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一、绿肥在农业生态系统中的基本功能 通过种植利用绿肥作物,来恢复提高土壤肥力,是我国古代劳动人民在农业生产上的一项重大创造。 在人工合成氮肥工业发明之前的漫长岁月中,农业生产的氮素来源绝大部分来自生物固氮。即使在氮肥工业高度发达的今天,全世界每年生物固氮的总量估计有17,500万吨,相当于工业固氮的4倍。从整个农业发展的历史来看,即使说“没有生物固氮,便没有农业生产,”也并不过分。如从保持生态平衡,维持土壤肥力,防止环境污染,节约能源成本等要求看,单纯地走“无机农业”或“石油农业”的道路显然是不可取的,生物固氮将来仍应是农业生产的主要氮源。
First, the basic functions of green manure in agricultural ecosystem Through the cultivation and utilization of green manure crops to restore and improve soil fertility, it is a major creation of the ancient working people in agricultural production in our country. In the long years before the artificial nitrogen fertilizer industry was invented, most of the nitrogen source of agricultural production came from biological nitrogen fixation. Even with the highly developed nitrogenous fertilizer industry today, the total annual total amount of biological nitrogen fixation in the world is estimated at 175 million tons, which is about four times that of industrial nitrogen fixation. From the history of the entire agricultural development, even if we say that “there is no biological nitrogen fixation, there will be no agricultural production,” it will not be excessive. For example, from the requirements of maintaining ecological balance, maintaining soil fertility, preventing environmental pollution and saving energy costs, it is obviously not desirable to simply follow the path of “inorganic agriculture” or “oil agriculture.” Biological nitrogen fixation should still be agricultural production in the future The main nitrogen source.