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Maqbool MN, Aftab F. An Efficient Propagation Approach to Forcing Softwood Shoots from Epicormic Buds and Subsequent Rooting of Paulownia elongata S. Y. Hu. SCIENTIFICA 2024; 2024:1515489. [PMID: 38812716 PMCID: PMC11136545 DOI: 10.1155/2024/1515489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 04/09/2024] [Accepted: 04/10/2024] [Indexed: 05/31/2024]
Abstract
The current research describes the multiplication of Paulownia elongata S. Y. Hu, a timber plant, through the forcing of softwood shoots from epicormic buds under glasshouse conditions in spring and fall seasons. Different growth media were used to compare their effect on the forcing potential of epicormic buds. For this, 25-30-cm-long and 1.2-2-cm-diameter stem segments taken from the lower juvenile portion of a mother plant were placed horizontally in flat trays containing media, i.e., sterilized well-moistened sand, peat moss, perlite, and vermiculite individually. Furthermore, 4-6-cm-long forced softwood shoots were detached and treated with various concentrations of IBA (indole-3-butyric acid) and NAA (α-naphthyl acetic acid) either individually or in combinations for subsequent rooting. The response of shoot forcing was better in spring as compared to fall in terms of shoot length (cm), and number of shoots or leaves; however, an earlier bud break was observed during fall after 30 days of the initial experiment. The use of peat moss and vermiculite proved to be equally suitable for early bud break in both seasons, whereas in terms of shoot and leaf number as well as the shoot length (cm), the best outcome was observed in sand. Best rooting was observed at 3 gL-1 IBA + 3 gL-1 NAA in terms of root number per shoot, root length (cm), and days to root initiation while using sand as the growth medium after 50 days of the rooting experiment. The successfully established plantlets were further shifted to soil at Botanical Garden, University of the Punjab, Lahore, Pakistan, exhibiting an 87.5% survival rate. On the basis of the results obtained, it may be concluded that reasonable softwood shoot forcing in P. elongata may further be exploited for its mass scale nursery propagation as well as use in future in vitro studies.
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Affiliation(s)
| | - Faheem Aftab
- Institute of Botany, University of the Punjab, Lahore, Pakistan
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Hydrodynamic Limitations to Mangrove Seedling Retention in Subtropical Estuaries. SUSTAINABILITY 2022. [DOI: 10.3390/su14148605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Mangrove-forest sustainability hinges upon propagule recruitment and seedling retention. This study evaluates biophysical limitations to mangrove-seedling persistence by measuring anchoring force of two mangrove species (Rhizophora mangle L. and Avicennia germinans (L.) L.). Anchoring force was measured in 362 seedlings via lateral pull tests administered in mangrove forests of two subtropical estuaries and in laboratory-based experiments. Removal mechanism varied with seedling age: newly established seedlings failed due to root pull-out while seedlings older than 3 months failed by root breakage. The anchoring force of R. mangle seedlings was consistently and significantly greater than A. germinans (p = 0.002); however, force to remove A. germinans seedlings increased with growth at a faster rate (p < 0.001; A. germinans: 0.20–0.23 N/g biomass; R. mangle: 0.04–0.07 N/g biomass). Increasing density of surrounding vegetation had a positive effect (p = 0.04) on anchoring force of both species. Critical velocities at which seedlings become susceptible to instantaneous uprooting estimated from anchoring forces measured in the field were 1.20 m/s and 1.50 m/s, respectively, for R. mangle and A. germinans. As estimated critical velocities exceed typical flow magnitudes observed in field sites, removal of established seedlings likely occurs following erosion of sediments from the seedling base.
