Atmosphere and Industrial fixation
Nitrogen in
atmosphere
Nitrogen
fixation
Protoplasm
(green plants)
Protoplasm
Ammonification
Ammonia
Nitrification
Fig. 14.6: Nitrogen-cycle in nature
adds
is the
Answers
Answer:
Making up 78 percent of the air, nitrogen is an essential element to life on Earth. It’s a component of all proteins and can be found in all living systems. Nitrogen compounds are also present in organic materials, foods, fertilizers, explosives and even poisons.
As in the air, nitrogen occurs naturally in organic form in the soil, constantly cycling between the soil and the air. This ‘nitrogen cycle’ is necessary to convert unavailable atmospheric nitrogen to plants available ammonia and nitrates ions. Microbes and bacteria in the soil (nitrogen fixators) ‘fix’ nitrogen directly from the atmosphere and convert it into ammonium and nitrates, e.g. compounds available to plants. Plants and algae use those nitrates to build up the bases needed to construct DNA, RNA and all amino acids necessary for proper functioning of the animal metabolism which obtain nitrogen by consuming plants.
Seeking for higher yields, farmers add various chemical and biological fertilizers to the soil. Actually, to achieve yields expected in today’s modern farming, many crops require additional N fertilization, thus making it the most limiting nutrient in crop production.
Since scientists managed to transform nitrogen gas into a digestible form of ammonia, the era of widespread fertilizer use in croplands has begun. Nitrogen has many positive effects on farm and industrial production systems, human nutrition and food security. Without it, plants are weaker and smaller.
Although nitrogen is crucial for plant growth, farmers need to be very careful when applying nitrogen into the soil. It can be easy lost to the environment due volatilization, denitrification, leaching due to excessive rainfall, evaporation and lost by runoff. Losses influence the ecosystem, soil characteristics, cropping pattern, fertilizer techniques and overall farm production management.
Answer:
Nitrogen Cycle Definition
“Nitrogen Cycle is a biogeochemical process which transforms the inert nitrogen present in the atmosphere to a more usable form for living organisms.”
Furthermore, nitrogen is a key nutrient element for plants. However, the abundant nitrogen in the atmosphere cannot be used directly by plants or animals. Read on to explore how the Nitrogen cycle makes usable nitrogen available to plants and other living organisms.
What is Nitrogen Cycle?
Nitrogen Cycle is a biogeochemical process through which nitrogen is converted into many forms, consecutively passing from the atmosphere to the soil to organism and back into the atmosphere.
It involves several processes such as nitrogen fixation, nitrification, denitrification, decay and putrefaction.
The nitrogen gas exists in both organic and inorganic forms. Organic nitrogen exists in living organisms, and they get passed through the food chain by the consumption of other living organisms.
Inorganic forms of nitrogen are found in abundance in the atmosphere. This nitrogen is made available to plants by symbiotic bacteria which can convert the inert nitrogen into a usable form – such as nitrites and nitrates.
Nitrogen undergoes various types of transformation to maintain a balance in the ecosystem. Furthermore, this process extends to various biomes, with the marine nitrogen cycle being one of the most complicated biogeochemical cycles.
Stages of Nitrogen Cycle
Process of Nitrogen Cycle consists of the following steps – Nitrogen fixation, Nitrification, Assimilation, Ammonification and Denitrification. These processes take place in several stages and are explained below: