Respected Sir, Rk Naresh

Energy flows through ecosystems primarily in food chains and food webs, while chemicals (such as nutrients) cycle through ecosystems in biogeochemical cycles. Let's explore the differences between these two processes:

Energy is transferred between organisms in food webs from producers to consumers. The energy is used by organisms to carry out complex tasks. The vast majority of energy that exists in food webs originates from the sun and is converted (transformed) into chemical energy by the process of photosynthesis in plants. In a food chain, energy flows from the organism being eaten to the organism doing the eating. So, it flows from the producers to the consumers and finally to the decomposers. The consumers eat the producers, and the decomposers eat the dead and dying consumers. A food chain is a linear sequence of organisms through which nutrients and energy pass as one organism eats another. In a food chain, each organism occupies a different trophic level, defined by how many energy transfers separate it from the basic input of the chain. In an ecosystem, energy flows from producers to primary consumers to secondary and tertiary consumers. Food chains and food webs model this energy flow and these feeding relationships. Each step in a food chain is called a trophic level. Chemical nutrients and energy tend to flow in the same direction for most of an ecosystem. The big difference is that the chemical nutrients are ultimately recycled in the ecosystem while the energy is ultimately lost from the ecosystem to the universe at large. Energy in any ecosystem ultimately comes from the Sun. So, the energy that enters an ecosystem as sunlight eventually flows out of the ecosystem in the form of heat. In contrast, the matter in an ecosystem is continuously recycled as atoms are combined and recombined in different ways. Transfer of substances through trophic levels of ecosystem. Energy flows through, and ultimately out, of ecosystems and chemicals are recycled within ecosystems. Energy flows through an ecosystem and is dissipated as heat, but chemical elements are recycled. The ways in which an element or compound such as water moves between its various living and nonliving forms and locations in the biosphere is called a biogeochemical cycle.

Ecosystems are all about energy flow and cycling of chemicals. Here's a breakdown of how energy travels through food chains and webs, and how it differs from chemical movement:

Energy Flow in Food Chains and Webs:

• One-way Street: Energy enters the ecosystem as sunlight and gets captured by producers (plants) through photosynthesis. This transforms light energy into chemical energy stored in organic molecules.
• Feeding Frenzy: Consumers then take over, eating producers (herbivores) or other consumers (carnivores, omnivores). With each bite, energy is transferred, but not completely.
• Energy Loss: A big difference here is that energy gets lost at each transfer. Organisms use energy for survival, and the rest escapes as heat, unavailable for the next level. That's why only about 10% of energy gets passed on typically.
• Food Chains vs. Webs: Food chains are simplified linear models (grass > rabbit > fox), while food webs are more realistic, showing the interconnectedness of various feeders at different levels.

Chemical Flow in Ecosystems:

• Recycling Act: Unlike energy, chemicals cycle and reuse within the ecosystem. Think of it like a closed loop.
• Decomposer Delights: Decomposers, like fungi and bacteria, break down dead organisms and waste products. This releases nutrients back into the soil, where producers can take them up again.
• Chemical Transformations: Chemicals can change form as they move through the system. For example, nitrogen gas from the atmosphere gets converted by bacteria into a usable form for plants.

Key Differences

• Energy Flow: One-directional, with loss at each transfer.
• Chemical Flow: Cyclical, with reuse and transformations.

Analogy Time: Imagine a campfire. The sun's energy is like the logs you add, providing fuel. As the fire burns (organisms using energy), it releases heat (energy loss). But the ashes (chemicals) remain and can be used by plants (through decomposition) to grow new trees (producers), which eventually become firewood again.

So, energy keeps flowing in and dissipating, while chemicals are constantly circulating and changing forms within the ecosystem.

Dr Murtadha Shukur thank you for your contribution to the discussion

Energy flows through an ecosystem as it is transferred from one organism to another through the food chain, while nutrients are cycled within an ecosystem because they are constantly reused by different organisms, through processes such as decomposition and uptake by plants. Energy is transferred between organisms in food webs from producers to consumers. The energy is used by organisms to carry out complex tasks. The vast majority of energy that exists in food webs originates from the sun and is converted (transformed) into chemical energy by the process of photosynthesis in plants. Chemical nutrients and energy tend to flow in the same direction for most of an ecosystem. The big difference is that the chemical nutrients are ultimately recycled in the ecosystem while the energy is ultimately lost from the ecosystem to the universe at large. Energy in any ecosystem ultimately comes from the Sun. So, the energy that enters an ecosystem as sunlight eventually flows out of the ecosystem in the form of heat. In contrast, the matter in an ecosystem is continuously recycled as atoms are combined and recombined in different ways. Energy flows through an ecosystem and is dissipated as heat, but chemical elements are recycled. The ways in which an element or compound such as water moves between its various living and nonliving forms and locations in the biosphere is called a biogeochemical cycle. The energy flow takes place via the food chain and food web. During the process of energy flow in the ecosystem, plants being the producers absorb sunlight with the help of the chloroplasts and a part of it is transformed into chemical energy in the process of photosynthesis. A biogeochemical cycle is a pathway by which a chemical substance moves through the biosphere, lithosphere, atmosphere, and hydrosphere components of Earth. Thus, the flow of elements in each cycle from non-living to living and back to non-living is called bio-geo-chemical cycles. Energy is transferred between organisms in food webs from producers to consumers. The energy is used by organisms to carry out complex tasks. The vast majority of energy that exists in food webs originates from the sun and is converted (transformed) into chemical energy by the process of photosynthesis in plants. Primary producers use energy from the sun to produce their own food in the form of glucose, and then primary producers are eaten by primary consumers who are in turn eaten by secondary consumers, and so on, so that energy flows from one trophic level, or level of the food chain, to the next. In an ecosystem, energy flows from producers (plants) to primary consumers (herbivores) to secondary and tertiary consumers (carnivores). Food chains and food webs model this energy flow and these feeding relationships. Each step in a food chain is called a trophic level.