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Lozanovska I, Rivaes R, Vieira C, Ferreira MT, Aguiar FC. Streamflow regulation effects in the Mediterranean rivers: How far and to what extent are aquatic and riparian communities affected? THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 749:141616. [PMID: 32827828 DOI: 10.1016/j.scitotenv.2020.141616] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 08/08/2020] [Accepted: 08/08/2020] [Indexed: 06/11/2023]
Abstract
Dam-induced disruption of the natural continuum of rivers has manifold consequences on fluvial ecosystems, but how distinct plant groups and plant adaptive strategies can mediate the regulation effects is largely unexplored. In this work, we focused on how different plant groups (macrophytes, bryophytes, and riparian woody vegetation) respond to hydrological alterations along the river and across the riparian zone downstream of dams. We specifically aimed to determine the degree of regulation [DOR] and distance from dam [DFD], where river regulation no longer significantly affects plant communities in two case studies - a run-of-river dam and a reservoir in Portugal. We collected data on plant species cover in 7 unregulated and 24 regulated sites in June-July 2019. We performed a cluster and ordination analysis to derive guilds using flow-responsive traits and applied linear models to predict guild alterations along the gradient of DOR and DFD. We established three macrophytes, six bryophytes, and five riparian guilds. Our results showed that the vegetation response to regulation was plant group-reliant and guild-specific. Overall, plant responses were expressed by changes in plant cover, and not by guilds' loss. We observed (1) an increase of the guild cover of macrophytes and a decrease in bryophytes cover with increasing regulation gradient and diverse responses for riparian guilds; (2) an encroachment of riparian vegetation guilds into the channel downstream of the storage reservoir and expansion outwards downstream of the run-of-river dam; (3) a higher number of significant alterations for reservoir sites compared with run-of-river sites. Finally, for particular guilds, we determined specific DOR and DFD from which guild covers became significantly indistinct from respective guild cover in unregulated circumstances. Understanding the communities' responses to diverse regulation types and the extent that different plant adaptations may counter regulation effects can be vital for optimizing river restoration projects.
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Affiliation(s)
- Ivana Lozanovska
- Centro de Estudos Florestais, Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisboa, Portugal.
| | - Rui Rivaes
- Centro de Estudos Florestais, Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisboa, Portugal
| | - Cristiana Vieira
- Museu de História Natural e da Ciência da Universidade do Porto (MHNC-UP; UPorto/PRISC), Praça Gomes Teixeira, 4099-002 Porto, Portugal
| | - Maria Teresa Ferreira
- Centro de Estudos Florestais, Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisboa, Portugal
| | - Francisca C Aguiar
- Centro de Estudos Florestais, Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisboa, Portugal
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Benjankar R, Tranmer AW, Vidergar D, Tonina D. Riparian vegetation model to predict seedling recruitment and restoration alternatives. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2020; 276:111339. [PMID: 32920462 DOI: 10.1016/j.jenvman.2020.111339] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 08/13/2020] [Accepted: 08/31/2020] [Indexed: 06/11/2023]
Abstract
Native riparian vegetation communities have declined downstream of large water infrastructure like dams and diversions, owing to water management operations that prevent successful seedling colonization and recruitment. Altered timing and magnitude of reservoir releases to fulfill competing water demands often lead to reduced peak discharges and flow recession rates that do not support native riparian reproduction processes. To achieve short-term ecosystem function in highly regulated rivers an alternative method might be restoration planting, whereby success depends on identifying appropriate planting location and spatial extents. This study aims to provide a methodology to inform resource managers about the extent of possible natural seedling recruitment under average and wet hydrologic conditions, as well as constrain restoration planting operational uncertainties. Results from field surveys and simulations showed limited favorable areas for successful riparian seedling recruitment under regulated flows, regardless of hydrologic conditions in the basin. However, wet (11.4 ha) hydrologic conditions were more (approximately 11 times) favorable than average (1 ha) conditions for seedling recruitment. Furthermore, model results identified the location and spatial extent (25.6 ha) of favorable restoration planting areas during average flow. This extent is approximately 25 times larger than natural recruitment during an average (hydrological) year and even twice that for natural recruitment for a wet year. This suggests that ground operational activities guided by numerical modeling may effectively constrain planting uncertainties.
