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Honors Marine Biology. January 6, 2015 Marine Ecology: Module 8. Happy New Year !. Class Challenge 4-H Fair Forms are due January 11 in the fair office. 4-H Opportunities. Quiz: Identify Dolphin Anatomy. Ocean Ecosystems in Review.
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Honors Marine Biology January 6, 2015 Marine Ecology: Module 8
Happy New Year ! • Class Challenge • 4-H Fair Forms are due January 11 in the fair office. 4-H Opportunities
Ocean Ecosystems in Review Abiotic: The components of an environment, such as temperature, pressure, and salinity, provide the conditions under which an organism must survive in order to live there.
Biotic: components of an environment whereby organisms must interact with other organisms. They compete for living space and food, attract mates, and interrelate in many other ways. Basically, the living part of an environment
So….. The character of any environment, then, is determined by both biotic and abiotic factors.
An Ecosystem An Ecosystem is composed of one or more communities, including the physical environment of a specific area. This means everything! Including living and nonliving in a given location. See page 187- 188 A River Delta
Sarasota, Florida Let’s consider different ecosystems where we live. Myakka State Park Big Pass Charlotte Harbor Any more…?
Carrying Capacity Both biotic and abiotic factors play a part in controlling the size of a population. Environments can only support a certain quantity of individuals before conditions begin to become detrimental.
Each organism needs specific resources in order to live. • Nutrients, light and space.
Limiting Resources When there is a small supply of a needed factor ( Nutrients, light and space) for a population to grow, that factor is called the limiting resource of the population.
Self-Regulating Population Population many times prevents itself from excessive growth by using up available resources. This limits the growth rate by the size of the population. This can only happen if the population gets too large.
Food Webs of Marine Life • Feeding relationships are often shown as simple food chains – in reality, these relationships are much more complex, and the term ‘food web’ more accurately shows the links between producers, consumers and decomposers.
A food web diagram illustrates ‘what eats what’ in a particular habitat. • Pictures represent the organisms that make up the food web, and their feeding relationships are typically shown with arrows. • The arrows represent the transfer of energy and always point from the organism being eaten to the one that is doing the eating.
Trophic Levels • Organisms in food webs are commonly divided into trophic levels. • These levels can be illustrated in a trophic pyramid where organisms are grouped by the role they play in the food web.
How can scientists determine if we have a healthy “food web” ? • We monitor bay scallops in southwest Florida because they are an important species to both humans and the environment. • When coastal waters are able to support bay scallops it is a sign of reasonably good water quality and seagrass conditions. • Many volunteers participating in the search this year commented about how healthy the seagrass looked. Healthy seagrass is very important habitat for bay scallops, but it’s only part of the story.
2012 BAY SCALLOP SUMMARY: FOR THE CHARLOTTE HARBOR ESTUARIES OF LEMON BAY & GASPARILLA SOUND Volunteers gather scallop data to determine health of our area waters.
Reef Balls- Why Build Them • Man’s activities and natural disasters have led to a reductions in our natural reef systems. • Recreationally, growth in sports fishing, scuba diving, and boating has increased the pressures on these systems. • Commercially, our seafood industry is dependent on developing the ocean to enable ever larger, yet sustainable, harvests.
The loss of our natural systems, coupled with increased use, compels us to do everything we can to save natural reefs. Even so, the natural reefs cannot rebuild themselves fast enough to meet human demands. Long lasting artificial reefs are useful tools for restoring our reef systems to a natural and productive balance
The Carbon Cycle is a simple cycle in the ecosystem. Is a simple cycle in an ecosystem. Carbon dioxide (CO2) is an atmospheric Gas and is also found in dissolved water. This is the main source of carbon in living systems. During photosynthesis, primary producers fix carbon dioxide and produce simple sugars. These sugars are the main source of carbon for all other organisms in the ecosystem. Respiration of that sugar by consumers and decomposers converts the organic carbon compound back into inorganic carbon dioxide, which is then available for producers again.
Figure 8.10 • Beginning with primary producers, they take the dissolved carbon dioxide (inorganic) from the water and use sunlight to convert it and water into sugar (an organic molecule that contains the previously inorganic carbon) and oxygen. • This is the carbon fixation process. • The carbon that is in the organic molecule is then eaten by a herbivore that is in turn eaten by a carnivore.
The carbon is the inorganic (CO2) that gets distributed to all the living creatures. • At the same time, primary producers, herbivores and carnivores are all burning their food for energy, so they are all burning their food. • When the organisms die, their bodies become detritus, and the decomposers convert the carbon into carbon dioxide so that the primary producers use it and the cycle begins again.
The Nitrogen Cycle • In living organisms, nitrogen is not present in as large a quantity as carbon, but nitrogen compounds such as DNA and amino acid are essential for life. • The nitrogen cycle is essential for making sure that there is enough nitrogen in an ecosystem so that these compounds can be made.
The nitrogen cycle begins the same way as the carbon cycle, with gaseous nitrogen (N2) from the atmosphere dissolving into the water. • This is where the two cycles differ dramatically.
Most organisms are unable to utilize nitrogen in its gaseous natural form. • Some types of bacteria (like blue-green algae) can convert the nitrogen into other forms (like nitrates), that most marine organisms can use. • Converting nitrogen into useful forms is called nitrogen fixation. Without it, organisms could not survive.
Once nitrogen has been converted into a useable form, it enters the next part of the nitrogen cycle. • The most important form of fixed nitrogen is nitrate. • Primary producers use nitrate and other nitrogen compounds in their synthesis of biologically important molecules.
As the primary producers are eaten by the herbivores, and as the herbivores are eaten by the carnivores, nitrogen passes to all organisms in the ecosystem. • Nitrogen gets back into the system through waste and decomposers.
Zones of the Marine Environment The Marine Environment can be divided into two major groups: (Figure 8.12) Benthic: Describing organisms that live on the ocean bottom. Pelagic: Describing organisms that live in the cater column away from the ocean floor.
The Blue Planet The Open Ocean http://youtu.be/0LeicqYo5Hc
Lab: Mud Flat Ecosystem Lab: Plant and animal identification of Mudflat Ecosystems 1. Observe, identify and classify and draw samples collected from a mudflat A. Macroscopic observation B. Microscopic observation CrustaceansMolluskAlgae(Red,green, brown) Ascidian(seabread) 1. Porceline Crab Sand collar Irish Moss (Red) sea squirt 2. Spider Crab Moon Snail Codium (green) sea bread 3.Horshoe Crab Cohog Sea lettuce (green) 4. Mud Crab FL fighting Conch 5. Hermit banded tulip Drawings of each:
Homework • Read Module 9: pages 211-226. • Answer OYO Questions: 9.1 – 9.12 • Study Guide Questions: define: a-d and questions 2 – 18. • Complete lab: Mud Flat Ecosystem • Class Challenge: