The flow of energy in an ecosystem

Energy is the foundation of the ecosystem, and all life has the process of energy
and
. Without the flow of energy, there would be no life and no ecosystem. Flow flow is one of the important functions of ecosystem, and the flow and transformation of energy are subject to the first and second laws of thermodynamics, because thermodynamics is the science of studying the laws of energy transfer and energy form conversion.energy flows can be analysed at three levels: ecosystem, food chain and population. The energy flow analysis at the ecosystem level is estimated by the total number of individual populations at the same nutritional level, i.e. each population is attributed to a specific nutrient level (based on its primary feeding characteristics) and then the input and output values of each nutrient level's energy are accurately measured. This kind of analysis is found in aquatic ecosystems, because its boundaries are clear, closed and the internal environment is stable. Energy flow analysis at the food chain level is a link in the movement of energy from producer to top consumer, and when energy flows between several species along a food chain, measuring energy values at each link of the food chain can provide detailed and accurate information on the flow of energy at a specific point in the ecosystem. The energy flow analysis at the experimental population level is to control various unrelated variables in the laboratory to study the important environmental factors that affect energy loss and energy storage in the process of energy flow.we also introduce the concepts of the food chain, food web, nutrition level, ecological pyramid, etc. The energy fixed by plants is transmitted in the ecosystem through a series of feeding and feeding relationships called the food chain (food chains). The general food chain is4 to 5 , such as grass→ insects→ birds → snakes → eagles. But the relationship between feeding and feeding between organisms in ecosystems is complex, and this connection is like an invisible web that includes all living things, so that they have some direct or indirect relationship with each other, namely the food web ). In general, the more complex the food web, the stronger the ecosystem's ability to resist external interference and vice versa. There are two main food chains in any ecosystem, the grazing food chain ) and the debris food chain (detrital food chain ), which starts with living plants and animals, and the , which starts with dead organisms or rotting debris. In most terrestrial and shallow-water ecosystems, the rotting food chain is the most important, such as the plant biomass of a poplar forest excepting 6%which is taken by animals, and the remaining 94%which is broken down by the decomposer after dying and withering. A nutritional level (trophic levels ) refers to the sum of all biological populations at some point in the food chain, and each biological population is often placed at a determined nutritional level for convenience when analysing the energy flow of ecosystems. Producers are the first nutrition level, plant-eating animals are the second nutritional level, the third nutrition level includes all plant-eating animals as a carnivore, the general number of nutrition levels of an ecosystem is 3 to 5,. The ecological pyramid (ecological pyramids ) refers to the quantitative relationship between the various nutritional levels, which can be used in biomass units, energy units and individual units of quantity ,respectively, constitute biomass pyramids, energy pyramids and quantitative pyramids.