Railway Science (Environment – Ecosystem & Ecology)

Overall, only about 10 percent of the energy stored as biomass in a trophic level is passed from one food level to the next. This is called “the 10 percent rule”. The available energy level at a particular trophic level is 10 times greater at the next trophic level.
Hence, if the energy level at the fourth trophic level is 10 KJ, then the energy at a third level trophic level is 10 times greater than the previous level i.e. 10 × 10= 100 KJ. The second trophic level has 1,000 KJ energy and the first trophic level (producer) has the energy of 10,000 KJ.

Green plants capture about 1% of the solar energy that falls on leaves for the process of photosynthesis. Each trophic level has a certain mass of living material at a particular time called the standing crop. The standing crop is measured as the mass of living organisms (biomass) or the number in a unit area.

Ten percent law of energy transfer - Given by Lindemann in 1942. This law states that only 10 percent of energy in a food chain out of the total energy is transferred from one trophic level to another. The rest of the energy is utilized for other metabolic processes and some are released as heat.

Self-sustaining ecosystem: maintenance of an ecosystem itself or naturally. i.e., A system that maintains itself by its own independent efforts. Sir Arthur G. Tansley gave the term Ecosystem. Ecosystem: The interactions that take place within a given space between biological and non-biological elements.

National Mission for Sustaining the Himalayan Ecosystem: Launched - June 2010. Objective - To develop a sustainable national capacity to continuously assess the health status of the himalayan ecosystem.
The Government of India launched the NAPCC on 30thJune, 2008 outlining eight national missions on climate change.
These include - National solar mission, National mission for enhanced energy efficiency, National mission on sustainable habitat, National water mission, National mission for sustaining the himalayan ecosystem, National mission for a green India, National mission for sustainable agriculture and National mission on strategic knowledge for climate change.

Ecology is the study of organisms and how they interact with the environment around them. The five levels of ecology - Organism, population, community, ecosystem, and biosphere.
Charles Darwin - Known for his contributions to evolutionary biology. Eugene Odum (American biologist) - Known for his pioneering work on ecosystems.
Eugenius Warming - A Danish botanist and a main founding figure of the scientific discipline of ecology.

Biotic Factors: All living organisms present in the ecosystem. Examples - Animals, plants, trees, grass, bacteria, moss, molds. Abiotic Factors: All non-living components present in the ecosystem. Examples - Sunlight, water, air, humidity, temperature, soil, minerals, wind.

This law states that only 10 percent of energy in a food chain out of the total energy is transferred from one trophic level to another.

This is an eco-friendly practice because it allows the leaves to decompose naturally and return their nutrients to the soil. This helps to improve the fertility of the soil and reduce the need for chemical fertilizers.

This law is known as the 10% energy law and was proposed by Raymond Lindeman.