Aquatic Macrophytes in Morphological and Physiological Responses to the Nanobubble Technology Application for Water Restoration

Abstract

Nanobubble technology, as an emerging and sustainable approach, has been used for remediation of eutrophication. However, the influence of nanobubbles on the restoration of aquatic vegetation and the mechanisms are unclear. In this study, the effect of nanobubbles at different concentrations on the growth of Iris pseudacorus (Iris) and Echinodorus amazonicus (Echinodorus) was investigated. The results demonstrated that nanobubbles can enhance the delivery of oxygen to plants, while appropriate nanobubble levels will promote plant growth, excess nanobubbles could inhibit plant growth and photosynthesis. The nanobubble concentration thresholds for this switch from growth promotion to growth inhibition were 3.45×10 7 and 1.23×10 7 particles/mL for Iris and Echinodorus, respectively. Below the threshold, an increase in nanobubble concentration enhanced plant aerobic respiration and ROS generations in plants, resulting in superior plant growth. However, above the threshold, high nanobubble concentrations induced hyperoxia stress, particularly in submergent plants, which result in collapse of the antioxidant system and the inhibition of plant physiological activity. The 2 expression of genes involved in modulating redox potential and the oxidative stress response, as well as the generation of relevant hormones, were also altered. Overall, this study provides an evidence-based strategy to guide the future application of nanobubble technology for sustainable management of natural waters.

Effects of nanobubble in subsurface drip irrigation on the yield, quality, irrigation water use efficiency and nitrogen partial productivity of watermelon and muskmelon

“…NBW may serve to enhance photosynthesis, stimulate GA hormone secretion, as well as affecting the distribution of microbial communities by increasing soil oxygen content which effectively promotes the absorption and transformation of nutrients by crops. (Wang et al, 2020;Zhou et al, 2020;Motoka et al, 2013;Wu et al, 2019). All of these factors further promoted yield increases.…”

Nanobubble Watering Affects Nutrient Release and Soil Characteristics

“…However, O 2 NBs could improve the organic fertilizer utilization by soil microbes that could indirectly support the plant growth by increasing the plant-available N and P . Moreover, O 2 NBs could enhance O 2 delivery to soil and promote the aerobic respiration of plants and the ROS generations, which could activate plant proliferative pathways . N 2 NBs seem to increase the soil nitrogen, which is the most limiting factor in the production of crop .…”

Oxygen Nanobubbles for Lake Restoration—Where Are We at? A Review of a New-Generation Approach to Managing Lake Eutrophication

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