Today's Notes

 *Primary Productivity – How much organic matter can be supported by a given area

* Nutrient Limitation – the limited number of nutrients in soil such as phosphorus, nitrogen and potassium

*Algal Bloom – Nitrogen/Phosphorus wash into water sources from farming fertilizers. Algae go “crazy” and blooms rapidly. This blocks sunlight from other organisms and limits the amount of oxygen to the rest of the ecosystem 

Owl Pellet Lab (Sample)

Lab. Examining Owl Pellets

I.  Problem?

If all the moles in an area died out due to drought, would all the owls also die out?

Hypothesis – If all the moles in an area were to die out due to drought, the owls also die out.

Skills

-       I learned how to dissect an owl pellet.

-       I also learned how to identify the different bones of small vertebrates through a bone chart.

II Materials and Methods

-       Forceps

-       News paper

-       Bone chart

-       Water

-       Lab sheet

-       One owl pellet

III Procedure

1.     Receive the forceps from the teacher.

2.     Slightly dampen the owl pellet.

3.     Begin to dissect the pellet, separating fur and feather from bone.

4.     Using the bone chart, sort the bones and determine what organisms the owl ate.

5.     Answer the questions and draw conclusions.

IV Data and Observations

1.    Owl pellets are a dense mass of bone, fur and feather; materials that are indigestible to the owl.

2.    Many skeletons are incomplete

3.    The owl eats more of the smallest animals than the larger ones.

Owl Pellet Data Table

Type of Prey	#S  found in sample	Prey Biomass in grams	Total biomass consumed
Rodent	1	150g	150g
Shrew	2	4g	8g
Mole	1	55g	55g
Bird	2	15g	30g

Total Biomass Eaten -  243 g

V Analyze and Apply

1.     Forming owl pellets help owls survive better by allowing them to expel materials that are harmful for them to digest.

2.     Our particular owl ate six animals at least.

3.     You can tell the difference between a vertebrate and an invertebrate because in the case of vertebrates, backbones or vertebrae would be present.

4.     If an owl eats 120g of food in a day, it would need to eat 30 shrews.

5.     If all the shrews in a forest died out, the owl would only be slightly affected at first. Shrews are not the owl’s only prey; an owl could work around this hole in the food chain. However, overall, whatever the shrews eat will overpopulate and what eats the shrews will have a limited food source. Also, the owl’s other food sources will diminish as a single owl must eat more rodents, birds and moles to satisfy his need for energy. At the end of the “day”, this eradication of the shrews would lead to a trophic cascade because the food web is interconnected and if one thing dies, there are serious repercussions for everything else.

6.     If all the rodents in the forest died our after the shrews, again there would be a trophic cascade in the long run because one organism cannot be eradicated in an ecosystem without there being repercussions.

7.     If an owl were to eat 100 one-gram insects and one 100 gram rat, the insects would offer more energy. Because they are lower down on the pyramid of energy, they have a higher concentration of energy for the owl. In addition, the owl would use less energy to hunt insects as opposed to rate=s because they have slower reflexes and are more plentiful in the ecosystem. The owl does not also have to exert as much energy to hunt.

8.     Quality over quantity is more important to the owl. If he eats lower down the food chain, he can eat less, consume more energy, and exert less energy during the hunt. Eating secondary and tertiary consumers will decrease his energy, force him to eat more, hunt more and for longer.

9.     From this lab, I can conclude that an owl could not possibly survive the death of all moles in his ecosystem. This is so because food webs are so intertwined no organism could survive the eradication of another species without a trophic cascade occurring.

Chapter 4 Vocab due October 19

4.1 Climate

·      Weather – day to day conditions of the atmosphere, including precipitation and temperature

·      Climate – The average year to year conditions f temperature and precipitataion that occur in an area over a long period.

·      Microclimate – environmental conditions within a small area that differs signifigantly from that of the surrounding area

·      Greenhouse effect – process in which certain gases (carbon dioxide, methane and water vapor) trap sunlight energy in earth’s atmosphere as heat

4.2 Niches and Community Interactions

·      Tolerance – the ability of an organism to survive and reproduce under circumstances that differ from their optimal conditions s

·      Habitat – an area where an organism lives including the abiotic and biotic factors that affect it

·      Niche – a full range of physical and biological conditions in which an organism lives and the way the organisms use those conditions

·      Resource - any necessity of life such as food, water, nutrients, light and space

·      Competitive exclusion principle – principle that states that no two species can occupy the same niche in the same habitat at the same time

·      Predation – interaction in which one organism captures and feeds on the other organisms

·      Herbivory  - Interaction in which one animal, the herbivore feeds on producers

·      Keystone species – a single species that is not usually abundant in a community yet it exerts strong control over the structure of the community

·      Symbiosis – relationship in which two species live closely together

·      Mutualism – a symbiotic relationship in which both species benefit from the relationship

·      Parasitism – symbiotic relationship in which one organism lives on or inside the other organism and harms it

·      Commensalism – the symbiotic relationship between organisms in which one organism benefits and the other is neither helped nor harmed

4.3 Succession

·      Ecological succession – series of gradual changes that occur in a community following a disturbance

·      Pioneer species – the first species to populate an area after a succession

·      Primary succession – succession that occurs in an area in which no trace of a previous community is present

·      Secondary succession – type of succession that occurs in an area that was only partially destroyed by disturbances

4.4 Biomes

·      Canopy – Dense covering formed by the leafy tops of tall rain forest trees

·      Understory – layer of a rain forest found underneath the canopy formed by shorter trees and vines

·      Deciduous – Term used to refer to a type of tree that sheds its leaves during a particular season each year

·      Taiga – a biome with long cold winters, and a few months od warm weather, dominated by coniferous evergreens also called a boreal forest

·      Humus  - material formed by decaying leaves and other organic matter

·      Coniferous – Term used to refer to the trees that produce seed bearing cones and have thin needle shaped leaves

·      Permafrost – layer of permanently frozen subsoil found in the tundra

4.5 Aquatic Ecosystems

·      Photic zone – sunlight region near the surface of the water

·      Aphotic zone – Dark layer of the oceans below the photic zone were sunlight does not penetrate

·      Benthos – Organisms that live attached to or near the bottoms of bodies of water

·      Plankton – microscopic organisms that live in aquatic environments

·      Wetland – ecosystem in which water either covers the soil or is present at or near the surface for at least part of the year

·      Estuary – a kind of wetland formed where a river meets the ocean

Cycles of Matter Study Guide for Ecology Quiz (10.17.11)

This link is for an "interactive" activity that makes a lot more sense than what we did in class for the Nitrogen Cycle.

http://www.classzone.com/books/ml_science_share/vis_sim/em05_pg20_nitrogen/em05_pg20_nitrogen.swf