1. Things that Shape Ecosystems

2. Biotic Factors
Biotic factors refer to living factors (organisms) that shape ecosystems.
All living members of an ecosystem are the biotic factors, from the smallest to the largest.
We study how these organisms effect one another as well as how they effect their nonliving surroundings.

3. Abiotic Factors
Abiotic factors are the nonliving components of an ecosystem.
Examples of this may be precipitation, humidity, temperature, wind, bodies of water, the rocks and abiotic component of the soil, the time of the season, etc.
These factors have effect, whether direct or indirect on the biotic components of the ecosystem.
The biotic can have effect on the abiotic. A prime example of this is the roll of moss in rock weathering.

6. Habitat and Niche
The habitat of an organism describes where it lives (its address).
The niche of an organism describes how the organism interacts with its ecosystem (its occupation). It describes the full range of physical and biological conditions in which an organism lives and how it uses those conditions.
An organism’s place in the food web, how and where it reproduces and how it may alter the abiotic facors would describe part of its niche.
Biotic and abiotic factors determine the type of niches that would be available to organisms.

10. Community Interactions: Competetion
Organisms attempt to use the same resources in an ecosystem. Resources are such this as light, water, nutrients, food, space etc. In other words, any necessity of life.
Due to competitive exclusion principle, the “loosing” population will either die out or adapt to a new niche (if that is within its genetic capabilities).

11. Community Interactions: Predation
This is an interaction where one organism captures and feeds on another organism.
The organism that does the catching/killing/eating is the predator.
The organism that gets caught/killed/eaten is the prey.
There are many means by which predators capture and kill (and eat) their prey. Examples:
-Spider:
-Lion
-Alligator Snapping Turtle

13. Symbiosis
Mutualism
Commensalism

14. Symbiosis
Parasistism
Amensalism

30. Succession
Predictable changes that take place in a community over time.
An ecological disturbance (these occur artificially and naturally) may occur to trigger succession.
Primary Succession: No soil present at the start. The soil must be formed. This occurs due to both biotic and abiotic factors.
The abiotic factors include such things as wind, rain, freezing and thawing.
Biotic factors are due to pioneer species such as lichens due to the chemicals that they secrete and their decomposition.

31. ….succession
Examples of disturbances that may result in primary succession would be volcanic activity, what is left behind after glacial melting and a nuclear blast area. -Secondary Succession occurs when the disturbance doesn’t remove the soil. -Examples of disturbances that may result in secondary succession would be forest fires, the abandoning of farm land where trees had been cut down, or clear cut logging operations. -When succession is “complete,” a CLIMAX COMMUNITY results, this is the condition that usually characterizes a particular BIOME.

32. ….Succession
Climax communities are still undergoing changes. This can result from climate fluctuations, invasive species, etc.
Ecosystems are never completely unchanging.
Fire is necessary for some species to reproduce, such as the jack pine. The Jack pine is necessary for the survival of some species (such as the Kirkland's Warbler, right here in Michigan).

35. Secondary Succession

38. Secondary Succession Beginning

39. Whale fall Succession

40. Soil Triangle