nitrogen fixation

简明释义

氮固定

英英释义

例句

1.Farmers often use legumes because they enhance the nitrogen fixation in the soil.

农民们常常使用豆科植物，因为它们能增强土壤中的氮固定。

2.Understanding nitrogen fixation can help improve crop yields and soil health.

理解氮固定可以帮助提高作物产量和土壤健康。

3.The process of nitrogen fixation is essential for converting atmospheric nitrogen into a usable form for plants.

氮固定的过程对于将大气中的氮转化为植物可用的形式至关重要。

4.The study of nitrogen fixation is crucial for sustainable agriculture practices.

研究氮固定对可持续农业实践至关重要。

5.Certain bacteria are responsible for nitrogen fixation in the root nodules of leguminous plants.

某些细菌负责在豆科植物的根瘤中进行氮固定。

作文

Nitrogen is one of the most abundant elements in the atmosphere, making up about 78% of the air we breathe. However, despite its abundance, nitrogen in its gaseous form (N2) is not directly usable by most living organisms. This is where the process of nitrogen fixation (氮的固定) comes into play. Nitrogen fixation refers to the conversion of atmospheric nitrogen into a form that can be utilized by plants and other organisms, primarily ammonia (NH3). This process is crucial for the growth of plants, as nitrogen is an essential nutrient that plays a vital role in the synthesis of proteins, nucleic acids, and other cellular components.There are two primary ways in which nitrogen fixation occurs: biological and abiotic. Biological nitrogen fixation is carried out by certain bacteria and archaea, some of which have symbiotic relationships with plants, particularly legumes. These microorganisms possess an enzyme called nitrogenase, which enables them to convert atmospheric nitrogen into ammonia. For instance, rhizobia are bacteria that form nodules on the roots of leguminous plants, allowing them to fix nitrogen effectively. This symbiotic relationship benefits both parties: the plant receives a readily available source of nitrogen, while the bacteria gain carbohydrates and a protective environment from the plant.On the other hand, abiotic nitrogen fixation occurs through natural processes such as lightning or industrial methods like the Haber-Bosch process. Lightning provides enough energy to break the strong triple bond of N2 molecules, allowing them to react with oxygen in the atmosphere to form nitrogen oxides. These compounds eventually settle on the ground during rainfall, enriching the soil with nitrogen. The Haber-Bosch process, developed in the early 20th century, synthesizes ammonia from atmospheric nitrogen and hydrogen gas under high temperatures and pressures. This method revolutionized agriculture by providing a synthetic source of nitrogen fertilizers, significantly increasing crop yields.The importance of nitrogen fixation cannot be overstated. Without this process, the nitrogen cycle would be disrupted, leading to nutrient deficiencies in plants and subsequently affecting the entire food chain. In agricultural systems, the use of nitrogen fixation, particularly through crop rotation with legumes, is a sustainable practice that enhances soil fertility and reduces the need for chemical fertilizers. Moreover, understanding nitrogen fixation has implications for environmental sustainability, as excessive use of synthetic fertilizers can lead to problems such as water pollution and greenhouse gas emissions.In conclusion, nitrogen fixation (氮的固定) is a fundamental ecological process that allows for the conversion of inert atmospheric nitrogen into biologically available forms. Whether through biological means involving symbiotic relationships with bacteria or through abiotic processes like lightning and industrial production, nitrogen fixation plays a critical role in supporting life on Earth. As we continue to face challenges in food production and environmental sustainability, recognizing the significance of nitrogen fixation will be essential for developing effective agricultural practices and ensuring the health of our ecosystems.

氮是大气中最丰富的元素之一，约占我们呼吸的空气的78%。然而，尽管氮的含量丰富，但以气态形式存在的氮（N2）对大多数生物而言并不可直接利用。这就是氮的固定（nitrogen fixation）过程发挥作用的地方。氮的固定指的是将大气中的氮转化为植物和其他生物可利用的形式，主要是氨（NH3）。这一过程对于植物的生长至关重要，因为氮是合成蛋白质、核酸和其他细胞成分的重要营养素。氮的固定主要有两种方式：生物性和非生物性。生物性氮的固定是由某些细菌和古菌进行的，其中一些与植物，特别是豆科植物形成共生关系。这些微生物具有一种叫做氮酶的酶，使它们能够将大气中的氮转化为氨。例如，根瘤菌是形成在豆科植物根部结节的细菌，使它们能够有效地固定氮。这种共生关系使双方受益：植物获得了可用的氮源，而细菌则从植物中获得碳水化合物和保护环境。另一方面，非生物性氮的固定通过自然过程如闪电或工业方法如哈伯-博施法进行。闪电提供足够的能量来打破N2分子的强三重键，使其与大气中的氧反应生成氮氧化物。这些化合物最终在降雨时沉降到地面，丰富土壤中的氮。哈伯-博施法是在20世纪初开发的，从大气中的氮和氢气在高温高压下合成氨。这一方法彻底改变了农业，通过提供合成氮肥，大幅提高了作物产量。氮的固定的重要性不容小觑。如果没有这一过程，氮循环将受到干扰，导致植物缺乏营养，从而影响整个食物链。在农业系统中，利用氮的固定，特别是通过与豆科植物轮作，是一种可持续的实践，可以增强土壤肥力，减少对化肥的需求。此外，理解氮的固定对环境可持续性也有重要意义，因为过度使用合成肥料可能导致水污染和温室气体排放等问题。总之，氮的固定（nitrogen fixation）是一个基本的生态过程，允许将惰性的大气氮转化为生物可用的形式。无论是通过涉及与细菌的共生关系的生物方式，还是通过闪电和工业生产等非生物过程，氮的固定在支持地球生命方面发挥着关键作用。随着我们继续面临粮食生产和环境可持续性的挑战，认识到氮的固定的重要性对于制定有效的农业实践和确保生态系统的健康至关重要。