Ecology Concepts and Environmental Issues

• Ecology studies how living things interact with each other and their physical environment.
• Living things exhibit characteristics like Movement, Reproduction, Sensitivity, Growth, Respiration, Excretion, and Nutrition (MRS GREN).

Species, Ecosystems, and Niches

• A species is a group of organisms capable of reproducing fertile offspring.
• Members of a species share similar structural and behavioral traits.
• A population consists of members of the same species living and interacting in a specific area at the same time.
• Population size is determined by biotic (living) and abiotic (non-living) factors within the ecosystem.
• Abiotic factors influence the ecosystem type, the organisms present, and their population sizes.
• Biotic factors involve interactions between communities within the forest.
• A habitat is the place where an organism is found, comprising abiotic factors.
• A niche describes the role an organism carries out in its environment.
• No two species can occupy the same niche.
• A community encompasses interactions between all populations in a habitat.
• An ecosystem involves the interaction of abiotic and biotic factors within a given area.

Energy Flow in Ecosystems

• All energy in an ecosystem originates from the Sun.
• Plants capture sunlight and use photosynthesis to convert it into a transferable form of energy.
• Photosynthesis equation: Carbon Dioxide + Water --(Sunlight, Chlorophyll)--> Glucose + Oxygen
• Animals obtain energy by consuming other organisms and breaking down glucose.
• Producers, also known as autotrophs, perform photosynthesis and are self-feeding.
• Consumers obtain energy by feeding on other organisms.
• Herbivores consume plants, carnivores consume animals, and omnivores consume both.
• Decomposers break down dead material, making nutrients available.

Food Chains

• A food chain illustrates the transfer of energy from one organism to another, starting with a producer.
• Arrows in a food chain indicate the direction of energy flow through an ecosystem.
• Plants are producers; animals are primary, secondary or tertiary consumers.
• A primary consumer eats plants, a secondary consumer eats herbivores, and a tertiary consumer eats secondary consumers.
• An organism's position in a food chain is its trophic (feeding) level.
• Energy available decreases at each trophic level because organisms use energy for life processes.
• Typically, only about 10% of energy is transferred to the next level, limiting food chains to usually five or fewer trophic levels.

Food Webs

• Few organisms consume only one other organism for energy, and those that do are highly threatened.
• A food web is a network of interconnected food chains in a community, illustrating energy flow through the ecosystem.
• Consumers can occupy multiple trophic levels within a food web.

Relationships Between Living Things

• Communities exhibit various relationships between individuals; they engage in symbiosis
• Symbiosis include mutualism, commensalism, and parasitism.
• Mutualism benefits both species in the relationship.
• Commensalism benefits one species while neither harming nor helping the other.
• Parasitism benefits one species and harms the other.
• Human have altered food webs and species relationships due to increased population and food demands.
• Traditional farming, which involved a variety of plants and animals, shifted to large areas dedicated to single crops, leading to increased fertilizer and pesticide use.
• Intensive farming has resulted in habitat destruction, pollution, and reduced wildlife.

The Carbon Cycle

• Carbon is a key component of chemical compounds in living organisms.
• Plants obtain carbon from the atmosphere as carbon dioxide.
• Animals get carbon from plants or other organisms.
• The carbon cycle tracks carbon movement between the atmosphere and living things.
• During photosynthesis, plants use light and carbon dioxide to produce glucose, which is used to create starch, proteins, and other compounds.
• When animals consume plants, they digest and absorb carbon to create their own tissues.
• Fossilization occurs when carbon in dead organisms is trapped and compressed, forming fossil fuels like coal, oil, as well as natural gas.
• Respiration is the process where cells use oxygen to break down glucose into carbon dioxide and water, which are released as waste.
• Decomposition occurs when dead organisms and waste products are broken down, releasing stored carbon back into the environment for use by producers.
• Burning fuels like wood and coal releases carbon dioxide into the atmosphere through combustion.

Habitat Destruction

• Habitat destruction is caused by the need for increased area for food crop growth, also livestock production and housing.
• Habitat destruction is caused by over extraction of natural resources, pollution and climate change
• Early humans had a smaller environmental impact by gathering food and hunting in small groups.
• Agriculture enabled humans to support larger populations by modifying the environment for more food that led to ecosystem destruction.
• Deforestation can lead to species extinction and habitat erosion.

Pollution

• Uncontrolled human activities from population growth and industrialization have increased ecological imbalance.
• Pollution contaminates the Earth's environment via harmful substances.
• Pollutants contaminate the environmental like sewage water, harmful chemicals, and gases
• Biodegradable pollutants break down by biological agents.
• Non-biodegradable pollutants do not break down by biological agents.
• Types of pollution:
  • Air pollution from carbon particles, sulphur dioxide and CFC's
  • Water pollution from waste water and fertilizers
  • Soil pollution from polythene, plastic, fertilizers, pesticides and insecticides
  • Noise pollution from industries, transportation, entertainment and construction

Eutrophication

• Eutrophication is an excessive richness of nutrients in a body of water, frequently due to runoff from the land, which causes a dense growth of plant life and death of animal life due to lack of oxygen.
• Excessive nutrients from fertilizers are flushed from the land into bodies of water by rainwater.
• Algae blooms and grow on the surface of the water which prevents sunlight reaching other plants, these other plants die
• Plants that die are broken down in the water consumes oxygen
• The low oxygen levels in the water cause other animals living in the ecosystem to die
• Eutrophication is mainly caused by agriculture, the meat industry, and dairy processing.

Conservation

• A sustainable resource is produced as rapidly as it is removed from the environment.
• Restrictions were placed on collection of food, like Kina.
• Raw materials like metal ores and fossil fuels are non-renewable.
• Alternative sources of energy must be developed
• Biodiversity or Biological Diversity defines different populations in an ecosystem which defines healthiness
• A high biodiversity environment is a rain forest
• A low biodiversity environment is a crop of wheat

Maintain Biodiversity

• Reasons scientists tend to put for maintaining biodiversity.
  • Biodiversity is required for human use
    • Medicinal reasons: medicines can be harvested from plants and animals and potential unique chemicals will be lost will extinction
    • Food reasons: changing climate can affect 35 food source organisms humans rely on.
    • Genes from other organisms can be used to boost disease resistance.
  • Biodiversity to maintain nature
    • Removing essential keystone species can lead to irreversible ecosystem change.
    • As can be seen with the eating of kina by snapper
  • Biodiversity for survival
    • Long term survivability of species is important

Conservation Efforts

• Conservation maintains biodiversity.
• Biodiversity can be affected by habitat destruction, introduction of alien species, over harvesting, international trade in animals and plants, pollution, and climate change.
• These actions reduce the population of species and can cause them to struggle to survive.
• Species can can become endangered when a large amount of their population dies.

Zoos, National Parks and Marine Reserves

• Play and important role in conservation.
• Zoos perform education and captive breeding.
• National Parks consist of preserved habitats used to protect plants, animals, the environment and allow recreation.
• Marine reserves protect reserves from fishing and harvesting, which helps the population of fish continue to thrive.

Test your knowledge of ecological concepts, including niches, energy flow, and carbon cycling. Explore environmental issues such as habitat destruction, sustainable resources, and the impacts of agriculture. Assess your understanding of symbiotic relationships and conservation efforts.