Non-pollution vegetable rational fertilization

1. Select fertilizer types that have no or little effect on the quality of vegetables after application. If potassium fertilizer is to be applied with potassium sulfate fertilizer, no potassium chloride fertilizer can be applied; in the application of nitrogen fertilizer, ammonium nitrogen or ammonium hydroxide fertilizer should be used, and nitrate nitrogen fertilizer should be used less or not. This can not only obtain high yield, but also reduce the content of nitrate and nitrite in vegetable products, improve the quality of vegetables, and at the same time reduce the pollution of nitrate by soil.

2. Use lime nitrogen, carbon disulfide, etc., which have nitrogen-suppressing properties, to reduce the nitrate and nitrite content in vegetables to reduce and control the effect of excess nitrates on soil and vegetables.

3, using a reasonable method of fertilization. For the base fertilizer, a combination of deep application and shallow application should be adopted to meet the fertilizer needs of different growth stages of vegetables. The combination of Puxi and concentrated application was adopted to meet the fertilizer requirement and improve the utilization rate at the seedling stage. It is best to apply furrows and acupoints to topdressing, and alternate methods of chemical fertilizers and human waste should be applied after the application of watering methods to increase the utilization of fertilizers and reduce the accumulation of nitrates and nitrites in the soil. For solar greenhouse vegetables, which can not be diverted or applied by dark irrigation under the membrane in winter, the fertilizer can be dissolved in a container first, and then a thin tube is used to dilute into the water to make the fertilizer evenly applied to the people.

Catalyst refers to a substance which can change the reaction speed in a chemical reaction and whose composition and mass remain unchanged after the reaction. The catalysts that speed up the reaction are called Positive Cata-lyst and the slower ones are called Negative Cata LYST or moderators. Generally speaking, the catalyst is to correct the catalyst. These catalysts are widely used in industry, especially in organic chemical industry. They are of great significance, for example, catalysts are needed for the preparation of sulfuric acid by contact method, the hydrolysis of synthetic ammonia, esters and polysaccharides, and the hydrogenation of oils and fats. Commonly used catalysts are metals, metal oxides and inorganic acids. If the catalyst is a solid, the reactant is a gas, forming a heterogeneous catalytic reaction, this catalyst, sometimes called a catalyst or contact agent.