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Naoki Makita - One of the best experts on this subject based on the ideXlab platform.

  • relationships between specific root length and respiration rate of Fine Roots across stands and seasons in chamaecyparis obtusa
    Plant and Soil, 2018
    Co-Authors: Kouhei Miyatani, Naoki Makita, Toko Tanikawa, Yasuhiro Hirano
    Abstract:

    Fine root respiration (R r ) is closely linked with Fine root morphology, especially with specific root length (SRL), in short-term measurements in some tree species. However, whether these relationships are also valid across different stands and seasons is not yet known. This study aimed to investigate these relationships in the Fine Roots of Chamaecyparis obtusa. The R r , mean root diameter, and SRL of Fine root segments of two C. obtusa stands were determined every three months over two years. We detected significant positive correlations between R r and SRL of Fine root segments across the stands over two years. The relationship of R r with SRL was stronger than that with the mean diameter of Fine Roots. The slopes and intercepts for the R r and SRL relationships did not differ among stands and measurement times. Further, we proposed a simple approach for estimating CO2 flux from Fine Roots at the stand level based on SRL and confirmed that the ranges of estimated CO2 values were comparable with those of values reported using the conventional approach. The Fine root morphology typified by SRL is a key variable in R r of Fine Roots and CO2 flux at the stand level.

  • biomass and morphology of Fine Roots in eight cryptomeria japonica stands in soils with different acid buffering capacities
    Forest Ecology and Management, 2017
    Co-Authors: Yasuhiro Hirano, Toko Tanikawa, Naoki Makita
    Abstract:

    Abstract Cryptomeria japonica, which is one of the main silvicultural species in Japan, accumulates calcium (Ca) in soils with high acid buffering capacity (ABC) but has depleted Ca in soils with low-ABC over the past two decades. However, the contribution of Fine Roots in C. japonica to the accumulation or depletion of Ca in soils with different ABCs has not been evaluated. The aim of this study was to clarify the responses of C. japonica Fine Roots in terms of biomass and morphology in eight plantation stands to soils with two contrasting ABCs, which have different trends of soil acidification. We evaluated the biomass and specific root length (SRL) of Fine Roots divided into three diameter classes (

  • very Fine Roots respond to soil depth biomass allocation morphology and physiology in a broad leaved temperate forest
    Ecological Research, 2011
    Co-Authors: Naoki Makita, Yasuhiro Hirano, Takeo Mizoguchi, Yuji Kominami, Masako Dannoura, Hiroaki Ishii, Leena Finer, Yoichi Kanazawa
    Abstract:

    Very Fine Roots (<0.5 mm in diameter) of forest trees may serve as better indicators of root function than the traditional category of <2 mm, but how these Roots will exhibit the plasticity of species-specific traits in response to heterogeneous soil nutrients is unknown. Here, we examined the vertical distribution of biomass and morphological and physiological traits of Fine Roots across three narrow diameter classes (<0.5, 0.5–1.0, and 1.0–2.0 mm) of Quercus serrata and Ilex pedunculosa at five soil depths down to 50 cm in a broad-leaved temperate forest. In both species, biomass and the allocation of very Fine Roots were higher in the surface soil but lower below 10-cm soil depth compared to values for larger Roots (0.5–2.0 mm). When we applied these diameter classes, only very Fine Roots of Q. serrata exhibited significant changes in specific root length (SRL; m g−1) and root nitrogen (N) concentrations with soil depth, whereas the N concentrations only changed significantly in I. pedunculosa. The SRL and root N concentrations of larger Roots in the two species did not significantly differ among soil depths. Thus, very Fine Roots may exhibit species-specific traits and change their potential for nutrient and water uptake in response to soil depth by plasticity in root biomass, the length, and the N in response to available resources.

  • Very Fine Roots respond to soil depth: biomass allocation, morphology, and physiology in a broad‐leaved temperate forest
    Ecological Research, 2010
    Co-Authors: Naoki Makita, Yasuhiro Hirano, Takeo Mizoguchi, Yuji Kominami, Masako Dannoura, Hiroaki Ishii, Leena Finer, Yoichi Kanazawa
    Abstract:

    Very Fine Roots (

Yasuhiro Hirano - One of the best experts on this subject based on the ideXlab platform.

