Effects of soil compaction on seedling morphology, growth, and architecture of chestnut-leaved oak (Quercus castaneifolia)

Abstract

Soil compaction following traffic by heavy-timber harvesting machinery usually causes an increase in soil strength, that is a stress factor negatively affecting the growth of newly germinated seedlings. This study used a soil strength experiment carried out in a greenhouse to test the hypotheses that increasing soil strength would adversely affect seedling morphology and alter seedling architecture by changing biomass allocation patterns. We explored the effects of soil compaction in a loam to clay-loam textured soil with optimal conditions of water on a continuous scale (0.2-1.0 MPa penetration resistance) on growth responses of the deciduous Quercus castaneifolia (C.A.Mey). Both above-and below-ground seedling characteristics, including size and biomass, were negatively affected by soil compaction. At the highest intensity of compaction, size and growth were reduced by 50% compared to controls; negative effects were typically more severe on below-ground (i.e., the length and biomass of the root system) than on above-ground responses. Increasing soil strength did not change above-and below-ground biomass allocation patterns (i.e., root mass ratio, root:shoot ratio, specific root length), resulting in unchanged seedling architecture. Strong adverse effects were already evident in the low-intensity compaction treatment and no critical soil strength threshold was observed. We conclude that root and height growth in Q. castaneifolia seedlings is limited by any increase of soil strength, though no evidence for the disruption of a functional equilibrium between above-and below-ground plant portions was found up to soil strengths of 1.0 MPa, at least under optimal water supply.

Mechanical Characteristics of the Fine Roots of Two Broadleaved Tree Species from the Temperate Caspian Hyrcanian Ecoregion

“…[72]. Goodman and Ennos [73] demonstrated, however, that the roots of two annual plants, Zea mays L. and Helianthus annuus L., either became stiffer or were unchanged, respectively, when growing in soil with low bulk density Moreover, Jourgholami et al [74] investigated the ratio of lateral to main root length, which is significantly reduced in high intensity compaction in comparison with control treatment, although the ratio of lateral to main root biomass was not significant among different soil compaction treatments. Accordingly, to prove if soil physical characteristics affect root resistance and mechanical properties, further studies are required.…”

Characteristics of physical properties in soil profiles under selected introduced trees in the Nature Reserve Arboretum Mlyňany, Slovakia

“…Moreover, Dexter (2004) stated that soil compaction has negative effect on plant root growth through reducing the storage and supply of water and nutrients. Consequently, it causes decreased growth (biomass) responses of the whole plant and of the plant´s components such as stem, shoot, leaves, roots (Jourgholami et al, 2016). Adverse effect of soil compaction mainly occurs through increasing soil bulk density and soil strength, decreasing macro porosity, soil water infiltration and water-holding capacity, what may negatively influence soil biological properties (Frey et al, 2009).…”

Effect of Soil Compaction on the Growth and Nutrient Uptake of Zea Mays L.

“…When soil are compacted, the bulk density is increased and the pore spaces reduces, therefore plant roots have to develop a higher force necessary to displace the compacted soil particles which consequently limits root growth. The negative impact of soil compaction on root growth observed in this study can be due to limited availability of water and nutrients for satisfactory plant growth and yield (Chen et al, 2014 andJourgholami et al, 2016). Figure 5.…”

“…The unfavourable soil conditions created by increasing soil compaction (soil penetration resistance) observed in this study could account for the recorded reduction in mineral uptake. The ability of plants to absorb nutrients from the soil is essentially related to their ability to develop extensive roots systems (Jourgholami et al, 2016). Figure 6.…”

“…Change in bulk density, shear and penetration resistance are some factors caused by compaction which affects plants root growth (Taylor and Gardner, 1963;Grzesiak et al, 2013;Cambi et al, 2015). Soil compaction can influence the concentration and movement of water, oxygen and carbon dioxide which could result in a restricted root development root (Taylor and Brar, 1991;Jourgholami et al, 2016). Guan et al (2014) stated that one of the function of plant roots is to maintain the supply of nutrients and water to the plant while the yield is dependent on the root development in the soil profile which determines the capacity for nutrient uptake and water extraction by plants.…”