| Short cycle facilities, agricultural cultivation, planting single structure, cropping index is high, and the pursuit of high yield and high efficiency in the production process often excessive nitrogen fertilizer. Plants absorb a lot of fertilizer not only will cause soil salinization affecting production but also cause eutrophication of rivers, lakes and other water bodies, resulting in serious environmental problems. Wetland is a new sewage treatment technology, compared with conventional sewage treatment technology has an economic, easy to operate, efficient, stable, low energy consumption, without the advantages of chemical reagents, has broad application prospects. Current research on wetland wetlands focused on multi-bed matrix mix aspects of plant selection, plant decontamination effects, and wetland plants adapt to physiological metabolism wetland environment to study the molecular mechanisms less. Previous studies indicate that wetland plants play an important role in the purification process of the sewage, but the contribution of the matrix and the role of microorganisms and reports are not many wetland plants absorb the molecular mechanisms of metabolic waste farmland has not been reported. The research farm waste vegetable growing area around Yuxi Qilu produce processing Canna, dry umbrella bamboo, water hyacinth and Tamba big black beans, through the analysis of wastewater treatment Canna farmland, drought umbrella bamboo, water hyacinth and Tamba four large black bean plants purification of wastewater composition and metabolic intermediate screening dominant plants, and analog operation mode wetlands under laboratory conditions and changes in the ability of plant physiological and biochemical characteristics in comparison wetland plants, agricultural waste matrix and microbial purification and analysis of nitrate uptake and metabolism-related enzyme activities and regulatory mechanisms study the physiological basis of wetland plants purify wastewater and molecular mechanisms of farmland, Made the following key findings:1, Using the national standard method (GB3838,2002) analysis of the main components of farmland contaminated wastewater, wastewater pH results indicate that farmland is7.3, NO3-concentration of4.79mg/L, PO43-concentration of0.879mg/L, respectively, the state standard24and44times. The farmland with wastewater treatment Canna, dry umbrella bamboo, water hyacinth and Tamba big black beans, analyze the effect of different plants absorb nitrogen, phosphorus, fresh weight change and pollution on farmland in wastewater before and after treatment of metabolic components. The results show that with the treatment time increases, canna, water hyacinth beans and Tamba large farm wastewater treatment significantly reduced the concentration of NO3-, drought umbrella bamboo wastewater treatment NO3-concentration decreased but did not reach a significant level; Canna, dry umbrella bamboo and water hyacinth wastewater treatment farmland PO43-concentration decreased by a big margin and Tamba big black bean processing wastewater PO43-concentration decreased only slightly. After processing canna, water hyacinth and large black beans, fresh dry fresh weight increase, but a small amount of heavy bamboo umbrella has appeared reduced. These results indicate that the four plants Canna farmland and water hyacinth wastewater purification effect is good, dry beans and a large umbrella bamboo farm wastewater purification capacity is relatively weak. Under the same treatment conditions, analyze changes in various organs of four plants NO3and PO4"levels. The results showed that canna, water hyacinth and Tamba big black bean roots, stems, leaves three organs of NO3water treatment levels are higher than the control group, the dry umbrella Zhugen elevated NO3-content in the stems and leaves, but NO3-decreased content. The content of each organ PO43-Canna and water hyacinth has increased, the content of each organ PO43-dry Tamba large umbrella bamboo and black beans decreased. NMR analysis showed that canna leaf through farmland wastewater generated in large amounts of nitrogen transport amino acids and soluble carbohydrates, and dry umbrella bamboo and water hyacinth leaves but no such changes. Description Canna wastewater pollution of farmland conversion component ability, the ability to adapt to a strong agricultural waste generated, and several other plant transformation capacity contaminated ingredient is weak, the strong agricultural wastewater generated when subjected to stress. Therefore, in-depth study for subsequent experiments select Canna.2, Canna as experimental material to simulate in a greenhouse constructed wetland works to establish an experimental model to study the matrix filler farmland wastewater nitrogen and phosphorus removal components, and through stomatal conductance and transpiration rate, malondialdehyde (MDA) and antioxidant enzyme system impact study of farmland water canna physiological characteristics. Experimental results show that the matrix selected three kinds of filler (crushed stone, ceramic, zeolite) on farmland in wastewater purification NO3-no it will cause water samples NO3concentration, for the purification of PO43-have some effect, but the effect is less than plants. Three separate measurement matrix further purification effect found that the molecular sieve adsorption of NO3strong ceramic farmland gravel and waste water NO3-adsorption of small, still contains some of its own NO3-. Three matrix component of farmland has purify wastewater PO43-role capability to purify its large order of small ceramic, zeolite and gravel. In the fields of wastewater treatment environments, canna leaf stomatal conductance and transpiration rate of the processing time increases with decreased MDA content increased, indicating a certain extent of oxidative stress when grown in farm wastewater Canna environment; treatment in an environment containing matrix MDA content is lower than when the matrix-free treatment, indicating that the adsorption of matrix components make Canna pollution oxidative stress suffered by a certain degree of ease. Different organs of SOD, POD, CAT activity increased, which helps reduce oxidative stress injury, this may be a mechanism to adapt to agricultural wastewater Canna environment. Through the matrix of different components of wetland microbial isolation and expansion of training a certain amount of re-inoculation into wetland model, examine the role of microbial removal of farmland wastewater nitrogen and phosphorus growth after a period of time. The results show that in a laboratory environment, microbial nitrogen in waste water on farmland, little phosphorus removal, purification plants and lower than the matrix. 3, Under the conditions of agricultural wastewater treatment, analysis canna roots, stems, leaves and nitrogen absorption associated with the plasma membrane H+-ATPase and H+-pump activity changes. The results show that the processing time increases with the plasma membrane H+-ATPase and H+-pump activity increased, indicating agricultural wastewater treatment can improve and plasma membrane H+-ATPase and H+-pump activity. Magnesium ions through the promotion of14-3-3proteins and plasma membrane H+-ATPase binding increases the plasma membrane H+-ATPase activity; VA plasma membrane H+-ATPase is a specific inhibitor. Magnesium chloride and were treated by VA canna change the plasma membrane H+-ATPase activity, and verify the relationship between agricultural wastewater treatment Canna in the activity of plasma membrane H+-ATPase and agricultural waste water NO3-absorption. The results showed that:150mM chloride pretreatment8h can significantly increase Canna absorption of agricultural waste water NO3-, and plasma membrane H+-ATPase and H+-pump activity also significantly increased; while adding100mM VA pretreatment8h significantly reduce Canna farmland wastewater NO3-absorption, plasma membrane H+-ATPase and H+-pump activity was also significantly reduced; immunoprecipitation analysis showed that farmland makes14-3-3protein and wastewater treatment significantly increased plasma membrane H+-ATPase protein, magnesium chloride pretreatment enhanced Canna roots14-3-3protein binding and phosphorylation of the plasma membrane H+-ATPase, indicating that by enhancing the canna roots14-3-3proteins with the plasma membrane H+-ATPase expression and interaction can increase the plasma membrane H+-ATPase and H+-pump activity, and thus enhance the absorption efficiency of farmland Canna wastewater NO3-in. Under the conditions of agricultural wastewater treatment, analysis canna roots, stems, NR NR and changes in leaf nitrogen metabolism associated with glutamine synthetase GS activity. The results show that with the increase in processing time canna roots and stems NR activity is rising, leaves NR activity first increased and then decreased; GS activity among the three organs showed an increasing trend, indicating increased agricultural wastewater treatment Canna various organs NO3-reduction and assimilation ability, but the exact molecular mechanisms require further study. |
PDF Full Text Request