Hardware and software efficacy in assessment of fine root diameter distributions

The relationships between arbuscular mycorrhizal fungi and root morphological characteristics were studied under greenhouse conditions of 78 tropical native woody species and 47 seedling species collected in the field. Seedlings of native woody pioneer and early secondary species that generally exhibited fine roots with a dense cover of long root hairs showed higher mycorrhizal response and root mycorrhizal colonization than late-secondary and climax species with coarse roots with a sparse cover of short root hairs. Root-hair length and incidence decreased with the progression among the successional groups while fine-root diameter increased, both in the greenhouse and in the field. The mycorrhizal response was highly correlated to root mycorrhizal colonization in the greenhouse and in the field. These parameters were inversely correlated with the seed mass and fine-root diameter, but directly correlated with root-hair incidence, both in the greenhouse and in the field. Mycorrhizal response and root mycorrhizal colonization were also directly correlated with the root-hair length and root/shoot ratio of uninoculated plants. The seedling mycorrhizal status of the early successional woody species suggests that the root traits of these fast-growing species can be more receptive to attraction, infection and colonization by arbuscular mycorrhizas than root traits of late-successional species.

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Estimating fine root longevity in a temperate Norway spruce forest using three independent methods

Functional Plant Biology ◽

10.1071/fp08195 ◽

2009 ◽

Vol 36 (1) ◽

pp. 11 ◽

Cited By ~ 40

Author(s):

Dirk Gaul ◽

Dietrich Hertel ◽

Christoph Leuschner

Keyword(s):

Norway Spruce ◽

Fine Root ◽

Soil Depth ◽

Mineral Soil ◽

Mean Value ◽

Root Diameter ◽

Organic Layer ◽

Mean Values ◽

Root Longevity ◽

Fine Root Longevity

The importance of root systems for C cycling depends crucially on fine root longevity. We investigated mean values for fine root longevity with root diameter, root C/N ratio and soil depth using radiocarbon (14C) analyses in a temperate Norway spruce [Picea abies (L.) Karst.] forest. In addition, we applied sequential soil coring and minirhizotron observations to estimate fine root longevity in the organic layer of the same stand. The mean radiocarbon age of C in fine roots increased with depth from 5 years in the organic layer to 13 years in 40–60 cm mineral soil depth. Similarly, the C/N ratios of fine root samples were lowest in the organic layer with a mean value of 24 and increased with soil depth. Roots >0.5 mm in diameter tended to live longer than those being <0.5 mm in diameter. By far the strongest variability in fine root longevity estimates was due to the chosen method of investigation, with radiocarbon analyses yielding much higher estimates (5.4 years) than sequential soil coring (0.9 years) and minirhizotron observations (0.7 years). We conclude that sequential soil coring and minirhizotron observations are likely to underestimate mean fine root longevity, and radiocarbon analyses may lead to an overestimation of mean root longevity.

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Bimodal root diameter distributions in Serengeti grasses exhibit plasticity in response to defoliation and soil texture: implications for nitrogen uptake

Functional Ecology ◽

10.1111/j.1365-2435.2006.01192.x ◽

2007 ◽

Vol 21 (1) ◽

Cited By ~ 16

Author(s):

T. M. ANDERSON ◽

W. T. STARMER ◽

M. THORNE

Keyword(s):

Nitrogen Uptake ◽

Soil Texture ◽

Root Diameter ◽

Diameter Distributions

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The Right-Skewed Distribution of Fine-Root Size in Three Temperate Forests in Northeastern China

Frontiers in Plant Science ◽

10.3389/fpls.2021.772463 ◽

2022 ◽

Vol 12 ◽

Author(s):

Cunguo Wang ◽

Ivano Brunner ◽

Junni Wang ◽

Wei Guo ◽

Zhenzhen Geng ◽

...

Keyword(s):

Tree Species ◽

Fine Roots ◽

Fine Root ◽

Root Diameter ◽

Northeastern China ◽

Skewed Distribution ◽

Root Number ◽

First Order ◽

Fine Root Length ◽

Root Size

Trees can build fine-root systems with high variation in root size (e.g., fine-root diameter) and root number (e.g., branching pattern) to optimize belowground resource acquisition in forest ecosystems. Compared with leaves, which are visible above ground, information about the distribution and inequality of fine-root size and about key associations between fine-root size and number is still limited. We collected 27,573 first-order fine-roots growing out of 3,848 second-order fine-roots, covering 51 tree species in three temperate forests (Changbai Mountain, CBS; Xianrendong, XRD; and Maoershan, MES) in Northeastern China. We investigated the distribution and inequality of fine-root length, diameter and area (fine-root size), and their trade-off with fine-root branching intensity and ratio (fine-root number). Our results showed a strong right-skewed distribution in first-order fine-root size across various tree species. Unimodal frequency distributions were observed in all three of the sampled forests for first-order fine-root length and area and in CBS and XRD for first-order fine-root diameter, whereas a marked bimodal frequency distribution of first-order fine-root diameter appeared in MES. Moreover, XRD had the highest and MES had the lowest inequality values (Gini coefficients) in first-order fine-root diameter. First-order fine-root size showed a consistently linear decline with increasing root number. Our findings suggest a common right-skewed distribution with unimodality or bimodality of fine-root size and a generalized trade-off between fine-root size and number across the temperate tree species. Our results will greatly improve our thorough understanding of the belowground resource acquisition strategies of temperate trees and forests.

