Part 1 Ecosystems Everything Is Connected Chapter 7

Part 1: Ecosystems: Everything Is Connected Chapter 7: Aquatic Ecosystems. Environmental Science and the Earth

Ecosystems: Everything Is Connected • Example of the idea that “everything is connected” • In 1995, scientists interested in controlling gypsy moths, which kill oak trees, performed an experiment. Photo by R. Jowsey

Everything Is Connected: Example http: //news. nationalgeographic. com/news/bigphotos/image s/071022 -vibrating-mice_big. jpg • The scientists removed most mice, which eat young gypsy moths, from selected plots of oak forest. • The number of young gypsy moth eggs and young increased dramatically.

Everything Is Connected: Example • The scientists then added acorns to the plots. • Mice eat acorns, therefore the number of mice soon increased, and… • The number of gypsy moths declined as the mice ate them as well. http: //cakboliv. files. wordpress. com/2009/08/a corns_nut_mc_. jpg

Everything Is Connected: Example • This result showed that large acorn crops can suppress gypsy moth outbreaks. http: //images. suite 101. com/608399_com_img_9740. jpg

Everything Is Connected: Example Photo by R. Jowsey • Oh but there is more!!! • Interestingly, the acorns also attracted deer, which carried ticks. • Young ticks soon infested the mice. http: //www. deerticks. com/content/modules/rhino. pages/files/uploads/deerticks/img-002. jpg

Everything Is Connected: Example • Wild mice carry the organism that causes Lyme disease. • Ticks can pick up the organism when they bite mice. • Then the ticks can bite and infect humans. http: //ladydamorea. files. wordpress. com/2012/06/deertickbullseye. jpg

Everything Is Connected: Example • This example shows that in nature, things that we would never think were connected— mice, acorns, ticks, and humans—can be linked to each other in a complex web http: //www. thefastertimes. com/globalpandemics/files/2010/01/borrelia-burgdoferi -life-cycle. gif

Defining an Ecosystem • The mice, deer, moths, oak trees, and ticks in the previous example are all part of the same ecosystem. • An ecosystem is all of the organisms (biotic) living in an area together with their physical (abiotic) environment.

Defining an Ecosystem • Ecosystems can be large like an oak forest or coral reef, or they can be small like the vacant lot next door to your home. http: //www. biology-blog. com/images/blogs/122006/oak-forest-5720. jpg • The Natick projects. http: //www. nexuslearning. net/books/Holt_Env_Science/4 -1. pdf

Defining an Ecosystem • Just like living things are connected, so to are ecosystems. • Things move from one ecosystem into another. • Soil washes from a mountain into a lake, birds migrate from Michigan to Mexico, and pollen blows from a forest into a field.

The Components of an Ecosystem • In order to survive, ecosystems need at least five basic components: 1. A source of energy 2. Mineral nutrients 3. Water 4. Oxygen 5. Living organisms Photo by R. Jowsey

Biotic and Abiotic Factors • An ecosystem is made up of both living and nonliving things. • Biotic factors are the living and once living parts of an ecosystem, including all of the plants and animals. • The biotic parts of an ecosystem interact with each other in various ways (food webs, symbiosis, etc).

Biotic and Abiotic Factors • While living things interact with each other in an ecosystem, they also interact with the nonliving factors in an ecosystem. • The non-living components of an ecosystem are known as abiotic factors.

Biotic and Abiotic Factors • Identify three biotic and three abiotic factors that are in the cold northern ecosystem of Denali National Park in Alaska (shown in photo). http: //www. nexuslearning. net/books/Holt_Env_Science/4 -1. pdf

Biotic Factors 1. 2. 3.

Abiotic Factors 1. 2. 3.

Organisms • An organism is an individual living thing. • You are an organism, as is an ant crawling across the floor, an ivy plant on the windowsill, and a bacterium in your intestines. • Organisms are classified into 4 major groups: Bacteria, Plants, Protists, and Animals. Period 1 Organism Peter Creed

Species • A species is a group of organisms that are closely related. • In order for two organisms to be classified into the same species, they must meet thesefour criteria. • The two organisms must able to: • • Successfully mate in a Natural Environment (not a lab or zoo, etc. ) and produce viable offspring (healthy, able to survive to adulthood) and those offspring are fertile (can reproduce). • All humans, for example, are members of the species group sapiens and the genus group Homo. This produces the scientific name for humans; Homo sapien.

Species http: //i. cdn. turner. com/cnn/2010/US/09/23/what. is. zedonk/story. ze donk. carr. jpg • The photo shows a zedonk. • A zedonk is a cross between a zebra and a donkey. • The zedonk is a sterile animal and cannot reproduce. Therefore, a zebra and a donkey are NOT the same species.

Species • Zebras and donkeys can successfully mate, in a natural environment and produce viable offspring. • Are zebras and donkeys therefore members of the same species? Why or why not? http: //www. greatplay. net/i mages/zebra. jpg http: //upload. wikimedia. org/ wikipedia/commons/thumb/7 /7 b/Donkey_1_arp_750 px. jpg /250 px. Donkey_1_arp_750 px. jpg http: //i. cdn. turner. com/cnn/2010/US/09/2 3/what. is. zedonk/story. zedonk. carr. jpg

Populations • A population is all the members of the same species that live in the same place at the same time. • An important characteristic of a population is that its members usually breed with one another rather than with members of other populations. • Populations have really cool names: pod of bottlenose dolphins, gaggle of Canadian geese, murder of crows, smath of jellyfish. • http: //en. wikipedia. org/wiki/List_of_animal_names

Populations http: //www. nexuslearning. net/books/Holt_Env_Science/4 -1. pdf • The Bison will usually mate with another member of the same herd, just as the wildflowers will usually be pollinated by other flowers in the same field.

Communities • An organism does not live alone and neither does a population. • A community is a group of various species that live in the same place and interact with each other.

Communities Photo by R. Jowsey • A pond community, for example, includes all of the populations of plants, fish, and insects that live in and around the pond. • All of the living things in an ecosystem are members of the same community.

Communities • The most obvious difference between communities is the types of species they have. • Land communities are often dominated by a few species of plants. In turn, these plants determine what other organisms live in that community.

Communities • For example, the most obvious feature of a Colorado forest might be its ponderosa pine trees. • This pine community will have animals, such as squirrels, that live in and feed on these trees. http: //www. sprucepointtreefarm. com/images /spruce. jpg http: //shelledy. mesa. k 12. co. us/staff/comp uterlab/images/CO_Mammals_Pine_squirr el. jpg

Habitat • The squirrel discussed above lives in a pine forest. The pine forest is the squirrel’s habitat. • A habitat is where an organism lives. • The habitat of the salamander in this photo is a damp forest floor. http: //www. nexuslearning. net/books/Holt_Env_Scien ce/4 -1. pdf

Habitat http: //www. coralreefinfo. com/images/coral_reef. jpg • Every habitat has specific characteristics that the organisms that live there need to survive. • A coral reef contains sea water, coral, sunlight, and a wide variety of other organisms. • If any of these factors change, then the habitat changes because everything is connected.

Niche • An organism’s niche is the role it plays in an ecosystem. • Often describes where an organism “fits” in a food chain. • Example: A woodpecker’s niche is eating insects