Growth Characteristics and Anti-Wind Erosion Ability of Three Tropical Foredune Pioneer Species for Sand Dune Stabilization

Abstract

Rainstorms frequently cause runoff and then the runoff carries large amounts of sediments (sand, clay, and silt) from upstream and deposit them on different landforms (coast, plain, lowland, piedmont, etc.). Afterwards, monsoons and tropical cyclones often induce severe coastal erosion and dust storms in Taiwan. Ipomoea pes-caprae (a vine), Spinifex littoreus (a grass), and Vitex rotundifolia (a shrub) are indigenous foredune pioneer species. These species have the potential to restore coastal dune vegetation by controlling sand erosion and stabilizing sand dunes. However, their growth characteristics, root biomechanical traits, and anti-wind erosion abilities in sand dune environments have not been documented. In this study, the root growth characteristics of these species were examined by careful hand digging. Uprooting test and root tensile test were carried out to measure their mechanical strength, and wind tunnel (6 m × 1 m × 1.3 m, L × W × H) tests were executed to explore the anti-wind erosion ability using one-year-old seedlings. The results of root growth characteristics demonstrate that I. pes-caprae is superior to S. littoreus and V. rotundifolia. Moreover, uprooting resistance of V. rotundifolia seedlings (0.074 ± 0.032 kN) was significantly higher than that of I. pes-caprae (0.039 ± 0.015 kN) and S. littoreus (0.013 ± 0.005 kN). Root tensile strength of S. littoreus (16.68 ± 8.88 MPa) and V. rotundifolia (16.48 ± 4.37 MPa) were significantly higher than that of I. pes-caprae (6.65 ± 2.39 MPa). In addition, wind tunnel tests reveal that sand wind erosion rates for all three species decrease with increasing vegetation cover, but the anti-wind erosion ability of S. littoreus seedlings is significantly higher than I. pes-caprae and V. rotundifolia. Results of root tensile strength and anti-wind erosion ability clearly show that S. littoreus is superior to I. pes-caprae and V. rotundifolia. Taken together, our results suggest that I. pes-caprae and S. littoreus are beneficial for front line mixed planting, while V. rotundifolia is suitable for second line planting in foredune areas. These findings, along with the knowledge on adaption of foredune plants following sand accretion and erosion, provide us critical information for developing the planting strategy of foredune pioneer plants for the sustainable management of coastal foredune ecosystem.

Root Functional Traits and Water Erosion-Reducing Potential of Two Indigenous C4 Grass Species for Erosion Control of Mudstone Badlands in Taiwan

“…Statistical data demonstrated that the maximal root pullout resistance of C. dactylon is remarkably higher than that of E. ophiuroides. Earlier studies also demonstrated positive relations between pullout resistance, root biomass, architecture, and root surface area [30,39,43]. Clearly, C. dactylon with more profuse fibrous roots, root biomass and total root surface has higher pullout resistance than E. ophiuroides.…”

“…Root surface area and length were evaluated utilizing WinRHIZO software (Regent Inc., Quebec, QC, Canada) [28], while root volume was estimated using water displacement technique [29]. Root dry unit weight was also measured [30]. These figures were used to determine root traits.…”

Impact of landscape patterns on herb-layer diversity and seed size of Schima superba in urban remnant vegetation: A case study in Guangzhou, Southern China

“…But for the urban remnant vegetation, especially the herb-layer plant with high urban disturbance, are more necessary to study how they can survive. Pioneer plants, for example, are hardy species that are the first to colonize previously disrupted or damaged ecosystems (Lee et al 2020). In urban, Pioneer plants, mainly weeds and annual herbaceous plants, are often able to withstand high air pollution, trampling, alkaline, compacted, and nitrogen-rich soils those are generated by the high degree of urbanization (McKinney 2006), so they are easily replaced by late-successional species in the later period.…”

Root Traits and Erosion Resistance of Three Endemic Grasses for Estuarine Sand Drift Control

“…In northern Bangladesh, traditional erosion management approaches have been applied to control riverbank erosion and enhance livelihood resilience [10]. The estuarine vegetation is very efficient at trapping drifting sand and reducing aeolian erosion [11], and its use is regarded as an effective ecological engineering method for sand drift control [12,13].…”

“…Hamidifar et al [24] demonstrated that vetiver grass (Vetiveria zizanioides L.) can increase soil cohesion and the soil internal friction factor and enhance riverbank shear strength. Several studies revealed that plant coverage can notably decrease the wind erosion rate [13,25]. However, the root traits, mechanical properties and wind erosion resistance of A. formosana, P. australis and S. spontaneum have not been explored.…”