| In order to explore the ecological effects of nanomaterials in the soil environment, three exogenous nanomaterials (nSiO2, nTiO2 and nZnO) were added to the paddy soil of potted rice seedlings respectively, and the effects of three kinds of nanomaterials with different concentrations on the growth and rhizospheric soil fertility of rice seedling were analyzed. The results showed that the fresh weight, dry weight and plant height of rice seedlings treated with 0.5 mg/g nZnO increased, but 1, 2 mg/g nZnO treatment was just the opposite. The dry weight and plant height of rice seedlings treated with 2 mg/g nSiO2 decreased significantly. The nitrogen content of rice seedlings treated with 0.5 and 2 mg/g nSiO2 was significantly decreased. P content in rice seedlings treated with three concentrations of nZnO increased and K content decreased significantly. The effects of 1, 2 mg/g nTiO2 treatment on plant growth, main nutrient (N, P, K) content and soil available nitrogen, available phosphorus, available potassium were not significant. Soil pH and organic matter contents decreased after treated with nSiO2 and nTiO2 at three concentrations, soil available nitrogen and available phosphorus contents increased significantly after treat with 1and 2 mg/g nSiO2, and soil available phosphorus and available potassium contents decreased after treated with nZnO at three concentrations. The activity of soil acid phosphatase was significantly inhibited and that of catalase was significantly promoted after treated with all three kinds of nanomaterials, and the activities of soil invertase and urease were significantly inhibited under three different concentrations of nZnO. All in all, among three nanomaterials mentioned above, nZnO treatment has the strongest influence on growth, nutrient uptake and rhizospheric soil enzyme activity of rice seedings. |
