Intro to Ecology Final

Limnetic zone

Limnetic zone

________- where sunlight does not penetrate to the bottom (horizontal)

Epilimnion

________: warmest, highest dissolved oxygen.

Hypolimnion

________: coldest, lowest dissolved oxygen (due to high biological oxygen demand (BOD) by decomposers)

Lignin

________: fills in spaces in cell wall.

Ecosystems

________ depend on the recycling of chemical elements.

Ammonium nitrate

NH4NO3 granules applied to soils (explosive)

Littoral zone

from shore out toward center, as far out as sunlight penetrates to the bottom

Euphotic zone

where there is sunlight

Aphotic zone

where there is no sunlight

Metalimnion

rapid temperature change

Hypolimnion

coldest, lowest dissolved oxygen (due to high biological oxygen demand (BOD) by decomposers)

Mississippi River

10th order

Amazon River

12th order

Straight

stream order 1-3, small headwater streams

Meandering

stream order 4-6, mid-reach streams

Braided

stream order 7-12, large, low-gradient rivers

Nitrogen fixation converts atmospheric nitrogen gas (N2):

to ammonia or ammonium (NH3 or NH4)

Nitrogen Fixation done by?

Some bacteria and by lightning converting ammonia in turn, Ammonia can then also be converted to nitrite (NO2-), and nitrate (NO3-) which plants can use

Phosphorus Cycle

· No atmospheric pool

· Most in mineral deposits and marine sediments

o Much of this in forms not directly available to plants

· Slowly released in terrestrial and aquatic ecosystems via weathering of rocks

· Usable form: dissolved inorganic phosphate

Effects of Human Activities on Phosphorus Cycles

· Remove large amounts of phosphate from the earth to make fertilizer

· Reduce phosphorus in tropical soils by clearing forests

· Add excess phosphates to aquatic systems from runoff

Only ______ nitrogen (ammonia; NH3) is usable by plant

Fixed

Decomposition takes place in steps

1. Scavangers (ants, flies, vultures, hyenas)

2. Bacteria, fungi

Lentic waters are fromed by?

Glacial, river, tectonic, and volcanic activity

Changes that occur longitudinally

• Increase in size (width and depth)

• Increase in volume (as tributaries flow in)

• From steep gradient to low gradient (flatter land)

Floodplain:

flat land adjacent to a stream or river that experiences occasional or periodic flooding

Flood magnitude:

• defined in terms of return period, or recurrence interval

  • E.g 100yr flood

• Just an average, based on historic data

• Can have back-to-back 500yr floods

Arsenic

________ is toxic and is a carcinogen.

Ogallala Aquifer

The ________ is the worlds largest aquifer.

Intertidal (littoral) zone

between high and low tide; 2x/d

Neritic zone

between low tide and edege of continental shelf

• E.g. Kelp forests

• E.g. Eelgrass beds

• E.g. Coral reefs

Oceanic zone

beyond continental shelf (open ocean)

• E.g. Epipelagic plankton communities

• E.g. Hydrothermal vents

• E.g. Deepwater coral communities

Epipelagic

Surface to 200m

Bathypelagic

1000-4000m

Abyssopelagic

4000-6000m

Hadopelagic

6000m

Pelagic

open water

Benthic

Bottom

Point source of contaminants

can be trace it back to the end of a pipe, e.g., WWTP, Factories, power plants

Non-point sources

cant trace it back to a single pipe

Emerging contaminants of concern

Less visible, Subleathal effects such as an endocrine system disruption

Weather

refers to a local areas short trem physical conditions scuh as temaptrues arnd percipatiaon

Climate

refers to a regions average temperatures and percipaitaion over time

Five Major Ocean Basins

Atlantic, Pacific, Indian, Arctic, Southern (Antarctic)

Groundwater

Some precipitation infiltrates the ground and is stored in soil and rock

Surface water

Water that does not infiltrate or evaporate runs off into bodies of water

Biggest uses of water in U.S?

• Irrigation (70%)

• Industries (20%)

• Drinking (cities and residences) (10%)

• In general, ~70% of water we withdraw from rivers, lakes, and aquifers is not returned to these sources.

What is a contaminant?

Any substance that is present where it does not belong, or is present at levels that might cause harmful effects to humans or the environment

Clean Water Act, 1972

Control of point sources

PCB is a?

Legacy contaminant (once used and banned but continues to linger in the environment)

Emerging contaminants of concern:

Less visible, Subleathal effects such as an endocrine system disruption

Industrial point source example

Factory discharging wastewater from a pipe into a body of water

Municipal point source example

City owned waste water treatment plant discharging wastewater into a body of water

Agricultural non point source example

Fields of crops that have run off of pesticides into a body of water

Urban non point source example

Contaminants running into storm drains in city areas into a body of water

Conclaves paper results

• Breakdown rate: fastes for E. vernia (native)

  • Also fast for Eucalyptus

  • Slowest for protuim (cerrado)

    • Larger cuticle

    • Tannins

• Coloinization by fungi

  • Highest for E.Vera and Protium

  • Lowest for Eucaluptus

• Colonilatization of invertebrates

  • No different in density, richness, or biomass

  • Increased w/ ergosterol (fungi)

Definition of a Biome

A large terrestrial region of Earth, the type of which is determined by the climate, and predominate vegetation type (grasses, shrubs, or trees)

Key factors on determining climates

• Latitude (distance from equator)

• Elevation

• Mountains and oceans

• Ocean currents

• Global air circulation (winds)

Latitude on climate

Because of its curvature, Earth receives an uneven distribution if solar energy

Wind on determining climate

Keeps tropics from being unbearably hot.

