Effects of increased precipitation on the life history of spring- and autumn-germinated plants of the cold desert annual Erodium oxyrhynchum (Geraniaceae)

Abstract

Future increased precipitation in cold desert ecosystems may impact annual/ephemeral plant species that germinate in both spring and autumn. Our primary aim was to compare the life history characteristics of plants from spring-germinating (SG) and autumn-germinating (AG) seeds of Erodium oxyrhynchum. Plants in field plots with simulated increases in precipitation of 0, 30 and 50 % in spring and summer were monitored to determine seedling survival, phenology, plant size, seed production and biomass accumulation and allocation. Germination characteristics were determined in the laboratory for seeds produced by plants in all increased precipitation treatments. Increased precipitation in spring significantly improved survival of seedlings from SG and AG seeds, but survival was less for AG than SG. An increase in precipitation increased the number of seeds per plant for both SG and AG, but AG produced more seeds per plant than SG. With increased precipitation, percentage of dormant seeds from SG increased significantly, while that of AG decreased slightly. Our study suggests that with increased spring and summer rainfall AG will produce an increased number of nondormant seeds that could germinate in autumn and SG an increased number of dormant seeds that become part of the soil seed bank. However, ability of some seeds to germinate in autumn and others in spring will be maintained as long as soil moisture is limited in autumn.

Life history response of Echinops gmelinii Turcz. to variation in the rainfall pattern in a temperate desert

“…Similarly, some water manipulation experiments in arid and semiarid ecosystems showed that reductions in the amount of rainfall usually limit plant growth and/or seed production, whereas an increased water supply has the opposite effect (Breen & Richards, 2008; Volis, Ormanbekova & Yermekbayev, 2015; Mojzes et al, 2018). The response of E. gmelinii root/shoot ratio to rainfall amount was consistent with that of plants growing in arid regions, in which increased allocation to roots may be advantageous for capturing limiting soil resources (Padilla et al, 2013; Gao et al, 2015; Shan et al, 2018; Chen et al, 2019a). Moreover, under high amounts of rainfall (150% and 125%), plant growth and reproductive traits under the rainfall frequency of 10-day interval were significantly higher than those observed in association with other frequencies (Figs.…”

Versatility in the timing of seed germination of the cold desert herbaceous perennialLeontice incerta(Berberidaceae)

“…Thus, by early spring of the next year when the soil is wet due to snow melt and low soil temperatures are suitable for germination, seeds can germinate rapidly and to high percentages. These patterns were also reported in other cold desert species such as Eremopyrum distans (Wang et al, 2010a), Isatis violascens (Zhou et al, 2015) and Erodium oxyrhynchum (Chen et al, 2019a,b). By late March of the next year, seedlings emerge and grow rapidly when soil temperatures start rising again, and rain is available.…”

“…Although herbaceous perennials are an important component of the cold desert vegetation of Central Asia (Tang et al, 2009; Sharma and Sharma; 2010; Baskin and Baskin, 2014), their seed germination ecophysiology has received relatively little research attention (Tang et al, 2009; Fu et al, 2013; Mamut et al, 2014b). On the other hand, much research has been done on the germination of cold desert annuals of Central Asia (Sun et al, 2009; Lu et al, 2010, 2015; Ma et al, 2010; Tang et al, 2010; Wang et al, 2010a; Mamut et al, 2014a; Zhou et al, 2015; Chen et al, 2019a,b). For various species of annuals, rainfall in autumn promotes the germination of some seeds in a given cohort (i.e.…”

“…seeds produced at the same time/season), resulting in seedlings that may survive overwinter and plants that flower in next spring. However, after snow melt in next spring additional seeds from the same seed cohort germinate, and these plants, as well as those from autumn-germinated seeds, flower and set seeds before the onset of high summer temperatures and periods of drought (see Chen et al, 2019a,b).…”

Peer Review #1 of "Life history response of Echinops gmelinii Turcz. to variation in the rainfall pattern in a temperate desert (v0.1)"

“…Similarly, some water manipulation experiments in arid and semiarid ecosystems showed that reductions in the amount of rainfall usually limit plant growth and/or seed production, whereas an increased water supply has the opposite effect (Breen and Richards 2008, Volis et al 2015, Mojzes et al 2018. The response of E. gmelinii root/shoot ratio to rainfall amount was consistent with that of plants growing in arid regions, in which increased allocation to roots may be advantageous for capturing limiting soil resources (Padilla et al 2013, Gao et al 2015, Shan et al 2018, Chen et al 2019a. Moreover, under high amounts of rainfall (150% and 125%), plant growth and reproductive traits under the rainfall frequency of 10-day interval were significantly higher than those observed in association with other frequencies (Fig.…”