrifice some C gain from increasing MAI due to decreasing [C]. Failing to account for the inter- and intra-specific variations in [C] will introduce a relative error of −6.7% to +7.2% in estimates of biomass C stock from inventory data, of which >93% is attributed to ignoring the inter-specific variation in [C].

C. Carranca - One of the best experts on this subject based on the ideXlab platform.

  • Influence of Tree canopy on N 2 fixation by pasture legumes and soil rhizobial abundance in Mediterranean oak woodlands
    Science of The Total Environment, 2014
    Co-Authors: C. Carranca, I.v. Castro, N. Figueiredo, R. Redondo, A.r.f. Rodrigues, I. Saraiva, R. Maricato, M.a.v. Madeira
    Abstract:

    Symbiotic N2 fixation is of primordial significance in sustainable agro-forestry management as it allows reducing the use of mineral N in the production of mixed stands and by protecting the soils from degradation. Thereby, on a 2-year basis, N2 fixation was evaluated in four oak woodlands under Mediterranean conditions using a split-plot design and three replicates. 15N technique was used for determination of N2 fixation rate. Variations in environmental conditions (temperature, rainfall, radiation) by the Cork Tree canopy as well as the age of stands and pasture management can cause great differences in vegetation growth, legume N2 fixation, and soil rhizobial abundance. In the present study, non-legumes dominated the swards, in particular beneath the Tree canopy, and legumes represented only 42% of total herbage. A 2-fold biomass reduction was observed in the oldest sown pasture in relation to the medium-age sward (6 t DW ha− 1 yr− 1). Overall, competition of pasture growth for light was negligible, but soil rhizobial abundance and symbiotic N2 fixation capacity were highly favored by this environmental factor in the spring and outside the influence of Tree canopy. Nitrogen derived from the atmosphere was moderate to high (54–72%) in unsown and sown swards. Inputs of fixed N2 increased from winter to spring due to more favorable climatic conditions (temperature and light intensity) for both rhizobia and vegetation growths. Assuming a constant fixation rate at each seasonal period, N2 fixation capacity increased from about 0.10 kg N ha− 1 per day in the autumn–winter period to 0.15 kg N ha− 1 per day in spring. Belowground plant material contributed to 11% of accumulated N in pasture legumes and was not affected by canopy. Size of soil fixing bacteria contributed little to explain pasture legumes N.

  • Influence of Tree canopy on N₂ fixation by pasture legumes and soil rhizobial abundance in Mediterranean oak woodlands.
    The Science of the total environment, 2014
    Co-Authors: C. Carranca, I.v. Castro, N. Figueiredo, R. Redondo, A.r.f. Rodrigues, I. Saraiva, R. Maricato, M.a.v. Madeira
    Abstract:

    Symbiotic N2 fixation is of primordial significance in sustainable agro-forestry management as it allows reducing the use of mineral N in the production of mixed stands and by protecting the soils from degradation. Thereby, on a 2-year basis, N2 fixation was evaluated in four oak woodlands under Mediterranean conditions using a split-plot design and three replicates. (15)N technique was used for determination of N2 fixation rate. Variations in environmental conditions (temperature, rainfall, radiation) by the Cork Tree canopy as well as the age of stands and pasture management can cause great differences in vegetation growth, legume N2 fixation, and soil rhizobial abundance. In the present study, non-legumes dominated the swards, in particular beneath the Tree canopy, and legumes represented only 42% of total herbage. A 2-fold biomass reduction was observed in the oldest sown pasture in relation to the medium-age sward (6 t DW ha(-1)yr(-1)). Overall, competition of pasture growth for light was negligible, but soil rhizobial abundance and symbiotic N2 fixation capacity were highly favored by this environmental factor in the spring and outside the influence of Tree canopy. Nitrogen derived from the atmosphere was moderate to high (54-72%) in unsown and sown swards. Inputs of fixed N2 increased from winter to spring due to more favorable climatic conditions (temperature and light intensity) for both rhizobia and vegetation growths. Assuming a constant fixation rate at each seasonal period, N2 fixation capacity increased from about 0.10 kg N ha(-1) per day in the autumn-winter period to 0.15 kg N ha(-1) per day in spring. Belowground plant material contributed to 11% of accumulated N in pasture legumes and was not affected by canopy. Size of soil fixing bacteria contributed little to explain pasture legumes N.