Seasonal variability of groundwater level effects on the growth of Carex cinerascens in lake wetlands

Abstract

Groundwater level is crucial for wetland plant growth and reproduction, but the extent of its effect on plant growth can vary along with changed precipitation and temperature at different seasons. In this context, we investigated the effect of two groundwater levels (10 cm vs. 20 cm depth) on growth and reproductive parameters of Carex cinerascens, a dominant plant species in the Poyang Lake wetland, during three seasons (spring, summer, and autumn) and during two consecutive years (2015 and 2016). Carex cinerascens showed low stem number, height, and individual and population biomass in summer compared to spring and autumn. 10 cm groundwater level was overall more suitable for plant growth resulting in higher stem height and biomass. However, the interactive effect between groundwater level and season clearly demonstrated that the effect of groundwater level on plant growth occurred mainly in autumn. After the withering of the plant population in summer, we observed that C. cinerascens growth recovered in autumn to similar values observed in spring only with 10 cm groundwater level. Consequently, we could deduce that lowering groundwater level in the studied Poyang Lake wetland will negatively impact C. cinerascens regeneration and growth particularly during the second growth cycle occurring in autumn. Additionally, our results showed that, independently of the season and groundwater level, population biomass of C. cinerascens was lower during drier year. Altogether, our findings suggest that water limitation due to both reduction in precipitation and decreased groundwater level during the year can strongly impact plant communities.

Associations of soil bacterial diversity and function with plant diversity in Carex tussock wetland

“…In these quadrats, the plant species and quantity of companion species decreased. Water is a key driver of plant diversity and community structure in wetland ecosystems, and it can change the vegetation and biomass ( Li et al, 2015 ; Feng et al, 2020 ; Shan et al, 2020 ). In particular, in Carex tussock wetland, the growth and physiology of plants and species diversity respond to water level fluctuations ( Wang et al, 2016 ; Zhang et al, 2020 ).…”

Winter coexistence in herbivorous waterbirds: Niche differentiation in a floodplain, Poyang Lake, China

“…In the middle and low elevation areas, the growth of Carex spp. was largely in response to lake water level (Feng et al, 2020; Li, Qian, et al, 2019; Li, Yu, et al, 2019). As the water level decreased, areas at high elevations were firstly exposed; this could provide a moderately environment for the growth of Carex spp.…”

Land use legacy footprint in Mediterranean forest soils: An infrared spectroscopy approach

“…• Linear mixed effect models Based on previous studies with similar sampling design (Santonja et al, 2018;Feng et al, 2019), the statistical analyses of the data were realized using linear mixed-effect models (LME) with significance levels indicated as * for P < 0.05, ** for P < 0.01 and *** for P < 0.001, followed by Tukey HSD tests for post hoc comparisons (P < 0.05). Linear mixed effect models allow the analysis of complex datasets with hierarchical structures, avoiding the shortcomings of ANOVAs and multiple regression.…”