Effect of Nano-Titanium Dioxide on Reed Biomass (Phragmites australis)

Nano titanium dioxide is widely used in chemical, pharmaceutical food, clothing and water treatment industries. In the aspect of nano biological effects on plants, some scholars have studied the biological toxicity test of nano titanium dioxide and its effects on seed germination and seedling growth of plants. Currently, data of nano biological effects on plants are mostly based on the laboratory design research. Moreover, the experimental data can only provide rules of plant growth at a certain stage. Complete testing data of plants which grow naturally in the outdoor are not enough. The biological effects of nano titanium dioxide on a complete growth cycle and biomass of plants have not been reported yet. In this experiment, the biological effects of nano titanium dioxide on the whole growth cycle of reed under natural growth conditions have been recorded and studied. Reed is a kind of aquatic and wetland plant which is widely distributed in the worldwide, and plays an important role in the removal of pollutants in water, water purification and ecological restoration of the water system. The results show that the positive biological effect of nano titanium dioxide on reed is extremely significant. The biomass of reed of experimental group treated with nano titanium dioxide is 97.5% higher than that of the control group, plant size increases 47.7%, the plant height increases 23.3%, and the photosynthetic increases by 88.3% in sunny day and 72.5% in cloudy day. At the same time, nano titanium dioxide can significantly reduce the weed coverage rate of the test area. The weed coverage rate of the experimental group is only 6%, and that of the control group is 57%. This study, by using the positive biological effect of nano titanium dioxide on reed, increases the biomass of reed, lifts reed’s periodic yield, achieves efficient removal of pollutants in water and could provide a safe, efficient and simple new way of water purification and protection of artificial wetlands and lakes, reservoirs and other water sources.