Introduction: Nitrogen Cycle
The biogeochemical cycles form the basis of nutrient and elemental chemical rotation between various biotic and abiotic components of the ecosystem. The Nitrogen cycle is one among several such elemental cycles. While many of us might be unaware of the abundance of nitrogen around us, the essential role that nitrogen plays in the atmosphere (78% of the Earth’s atmospheric composition), DNA structure (all bases; A, T, G, C are nitrogenous), proteins structures (all amino acids have nitrogen in their basic structure), etc can’t be overemphasized.
The nitrogen cycle exists between the atmosphere, hydrosphere, biosphere, pedosphere and geosphere through a perfectly knitted channel between microbes, plants, animals and abiotic factors. The diversity of members that constitute the nitrogen cycle is flawless. The essence of each of these members at a specific position in the cycle can be understood if one dives deep into the subject. When we say that microbes are irreplaceable in this cycle, we mean it.
Students are first introduced to the topic of the nitrogen cycle very early in their schooling, sometimes even before they enter high school. Still, the confusion and problems associated with the topic don’t seem to leave young students’ backs. Educators find it hard to explain as the topic is very extensive and there’s difficulty in simplifying all of its details.
To answer all of these questions, we have strived to gather some resources in this article. As you read, you’ll be portrayed with the basic issues that students face while learning about this topic. We’ll also provide some practical solutions to overcome those issues.. By the end, we’ll share why a virtual lab simulation will prove helpful not only for your students but also for you as an educator to deliver concepts more efficiently.
3 reasons why Nitrogen Cycle can be tricky to teach or learn
There are 3 major reasons why students are overwhelmed by the topic of the Nitrogen Cycle. Acknowledging these issues is the first step toward making the topic more approachable.
1. The topic is too theoretical
The topic of the nitrogen cycle often seems too philosophical. There’s a lot of theoretical dimension to the subject. Learning and memorizing different steps of the nitrogen cycle like Nitrogen fixation (N2 to NH3/NH4+ or NO3-), Nitrification (NH3 to NO3-), Assimilation (incorporation of NH3 and NO3- into biological tissues), Ammonification (conversion of organic nitrogen compounds to NH3), Denitrification (NO3- to N2) is one of the most difficult tasks for students. Without understanding the rationale behind these chemical conversions, students rote learn the equations and derive no substantial gains from the subject.
2. Failure to connect dots
When the roles of different types of biotic and abiotic factors at the different steps of the nitrogen cycle aren’t clear to students, remembering the names of those factors becomes a herculean task. Why nitrification/nitrifying bacteria are different from ammonification bacteria and fungi? Why can’t the same set of microbes serve all the functions in the cycle? Why can’t plants and animals fix atmospheric nitrogen? How are denitrification bacteria like Pseudomonas and Clostridium different from nitrification bacteria like Nitrosomonas and Nitrobacter?
Without understanding the core concepts underlying the nitrogen cycle, connecting the dots between different steps and organisms is not possible.
3. Lack of interactive learning tools
Since the different steps of the nitrogen cycle occur in the world around us, students long to practically observe the phenomenon in nature. We understand that teachers and educators try to make the subject interesting by incorporating colorful, bright figures and illustrations, but they sometimes seem inadequate. Since field trips and lab experiments to isolate each of these different types of bacteria aren’t always feasible, students are crunched under the burden of extensive theory with no fun-filled interactive teaching sessions.
5 ways to make Nitrogen Cycle a more approachable topic to understand
To address the issues encountered while teaching Nitrogen Cycle, educators can engage the under-listed solutions in their next classes. These can shed light on how to handle each issue that students encounter. They will not only make lessons clearer and simpler for your pupils to understand, but they will also make teaching easier for educators like you.
1. Solidify the fundamental and core concepts
Our first suggestion to educators for making the topic of the nitrogen cycle engaging and interesting is to simplify and strengthen the core concepts of the subject. The information should come freely flowing to students rather than a sudden mind-boggling sum of chemical equations.
Students tend to believe that cramming chemical equations of different steps of the nitrogen cycle is a flex. But it isn’t so! Educators can try some of the under-listed solutions to strengthen the core concepts so that students can think and devise the equation themselves without the need to cram those equations.
