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This case study is designed to help students learn about the ecosystem services of Earth (Biosphere 1) by examining the challenges faced by the designers who tried to replicate its components in Biosphere 2. In 1991, four men and four women entered Biosphere 2, a man-made closed ecological system in Arizona, to see if eight biospherians could be sustained by this miniature version of Biosphere 1. The project succeeded in producing most of the food needed, but required additional oxygen before the end of the two-year experiment. After an introduction to Biosphere 2, students learn about the four main types of ecosystem services and discuss how Biosphere 2 might provide these services. At the end of the case, students calculate their own ecological footprint, demonstrating how humans are overreaching the ecosystem services of Biosphere 1, just as the biospherians could not be sustained by the ecosystem services included in Biosphere 2. The case is suitable for an introductory undergraduate course in biology, ecology, or environmental science.

This interrupted case study, designed for an introductory biology or environmental science course, introduces students to the complexity of ecosystems by examining changes in trophic interactions and abiotic factors in a freshwater ecosystem as a result of human actions. The case narrative describes the recent and undesirable appearance of decomposing algae (Cladophora glomerata) on a public beach in the Laurentian Great Lakes. Students are asked to use the scientific method by creating hypotheses and examining observational data to describe biotic and abiotic components of the Great Lakes ecosystem. The case requires students to differentiate between benthic and pelagic environments (e.g., the influence of depth and phytoplankton density on light availability, and the availability of phosphorus) and the interactions between organisms in both environments. Students also examine shifts in these interactions as a result of the newly introduced zebra and quagga mussels, which have ultimately resulted in the algae's presence on the beach. There are also opportunities to discuss the impact of these ecosystem changes on people who own property and/or visit the beach.

Mathematician-turned biologist Dr. Corina Tarnita describes the importance of termite mounds in a savanna ecosystem. Termite mounds are biological hotspots that concentrate nutrients and water in semi-arid savanna ecosystems. When viewed from above, the mounds form a strikingly regular polka-dot pattern. Dr. Corina Tarnita uses mathematical modeling to explain the regularity of the pattern, how it arises, and how the mounds enhance the stability of the ecosystem.

As you learned in Unit 4, ecosystems are a complex and delicate balancing game. The addition or removal of one species affects many other species with which it might compete for, or provide food. In this lab you will get a chance to "build your own" ecosystem, and explore the effects of these interrelationships.

Fact sheets explain ecological issues, define terms and concepts, and provide references for additional information.

The short film opens with two questions: "So what determines how many species live in a given place? Or how many individuals of the species can live somewhere?" The research that provided answers to these questions was set in motion by key experiments by ecologists Robert Paine and James Estes. Robert Paine's starfish exclusion experiments on the coast of Washington state showed that removing starfish from this marine ecosystem has a big impact on the population sizes of other species, establishing the starfish as a keystone species. James Estes and colleague John Palmisano discovered that the kelp forest ecosystems of the North Pacific are regulated by the presence or absence of sea otters, which feed on sea urchins that consume kelp. These direct and indirect effects of sea otters on other species describe a trophic cascade. These early studies were the inspiration for hundreds of investigations on other keystone species and trophic cascades, as well as ongoing studies into the regulation of population sizes and species numbers.

Our planet's diverse, thriving ecosystems may seem like permanent fixtures, but they're actually vulnerable to collapse. Jungles can become deserts, and reefs can become lifeless rocks. What makes one ecosystem strong and another weak in the face of change? Kim Preshoff details why the answer, to a large extent, is biodiversity.

This case study examines a variety of biological factors that may have been involved in the 2013 dolphin "unusual mortality event" (UME) on the East Coast of the United States. The story follows a news reporter and four different scientists who are preparing their notes for speaking at a public hearing about the dolphin die-off event. After reading the story, students assume the roles of these scientists and use the jigsaw method to gather, analyze, and share information.  Due to the interdisciplinary nature of environmental toxicology, this case study exposes students to four main topics: ecology of ecosystems, endocrine system/chemical messaging, immune system function, and virus biology.

