Effects Of Chloric Snow Thaw Agents On Sewage Outlet Water Quality Of The City And Crop Seed Germination

Objective:Chloric snow thaw agents as a source of widespread, cheap, good snow effects of deicing chemical are widely used in many countries. The use of deicing salt bringing a series of economic losses and environmental problems have attracted people,s attention. In this study we monitored the quality of the water from the sewage outfall of the city to monitor water quality in spring and autumn, and the effects of chloric snow thaw agents on seed germination and germination process material content and the activities of antioxidant enzyme were studied for the correct evaluation of the chloric snow thaw agents melting agent Problems and provide a scientific basis for rational use.Method:1. The changes of water quality in City sewage outlet in spring and autumn.Selected the main municipal sewer outfall in Changchun City, the sewage outlet is located in south of Changchun Bridge, the West Bank Yitong about 500m, the water flow year round there, which dynamic monitoring. Sampling water a month in each season of spring and autumn, Collected once every ten days, collected five water samples every time. Collected water samples for total hardness, ammonia nitrogen, COD, Na+, Ca2+, Mg2+, K+, Cl-, SO42-content of Determination.2. The effects of crop seed germinationSelect the five commonly grown crops in northern seed, that is, corn, soybean, rice, cabbage, cucumber seeds as experimental material, deicing salt chlorine concentration gradient with distilled water for the preparation of 0,4.9 g/L,7.1 g/L, 10.1 g/L,14.4g/L,20.6g/L,29.4g/L,42.0 g/L,60.0 g/L in deicing salt solution. Selected the seeds which uniform size, the appearance of smooth with no damage full by germination method on paper bed,25℃dark culture medium was changed daily to half the length of shoot to seed germination as the standard, and record the number of seeds per day. remove the seeds after 7 days, measuring shoot length, shoot fresh weight, root length, root fresh weight, and calculate the LC50 which chloric snow thaw agents of various crop seeds.Based on the above, the preparations of the five crops were 1/8LC50, 1/4LC50, 1/2LC50 of deicing salt solution. Distilled water control group, using the culture method and conditions, when the germination rate of control group reached 90%, the seeds were determined according to various indicators of pre-treatment methods were carried out. Determination of seed protein content, proline content, total amino acid content, MDA content and SOD, CAT, POD activity and other indicators.Results:1. Municipal sewage outlet water quality:The water of sewage outlet, total hardness, chemical oxygen demand, ammonia, Ca2+,Mg2+,K+,Na+,Cl-, etc. in the spring with the weather warm decreased, while the fall of the indicators to monitor the value of all Within an order of magnitude in volatility. The water SO42- in spring and autumn showed no significant change.2. Chloric snow thaw agents on seed germination of crops:Chloric snow thaw agents on the inhibition of seed germination of various crops in varying degrees, corn, cucumber, rice, cabbage, soybeans, LC50, respectively: 24.71g/L,20.22g/L,16.25g/L,11.99g/L,10.64g/L. With the increase of deicing salt concentration in the roots of the crop seeds and bud length gradually shortened (P<0.0056), the weight of shoots decreased significantly (P<0.0056), showed a dose-response Relationship. Seeds of various crops also decreased, showed a significant negative correlation (P<0.05).3. Chloric snow thaw agents on germination of crop seeds in the content of the course material:Cabbage and cucumber seeds of species of proline content increased with the concentration of deicing a downward trend (P<0.05), soybean, rice high dose group was significantly higher than Control group (P<0.05).the soluble protein content of cucumber Seed decreased (P<0.05), cabbage, soybeans, rice, corn seed proteins content and high concentration groups were significantly higher than Control group (P<0.05). Free amino acid content in seeds increased with the concentration of deicing salt, cabbage, rice showed decreased and then increased trend is manifested in cucumber and soybean gradually decreased (P<0.05).4. Deicing salt on germination of crop seeds in the enzyme content of the course:With the increase in chloric snow thaw agents concentration, the MDA content in all kinds of plant seeds showed a downward trend, high-dose group was significantly lower than the control group (P<0.05.) SOD activity in Cabbage and soybean showed that increased at first and then decreased (P<0.05), cucumber, rice will be gradually increased (P<0.05), corn decreased gradually (P<0.05). CAT activity in Cabbage, soybean, rice and corn decreased gradually (P<0.05), cucumber increased at first and then decreased (P<0.05). POD activity of both showed a downward trend (P<0.05).Conclusion:1.The ion content in the water quality of Changchun City sewage outlet when using Chloride deicing salts is high, especially Cl", Na+ is more evident.2. Chloric snow thaw agents for various crops were LC50:corn, cucumber, rice, cabbage, soybeans, LC50, respectively:24.71g/L,20.22g/L,16.25g/L, 11.99g/L,10.64g/L. To all sorts of crop seed germination represent high concentrations of apparent inhibition. Crop seed germination process of the protein, amino acid, proline content and antioxidant enzyme activity of interference.