Discuss the relative abundance of nitrogen in the atmosphere (which is very vast). Then discuss the incompetence of plants, animals and other organisms to fix that nitrogen for their metabolic needs. Then introduce the idea of a certain type of organism that can fix that nitrogen, i.e. nitrogen-fixing bacteria. Explain the presence and significance of the “nitrogenase enzyme” that is present only in a few prokaryotic bacterial life forms. When your students understand this, they’ll know that only a very narrow range of organisms can mediate the first step of the nitrogen cycle, i.e., nitrogen fixation. Both the equation and the organisms involved will become easier to remember after the concept is made clear to the students.
2. Take more field trips to explain important aspects of the nitrogen cycle
Due to the relevance of the nitrogen cycle to Earth’s basic functioning, taking your students on field trips can enable them to observe the different processes of the nitrogen cycle firsthand. You can make the concepts crystal clear by organizing some ideas and plans beforehand.
You can take them to agricultural fields where nitrogenous fertilizers are used. Explaining to them the artificial process of nitrogen fixation can become clearer here. You can emphasize the contributions of 2 German scientists; Fritz Haber and Carl Bosch, who developed this method of conversion of non-reactive atmospheric nitrogen (N2 gas) into ammonia (NH3). The process is popularly called the Haber-Bosch process for honoring their contributions. Using high pressures and temperatures, ammonia is produced from gaseous nitrogen at the industrial level. This becomes immensely useful in the form of nitrogen fertilizers used in agricultural fields.
You can take them to legume fields and show the nodules in their roots. Nodulating nitrogen-fixing bacteria are found abundantly in the roots of soybean, groundnuts, clover, peas, etc. The concepts of nitrogen fixation can become clearer through this small activity.
You can plan a trip to some river basin. . Unabated use of chemical fertilizers has wreaked havoc in the river basins. Make your students observe the phenomenon of eutrophication; the process of overgrowth of phytoplanktons and algae due to the excessive release of nutrients (mainly nitrogen and phosphorus) into the water bodies. Since farmers have been exploiting these nitrogenous fertilizers to get higher yields, the agricultural run-off and bleached chemicals reach the local water bodies, rivers and eventually river basins. This promotes heavy planktonic growth which makes these bodies appear green in color. The real tragedy begins when these planktons die off and the microbes start feeding on them which rapidly lowers the levels of dissolved oxygen (DO) in the bottom zones of water bodies. This negatively affects aquatic life and leads to the “creation of dead zones”; zones with little or no aquatic life.
Simplify the list of organisms mediating the nitrogen cycle
Ease the work of your students by providing simple flow charts showing the roles of organisms at the different steps of the nitrogen cycle. The scientific names of the various bacteria, fungi, etc are sometimes challenging to memorize. Demonstrating all of them in the form of infographics and flowcharts might make it catchy for students.
Figure: A flowchart showing different organisms involved in the nitrogen cycle. Image Source
4. Make them see the prospects
Since the world is currently handicapped by this eutrophication mess, we need more scientists who better understand the biogeochemical cycles, especially the nitrogen cycle. Conservationists and microbiologists working on the restoration of water bodies relate their research to the nitrogen cycle and its core concepts. Agricultural biotechnologists all over the world are trying to decipher different types of nitrogen-fixing bacteria and up-regulate the enzymatic activity of nitrogenase enzymes. This topic has a multitude of real-world applications and if students wish, they can innovate a lot in this field.
5. Use virtual lab simulations
Biogeochemical cycles including carbon cycles are challenging theoretical concepts to teach, therefore, we at Labster have a solution for you. You can utilize Labster's Nitrogen Cycle simulation in your next class to close the gaps in the available teaching resources and address the lack of visually engaging video graphical possibilities in the educational space.
We offer a wonderful opportunity to your students where they can virtually assume the role of a farmer who aims to increase his yields while minimizing the negative environmental impacts. With our gamification elements, they can play with the various parameters of food production like choosing crops for crop rotation, choosing different amounts of fertilizer, etc. They can time travel 4 years ahead and see the effects of their choices. Since this is a virtual engagement, they don’t need to worry if the nitrogen cycle is any time disturbed. They can redo the entire activity as many times as they want to.
Using our virtual learning platform where educators can use different methods of interactive and immersive instruction, we believe we can together strengthen the fundamental concepts for future scientists in the making.
Figure: Interactive snippet from the Nitrogen Cycle simulation from Labster showing the activity where students can actively engage in their virtual agricultural field. The simulation is available for High School courses.