Introduction to Ecology

Introduction to Ecology

Ecology Ecology is…… The study of interactions between living (biotic) and non-living (abiotic) components in ecosystems.

Ecosystems • An ecosystem is a complex, self regulating system in which living things interact with each other and with non-living things. • Ecosystems come in all sizes and are made up of different biotic and abiotic factors.

Biotic or Abiotic? Abiotic Biotic • Sunlight • Frog • Grass • Wind • Temperature • Tree • Oil • Human Biotic Abiotic Abiotic Biotic Abiotic Biotic

Using the following diagram, list as many abiotic and biotic factors that you can!

Components of a Healthy Ecosystem • Contains native plant, animal, and insect species existing in balance with each other and non-living things. • Healthy ecosystems have: • An energy source • Definiteboundaries • Biodiversity • Nutrients, water, minerals, etc.

Biodiversity • Biodiversity – a variety of different organisms with different roles in an ecosystem. • To study the Earth’s biodiversity, similar species are placed into categories. • Create a properly labeled Bar Graph of the following.....

Table 1: Summary of the number of species in a wetland ecosystem

Name this axis too Name what is being described on this axis Figure 1: CREATIVE & DESCRIPTIVE TITLE HERE

How to describe an ecosystem • Sustainable: populations of plants, animals and other living organisms can continue to interact and reproduce indefinitely.

Biosphere II In the fall of 1991, there was a great deal of excitement surrounding a $200 million scientific experiment getting under way in Arizona. Eight people were sealed in a giant bubble called Biosphere II in the middle of the desert. It was meant to be a miniature version of Earth’s natural systems. The project was undertaken not only in anticipation of long flights in space, but also to demonstrate how well we understood the world around us.

Biosphere II contained a variety of ecosystems and plants and animals that were supposed to provide the same ‘ecosystem services’ that nature does; it would purify and produce water, recycle wastes, provide oxygen and absorb carbon dioxide, use photosynthesis to capture sunlight, and produce plants and food. The bubble covered several acres and housed a variety of ecosystems, including a desert, a miniature ocean, a grassland and a tropical forest. Nearly 4000 different plant and animal species were deliberately assembled to populate this airtight system.

Once the bionauts got inside, however, things started to go wrong pretty quickly. Oxygen levels plummeted, primarily because the mix of soil organisms was not correct and did not produce the proper proportion of gases. Oxygen concentration dropped to a level found above 17 000 feet of elevation. As a result, the bionauts suffered some of the alarming problems associated with low oxygen intake. Then nitrogen levels skyrocketed, creating a risk of brain damage. Most of the insects that had been carefully selected to pollinate the plants died off, dooming most of the bionauts’ intended sources of food and air and water purification. And many other species careered out of control – cockroaches, katydids, and a species aptly named crazy ants swarmed over everything. Some plants and vines also grew wildly. The bionauts spent increasing amounts of their time killing insects and hacking back vines. Eventually, the defeated pioneers, malnourished and sick, gave up and came out.

Despite its failures, Biosphere II taught us a great lesson – powerful evidence of how little we understand the ‘ecosystem services’ of replenishing air, water, and soil, and removing waste without our ever having to think of them. Efforts like Biosphere II shows some of the good sides of humanity: our curiosity, our determination. But at the same time it shows us that we’re like little kids. We’ve amassed this power, and we’ve deceived ourselves. We’ve been trained to look at big creatures as the most important, the most valuable, with ourselves as the biggest creature of all. We’ve ignored the relationships all large creatures must have with small ones, like ants, bacteria, and fungi, which provide the real fundamentals of survival.

We are still enormously ignorant of how complex and interconnected the world around us really is. As Biosphere II has reminded us, we have no ability to copy, let alone improve upon, the natural world. With extinction cutting out species left and right, we are tearing at the fabric of biodiversity on which we absolutely depend for our survival. http://www.youtube.com/watch?v=RmifaYcLPik

Parts of an Ecosystem • Species: group of organisms in an ecosystem that can reproduce with each other, and their offspring are viable • Population: groups of members of the same spp. that live in the same area • Community: populations of different spp. (biotic factors) that live and interact in an area • Niche: organisms role in an ecosystem

Ecosystems combine to make biomes! Biome: • large geographical area that contains similar ecosystems • categorized by plants, temperature and average rainfall • There are 5 terrestrial (land) biomes in Canada, and 2 aquatic (water) biomes. • Biomes combine to make the biosphere!

Biosphere  The part of the planet, including water, land and air, where life exists.

There are 3 main components that make up the physical environment of the biosphere: • Atmosphere • Lithosphere • Hydrosphere

The Atmosphere • Layers of gases that surround the Earth • Contains water, carbon dioxide, ozone • Helps keep the planet warm

The Lithosphere • Earth’s solid, outer layer • Includes the rigid crust and upper mantle • Runs 100km down from the surface • Includes soil

The Hydrosphere • All the water on Earth • ~97% of this water is salt water in the Earth’s oceans • All living things depend on water for survival

Can these spheres work on their own?

Introduction to Ecology