found to reduce bulk density and increase air-filled porosity in substrates for turfgrass growth ( Nektarios et al., 2003a ), in potted plants ( Chan and Joyce, 2007 ; Nguyen et al., 2009 ), and in green roof substrates ( Nektarios et al., 2003b ). In
boxwood and 1.6 d in deutzia. This contrasts with the daily irrigation event that occurs with DWU. A set point-based irrigation can allow optimization of both air-filled porosity and water potential of the substrate, maximizing plant growth ( Welsh and
organic substrates, on average, had 85.2% and 85.0% total porosity, 21.6% and 35.9% air-filled porosity, 63.6% and 49.1% water-holding capacity, and 0.19 and 0.097 g·cm –3 bulk density, as analyzed using the North Carolina State University porometer
significantly less water ( P = 0.0002) than the peat-based media; however, peat substrates are inherently fibrous and have increased microporosity, which resulted in lower air-filled porosity values than bark ( P = 0.0002; Table 1 ). Altland et al. (2011
.-E. Rioux, J.-A. 1996 Air-filled porosity, gas relative diffusivity, and tortuosity: Indices of Prunus x cistena sp. growth in peat substrates J. Amer. Soc. Hort. Sci. 121 236 242 Bilderback, T. 1999 Potting mix choices and recommendations Proc. North
by Wang et al. (2012) . Substrate characterization. Air-filled porosity (AFP) and water-holding capacity (WHC) of the substrates were measured using a modified version of the Australian Standards method for potting mixes (AS 3743–2003; appendix B
other common greenhouse rose rootstocks ( de Hoog, 2001 ; de Vries, 2003 ; Safi, 2005 ), is not observed under even moderate salt stress levels. Other abiotic stresses like poor air-filled porosity (i.e., poor soil aeration) have been shown to
Proc. 7th Intl. Congr. Soilless Culture, ISOSC Wageningen, The Netherlands Allaire, S.E. Caron, J. Duchesne, I. Parent, L.-E. Rioux, J.-A. 1996 Air-filled porosity, gas relative diffusivity and
.2% air-filled porosity, 0.93 g·cm −2 dry bulk density, electrical conductivity (EC) of 761 μS·cm −1 , and pH of 6.5], which was held in the trays by white plastic raisers. The substrate had a 42% volumetric water content, 0.013 cm·s −1 permeability
measurements: Theory and practice Adv. Irr. 1 25 42 Caron, J. Pepin, S. Periard, Y. 2014 Physics of growing media in a green future Acta Hort. 1034 309 317 Caron, J. Riviere, L.M. Guillemain, G. 2005 Gas diffusion and air-filled porosity: Effect of some