Tundra is one of the most sensitive biomes to climate warming. Understanding plant eco-physiological responses to warming is critical because these traits can give feedback on the effects of climate-warming on tundra ecosystem. We used open-top chambers following the criteria of the International Tundra Experiment to passively warm air and soil temperatures year round in alpine tundra. Leaf size, photosynthesis and anatomy of three dominant species were investigated during the growing seasons after 7 years of continuous warming. Warming increased the maximal light-saturated photosynthetic rate (Pmax) by 43.6% for Dryas. octopetala var. asiatica and by 26.7% for Rhododendron confertissimum across the whole growing season, while warming did not significantly affect the Pmax of V. uliginosum. The leaf size of Dr. octopetala var. asiatica and Rh. confertissimum was increased by warming. No marked effects of warming on anatomical traits of Dr. octopetala var. asiatica were observed. Warming decreased the leaf thickness of Rh. confertissimum and Vaccinium uliginosum. This study highlights the species-specific responses to climate warming. Our results imply that Dr. octopetala var. asiatica could be more dominant because it, mainly in terms of leaf photosynthetic capacity and size, seems to have advantages over the other two species in a warming world.

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A major concern with container seedlings is root circling and deformation that will affect post-planting performance and stability. To improve root quality, 3-year-old Begonia ( Malus ×  micromalus) plants were grown in the containers treated on interior surfaces with different concentrations of copper hydroxide (Cu(OH)2) (0, 40, 80, 120, 160, and 200 g L−1) for 1 year. Compared with the standard container control (SC) and carrier asphalt container control (AC), the number of terminal lateral roots and lateral root volume were increased by 21% and 13% at 80 and 120 g L−1 Cu(OH)2 but decreased by 8% and 10% at 200 g L−1 Cu(OH)2. Only 80 g L−1 Cu(OH)2 increased the plant height and root weight, while other concentrations of Cu(OH)2 resulted in the declines. Phosphorus and potassium were improved with lower concentrations of Cu(OH)2 but decreased with 160 and 200 g L−1 Cu(OH)2. No significant difference in the concentrations of soluble protein and sugars in leaves was observed between Cu(OH)2 treatments and the controls. AC decreased nitrogen concentration in leaves by 12% over the SC across the whole growing season and increased taproot diameter by 17%. Our results indicate that 80 g L−1 Cu(OH)2 was the optimum concentration for root pruning and the maintenance of physiological function. Disadvantages in growth and physiology gradually showed up with increased concentrations.

A nonlinear dynamical model for the plankton population in a fixed sea area under the influence of asymmetric multiple factors, including atmospheric CO2 concentration, atmospheric temperature, nutrient concentration, seawater temperature, light intensity, and predator density is proposed to address the survival of the plankton population due to global warming. The model’s accuracy is confirmed by comparison with actual data, and numerical simulations are carried out to justify the relevant findings. The results suggest that increasing plankton’s ability to absorb atmospheric CO2 or regulate atmospheric temperature can help to mitigate global warming. Furthermore, if the population density of fish, the primary predator of plankton, falls within a certain range, the increase in atmospheric temperature will be mitigated. Additionally, the stability conditions for the suggested model are obtained, along with the equilibrium point of the system. Overall, this paper considers the effects of asymmetric multifactor interaction on plankton population density and establishes a mathematical connection between environmental ecosystems and plankton that might aid in addressing the challenges posed by global warming and preserving the plankton population.

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