Changes in an Ecosystem

1. Changes in an Ecosystem Ms. Newton

2. Changes in Ecosystems • Many factors can cause changes in an ecosystem including: • Climate • Human Activity/Interaction • Non Native (non indigenous) Species • Changes in populations

3. Change in Ecosystems - Climate • As climate changes, some species will relocate to new areas creating a new Ecosystem in new Area. • If a population is unable to relocate, a change in climate could mean extinction. • Extinction of some species = potential elimination of an entire ecosystem

4. Change in Ecosystems- Humans • Humans can drastically alter an organism’s ecosystem • Urban Development (building new homes) • Pollution (oil spills, burning fossil fuels, pesticide run off) • Deforestation – (cutting down forests)

5. Ecosystem Change – Non Native Species • When new species are introduced to an area (usually by humans), it can have a major impact on the ecosystem. • Example – Pythons in Florida – Wiping out some ecosystems. No natural predators.

6. Ecosystem Changes - Populations • Populations will grow and decrease naturally in an ecosystem. • Food, water, shelter, space are main factors in population change • When food is scarce, certain populations decrease. When food is abundant – certain populations increase. This is true on each trophic level of the food chain.

7. Factors that impact population growth • Limiting Factors: Limiting factors are things that prevent a population from growing any larger • Availability of Food, Water, Shelter • Space • Competition for resources • Predation • Disease

8. Adapting to Change • Adaptation – changing to better fit your environment • Populations have the ability to change in order to survive in a changing environment. • When change occurs animals can either adapt, move, or become extinct. • We will get deeper into adaptations in a few days.

9. Ecosystem Cycles • Within an Ecosystem you will find 3 main cycles necessary for survival • Water Cycle • Nitrogen Cycle • Carbon Cycle

10. Water Cycle • Water Cycles through Earth Constantly. The water cycle involves many processes: evaporation/transpiration  Condensation  Precipitation  Infiltration/Percolation  Run Off

11. Water Cycle • The water cycle provides fresh water to plants and animals in an ecosystem. • Plants need water to conduct photosynthesis – the process in which plants use carbon dioxide and water to make sugar for energy. • Animals need water for basic cellular function as well.

12. Carbon Cycle • Carbon is one of the most important elements found on Earth. Its in every living thing.

13. How does carbon get cycled through an ecosystem? • Plants use Carbon dioxide from the air to create food. • When that plant is eaten, the stored carbon is broken down and is now in the animal’s system. • The animal breathes out carbon dioxide and it is released back into the atmosphere. • If the animal dies, the carbon is broken down and also released back into the atmosphere.

14. Carbon Cycle • Carbon is also released into the atmosphere by the burning of fossil fuels

15. Nitrogen Cycle • Nitrogen is the most common gas found in the earth's atmosphere. It is necessary for plant growth. In fact, it's necessary for the survival of all ecosystems • Nitrogen is found naturally – atmosphere, animal waste, and dead organisms.

16. Nitrogen Cycle • Nitrogen fixing is when bacteria found in soil and roots of plants convert nitrogen into a substance that can be used (Nitrates, Nitrites, and Ammonia). • Once “fixed”, nitrogen can be used by plants and then nitrogen is passed on to animals when the plants are eaten. • Nitrogen can also be “fixed” by lightning

17. Nitrogen Cycle • Nitrogen is “released” back into an ecosystem in urine/waste and when an animal dies

18. Relationships • Different organisms interact with each other and their environment. • Competition occurs when organisms in an ecosystem try to get the same resources (deer activity) • Coexistence occurs when organisms do not compete for the same resources since they rely on different resources for survival.

19. Predator Prey Relationships • Predation is when one animal hunts, kills, and eats another. • The animal that is the hunter is the predator. • The animals that are killed and eaten are called Prey. • Predator Prey relationships balance an ecosystem.

20. Other Relationships • Symbiosis • A close relationship between two different species of organisms living together • Mutualism • Commensalism • Parasitism

21. Mutualism • Mutualism is a symbiotic relationship where BOTH species BENEFIT. • Example: Ox Pecker and Rhino • Oxpeckers eat insects off the rhino. Rhino benefits by having the insects removed.

22. Commensalism • Commensalism – a symbiotic relationship which one species benefits without benefiting or harming the other organism. • Barnacles on a whale. Barnacles use the whale as transportation and do not help or harm the whale.

23. Parasitism • Parasitism is a relationship between a parasite and its host. The parasite usually harms the host by taking away nutrients but usually does not kill the host. • Example: Ticks and Dogs

24. Key Terms – Copy into your journal • Autotrophs - Organisms that produce their own food through photosynthesis. • Consumers - Organisms that consume other organisms for food. • Decomposers - Organisms that break down the remains of plants and animals. • Energy pyramid - The flow of energy from the producer through the various consumers. • Food webs - Diagrams illustrating the interaction of organisms in an ecosystem. • Heterotrophs - Organisms that consume autotrophs or other heterotrophs for food and use their energy. • Producers - Organisms that use photosynthesis and create their own food. • Trophic level - Each level in an energy pyramid.