Prevents rest of world from freezing

Tropical Rain Forest

General location: near the equator, in moist areas

Climate: warm temp., high humidity, heavy rainfall (100’’ or more/yr), temp 68-93F

Dominate vegetation

• Large trees

• Not dominated by a single tree species

• Often covered with vines, figs, and epiphytes

• Trees sometimes collapse under the weight of all life they support

Five layers: Emergent, upper canopy, understory, shrub, and forest floor layers

Filling diverse niches enables species to avoid or minimize competition and coexist

Fire: not important for survival of the biome

Plants and Animals: very high in species diversity and plants

Soils: very poor, acidic, low organic matter, most nutrients tied up in trees, shollow roots,butress trunks

Human Impacts: Removal of rain forest vegetation for agriculture and wood industry, huge loss of biodiversity

Sumatran Organgutan

• Found only in tropical rainforests on island of Sumatra. Very few left. Burning forests to set up palm oil plantation

Some countries do ecotourism and farm sustainable materials in the rain forests

Tropical Savanna

General location: Near equator, in dry areas

Climate: Very warm temp year-round, Precipitation comes during rainy season (summer) 15-20 inches with monsoon (vs 4’’ in winter)

Dominate Vegetation: Grasses (C4 grasses) with sattered drought resistant trees (e.g., baobab and acaci), Trees shed leaves during dry season

Animals: Grazing animals concentrate at watering holes, herbivores: Zebras, gazelles, giraffes, predators: lions and hyenas

Fires: Seasonal fires are important to biodiversity

Soils: Generally poor, low nutrient, low fertility, dry, porous (drains rapidly)

Human impacts: overhunting (including trophy hunting), overgrazing, fires (putting them out or starting), conversion to farm land

Desert

General location: Tropical, Temperate, and Polar regions

Definition: Deserts are areas where evaporation exceeds precipitaion

Climate: Very little precipitation (<10’’/year). Arid. Temperature may vary greatly, even between day and night

Dominate Vegetation: Cacti, with some grasses and shrubs, adaptations allow them to stay cool, get h2O. Some have little or no vegetation

Soils: Very poor soils, Low organic matter content. So hold little water/nutrients. May be salty which inhibits plant growth

Animals and Plants

• Active at night (e.g., Kangaroo rats, Rattlesnakes)

• Able to travel long distances for water

• Thick, leathery leaves to reduce water loss; green trunks instead of leaves; spines to keep from being eaten; CAM

Scorpion: Nocturnal, burrow by day, hard cuticle layer reduces water loss, 8-12 eyes, but see very little, see with their feet (pressure sensing organs)

Human Impacts: Suburban sprawl, invasive species, orvergrazing, altercation of flow (CO River), mining (copper mining)

Seeing more desertification with climate change (expansion of preexisting desert)

Chaparral (Mediterranean)

General location: Coastlines where cool water meets warm land mass, SoCal

Climate: Mild (Mediterranean) Long, Warm, Dry summers, 10-40’’ of percipitaion

Dominate vegetation: Shrubs. THickets of spiny, evergreen shrubs. Other common plants include yucca, poison oak, scrub oak, cacti, manzanita

Animals: Common animals include Coyotes, mule deer, lizards, foxes, jack rabbits

Soils: generally shallow, over fractured bedrock, low fertility,

Fire: Fire is a normal component in this biome (germinating plants seeds), but has been suppressed, leading to bigger fires.

Human Impacts: Encroachment, fire suppression, invasive species, grazing, agriculture

Temperate Grassland (prarie)

General location: temperate areas that are dry, but not too dry

Climate: Extreme temperature differences (-30 to 80), 20-35’’ of rain/year. Too moist for dessert, too dry for forests

Dominate Vegetation: Grasses. Also flowers, herbs, some scattered trees (e.g., oak), Limited precipitation, drought, and fire support grasses better than trees, two types of grasses; tallgrass (humid, wet), shortgrass (dry)

Soils: Tallgrass is very fertile; organic matter accumulates (“bread basket”), shortgrass is thinner, drier soils

Animals and Plants: Prairie dog, Milkweed, Badger, Purple coneflower, Big bluestem grass, Bald eagle

Fire: Fire is an important part of theperate grassland ecology. Fire germinates the seeds. Keeps forests from growing. Part of prairie restoration projects

Human impacts: Overgrazing, soil erosion/loss, pesticide contamination, Fires, Overhunting (e.g., buffalo), Native grasses replaced with monoculture/agriculture

Temperate Deciduous Forests

General location: Temperate (losses their leaves) areas that are moist

Climate: Distinct seasons, Precipitation falls all year (30-60’’/yr), Extreme temp differences (-30 to 90)

Dominate Vegetation: Trees. Lots of “understory” (herbs, shrubs), Trees survive winter by dropping leaves and becoming dormant. May have one or more dominant species (e.g, “oak-hickory forest”, “red maple forest”)

Soils: Leaf fall produces nutrient-rich soil. Holds a lot of moisture

Fire: not important

Animals: White-tailed deer, squirrels, rabbits, opossums, raccoons, warblers, robins, etc.