  • relationships between specific root length and respiration rate of Fine Roots across stands and seasons in chamaecyparis obtusa
    Plant and Soil, 2018
    Co-Authors: Kouhei Miyatani, Naoki Makita, Toko Tanikawa, Yasuhiro Hirano
    Abstract:

    Fine root respiration (R r ) is closely linked with Fine root morphology, especially with specific root length (SRL), in short-term measurements in some tree species. However, whether these relationships are also valid across different stands and seasons is not yet known. This study aimed to investigate these relationships in the Fine Roots of Chamaecyparis obtusa. The R r , mean root diameter, and SRL of Fine root segments of two C. obtusa stands were determined every three months over two years. We detected significant positive correlations between R r and SRL of Fine root segments across the stands over two years. The relationship of R r with SRL was stronger than that with the mean diameter of Fine Roots. The slopes and intercepts for the R r and SRL relationships did not differ among stands and measurement times. Further, we proposed a simple approach for estimating CO2 flux from Fine Roots at the stand level based on SRL and confirmed that the ranges of estimated CO2 values were comparable with those of values reported using the conventional approach. The Fine root morphology typified by SRL is a key variable in R r of Fine Roots and CO2 flux at the stand level.

  • biomass and morphology of Fine Roots in eight cryptomeria japonica stands in soils with different acid buffering capacities
    Forest Ecology and Management, 2017
    Co-Authors: Yasuhiro Hirano, Toko Tanikawa, Naoki Makita
    Abstract:

    Abstract Cryptomeria japonica, which is one of the main silvicultural species in Japan, accumulates calcium (Ca) in soils with high acid buffering capacity (ABC) but has depleted Ca in soils with low-ABC over the past two decades. However, the contribution of Fine Roots in C. japonica to the accumulation or depletion of Ca in soils with different ABCs has not been evaluated. The aim of this study was to clarify the responses of C. japonica Fine Roots in terms of biomass and morphology in eight plantation stands to soils with two contrasting ABCs, which have different trends of soil acidification. We evaluated the biomass and specific root length (SRL) of Fine Roots divided into three diameter classes (

  • very Fine Roots respond to soil depth biomass allocation morphology and physiology in a broad leaved temperate forest
    Ecological Research, 2011
    Co-Authors: Naoki Makita, Yasuhiro Hirano, Takeo Mizoguchi, Yuji Kominami, Masako Dannoura, Hiroaki Ishii, Leena Finer, Yoichi Kanazawa
    Abstract:

    Very Fine Roots (<0.5 mm in diameter) of forest trees may serve as better indicators of root function than the traditional category of <2 mm, but how these Roots will exhibit the plasticity of species-specific traits in response to heterogeneous soil nutrients is unknown. Here, we examined the vertical distribution of biomass and morphological and physiological traits of Fine Roots across three narrow diameter classes (<0.5, 0.5–1.0, and 1.0–2.0 mm) of Quercus serrata and Ilex pedunculosa at five soil depths down to 50 cm in a broad-leaved temperate forest. In both species, biomass and the allocation of very Fine Roots were higher in the surface soil but lower below 10-cm soil depth compared to values for larger Roots (0.5–2.0 mm). When we applied these diameter classes, only very Fine Roots of Q. serrata exhibited significant changes in specific root length (SRL; m g−1) and root nitrogen (N) concentrations with soil depth, whereas the N concentrations only changed significantly in I. pedunculosa. The SRL and root N concentrations of larger Roots in the two species did not significantly differ among soil depths. Thus, very Fine Roots may exhibit species-specific traits and change their potential for nutrient and water uptake in response to soil depth by plasticity in root biomass, the length, and the N in response to available resources.

  • Very Fine Roots respond to soil depth: biomass allocation, morphology, and physiology in a broad‐leaved temperate forest
    Ecological Research, 2010
    Co-Authors: Naoki Makita, Yasuhiro Hirano, Takeo Mizoguchi, Yuji Kominami, Masako Dannoura, Hiroaki Ishii, Leena Finer, Yoichi Kanazawa
    Abstract:

    Very Fine Roots (

Kurt S Pregitzer - One of the best experts on this subject based on the ideXlab platform.

