The Migration Of Cl~- In The Soil And Its Effects On The Physical And Chemical Properties Of The Soil After The Long-term Use Of Chloride-containing Fertilizers

This study is based on brown soil chlorine-containing fertilizer long-term test base in Shenyang Agricultural University, measuring chlorine ion content of each growth stages in 2014 and soil ammonium nitrogen and nitrate nitrogen content, soil alkaline hydrolysis nitrogen, available phosphorus and available potassium content, soil exchangeable calcium and magnesium content, soil exchangeable hydrogen, aluminum, acid content, soil pH, aggregate stability, content of organic matter and total nitrogen in aggregate, soil moisture content, bulk density, capillary porosity and field capacity indices including of the harvest. Analyzing the relations among the various indicators, studying the effects on the physical and chemical properties of the soil after the long-term use of chloride-containing fertilizers.To provide a scientific basis for applying chlorine-containing fertilizer and compound fertilizer. The main results of research are followed:(1) The accumulation amount of chloride ions in the soil is only a small,after the long-term use of chloride-containing fertilizers. And the accumulation content of chlorine in the soil is much lower than the chlorine concentration in the soil that the plant can resist,after 31 years continuous long-term application, whether high chlorine treatment or low chlorine treatment. So it will not affect the growth and development of the maize, and will not have poison on the maize to apply chloride-containing fertilizers for long term. The survey results about the biological traits of maize of each growth stages in 2014 also shows that the maize grow well after long-term use of chlorine-containing fertilizers.(2) It has no significant effect on the content of soil available nutrient, but has certain influence on the content of exchangeable calcium and magnesium to apply chlorine-containing fertilizer for long term. Especially high chlorine treatment, which leads the content of exchangeable calcium and magnesium in the soil to decrease significantly. Due to the chlorine’s strong mobility, it is easy that chloride ion will move down into the soil with the water, and calcium and magnesium ions will also run off with the loss of chlorine as accompanied ions, leading to a lower content of calcium and magnesium. Exchangeable calcium and magnesium in the soil and aggregate stability are significantly related, the high chlorine treatment reducing the stability of soil aggregate by lowering the content of exchangeable calcium.(3) The content of exchangeable hydrogen and aluminum, exchangeable acidity in the soil increases, because of the long-term use of chlorine-containing fertilizers, especially high chlorine treatment, causing the content of exchangeable acidity and aluminum getting significantly higher than other treatments, soil pH is also significantly lower than other treatment, however the content of exchangeable hydrogen has a smaller contribution to reducing the soil pH. Applying chlorine fertilizer into the soil, a large number of hydrogen ions will be swapped out by the cationic of fertilizer, reducing the soil pH.(4) Long-term using chlorine-containing fertilizers, high chlorine treatment has a significant effect on soil physical properties, the influence of low chlorine treatment was not significant. Through long-term continuous using chlorine-containing fertilizer, the soil bulk density of high chlorine treatment increase, capillary porosity decreases, field capacity decreases, soil moisture content reduces.(5) Effect on maize biological traits, agronomic traits and plot yield is not significant after long-term use chlorine-containing fertilizers. In the case of three kinds of NPK nutrients being plenty, the production of maize can arrive normal.