Lesson 3 - Changing Ecosystems PDF

Entry Card What have you noticed? How do land ecosystems change? o An ecosystem can change over time. Change usually happens so gradually that you might not notice the differences from day to day. Open your book and answer the following: (5 mins - Group) How do land ecosystems change? o T...

Entry Card What have you noticed? How do land ecosystems change? o An ecosystem can change over time. Change usually happens so gradually that you might not notice the differences from day to day. Open your book and answer the following: (5 mins - Group) How do land ecosystems change? o The change in the pond you just observed is an example of ecological succession. o Ecological succession is the process of one ecological community gradually changing into another. o Ecological succession occurs in a series of steps.. For example, small plants usually grow first. Larger plants, such as trees, usually grow last. o The final stage of ecological succession in a land ecosystem is a climax community-a stable community that no longer goes through major ecological changes. There are 2 types of ecological succession Ecological Ecological Ecological succession succession in areas succession in new where existing areas of land with ecosystems have little or no soil or been disturbed or vegetation. destroyed Ex: Primary Secondary Ex: 1. Forestland cleared 1. Lava flow. Succession Succession hundreds of years ago. gradually grew 2. Sand dune. back to a climax 3. Exposed rock. forest community of beech and maple trees. ATL Skills – (Thinking) Open your book and find the following: (10 mins - Individual) Write a summary of your understanding in a handmade poster Explore how an ecosystem Explore how secondary changes after a volcanic eruption succession can occur In conclusion Ecosystems change with time due to primary and secondary succession (10 mins – Individual Activity) How do aquatic ecosystems change? o Like land ecosystems, freshwater ecosystems change over time in a natural and predictable process. This process is called aquatic succession. o Observe how freshwater ecosystems change over time. How do aquatic ecosystems change? o As you just learned, sediments can build up at the bottom of bodies of water and become soil. o Sediment is any material that is broken down by the process of weathering and then transported by wind, water, or gravity. o Sediments are usually transported by water. o Runoff can move sediment into streams and other water passages. o How do you think this process affects populations of aquatic organisms? How do you think this process affects populations of aquatic organisms? How do you think this process affects populations of aquatic organisms? o Too much sediment can damage stream habitats, clog waterways, and cause flooding. o Negative environmental impacts of sedimentation include habitat loss. o Change in available nutrients, and coastline alteration. Sediment that is suspended in water may reduce visibility and make it difficult for animals to find food. o It may also prevent light from reaching plants that need sunlight for food. o Sediment that has collected on the bottoms of rivers and streams may cover habitats of fish or other animals.  Homework ATL Skills (Research) How do changing ecosystems affect populations? o The ecosystem operates under dynamic equilibrium, which describes the balance between different parts of the ecosystem. o The change in environments can lastfor years. After such a change happens, the balance is lost and individual organisms of a species might not be able to find the resources they need to survive. o These changes may disrupt all areas of the ecosystem. How do changing ecosystems affect populations? o Effects of Change from Natural disruptions, such as forest fires, floods, volcanic eruptions, and disease, can cause massive amounts of damage to an ecosystem. o These sudden changes may make it difficult for organisms to adapt. o Some disruptions, like mountain formation, may not happen suddenly but over many years. o In some cases, these changes have benefits, such as control the size of populations or allow new growth of plant life.