Population Dynamics and Life History Response to Precipitation Changes for a Desert Ephemeral Plant With Biseasonal Germination

Abstract

The changing availability of water resources and frequent extreme drought events in the context of global change will have a profound impact on desert vegetation, especially on herbaceous populations such as ephemerals. Erodium oxyrrhynchum is the dominant species in the Gurbantunggut Desert. It can germinate both in spring and autumn, which is important for herbaceous layer coverage and productivity. Therefore, we tracked and recorded the survival and reproduction of the E. oxyrrhynchum population under different precipitation treatments and established a population matrix model, monitored the allometry and leaf traits of the plants, and compared the performance of spring-germinating and autumn-germinating plants. Our results showed that: (1) The population dynamics were significantly affected by precipitation changes; (2) drought reduced the survival rate of the plants and accelerated the completion of their life history; (3) precipitation had a significant effect on seed production and growth rate, but not on plant height and allometry; (4) biomass, leaf area, specific leaf area, and 100-grain weight of E. oxyrrhynchum also responded to changes in precipitation; and (5) autumn-germinated plants had higher productivity, whereas spring-germinated plants exhibited higher reproductive efficiency, indicating that they had difference life history strategies. In conclusion, our results suggested that, although frequent or prolonged drought can significantly inhibit population growth, species with biseasonal germination are likely to be less affected.

Is the Life History Flexibility of Cold Desert Annuals Broad Enough to Cope with Predicted Climate Change? The Case of Erodium oxyrhinchum in Central Asia

“…However, in dry springs, the number of seeds that germinates and number of seeds SG plants produced decreased. In dry springs, many SG plants died due to low soil moisture (also see [ 36 ]), and plants were small with low seed production. On the other hand, if a wet autumn is followed by a dry spring, AG plants can use the limited soil moisture and produce a large number of seeds.…”

“…E. oxyrhinchum seeds have physical dormancy, and dormancy release needed high temperature in summer and low temperature in autumn and winter. However, seeds can germinate in autumn if the soil is moist [ 12 , 35 , 36 ]. Spring-germinated (SG) plants complete their ephemeral life cycle in about 2 months.…”

“…Spring-germinated (SG) plants complete their ephemeral life cycle in about 2 months. Autumn- germinated (AG) plants overwinter as rosettes and complete their (winter annual) life cycle the following spring [ 22 , 36 ]. The seeds from both SG and AG plants of E. oxyrhinchum have physical dormancy (PY), but the percentage of seeds with PY (vs. those with nondormancy) differed significantly [ 37 ].…”

Impact of groundwater depth on hydraulic performance and growth of Haloxylon ammodendron in a desert region of central Asia

“…H. ammodendron was the most abundant species in the community accompanied by 40 species of ephemeral plants in the study area. Most of the ephemerals were members of the Brassicaceae and Asteraceae, while the most common species were Erodium oxyrrhynchum , Alyssum linifolium , Malcolmia scorpioides and Hyalea pulchella (Mu et al, 2021). The location coordinates of the sampling site is shown in Table 1.…”

Effect of Nutrient Addition on the Productivity and Species Richness of Grassland Along With an Elevational Gradient in Tajikistan

“…Productivity and diversity are two major properties of ecosystems and environmental factors can affect the productivity; the variation will lead to the change of diversity simultaneously and vice versa (Gross and Cardinale, 2007;Wang et al, 2019). In arid areas, water largely determines the plant growth, thus competition among plants is mainly access to water resources (Mu et al, 2021). When precipitation increases, the rapid growth of some species will further lead to the competition for light, which may lead to the decrease in diversity.…”