  • Fine Roots are the dominant source of recalcitrant plant litter in sugar maple dominated northern hardwood forests
    New Phytologist, 2015
    Co-Authors: Alan F Talhelm, Kurt S Pregitzer
    Abstract:

    Summary � Most studies of forest litter dynamics examine the biochemical characteristics and decomposition of leaf litter, but Fine Roots are also a large source of litter in forests. � We quantified the concentrations of eight biochemical fractions and nitrogen (N) in leaf litter and Fine Roots at four sugar maple (Acer saccharum)-dominated hardwood forests in the north-central United States. We combined these results with litter production data to estimate ecosystem biochemical fluxes to soil. We also compared how leaf litter and Fine root biochemistry responded to long-term simulated N deposition. � Compared with leaf litter, Fine Roots contained 2.9-fold higher acid-insoluble fraction (AIF) and 2.3-fold more condensed tannins; both are relatively difficult to decompose. Comparatively, leaf litter had greater quantities of more labile components: nonstructural carbohydrates, cellulose and soluble phenolics. At an ecosystem scale, Fine Roots contributed over two-thirds of the fluxes of AIF and condensed tannins to soil. Fine root biochemistry was also less responsive than leaf litter to long-term simulated N deposition. � Fine Roots were the dominant source of difficult-to-decompose plant carbon fractions entering the soil at our four study sites. Based on our synthesis of the literature, this pattern appears to be widespread in boreal and temperate forests.

  • atmospheric co2 soil nitrogen and turnover of Fine Roots
    New Phytologist, 1995
    Co-Authors: Kurt S Pregitzer, Peter S Curtis, Mark E Kubiske, James A Teeri, Christoph S Vogel
    Abstract:

    summary In most natural ecosystems a significant portion of carbon fixed through photosynthesis is allocated to the production and maintenance of Fine Roots, the ephemeral portion of the root system that absorbs growth-limiting moisture and nutrients. In turn, senescence of Fine Roots can be the greatest source of C input to forest soils. Consequently, important questions in ecology entail the extent to which increasing atmospheric CO2 may alter the allocation of carbon to, and demography of, Fine Roots. Using microvideo and image analysis technology, we demonstrate that elevated atmospheric CO2 increases the rates of both Fine root production and mortality. Rates of root mortality also increased substantially as soil nitrogen availability increased, regardless of CO2 concentration. Nitrogen greatly influenced the proportional allocation of carbon to leaves vs. Fine Roots. The amount of available nitrogen in the soil appears to be the most important factor regulating Fine root demography in Populus trees.

Ivano Brunner - One of the best experts on this subject based on the ideXlab platform.

  • The Dynamics of Living and Dead Fine Roots of Forest Biomes across the Northern Hemisphere
    Forests, 2019
    Co-Authors: Cunguo Wang, Ivano Brunner, Shengwei Zong, Mai-he Li
    Abstract:

    Research Highlights: A detailed picture of the seasonality in Fine root biomass (FRB), necromass (FRN), and the biomass/necromass ratio (FRBN) throughout the whole year is crucial to uncover profound effects of long-term environmental changes on Fine root dynamics. Materials and Methods: We used meta-analysis to characterize the variability of FRB, FRN and FRBN, and determined their relations with climatic (monthly versus annual), edaphic and geomorphic factors for tropical, temperate and boreal forest biomes across the Northern Hemisphere. Results: Boreal forests exhibited the highest FRB and FRN, while tropical forests yielded the lowest FRN, and thus the greatest FRBN. FRB and FRN significantly decreased with sampling depth, but increased with soil organic carbon content and elevation, while an opposite pattern was found for FRBN. Temperature and precipitation at different time scales (monthly versus annual) and latitude had varying influences on Fine Roots. High FRB and FRN were observed during dry season for tropical forests, but in the late growing season for temperate forests. The three forest biomes exhibited the high root activity (measured as FRBN) in June or July. Conclusions: It is crucial to realize the universal and specific responses of Fine Roots to multiple environmental factors when attempting to incorporate these parameters into Fine root monthly dynamic models in forest ecosystems. The biome-specific fluctuation of Fine Roots contributes to identify the influence factors on Fine root seasonal patterns throughout the whole year. Our analysis is expected to improve the understanding of the key role of Fine Roots at monthly level in modeling and predicting carbon budget of various forest biomes under future climate change.