As benign as it may look up close, the tiny seaweed Caulerpa taxifolia can wreak quite a bit of havoc on coastal ecosystems. This super algae is very adaptable; it also grows fast and spreads easily. Eric Noel Muñoz gives the details of this plant's incredible invasion, shedding light on the risks of introducing invasive species into new ecosystems.

5:27 video, Our planet was once populated by megafauna, big top-of-the-food-chain predators that played their part in balancing our ecosystems. When those megafauna disappear, the result is a "trophic cascade," where every part of the ecosystem reacts to the loss. How can we stay in balance? George Monbiot suggests rewilding: putting wolves, lions and other predators back on top -- with surprising results.

The first activity will have you investigate some of the animals in the Mexican ecosystem.  Figure out who are the predators and who are their prey and build your own food web.

Are we witnessing a sixth mass extinction? What factors threaten ecosystems on land and in the sea? What are researchers doing to try to conserve biodiversity and ecosystems such as tigers in Asia and coral reefs around the world? What tools do we have to avoid a global catastrophe? In six half-hour lectures, three leading scientists describe the state of biodiversity on our planet and how to face the great challenges that lie ahead.

It is now well known that non-native species have the potential to be harmful to an ecosystem, but that wasn't always the case, and getting rid of non-native invasive species is usually a difficult task. This brief, interrupted case study tells the story of kudzu's introduction into the United States in the late 1800s. It also examines (and even questions) how we define words like "native" versus "non-native" and "invasive" versus "non-invasive." Students will learn how invasive species impact ecosystems and why some non-native species never become established. They also will address questions related to eradicating non-native invasive species. For example, is it okay to attempt to get rid of a non-native species with another non-native species? As part of the activity, students also will have to decide whether or not kudzu should be considered "native" since it has been in the United States since 1876. Originally designed for a general biology course for majors, the case has also been used in a biology class for non-majors as well as an environmental biology class.

Data rich simulation where students adjust parameters and run simulator for 100 iterations and see how 1) two plant species compete for a niche or 2) how composition of a food web changes over time Links to online textbook, videos, visuals, scientists.

Simulators which display cummulative generation graphs for variables.  Very cool data rich resource!  Includes Carbon cycle, demographis (human populations), Disease transmission, ecology, and energy simulations.

In this case study students are provided with information for piecing together the story of how forest fragmentation and biodiversity loss can affect the risk of Lyme disease transmission to humans. The case introduces the dilution effect, a widely accepted theory-and one of the most important ideas in disease ecology-which suggests that disease risk for humans decreases as the diversity of species in an area increases. It also explains how landscape fragmentation, one of the most common threats to biodiversity, can influence the risk of Lyme disease for humans. Students interpret and discuss various figures to develop a concept map that connects all the individual results of the story. Students gain an appreciation for the complexity of species interactions in an ecosystem, the effects of forest fragmentation on these interactions and the possible consequences for human health. This activity was developed for an undergraduate introduction to environmental sciences course under the topic of biodiversity and conservation, but would also be suitable for interdisciplinary studies interested in examining the connections between conservation and public health.

Hank gives the run down on the top five ways humans are negatively impacting the environment and having detrimental effects on the valuable ecosystem services which a healthy biosphere provides.

Predators don't control populations of their prey just by killing them. They also paint what is termed a landscape of fear, inhibiting prey from feeding and turning parts of their habitat into no-go zones. Now it appears that this has far-reaching effects throughout the food web.

mpacts and adaptations of climate change across the major regions of the US. Also broken down across 10 sectors-agriculture, coasts, ecosystems, energy, human ,health, etc. 

2:25 video  Scientists have recently discovered that the limbs of some sea stars have been turning into goo, and populations are dying off! Why is this happening, and will this hurt their ecosystem? Join Laci as discusses how this disease is spreading, and why it have some negative consequences.