Effects Of Maize Straw Incorporation For Successive Years On Soil Physical-chemical Properties And Crop Growth

This paper is studied by the methods of field experiment and investigation. Tests of different maize straw returning to the field were conducted on tideland of semi-arid area of Quzhou, Hebei Province. Soil was sampled from different treatments in order to measure soil water content, nitrate nitrogen, ammonium nitrogen, soil enzyme, soil organic matter, and soil bulk density, in addition to analysis of other soil physical and chemical properties. The results showed that:Tests of no-crushed and crushed straw returning to the field for six continuous years showed that, the soil organic matter in 0~15 centimeter of the no-crushed and the crushed increased by 22.12% and 14.91%, in the same case, they increased by 10.09% and 10.00% in 15~30 centimeter respectively, while the check decreased by 7.76% and 5.56%, the difference is remarkable. Maize straw returning to the field also decreased soil bulk density.Maize straw returning to the field can increase the soil total nitrogen and inorganic nitrogen content. Total and available phosphorus content decreased. It can also increase soil available potassium. The carbon-nitrogen ratio in soil stays between 5.89 to 9.33:1, each treatment is near, as the time went on, the carbon-nitrogen ratio in soil becomes lower and lower, and is less than 15:1.For the yields of six-year straw returning to the field, treatments of the no-crushed and the crushed are more than that of the check by 6.43% to 31.69% and 8.12% to 22.52% respectively. Cost of treatment of the no-crushed descended by 40.32%, and its benefit ascended by 22.48% compared with the check test, it had notable effect on decreasing cost and increasing benefit.This experiment also added two treatments of upstanding straw and crushed straw returning to the field with no-tillage, the effects of straw returning to the field with no-tillage on crop growth and yield were explored, treatment of upstanding straw returning to the field with no-tillage was proved feasible and further study was necessary.In a short word, compared with other styles of straw returning to the field, treatment of no-crushed straw returning to the field had notable effects on building up soil physical and chemical properties, adding soil nutrient, increasing crop production and net income, in addition, it also had merits of saving time, labor and money, which could be accepted by most peasants for its convenience and feasibility. It's a perfect straw-amendment style and should make popular in china northern dry farming district.