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Affiliation(s)
- Rohan Benjankar
- Department of Civil Engineering, Southern Illinois University Edwardsville, Edwardsville, 62026, IL, USA.
| | - Andrew W Tranmer
- Center for Ecohydraulics Research, University of Idaho, Boise, 83702, ID, USA
| | | | - Daniele Tonina
- Center for Ecohydraulics Research, University of Idaho, Boise, 83702, ID, USA
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Burrall M, DeJong JT, Martinez A, Wilson DW. Vertical pullout tests of orchard trees for bio-inspired engineering of anchorage and foundation systems. BIOINSPIRATION & BIOMIMETICS 2020; 16:016009. [PMID: 33252054 DOI: 10.1088/1748-3190/abb414] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Application of bio-inspired design in geotechnical engineering shows promise for improving the energy and material efficiency of several processes in infrastructure construction and site characterization. This project examines tree root systems for use in future bio-inspired design to improve the capacity of foundations used to support, for example, buildings and bridges. Foundation and anchorage elements used in industry are comprised almost solely of linear elements with a constant cross-sectional geometry. This functional form has remained the same for more than a century, primarily due to material availability and installation simplicity. Knowledge and understanding of the mechanisms that contribute to capacity development of natural nonlinear or branched foundation systems, such as tree root systems, could make foundation design more sustainable. The experiments described herein show that the root systems studied are 6-10 times as efficient as a conventional micropile system in developing tensile capacity on a per volume basis, with some systems displaying nearly 100 times efficiency in comparison to a conventional shallow footings. This paper explores the relationship between root system architecture and force-displacement behavior of tree root systems to better understand how to improve foundation capacity and demonstrates the potential for a more efficient use of materials and energy as compared to conventional pile and footing approaches.
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Affiliation(s)
- Matthew Burrall
- Department of Civil and Environmental Engineering, University of California Davis, 1 Shields Avenue, Davis, 95616, California, United States of America
| | - Jason T DeJong
- Department of Civil and Environmental Engineering, University of California Davis, 1 Shields Avenue, Davis, 95616, California, United States of America
| | - Alejandro Martinez
- Department of Civil and Environmental Engineering, University of California Davis, 1 Shields Avenue, Davis, 95616, California, United States of America
| | - Daniel W Wilson
- Center for Geotechnical Modeling, Department of Civil and Environmental Engineering, University of California Davis, 1 Shields Avenue, Davis, 95616, California, United States of America
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Latella M, Bertagni MB, Vezza P, Camporeale C. An Integrated Methodology to Study Riparian Vegetation Dynamics: From Field Data to Impact Modeling. JOURNAL OF ADVANCES IN MODELING EARTH SYSTEMS 2020; 12:e2020MS002094. [PMID: 32999706 PMCID: PMC7507785 DOI: 10.1029/2020ms002094] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 06/20/2020] [Accepted: 06/28/2020] [Indexed: 06/11/2023]
Abstract
Riparian environments are highly dynamic ecosystems that support biodiversity and numerous services and that are conditioned by anthropogenic activities and climate change. In this work, we propose an integrated methodology that combines different research approaches-field studies and numerical and analytical modeling-in order to calibrate an ecohydrological stochastic model for riparian vegetation. The model yields vegetation biomass statistics and requires hydrological, topographical, and biological data as input. The biological parameters, namely, the carrying capacity and the flood-related decay rate, are the target of the calibration as they are related to intrinsic features of vegetation and site-specific environmental conditions. The calibration is here performed for two bars located within the riparian zone of the Cinca River (Spain). According to our results, the flood-related decay rate has a spatial dependence that reflects the zonation of different plant species over the study site. The carrying capacity depends on the depth of the phreatic surface, and it is adequately described by a right-skewed curve. The calibrated model well reproduces the actual biogeography of the Cinca riparian zone. The overall percentage absolute difference between the real and the computed biomass amounts to 9.3% and 3.3% for the two bars. The model is further used to predict the future evolution of riparian vegetation in a climate-change scenario. The results show that the change of hydrological regime forecast by future climate projections may induce dramatic reduction of vegetation biomass and strongly modify the Cinca riparian biogeography.
