Definition of Ecosystem
An ecosystem is an ecological system that is formed by the inseparable reciprocal relationship between living things and their environment. An ecosystem can also be said to be a unified whole and comprehensive order between all the elements of the living environment that influence each other. An ecosystem is an amalgamation of each biosystem unit involving mutual interactions between organisms and the physical environment so that the flow of energy leads to a certain biotic structure and a material cycle occurs between organisms and inorganic organisms. The sun is the source of all existing energy.
In an ecosystem, organisms in a community develop together with the physical environment as a system. Organisms will adapt to the physical environment, otherwise organisms also affect the physical environment for the purposes of life. This understanding is based on the Gaia Hypothesis, namely: “organisms, especially microorganisms, together with the physical environment produce a control system that maintains conditions on earth suitable for life”. This leads to the fact that the chemistry of the atmosphere and the earth is very controlled and very different from that of the other planets in the solar system.
The presence, abundance and distribution of a species in an ecosystem is determined by the level of availability of resources and the conditions of chemical and physical factors that must be within the range that can be tolerated by the species, this is what is called the law of tolerance.
For Example: Panda has a wide tolerance for temperature, but has a narrow tolerance for its food, namely bamboo.
Thus, pandas can live in an ecosystem under any conditions as long as there is bamboo in that ecosystem as a food source. Unlike other living things, humans can widen their tolerance range because of their ability to think, develop technology and manipulate nature.
Understanding Ecosystem According to Experts
The definition of an Ecosystem was first put forward by a British ecologist named AGTansley in 1935, although the concept is not a new concept. Prior to the late 1800s, official statements about terms and concepts related to ecosystems began to appear quite interestingly in the ecological literature in America, Europe, and Russia.
Some definitions of ecosystems can be described as follows:
1. Ecosystem is an ecological unit in which there is a relationship between structure and function. The structure referred to in the definition of ecosystem is related to species diversity. Ecosystems that have complex structures have high species diversity. While the term function in the definition of ecosystem according to AGTansley relates to the cycle of matter and energy flows through ecosystem components.
2. Ecosystem is an arrangement of the elements of the environment and life (biotic and abiotic) as a whole and comprehensively, which influence and depend on one another. Ecosystems contain a diversity of species in a community with its environment that functions as a unit of the interaction of life in nature (Ministry of Forestry, 1997)
3. Ecosystem, which is a complex unitary arrangement in which habitats, plants and animals are considered as a unified whole, so that all of them will become part of the chain of material cycles and energy flows (Woodbury, 1954 in Setiadi, 1983).
4. Ecosystem is the basic functional unit in ecology which includes organisms and their environment (biotic and abiotic) and between them influence each other (Odum, 1993).
5. Ecosystem, which is a comprehensive unified order between all elements of the environment that influence each other (Environmental Law 1997)
6. Ecosystem, which is an ecological system formed by the reciprocal relationship between living things and their environment (Soemarwoto, 1983)
Components in Ecosystem
An ecosystem is composed of two main components, namely:
1. Abiotic components
Abiotic or non-living components are physical and chemical components that are the medium or substrate in which life takes place, or the environment in which life occurs. Most abiotic components vary in space and time. Abiotic components can be organic matter, inorganic compounds, and factors that affect the distribution of organisms.
Abiotic components are ecosystem components consisting of non-living things or inanimate objects, including:
1. Soil
Physical properties of soil that play a role in the ecosystem include texture, maturity, and water holding capacity.
2. Water
The supply of water on the surface of the soil will affect the life of plants and animals. Important things in the water that affect the life of living things are water temperature, water mineral content, salinity, water flow, evaporation, and water depth.
3. Air
Air is an abiotic environment in the form of gases in the form of an atmosphere that surrounds living things. Oxygen, carbon dioxide, and nitrogen are the most important gases for living things.
4. Sunlight
Sunlight is the main source of energy for life on this earth. One of them as the main factor needed in the process of photosynthesis.
5. Temperature or temperature
Every living thing requires an optimal temperature for metabolic activities and their reproduction.
2. Biotic components
Biotics is a term that is usually used to refer to living things (organisms). Biotic components are components that make up an ecosystem other than abiotic components (inanimate)
Biotic components are ecosystem components consisting of living things which include plants, animals, and humans.
Based on the role biotic components in the ecosystem can be divided into three, namely:
A. Producers
are living things that can make their own food with the help of sunlight through the process of photosynthesis.
Example: all green plants
B. Consumers
are living things that cannot make their own food and use the food produced by producers either directly or indirectly.
Example: animals and humans
Based on the level of consumers are divided into four, namely:
1. I/primary consumers are consumers/living things that eat producers
Example: herbivores/plant-eating animals
2. Second/secondary consumers are consumers/living things that eat consumers I.
Example: carnivores/meat-eating animals
3. Third/tertiary consumers are consumers/living things that eat consumers II
Example: omnivores/animals that eat everything.
4. The top consumer is the last consumer or animal that ranks at the top of the eating event.
3. Decomposer
Decomposers are organisms that break down organic matter from dead organisms. Decomposers are also called macro consumers (saprotrophs) because the food they eat is larger. Decomposing organisms absorb some of the decomposition products and release simple materials that can be reused by producers. The decomposers are bacteria and fungi. There are also decomposers called detritivores, which are decomposers that eat the remains of organic matter, for example, woodlice. There are three types of decomposition, namely:
1. aerobic: oxygen is an electron acceptor/oxidant
2. anaerobic: oxygen is not involved. Organic matter as electron acceptor/oxidant
3. fermentation: anaerobic but oxidized organic matter is also an electron acceptor. These components are in one place and interact to form an orderly ecosystem. For example, in an aquarium ecosystem, this ecosystem consists of fish as heterotrophs, aquatic plants as autotrophs, plankton floating in the water as decomposers, while abiotic components include water, sand, rocks, minerals and oxygen dissolved in water.
Decomposers, also known as reducible, are micro-organisms that can break down other creatures into nutrients.
Example: bacteria and fungi.
Food Patterns in Ecosystems
Living things can meet their food needs by producing their own food or obtaining it from outside.
Autotrophic organisms
Autotrophs are derived from the Greek words autos meaning self and tropes meaning food. So autotrophs are organisms that can make their own food by utilizing organic materials found in their environment with the help of chlorophyll and the main energy in the form of solar radiation. Therefore, organisms that contain chlorophyll are included in autotrophs and are generally green plants. Examples are mosses, ferns, seed plants. Plants in the ecosystem are domiciled as producers/producers.
Heterotrophic Organisms
Heterotroph comes from the word heteros meaning other and thorpe meaning food. So heterotrophs are organisms that get food from other creatures. In the ecosystem, they act as consumers and decomposers.