Howdy! Today we will be discussing biogeochemical cycles more in depth. Biogeochemical cycles are also known as nutrient cycles, which may be a term that you are more familiar with.
Very quickly, we will go through the importance of nutrient cycles, the water cycle, the nitrogen cycle, the carbon cycle, the phosphorus cycle, and the sulfur cycle. So, why are nutrient cycles important? Well, nutrient cycles are vital for the functioning of all life on Earth. All matter on this Earth is conserved and recycled. Nutrient cycles are responsible for transforming elements from one form of matter into another, from one place to another, and can also store elements for later use.
They are absolutely vital for the proper functioning of ecosystems, and nutrient cycles can link elements and living organisms through the regulation and flow between different spheres. Nutrient cycles help transform nutrients from the biotic systems to abiotic systems. Biotic, or living systems, represent all life found in the biosphere and the nutrients that are found within all life. Abiotic, or nonliving systems, help us to understand how nutrients move between the living and nonliving world.
So examples of abiotic systems include the atmosphere, hydrosphere, lithosphere, and cryosphere. Energy flow within ecosystems is an important concept to understand. Energy comes from the sun. Producers, or plants, on our planet make energy usable.
Once it is usable, it can be respired through cellular respiration. Photosynthesis is the most important step along the way because it synthesizes energy from the sun and converts it into usable nutrients. Net primary production is how much is left after the plant gets what it needs and uses the rest of the energy for cellular respiration. Each trophic level uses and loses energy along the way.
Primary consumers eat the producers and convert the energy into biomass, and respire the remainder through cellular respiration. And this process occurs at each trophic level. An ecological pyramid can help to understand the energy efficiency at each trophic level and the remaining productivity. So, starting with the energy from the sun, primary producers absorb and transform energy into usable nutrients.
At each level, energy is lost in the form of heat as organisms respire. This is also why we have way less tertiary consumers compared with producers. The water cycle is probably the cycle you are all the most familiar with.
It starts with evaporation, transpiration, evapotranspiration, and sublimation, which are all processes where water is released into the atmosphere. Once there, it forms into clouds through the process of condensation. Once the clouds are heavy enough, water is then released through precipitation as either rain or snow.
From there, there is water runoff into freshwater storage or ocean storage. It can infiltrate and move through as groundwater, and ultimately the process starts all over again. The carbon cycle is one of the more important cycles to understand. Carbon moves from the atmosphere to plants.
Carbon, or CO2, is pulled from the air through photosynthesis. Carbon moves from plants to animals when animals consume plants and absorb carbon. Carbon moves from plants and animals into the soils when plants and animals die, their bodies or wood and leaves decay, bringing the carbon into the ground. Carbon can move from living things into the atmosphere. Creatures exhale CO2 into the atmosphere and carbon can move from fossil fuels into the atmosphere when fuels are burned.
mainly through industry and energy production. This is a major human contribution. Carbon moves from the atmosphere again into the oceans and the oceans and other bodies of water can absorb carbon from the atmosphere as well.
Carbon is then dissolved into the water and the process starts again. The nitrogen cycle is also a really important cycle to understand because nitrogen is one of the primary nutrients Nitrogen fixation is a conversion of atmospheric nitrogen into forms that are useful for plants, bacteria, etc. Nitrification is the process by which ammonia gets converted into nitrite or nitrate. Bacteria can also go through a process of denitrification where nitrate or nitrite is released back into atmospheric nitrogen. Assimilation occurs when plant roots absorb new forms of nitrogen, either nitrites or nitrates.
Ammonification occurs when organic nitrogen is converted into ammonia by bacteria involved in decomposition. Again, denitrification is when bacteria turns the decomposed matter back into nitrite, which is then released back to the atmosphere as a gaseous form of nitrogen, thereby repeating. The process.
The oxygen cycle occurs in a variety of ways. Oxygen is produced by sunlight and plant life and used by animals for respiration. It's used by combustion processes, oxidation, and decomposition. Respiration occurs because all animals use oxygen for respiration and we exhale CO2. Decomposition occurs when plants and animals die and they decompose.
This process uses up oxygen and releases carbon dioxide into the air. Rusting is also a process called oxidation, and this process causes metals to rust. It's also a process that uses up oxygen.
Combustion is the process by which fire is generated, and it also requires oxygen, along with heat and fuel. This process uses up oxygen and releases carbon dioxide into the atmosphere. The phosphorus and sulfur cycle are the slowest. Mostly through rain, weathering can cause rocks and stones to release phosphate ions. This inorganic phosphate is then distributed in soils and water.
Plants take up this inorganic phosphate from the soils. Once in the plant or animal, if the plant is eaten, the phosphorus is incorporated into organic cells creating organic phosphate. When the animals or the plants die, the organic phosphate goes back into the soil. Within the soil, organic forms of phosphate can be made available to plants by bacteria that break down organic matter into inorganic forms of phosphorus.
This process is known as mineralization. Phosphorus in soil can end up in the waterways and eventually the oceans. Once there, it can be incorporated into sediments over time, thus creating another form of inorganic phosphate.
Sulfur is one of the components that make up proteins and vitamins. Proteins consist of amino acids that contain sulfur atoms. Sulfur is important for the functioning of proteins and enzymes in plants and in animals that depend on plants for sulfur. Mineralization converts organic sulfur into hydrogen sulfide, an inorganic form of sulfur.
Oxidation is when hydrogen sulfide is converted to sulfate. This oxidation process can occur when microorganisms convert it for energy production. Reduction occurs in which sulfate is reduced to sulfide within plants. Incorporation involves the process of changing sulfide into organic compounds.
This process can include metal-containing derivatives. Microorganisms also have the ability to immobilize sulfur compounds, which ultimately results in subsequent incorporation of these sulfur compounds into the inorganic forms of sulfur. Here are a few weekly podcasts that you can listen to or choose from. that incorporate discussions of different types of nutrient cycles.