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Affiliation(s)
- M. Latella
- Department of Environmental, Land and Infrastructure EngineeringPolitecnico di TorinoTurinItaly
| | - M. B. Bertagni
- Department of Environmental, Land and Infrastructure EngineeringPolitecnico di TorinoTurinItaly
| | - P. Vezza
- Department of Environmental, Land and Infrastructure EngineeringPolitecnico di TorinoTurinItaly
| | - C. Camporeale
- Department of Environmental, Land and Infrastructure EngineeringPolitecnico di TorinoTurinItaly
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Spatially explicit modelling of floodplain forest succession: interactions among flood inundation, forest successional processes, and other disturbances in the Upper Mississippi River floodplain, USA. Ecol Modell 2019. [DOI: 10.1016/j.ecolmodel.2019.05.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Plavcová L, Gallenmüller F, Morris H, Khatamirad M, Jansen S, Speck T. Mechanical properties and structure-function trade-offs in secondary xylem of young roots and stems. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:3679-3691. [PMID: 31301134 DOI: 10.1093/jxb/erz286] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Accepted: 06/27/2019] [Indexed: 05/26/2023]
Abstract
Bending and torsional properties of young roots and stems were measured in nine woody angiosperms. The variation in mechanical parameters was correlated to wood anatomical traits and analysed with respect to the other two competing functions of xylem (namely storage and hydraulics). Compared with stems, roots exhibited five times greater flexibility in bending and two times greater flexibility in torsion. Lower values of structural bending and structural torsional moduli (Estr and Gstr, respectively) of roots compared with stems were associated with the presence of thicker bark and a greater size of xylem cells. Across species, Estr and Gstr were correlated with wood density, which was mainly driven by the wall thickness to lumen area ratio of fibres. Higher fractions of parenchyma did not translate directly into a lower wood density and reduced mechanical stiffness in spite of parenchyma cells having thinner, and in some cases less lignified, cell walls than fibres. The presence of wide, partially non-lignified rays contributed to low values of Estr and Gstr in Clematis vitalba. Overall, our results demonstrate that higher demands for mechanical stability in self-supporting stems put a major constraint on xylem structure, whereas root xylem can be designed with a greater emphasis on both storage and hydraulic functions.
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Affiliation(s)
- Lenka Plavcová
- University of Hradec Králové, Department of Biology, Faculty of Science, Rokitanského, Hradec Králové, Czech Republic
| | - Friederike Gallenmüller
- Plant Biomechanics Group Freiburg, Botanic Garden of the Albert-Ludwigs-University of Freiburg, Faculty of Biology, Schänzlestrasse, Freiburg, Germany
| | - Hugh Morris
- Laboratory for Applied Wood Materials, Empa - Swiss Federal Laboratories for Materials Testing and Research, St Gallen, Switzerland
| | - Mohammad Khatamirad
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee, Ulm, Germany
| | - Steven Jansen
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee, Ulm, Germany
| | - Thomas Speck
- Plant Biomechanics Group Freiburg, Botanic Garden of the Albert-Ludwigs-University of Freiburg, Faculty of Biology, Schänzlestrasse, Freiburg, Germany
- Cluster of Excellence livMatS @ FIT - Freiburg Center for Interactive Materials and Bioinspired Technologies, Freiburg, Germany
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Lavaine C, Evette A, Piégay H. European Tamaricaceae in bioengineering on dry soils. ENVIRONMENTAL MANAGEMENT 2015; 56:221-232. [PMID: 25896819 DOI: 10.1007/s00267-015-0499-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Accepted: 04/10/2015] [Indexed: 06/04/2023]
Abstract
We tested the bioengineering capabilities and resistance to drought of cuttings of two typical riparian species of Mediterranean and Alpine streams scarcely used in soil bioengineering: Myricaria germanica (L.) Desv. and Tamarix gallica L. We conducted two experiments, one ex situ and one in situ, with different drought treatments on cuttings of these two species in comparison with Salix purpurea L., a willow very commonly used in bioengineering. The biological traits considered were resprouting/survival rate, quantity of structural roots, above- and belowground biomass, shoot-to-root ratio, and ratio of the biomass increase between the first and second season. T. gallica and M. Germanica showed generally good capabilities for soil bioengineering use. T. gallica showed especially good resprouting rates in drought conditions with a survival rate of 97% in dry modality of the in situ experiment. M. germanica cuttings presented a much lower survival rate than the other two species in in situ experiments with harsh drought conditions from the beginning. T. gallica had a lower shoot-to-root ratio than S. purpurea for all drought treatments. M. germanica and T. gallica showed a very significant increase in belowground biomass during the second vegetative period, demonstrating that these species can quickly achieve strong anchoring. These observations confirmed the interest of these species in bioengineering.
