Foliar traits of Juglans regia, Aesculus hippocastanum and Tilia platyphyllos in urban hábitat
Juglans regia, Aesculus hippocastanum and Tilia platyphyllos species are widely used for planting. In the present study, two extremes of spring and autumn were chosen as sampling seasons. Leaf traits included in this analysis are: leaf relative water content (LRWC), specific leaf area (SLA), density of foliar tissue (D), leaf ash content (LAC). Those parameters are easily and rapidly screened, and relatively inexpensive. Relationships between different parameters were examined with Pearson’s correlation analyses and and t-test. Results on relative water content recorded in leaves showed high variations at various stages. The results of the present study also revealed significant seasonal variability in mineral content composition. The other leaf physiological parameters differed significantly.
Keywords: leaf parameters, developmental stage, urban hábitat
More information: https://www.rombio.eu/vol22nr2/—-13_Ianovici_final.pdf
Impact of Tilia platyphyllos Scop., Fraxinus excelsior L., Acer pseudoplatanus L., Quercus robur L. and Fagus sylvatica L. on earthworm biomass and physico-chemical properties of a loamy topsoil
Impact of hardwoods of different humus forms on earthworm biomass and physico-chemical properties of the topsoil of a loamy acid brown forest soil after a time-span of 60–65 years was examined in the Forest of Halle near Brussels. Three sites were selected in which homogeneous stands of mull-forming tree species (Tilia platyphyllos Scop., Fraxinus excelsior L. and Acer pseudoplatanus L.) were compared with adjacent stands of Fagus sylvatica L. and/or Quercus robur L. where a mullmoder had developed. Total earthworm biomass was conspicuously higher at the sites that supported Tilia and Acer as mull-forming hardwoods. Study of soil acidity revealed that there were marked differences in pH and base saturation in the A- and E-horizon between hardwoods developing different humus forms. The topsoil beneath mull-forming hardwoods was generally higher in pH and base saturation with the largest differences being displayed between Tilia and Fagus/Quercus. C/N ratios were significantly lower in the topsoil under Acer. Significant differences in physical soil properties among humus form were also evident. The A-horizon under mull-forming species was higher in total porosity, aeration porosity and saturated hydraulic conductivity. The bulk density was only significantly lower under Fraxinus. The E-horizon of the mull stands was lower in bulk density and higher in aeration porosity but this was linked by a reduction in water-filled porosity. The study indicated that mull-forming tree species differed in ability to improve or maintain productivity of the studied soil type.
More information: https://www.sciencedirect.com/science/article/pii/S0378112799002406