The ecological role of dew in assisting seed germination of the annual desert plant species in a desert environment, northwestern China

Abstract

It is important to understand the effects of dew events on non-mucilaginous seed germination of annual desert plant species during dry seasons, which is critical to maintaining long-term soil seed banks in a harsh desert environment. We hypothesize that dew deposition also assists in the non-mucilaginous seed germination of annual desert species. A common field dew treatment experiment was conducted in the Linze Inland River Basin Research Station to investigate the effects of dew deposition on the seed germination of four annual species, including Agriophyllum squarrosum, Corispermum mongolicum, Bassia dasyphylla and Halogeton arachnoideus. The results showed that the presence of dew significantly increased seed germination percentages and decreased the nonviable seed percentages of B. dasyphylla and H. arachnoideus, whereas there was no such trend for the seeds of C. mongolicum and A. squarrosum. The ecological effects of dew on the seed germination and viability of the annual desert plants were species specific. Although dew wetting is insufficient to cause seed germination, it may help in priming the seeds.

Measurements and ecological implications of non‐rainfall water in desert ecosystems—A review

“…Among the positive roles played by dew and fog are also an increase in the relative water content of the leaves (Gouvre & Grammatikopoulos, 2003), branches (Hill et al, 2015;Yates & Hutley, 1995), and the xylem water potential (Berry & Smith, 2013;Kim & Lee, 2011), all of which assist in chlorophyll and carotenoid recovery . Additionally, dew and fog may reduce wilting and increase survival probabilities during water stress (Babu & Went, 1978;Cosh et al, 2009;Duvdevani, 1957), improve the recovery of DNA damage of seeds (Gutterman & Shem-Tov, 1997;Yang, Zhang, Dong, Boubriak, & Huang, 2011;Zhuang & Zhao, 2016) and germination (Yang et al, 2011;Yang, Bu, Mu, Shao, & Zhang, 2014;Zhuang & Zhao, 2016), and increase plant growth, yield, and biomass (Boucher et al, 1995;Duvdevani, 1957;Duvdevani, Reichert, & Palti, 1946;Zhuang & Ratcliffe, 2012). Although some researchers report on dew utilization by roots (Pan et al, 2010) or on the use of vapour absorption by roots (Kosmas et al, 2001;Ramírez, Bellot, Domingo, & Blasco, 2007), these claims were not yet substantiated and require further research.…”

Experimental variations in functional and demographic traits of Lappula semiglabra among dew amount treatments in an arid region

“…These results suggested that dew affected the demographic traits of L. semiglabra . Additionally, in order to utilise the sustainable water resources, most of ephemeral plants germinated in the snow melting period in spring in arid desert (Mckenna & Houle, ; Zhuang & Zhao, ). Due to the continuous water consumption by evaporation and plant absorption, the amount of snow meltwater decreased gradually along the plant growth season (Hill et al, ; Mao & Zhang, ; Steyn et al, ).…”

“…Dew, as an important input of water resources in a desert area, is condensed water of air moisture generated in near‐surface air at the temperature lower than the dew point temperature (Fischer, Veste, Bens, & Hüttl, ; Jacobs, Heusinkveld, & Berkowicz, ; Mchugh et al, ; Tomaszkiewicz, Najm, Beysens, Alameddine, & Elfadel, ). Therefore, the amount of dew has been anticipated to affect several ecological processes and functions including dune stability, biological soil crust, seed germination, plant survival, and biodiversity (Ben‐Asher, Alpert, & Ben‐Zvi, ; Hanisch, Lohrey, & Buerkert, ; Hill et al, ; Ratcliffe, ; Tomaszkiewicz et al, ; Zhuang & Zhao, ). However, our understandings whether and how amounts of dew affect variations in functional traits and demographic traits, which are potential indicators or factors for biodiversity and life history of a plant, remain unclear.…”

“…. Therefore, the amount of dew has been anticipated to affect several ecological processes and functions including dune stability, biological soil crust, seed germination, plant survival, and biodiversity (Ben-Asher, Alpert, & Ben-Zvi, 2010;Hanisch, Lohrey, & Buerkert, 2015;Hill et al, 2015;Ratcliffe, 2012;Tomaszkiewicz et al, 2015;Zhuang & Zhao, 2016). However, our understandings whether and how amounts of dew affect variations in functional traits and demographic traits, which are potential indicators or factors for biodiversity and life history of a plant, remain unclear.…”

“…The higher diurnal temperature difference and near-surface air moisture is conducive to the deposition of dew (Beysens, 1995;Garratt & Segal, 1988). In arid deserts, low heat capacity of sandy soil causes the diurnal temperature difference in the near-surface layer, thus leading to the deposition of a small amount of dew (Delgado-Baquerizo, Maestre, Rodríguez, & Gallardo, 2013;Hanisch et al, 2015;Heusinkveld, Jacobs, & Berkowicz, 1998;Hill et al, 2015;Jacobs, Heusinkveld, & Berkowicz, 2000;Zhuang & Zhao, 2016). Most of the previous studies indicated that the trace dew has little positive impact on the functions of plants because the water supply is offset by high evaporation in arid desert (Agam & Berliner, 1963;Burgess & Dawson, 2004;Fischer et al, 2012;Hao et al, 2012;Heusinkveld et al, 1998).…”