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Affiliation(s)
- Catherine Lavaine
- Irstea, UR EMGR, Centre de Grenoble, 2 rue de la Papeterie-BP 76, 38402, St-Martin-d'Hères, France
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Chimungu JG, Loades KW, Lynch JP. Root anatomical phenes predict root penetration ability and biomechanical properties in maize (Zea Mays). JOURNAL OF EXPERIMENTAL BOTANY 2015; 66:3151-62. [PMID: 25903914 PMCID: PMC4449537 DOI: 10.1093/jxb/erv121] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
The ability of roots to penetrate hard soil is important for crop productivity but specific root phenes contributing to this ability are poorly understood. Root penetrability and biomechanical properties are likely to vary in the root system dependent on anatomical structure. No information is available to date on the influence of root anatomical phenes on root penetrability and biomechanics. Root penetration ability was evaluated using a wax layer system. Root tensile and bending strength were evaluated in plant roots grown in the greenhouse and in the field. Root anatomical phenes were found to be better predictors of root penetrability than root diameter per se and associated with smaller distal cortical region cell size. Smaller outer cortical region cells play an important role in stabilizing the root against ovalization and reducing the risk of local buckling and collapse during penetration, thereby increasing root penetration of hard layers. The use of stele diameter was found to be a better predictor of root tensile strength than root diameter. Cortical thickness, cortical cell count, cortical cell wall area and distal cortical cell size were stronger predictors of root bend strength than root diameter. Our results indicate that root anatomical phenes are important predictors for root penetrability of high-strength layers and root biomechanical properties.
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Affiliation(s)
- Joseph G Chimungu
- Department of Plant Science, The Pennsylvania State University, University Park, PA 16802, USA
| | | | - Jonathan P Lynch
- Department of Plant Science, The Pennsylvania State University, University Park, PA 16802, USA
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Chamaillard S, Fichot R, Vincent-Barbaroux C, Bastien C, Depierreux C, Dreyer E, Villar M, Brignolas F. Variations in bulk leaf carbon isotope discrimination, growth and related leaf traits among three Populus nigra L. populations. TREE PHYSIOLOGY 2011; 31:1076-87. [PMID: 21990023 DOI: 10.1093/treephys/tpr089] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
The ongoing global change could be an additional threat to the establishment and the long-term survival of Populus nigra L., an emblematic European riparian species. With the general aim of gaining insights into the adaptive potential of this species, we (i) quantified variations within and among three French P. nigra populations for key physiological attributes, i.e., water-use efficiency (assessed from bulk leaf carbon isotope discrimination, Δ(13)C), growth performance and related leaf traits, (ii) examined genotype and population by environment interactions, and (iii) explored the relationship between Δ(13)C and growth. Thirty genotypes were sampled in each of three naturally established populations and grown in two different sites, Orléans (ORL) and Guémené-Penfao (GMN). In ORL, two similar plots were established and different watering regimes were applied in order to test for the drought response. Significant variations were observed for all traits within and among populations irrespective of site and watering. Trait variation was larger within than among populations. The effect of drought was neither genotype- nor population-dependent, contrary to the effect of site. The population ranking was maintained in all sites and watering regimes for the two most complex traits: Δ(13)C and growth. Moreover, these two traits were unrelated, which indicates that (i) water-use efficiency and growth are largely uncoupled in this species, and (ii) the environmental factors driving genetic structuration for Δ(13)C and growth act independently. The large variations found within populations combined with the consistent differences among populations suggest a large adaptive potential for P. nigra.
