2. Ecosystems and Ecology

2.1 Species and populations

Significant ideas:

A species interacts with its abiotic environment, and its niche is described by these interactions.
Populations change and respond to interactions with the environment.
All systems have a carrying capacity for a given species.

Resources:

Power points	Case Studies	Activities	Useful Links
Species and populations t2.1 Application and Skills	Competition in a rocky shore	Mosquito seasonality activity	Niche-Bozeman Science
Populations Dynamics		Yellowstone National Park Wolves project	r and K selection-Bozeman Science

2.2 Communities and Ecosystems

Significant ideas:

The interactions of species with their environment result in energy and nutrient flow.
Photosynthesis and respirations play a significant role in the flow of energy in communities.
The feeding relationships in as system can be modelled using food chains, food webs and ecological pyramids.

Resources:

Power points	Case Studies	Activities	Useful Links
T2.2 Communities and Ecosystems T 2.2 Applications and Skills	Mystery in Alaska: Why have all the Sea Lions gone? Effects of fishing on the food web structure How Whaling Affects the Ecosystem The hidden life of kelp: How sea otters, urchins and starfish make ocean forests	Panama Food Webs Project: Modeling Food Webs in Darién, Panama Darien Food webs cards	The 10% energy rule video Bioaccumulation and Biomagnification Animation 2 Amoeba Sisters: Biomagnification and the Trouble with Toxins

2.3 Flows of energy and matter

Significant ideas:

Ecosystems are linked together by energy and matter flows.
The Sun's energy drives these flows and humans are impacting the flows of energy and matter both locally and globally

Resources:

Power points	Case Studies	Activities	Useful Links
Flows of energy and matter T 2.3 Applications and Skills		Determining GPP and NPP of a wheatgrass ecosystem IB questions review with key answers	Energy Flows video Energy Flow in Ecosystems-Bozeman Science How Ecosystems Work \| Biology \| Ecology Productivity Theory ( Guide 2016)

2.4 Biomes, zonation and succession

Significant ideas:

Climate determines the type of biome in a given area although individual ecosystems may vary due to many local abiotic and biotic factors.
Succession leads to climax communities that may vary due to random events and interactions over time. This leads to a pattern of alternative stable states for a given ecosystem.
Ecosystem stability, succession and biodiversity are intrinsically linked.

Resources:

2.5 Investigating ecosystems - Practical work

Significant ideas:

The description and investigation of ecosystems allows for comparisons to be made between different ecosystems and for them to be monitored, modelled and evaluated over time, measuring both natural change and human impacts.
Ecosystems can be better understood through the investigation and quantification of their components.

Resources:

Power points	Case Studies	Activities	Useful Links
Investigating ecosystems T 2.5 Applications and skills		Quadrat and Transect Lab What is the pH, and temperature of your soil? Is your soil fertile? Estimating the size of populations of small, mobile animals, using the Lincoln Index Create a dichotomous key from these Spiders Create a dichotomous key from these Beatles	Studying Ecosystems Sampling information Simpson's Diversity Index 2.5 Practical field work-video 2.5 Practical work part II -video