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VARIATIONS OF FINE ROOT DIAMETER WITH ROOT ORDER IN MANCHURIAN ASH AND DAHURIAN LARCH PLANTATIONS

Chinese Journal of Plant Ecology ◽

10.17521/cjpe.2005.0123 ◽

2005 ◽

Vol 29 (6) ◽

pp. 871-877

Author(s):

WANG Xiang-Rong ◽

◽

WANG Zheng-Quan ◽

HAN You-Zhi ◽

GU Jia-Cun ◽

...

Keyword(s):

Fine Root ◽

Root Diameter ◽

Dahurian Larch ◽

Root Order ◽

Manchurian Ash ◽

Dahurian Larch Plantations

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Decoupled drought responses of fine-root versus leaf acquisitive traits among six Prunus hybrids

Journal of Plant Ecology ◽

10.1093/jpe/rtaa015 ◽

2020 ◽

Vol 13 (3) ◽

pp. 304-312

Author(s):

Shuang-Xi Zhou ◽

Rob R Walker ◽

Everard Edwards

Keyword(s):

Drought Stress ◽

Fine Root ◽

Root Traits ◽

Resource Conservation ◽

Root Diameter ◽

Root Trait ◽

Soil Drought ◽

Drought Response ◽

Severe Drought ◽

Significant Change

Abstract Aims Predicting drought consequences on forests and fruit crop plantings requires improved understanding of drought responses of both leaf and fine-root resource acquisitive traits (specific leaf area—SLA, specific root surface area—SRA and specific root length—SRL). We hypothesize their responses are coordinated towards integrated plant resource conservation under severe drought. Methods We tested the hypothesis with a greenhouse-based drought experiment on saplings of six Prunus hybrids with a priori known contrasting drought sensitivity. Saplings were subjected to either control (100% field capacity) or severe drought stress treatment (33% evapotranspiration of hybrid-specific control plants). Sample collections were carried out at 30 and at 60 days after the start of treatments, for both control and stressed saplings. Important Findings No hybrid showed concurrent significant decrease of SLA and SRA (or SRL) under severe drought. The fine-root traits of the six hybrids showed two major drought-response scenarios, in particular: (i) increased root tissue density (RTD) and decreased average root diameter without significant change of SRL and (ii) increased RTD and decreased SRL without significant change of average root diameter. Drought responses of leaf gas exchange, SRA, SRL and RTD were closely correlated along a gradient towards resource conservation from control to drought-stressed plants in all hybrids, which was orthogonal to another gradient characterized by a hybrid-dependent decrease of SLA. These findings highlight (i) the multi-dimensionality of root-trait drought responses, (ii) the decoupling between leaf economics and leaf hydraulics and (iii) the covariation of leaf and root hydraulics in terms of trait drought responses. The study contributes to identifying the origin of the multi-dimensionality of root-trait drought response at intraspecific scale, and highlights differential drought–response combinations of leaf and fine-root traits among hybrids to survive under severe soil drought stress.

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Root distribution of Acacia mangium Willd. and Macaranga tanarius L. of rainforest

Bangladesh Journal of Botany ◽

10.3329/bjb.v43i2.21665 ◽

2015 ◽

Vol 43 (2) ◽

pp. 141-145 ◽

Cited By ~ 1

Author(s):

Nazi Avani ◽

Habibah Lateh ◽

Ghassem Habibi Bibalani

Keyword(s):

Fine Root ◽

Acacia Mangium ◽

Root Diameter ◽

Shallow Landslide ◽

Soil Reinforcement ◽

Surface Erosion ◽

Diameter Class ◽

Root Area ◽

Class D ◽

Macaranga Tanarius

The number of roots and root area ratio (RAR) decreased with depth in Acacia mangium and Macaranga tanarius and the maximum value of RAR and root number were observed in the first layer of soil. This process was regular in Acacia mangium Willd., but the RAR value showed great variability in Macaranga tanarius L. as the RAR decreased with depth until the second layer (20 cm) and increased again. About 35% of all roots in A. mangium, and about 50% of all roots in M. tanarius are located in the first layer. About 87% of all roots were in the fine root diameter class (d < 2 mm) in M. tanarius species. However 90% of all roots were in the fine root diameter class in A. magnium species. Fine roots contribution to soil reinforcement due to concentration on upper levels, prevent surface erosion and shallow landslide. These results will be useful for slope stability projects. DOI: http://dx.doi.org/10.3329/bjb.v43i2.21665 Bangladesh J. Bot. 43(2): 141-145, 2014 (September)

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Inherent and Stress-Induced Responses of Fine Root Morphology and Anatomy in Commercial Grapevine Rootstocks with Contrasting Drought Resistance

Plants ◽

10.3390/plants10061121 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1121

Author(s):

Idan Reingwirtz ◽

Jake Uretsky ◽

Italo F. Cuneo ◽

Thorsten Knipfer ◽

Clarissa Reyes ◽

...