  • Unravelling the age of Fine Roots of temperate and boreal forests
    Nature Communications, 2018
    Co-Authors: Emily F. Solly, Heljä-sisko Helmisaari, Ivano Brunner, Claude Herzog, Jaana Leppälammi-kujansuu, Ingo Schöning, Marion Schrumpf, Fritz H. Schweingruber, Susan E. Trumbore, Frank Hagedorn
    Abstract:

    Fine Roots support the water and nutrient demands of plants and supply carbon to soils. Quantifying turnover times of Fine Roots is crucial for modeling soil organic matter dynamics and constraining carbon cycle–climate feedbacks. Here we challenge widely used isotope based estimates suggesting the turnover of Fine Roots of trees to be as slow as a decade. By recording annual growth rings of Roots from woody plant species, we show that mean chronological ages of Fine Roots vary from

  • unravelling the age of Fine Roots of temperate and boreal forests
    Nature Communications, 2018
    Co-Authors: Heljä-sisko Helmisaari, Emily F. Solly, Ivano Brunner, Claude Herzog, Ingo Schöning, Marion Schrumpf, Fritz H. Schweingruber, Jaana Leppalammikujansuu, Susan E. Trumbore
    Abstract:

    Fine Roots support the water and nutrient demands of plants and supply carbon to soils. Quantifying turnover times of Fine Roots is crucial for modeling soil organic matter dynamics and constraining carbon cycle–climate feedbacks. Here we challenge widely used isotope-based estimates suggesting the turnover of Fine Roots of trees to be as slow as a decade. By recording annual growth rings of Roots from woody plant species, we show that mean chronological ages of Fine Roots vary from <1 to 12 years in temperate, boreal and sub-arctic forests. Radiocarbon dating reveals the same Roots to be constructed from 10 ± 1 year (mean ± 1 SE) older carbon. This dramatic difference provides evidence for a time lag between plant carbon assimilation and production of Fine Roots, most likely due to internal carbon storage. The high root turnover documented here implies greater carbon inputs into soils than previously thought which has wide-ranging implications for quantifying ecosystem carbon allocation. Fine-root lifetimes and carbon inputs from Roots into soil impact carbon cycle-climate feedbacks yet remain poorly constrained. Here, using annual-growth rings and radiocarbon dating, the authors show that the chronological age of Fine Roots is substantially younger than that of the carbon used for their growth.

  • morphological and physiological responses of scots pine Fine Roots to water supply in a dry climatic region in switzerland
    Tree Physiology, 2009
    Co-Authors: Ivano Brunner, Beat Frey, Elisabeth Graf Pannatier, Andreas Rigling, W Landolt, Stephan Zimmermann, Matthias Dobbertin
    Abstract:

    : In recent decades, Scots pine (Pinus sylvestris L.) forests in inner-Alpine dry valleys of Switzerland have suffered from drought and elevated temperatures, resulting in a higher mortality rate of trees than the mean mortality rate in Switzerland. We investigated the responses of Fine Roots (standing crop, morphological and physiological features) to water supply in a Scots pine forest in the Rhone valley. Before irrigation started in 2003, low- and high-productivity Scots pine trees were selected based on their crown transparency. The Fine root standing crop measured in spring from 2003 to 2005 was unaffected by the irrigation treatment. However, irrigation significantly enhanced the Fine root standing crop during the vegetation period when values from spring were compared with values from fall in 2005. Irrigation slightly increased specific root length but decreased root tissue density. Fine root O2-consumption capacity decreased slightly in response to the irrigation treatment. Using ingrowth cores to observe the responses of newly produced Fine Roots, irrigation had a significantly positive effect on the length of Fine Roots, but there were no differences between the low- and high-productivity trees. In contrast to the weak response of Fine Roots to irrigation, the aboveground parts responded positively to irrigation with more dense crowns. The lack of a marked response of the Fine root biomass to irrigation in the low- and high-productivity trees suggests that Fine Roots have a high priority for within-tree carbon allocation.