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Affiliation(s)
- Sylvain Chamaillard
- UFR-Faculté des Sciences, UPRES EA 1207 'Laboratoire de Biologie des Ligneux et des Grandes Cultures' (LBLGC), Université d'Orléans, rue de Chartres, BP 6759, F-45067 Orléans Cedex 2, France
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Samarakoon MB, Tanaka N, Yagisawa J. Effects of local scouring and saturation of soil due to flooding on maximum resistive bending moment for overturning Robinia pseudoacacia. LANDSCAPE AND ECOLOGICAL ENGINEERING 2011. [DOI: 10.1007/s11355-011-0169-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Saccone P, Pagès JP, Girel J, Brun JJ, Michalet R. Acer negundo invasion along a successional gradient: early direct facilitation by native pioneers and late indirect facilitation by conspecifics. THE NEW PHYTOLOGIST 2010; 187:831-842. [PMID: 20487316 DOI: 10.1111/j.1469-8137.2010.03289.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
*Here, we analysed the role of direct and indirect plant interactions in the invasion process of Acer negundo along a natural successional gradient in the Middle Rhone floodplain (France). We addressed two questions: What are the responses of the invasive Acer seedlings to native communities' effects along the successional gradient? What are the effects of the invasive Acer adult trees on the native communities? *In the three communities (Salix, Acer and Fraxinus stands) we transplanted juveniles of the invasive and juveniles of the natives within the forest and in experimental gaps, and with and without the herb layer. We also quantified changes in understory functional composition, light, nitrogen and moisture among treatments. *Acer seedlings were directly facilitated for survival in the Salix and Acer communities and indirectly facilitated for growth by adult Acer through the reduction of the abundance of highly competitive herbaceous competitors. *We conclude that direct facilitation by the tree canopy of the native pioneer Salix is very likely the main biotic process that induced colonization of the invasive Acer in the floodplain and that indirect facilitation by adult conspecifics contributed to population establishment.
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Affiliation(s)
- Patrick Saccone
- Cemagref-Unité de Recherche Ecosystèmes Montagnards, St-Martin-d'Heres, France
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Stokes A, Lucas A, Jouneau L. Plant biomechanical strategies in response to frequent disturbance: uprooting of Phyllostachys nidularia (Poaceae) growing on landslide-prone slopes in Sichuan, China. AMERICAN JOURNAL OF BOTANY 2007; 94:1129-1136. [PMID: 21636480 DOI: 10.3732/ajb.94.7.1129] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Bamboo is considered useful for controlling landslides, but we observed numerous shallow-slope failures in forests of big node bamboo (Phyllostachys nidularia) in Sichuan, China. Therefore, we inventoried landslide occurrence and vegetation type along one valley. To quantify bamboo root anchorage, we performed uprooting tests and measured plant morphological characteristics. Landslide occurrence was greatest at sites with bamboo and young trees. Culm failure was common because of the high length to diameter ratio (242 ± 6). Uprooting tests showed that the maximal force to cause failure was small (1615 ± 195 N). Uprooting force was strongly and positively regressed with a combination of the predictors lateral root number and volume (R(2) = 0.92), and root systems were highly superficial (depth = 0.15 ± 0.12 m), contributing little to slope stability. In P. nidularia, which grows on landslide-prone slopes, surprisingly few resources have been allocated to anchorage. We suggest that this strategy puts this pioneer at an advantage on steep slopes, where it contributes little to slope stability and colonizes frequently formed gaps through vegetative regeneration. Fewer disturbances would result in subsequent secondary succession and dying back of this shade intolerant species.
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Affiliation(s)
- Alexia Stokes
- Institut National de la Recherche Agronomique (INRA), Laboratoire Franco-Chinois d'Informatique, d'Automatique et de Mathématiques Appliquées (LIAMA), Chinese Academy of Sciences-Institute of Automation (CASIA), P.O. Box 2728, Haidian District, 100080 Beijing, China
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