Keyword(s):

Drought Stress ◽

Drought Resistance ◽

Root Morphology ◽

Root Length ◽

Fine Root ◽

Lateral Roots ◽

Root Diameter ◽

Root Tip ◽

Soil Conditions ◽

Plant Materials

Some grapevine rootstocks perform better than others during and after drought events, yet it is not clear how inherent and stress-induced differences in root morphology and anatomy along the length of fine roots are involved in these responses. Using a variety of growing conditions and plant materials, we observed significant differences in root diameter, specific root length (SRL) and root diameter distribution between two commonly used commercial grapevine rootstocks: Richter 110 (110R; drought resistant) and Millardet et de Grasset 101-14 (101-14Mgt; drought sensitive). The 110R consistently showed greater root diameters with smaller SRL and proportion of root length comprised of fine lateral roots. The 110R also exhibited significantly greater distance from tip to nearest lateral, longer white root length, and larger proportion of root length that is white under drought stress. Mapping of fine root cortical lacunae showed similar patterns between the rootstocks; mechanical failure of cortical cells was common in the maturation zone, limited near the root tip, and increased with drought stress for both genotypes; however, lacuna formed under wetter soil conditions in 110R. Results suggest that drought resistance in grapevine rootstocks is associated with thick, limitedly branched roots with a larger proportion of white-functional roots that tend to form lacuna under more mild water deficit, all of which likely favor continued resource acquisition at depth.

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Variations of fine root diameter with root order in Manchurian ash and Dahurian larch plantations

Frontiers of Forestry in China ◽

10.1007/s11461-007-0005-4 ◽

2007 ◽

Vol 2 (1) ◽

pp. 34-39 ◽

Cited By ~ 3

Author(s):

Xiangrong Wang ◽

Zhengquan Wang ◽

Youzhi Han ◽

Jiacun Gu ◽

Dali Guo ◽

...

Keyword(s):

Fine Root ◽

Root Diameter ◽

Dahurian Larch ◽

Root Order ◽

Manchurian Ash ◽

Dahurian Larch Plantations

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Root biomass and root fractal analyses of an open Eucalyptus forest in a savanna of north Australia

Australian Journal of Botany ◽

10.1071/bt01054 ◽

2002 ◽

Vol 50 (1) ◽

pp. 31 ◽

Cited By ~ 53

Author(s):

D. Eamus ◽

X. Chen ◽

G. Kelley ◽

L. B. Hutley

Keyword(s):

Root Biomass ◽

Fine Root ◽

Fine Root Biomass ◽

Root Diameter ◽

Above Ground Biomass ◽

Breast Height ◽

Ground Biomass ◽

Fractal Analyses ◽

Below Ground ◽

Tree Stem

Below-ground biomass of a Eucalyptus savanna forest was estimated following trenching to depths of 2 m around 16 mature trees in a tropical savanna of north Australia. Correlations among below-ground and various components of above-ground biomass were also investigated. In addition, root morphology was investigated by fractal analyses and a determination of an index of shallow-rootedness was undertaken. Total root biomass was 38.4 t ha–1, including 1 t ha–1 of fine roots. About 77–90&percnt; of total root biomass was found in the upper 0.5 m of soil. While fine-root biomass density was approximately constant (0.1 kg m–3) in the top soil, irrespective of distance from a tree stem, coarse-root biomass showed large variation with distance from the tree stem. Significant positive correlations among total root biomass, total above-ground biomass, diameter at breast height, leaf biomass and leaf area were obtained. It is likely that total root biomass can be reasonably accurately estimated from aboveground biomass and fine-root biomass from tree leaf area. We present equations that allow the prediction of belowground biomass from above-ground measures of tree size. Root morphology of two evergreen and two deciduous species was compared by the use of three parameters. These were the fractal dimension (d), which describes root system complexity; a proportionality factor (α), which is the ratio of the cross-sectional area before and after branching; and two indices of shallow-rootedness (ISR). Roots were found to be amenable to fractal analyses. The proportionality factor was independent of root diameter (Dr) at any branching level in all tree species examined, indicating that branching patterns were similar across all root sizes. The fractal dimension (d) ranged from 1.15 to 1.36, indicating a relatively simple root structure. Mean d was significantly different between E. tetrodonta (evergreen) and T. ferdinandiana (deciduous); however, no significant differences were found among other pairs of species. Terminalia ferdinandiana had the highest ISR, while Planchonia careya (deciduous) had the lowest. In addition, differences in ISR between P. careya and the other three species were significant, but not significant among E. miniata, E. tetrodonta and T. ferdinandiana. There were clear relationships among above-ground tree stem diameter at breast height, stem base diameter, and horizontal and vertical proximal root diameter. By the use of mean values of and stem diameter, we estimated the total crosssectional area of root and root diameter-class distribution for each species studied.

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