Interactive effects of waterlogging and atmospheric CO₂ concentration on gas exchange, growth and functional traits of Australian riparian tree seedlings

Abstract

The ability to survive and thrive in repeatedly waterlogged soils is characteristic of plants adapted to riparian habitats. Rising atmospheric CO2 has the potential to fundamentally alter plant responses to waterlogging by altering gas exchange rates and stoichiometry, modifying growth, and shifting resource‐economic trade‐offs to favor different ecological strategies. While plant responses to waterlogging and elevated CO2 individually are relatively well characterized, few studies have asked how the effects of waterlogging might be mediated by atmospheric CO2 concentration. We investigated interactive effects of elevated (550 ppm) atmospheric CO2 and waterlogging on gas exchange, biomass accumulation and allocation, and functional traits for juveniles of three woody riparian tree species. In particular, we were interested in whether elevated CO2 mitigated growth reduction under waterlogging, and whether this response was sustained following a refractory “recovery” period during which soils were re‐aerated. We found species‐specific effects of atmospheric CO2 concentration and waterlogging status on growth, gas exchange, and functional traits between species, and no evidence for a general effect of elevated CO2 in mediating plant responses to flooding. For one specie, Casuarina cunninghamiana, elevated CO2 substantially increased growth, but this effect was entirely removed by waterlogging, and there was no recovery following a refractory period. Differential responses to combined waterlogging and elevated CO2 among species may result in compositional changes to riparian plant communities and associated changes in ecosystem functioning.

Are commercial sweet cherry rootstocks adapted to climate change? Short‐term waterlogging and CO2 effects on sweet cherry cv. ‘Burlat’

“…Another response common to the aforementioned stresses was detected in these previous reports: amelioration of the drop in the photosynthesis rate by an increment in the a[CO 2 ]. This effect was detected in the current experiment and was also found by Arenque et al () in Senna reticulata and Lawson et al () in Casuarina cunninghamiana and Eucalyptus camaldulensis , the only two reports in which the effects of e[CO 2 ] on photosynthesis under flooding have been studied.…”

“…In fact, this phenomenon is reported in many papers. However, little has been written about the effect of CO 2 on the contrary situation, waterlogging ( W ) (Ershova et al ; Shimono et al ; Arenque et al ; Lawson et al ). This is an important gap in the literature, because W is an important element in climate change.…”

Preserving the nutritional quality of crop plants under a changing climate: importance and strategies

“…Nevertheless, increasing CO 2 concentration not only mitigated all these effects but also induced the production of soluble sugars and starch in the leaf (Pérez-Jiménez et al 2017b). In woody plants, Lawson et al (2017) found species-specific effects of CO 2 concentration and waterlogging on plant growth, gas exchange, and functional traits, and no evidence for an overall effect of eCO 2 in mediating plant responses to flooding. In pea and soybean, an association among tolerance to hypoxia (induced by flooding), the rate of reactive oxygen species production, and antioxidant enzyme activities was recognized.…”

Two minuses can make a plus: waterlogging and elevated CO2 interactions in sweet cherry (Prunus avium) cultivars

“…Therefore, if we wish to predict the future response of plants to climate change, the study of both phenomena (W and elevated CO 2 ; eCO 2 ) separately would be controversial because these two environmental negatives could make a ‘plus’. Although eCO 2 and other abiotic stressors have been widely studied (Taub et al , Wall et al , Hamilton et al , Geissler et al , Vu and Allen , Piñero et al , , Yua et al ), the combined effect of W and e[CO 2 ] has been scarcely studied (Ershova et al , Shimono et al , Arenque et al , Lawson et al , Pérez‐Jiménez et al ) and, it has recently been studied in fruit trees for the first time (Pérez‐Jiménez et al ) but never on the cultivar response.…”