Human Impacts: logging, Urban sprawl, Agriculture, Acid rain

Coniferous Forest (Boreal forest, taiga)

General Location: Cooler, drier areas. Higher latitudes, altitudes

Climate: Long, cold winters; short, cold summers. Temp range -40 to 70. 10 to 35’’ rain/year

Fire: not important

Dominate Vegetation: Trees, Evergreens (coniferous trees). Often have only a couple dominate species (e.g., “spruce-fir forest”)

Soils: Soils are nutrient-poor somewhat acidic. Slower decomposition rate

Bogs (like a sub habitat): wetland that accumulates peat. No streams coming in or out. Low nutrients. Carnivorous plants

Animals: Life histories timed around harsh winters. E.g., Moose mate in fall; have young in spring. E.g., snowshoe hares switch to buds and needles in the winter

Human Impacts: Logging. Introduced species (esp. Insects that kill trees). Air pollution

Correlation

________ does NOT equal causation.

Hyp Ha

________: A tentative statement about nature, the purpose of which is to suggest experiments (a ‘ best guess) Null Hyp H0: There is no significant relationship between observation and hyp.

Natural selection

________: organisms can change over generations if individuals with certain hertiable traits leave more offspring than others.

Definition of Science

a system of acquiring knowledge; or, the knowledge itself

Manipulative Experiment

higher power to detect differences, more control, more costly; you remove a top predator or mimic a natural occurring event in a lab or field

Dependent Variable

What is measured

Independent Variable

This is what is manipulated; or the effects of which you wish to determine

Confounding Variable

A variable other than your independent variable, that effects your dependent variable

Fitness

the number of viable offspring contributed by an individual to future generations

Two key observations of Natural selection

over production and variance

BACI Experiment Design

Before, After, Control, Impact. Allows you to take into account; differences among sites at the start, environmental changes over time

Control

1. A treatment against which one or more other treatments can be compared.

2. Identical except does not receive the manipulation under investigation

Randomization

1. Process of randomly allocating treatments and controls to experimental units

2. OR randomly selecting samples from the population of interest

Elements of a good experimental design

1. Control

2. Replication (sample size)

3. Randomization

Bias

A systematic error that can involve favoring of something or an outcome

Quasi-Experiments

(one or more key components missing)

1. Money

2. Logistics; rare animals, transportation issues

3. Ethical problems; what is it going to do to humans or animals

4. The independent variable is not manipulated by the researcher

5. Treatment and control groups might not be randomized

6. May lack a true control

Result of a Quasi-Experiment: Researcher is limited in what he/she can say

Two possible outcomes of competition between species with identical niches:

1. Extinction, or exclusion of one species

2. Change in one species to use different resources (“Ghost of competition past”)

Species can become resource specialists, minimize niche overlap Species can be generalists with high overlap, and competition

Competition

_____: Can result in evolution of niches

Human Impacts to Lakes

• Eutrophication (high nutrient conc.)

• Invasive Species

Replication

is having more than one experimental unit PER Treatment.

Greater replication

closer to true average, greater power to detect differences.

Sample size

# of experimental units per treatment (Tanks of fish)

Tundra

General location; two types

Arctic: south of polar ice cap

Alpine: high mountains

Climtae: Covered with snow and ice except in brief summer. Temp range -40 to 68F. Most ppt falls as snow. 5-10’’ ppt/year.

• Winter is long, bitter cold, litte or no sunlight, windy. 20 to 24 hours of darkness or sunlight spending on the time of year

• Summer: Brief growing season (less than 8 weeks)

Dominant vegetation: Grasses. Also mosses, dwarfs shrubs, lichens. Trees cant survive the cold, wind, permafrost, growing season

Soils: Forms slowly. Thin. Subsoil is permafrost: permanently frozen layer of gravel/sand/ice. Only top layers grow out. Melting snow and ice forms ponds; insects, waterfowl

Fire: not important

Animals: burrow under snow or ground. Hibernate, change color, thick fur

Human impacts: Climate change; melting glaciers and permafrost release of methane, increase in temp has been 2x 4x greater in the arctic than elsewhere. Starving polar bears. Oil drilling (fragile ecosystem). Mining of gold and diamonds

Alpine Tundra

Found at high elevation (versus latitude). No permafrost; soils better drained. Slightly higher amts of ppt: 12’’/yr. No 24-hr dark or light. Has trees!!!!

Animals: Yellow-bellied marmots, Big horn sheep, Ptarmigans

Human impacts: Air polution, errosion, eco tourism, oil drilling, ski resorts, mining

Formula for Photosynthesis

6CO2+6H2O→C6H12O6+6O2