Work

Comparative flooding tolerance of Typha latifolia and Phalaris arundinacea in wetland restoration: Insights from photosynthetic CO2 response curves, photobiology and biomass allocation

Year: 2023

Type: article

Abstract: Tall helophytes such as Typha latifolia and Phalaris arundinacea often rapidly colonise after rewetting of former agricultural soil and are therefore often the first plants to contribute to the soil carbon pool. In this study we carried out a mesocosm experiment where these two species grew at three different water levels relative to the soil surface (-15 cm, 0 cm, +15 cm). After eight weeks’ growth, measurements of photosynthetic CO2-response curves, stomatal conductance and chlorophyll fluorescence of photosystem II were carried out to detect flooding stress. After 10 weeks’ growth, the plants were harvested and biomass production, biomass allocation and specific leaf area were determined. T. latifolia had a stable photosynthetic performance across all water level treatments, which resulted in an overall higher aboveground and belowground production than P. arundinacea. In contrast, P. arundinacea showed a decrease in photosynthesis rates and signs of flooding stress as impairment of the photosynthetic apparatus with increasing water level. Moreover, increasing water level resulted in maintenance of aboveground organs for P. arundinacea but a decrease in allocation to belowground organs. Moreover, P. arundinacea did not invest in a higher specific leaf area to counter the decreased photosynthesis under flooding. From -15 cm to 0 cm water levels, P. arundinacea showed a 68% reduction in belowground biomass, which has negative implication for carbon retention immediately after rewetting. In contrast, recolonization of T. latifolia is likely to be a suitable contributor to the soil carbon pool due to its stable physiology and high above- and belowground biomass production at all water depths, and also likely under natural water level fluctuations. We showed that even though both species are generally considered wetland plants, they are likely to support considerably different photosynthetic carbon assimilation and soil carbon sequestration rates.

Source: Heliyon

DOI: 10.1016/j.heliyon.2023.e23657

Authors: Asger Buur Jensen, Franziska Eller, Brian K. Sorrell

Institution: Aarhus University

Language: English

Topic: Plant responses to water stress

Subfield: Plant Science

Field: Agricultural and Biological Sciences

Domain: Life Sciences

SDGs: Life on land, Climate action

Open Access status: gold

Estimated APC paid: $2,100