  • heavy metal accumulation and phytostabilisation potential of tree Fine Roots in a contaminated soil
    Environmental Pollution, 2008
    Co-Authors: Ivano Brunner, Jorg Luster, Madeleine S Gunthardtgoerg, Beat Frey
    Abstract:

    Root systems of Norway spruce (Picea abies) and poplar (Populus tremula) were long-term exposed to metal-contaminated soils in open-top chambers to investigate the accumulation of the heavy metals in the Fine Roots and to assess the plants suitability for phytostabilisation. The heavy metals from the contaminated soil accumulated in the Fine Roots about 10-20 times more than in the controls. The capacity to bind heavy metals already reached its maximum after the first vegetation period. Fine Roots of spruce tend to accumulate more heavy metals than poplar. Copper and Zinc were mainly detected in the cell walls with larger values in the epidermis than in the cortex. The heavy metals accumulated in the Fine Roots made up 0.03-0.2% of the total amount in the soils. We conclude that tree Fine Roots adapt well to conditions with heavy metal contamination, but their phytostabilisation capabilities seem to be very low.

Guangshui Chen - One of the best experts on this subject based on the ideXlab platform.

  • allometry of Fine Roots in forest ecosystems
    Ecology Letters, 2019
    Co-Authors: Guangshui Chen, Sarah E Hobbie, Peter B Reich, Yusheng Yang, David Robinson
    Abstract:

    : Theoretical predictions regarding Fine root production are needed in many ecosystem models but are lacking. Here, we expand the classic pipe model to Fine Roots and predict isometric scaling relationships between leaf and Fine root biomass and among all major biomass production components of individual trees. We also predict that Fine root production scales more slowly against increases in leaf production across global forest ecosystems at the stand level. Using meta-analysis, we show Fine root biomass scales isometrically against leaf biomass both at the individual tree and stand level. However, despite isometric scaling between stem and coarse root production, Fine root production scales against leaf production with a slope of about 0.8 at the stand level, which probably results from more rapid increase of turnover rate in leaves than in Fine Roots. These analyses help to improve our understandings of allometric theory and controls of belowground C processes.

  • Decomposition dynamic of Fine Roots in a mixed forest of Cunninghamia lanceolata and Tsoongiodendron odorum in mid-subtropics
    Annals of Forest Science, 2004
    Co-Authors: Yusheng Yang, Guangshui Chen
    Abstract:

    Decomposition of Fine Roots (< 2 mm in diameter, viz. < 0.5 mm, 0.5-1.0 mm, 1.0-2.0 mm) was studied by means of litter bag in a mixed forest of Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.) and Tsoong's tree (Tsoongiodendron odorum Chun) in Sanming, Fujian, China. In a 540 d period of decay, Fine Roots in all litter bags decomposed in a three-phase manner: (a) for the Chinese fir, an initial, relatively low rate of decay up to 90 d followed by a period of rapid weight loss until 270 d, and then by a phase of slow decay rate; (b) for the Tsoong's tree, a rapid loss period between 0-60 d followed by a relatively rapid loss period between 60-360 d, and then a slow loss period between 360-540 d occurred. The mass loss after 1 yr of decomposition ranged from 58.5% to 63.3% for the Chinese fir and 68.8% to 78.2% for the Tsoong's tree. Fine Roots with a larger diameter had a lower rate of mass loss. Consistent increase in lignin concentration and decrease in absolute amount of phosphorus (P) were found for Fine Roots of the two tree species during decomposition. The absolute amounts of nitrogen (N) increased a little initially in the Fine Roots of the Chinese fir during a short duration. In contrast, the Fine Roots of Tsoong's tree were releasing N from the outset. The chemical composition controlled decomposition rate and it was found a change of TNC (total nonstructural carbohydrates)-regulating in the initial decomposition phase to lignin- or N-regulating in the second phase, and P- or lignin-regulating in the last phase.