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提高粮食产量一直是农业的根本任务.那么怎样才能有效提高粮食产量呢?其中一个答案是施肥.第一位提出科学肥料学说的是德国化学家李比希(1803—1873).李比希通过分析农作物及其果实的成分得出结论:农作物生长需要碳、氢、氧、氮、磷、钾、钙、镁等元素.碳、氢、氧可由植物的光合作用获得,光合作用将水(H_2O)和二氧化碳(CO_2)合成糖类(葡萄糖、果糖、淀粉、纤维素等).钙、镁在农作物中属于微量元素,土壤可以供给.氮、磷、钾是农作物的三大营养元素,只有供应充足才能提高产量,但土壤中这三种元素的含量很少.在氮、磷、钾三种元素中,粮食对氮的需求量最大,氮对粮食产量的提高也最为关键.在氮、磷、钾三种元素中,钾肥比较容易解决,草木灰中就含有较多的钾离子.自然界中的磷元素也比较多,最重要的矿石是磷灰石,其主要成分是磷酸钙[Ca_3(PO_4)_2].但磷酸钙难以溶解,所以很难被植物直接
One of the answers is fertilization. The first scientist to put forward the theory of scientific fertilizers is the German chemist Li Bixi (1803-1873). Li Bixi through the analysis of crops and their The composition of the fruit concludes that crop growth requires elements such as carbon, hydrogen, oxygen, nitrogen, phosphorus, potassium, calcium, magnesium, etc. Carbon, hydrogen and oxygen are obtained from the photosynthesis of plants and photosynthesis combines water (H 2 O) and carbon dioxide (Glucose, fructose, starch, cellulose, etc.) Calcium and magnesium are trace elements in crops and can be supplied by the soil Nitrogen, phosphorus and potassium are the three major nutrients of crops and can only be increased if the supply is sufficient , But the content of these three elements in the soil is very little.Nitrogen, phosphorus and potassium in three elements, the demand for grain nitrogen the most, nitrogen is also the key to improving food production.In nitrogen, phosphorus and potassium Among the elements, potassium fertilizer is easier to solve, and ash contains more potassium ions.Phosphorus is also abundant in nature, and the most important ore is apatite, whose main component is calcium phosphate [Ca_3 (PO_4) _2]. Calcium phosphate is difficult to dissolve, it is difficult to directly plant