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土壤的酸碱性是影响土壤肥力的一个重要因素,而且会直接影响到作物的生长。不同的作物耐酸、碱不同,通过测定可合理施肥改良土壤;选择适宜的作物,以取得丰收。而土壤中速效氮、磷、钾的含量的测定,则可识别土壤的肥力如何。制订出合理的措施,进行施肥,以最少的成本获最好的收成。本调查采用非石灰性土壤的测定方法,对学校周围大田进行调查,既增加学生知识,培养学生能力,也为社会提供一定有用的材料。 1.原理: 土壤的酸、碱性是用pH试纸对不同酸碱、度显出不同颜色而确定的,如用pH=5.5—.09的精密pH试纸即可。土壤速效氮肥是硝态氮
The acidity and alkalinity of the soil is an important factor affecting the soil fertility, and it will directly affect the growth of the crop. Different crops are resistant to acids and alkalis, and the soil can be properly fertilized to improve soils by selecting the suitable crops. The determination of available N, P, and K in soil can identify the fertility of the soil. Develop reasonable measures for fertilization and get the best harvest at the least cost. This survey uses non-calcareous soil measurement methods to investigate the fields around the school. This will not only increase students’ knowledge, develop students’ abilities, but also provide the society with certain useful materials. 1. Principles: The acidity and alkalinity of the soil are determined by pH test papers for different acids, alkalis and degrees. For example, a pH test paper with a pH of 5.5-.09 can be used. Soil available nitrogen fertilizer is nitrate nitrogen