UCM Ecology Exam 1

ecology

the scientific study of interactions between organisms and their environment

Ernst Haeckel

termed the phrase ecology in 1866

importance of ecology (three)

• improving the environment

• natural resource management

• public health

why ecology is important for improving the environment

• reducing pollution

  • EX] phosphorus in soaps and fertilizers allow for algae to grow and result in fish death

• non-native/introduced species

  • EX] feral pigs destroy acres of land and harm agricultural systems resulting in less food produced which leads to higher prices for us

why ecology is important for natural resource management

• maintaining biodiversity

  • EX] protecting endangered species while highlighting the importance of the common creatures as well in the ecosystem

• timber (role of fire)

  • EX] small prescribed burns can release nutrients into the soil and developed trees to promote quicker growth and encourages biodiversity, mimics the natural process

• fisheries

  • EX] take care of estuaries (where a river and ocean meet) which are important for reproduction, build fish ladders to help fish get around dams

• agriculture

  • EX] finding natural predators for pest to prevent crop destruction

why is ecology important for public health

• disease/viruses

  • EX] Lyme disease and Zika virus are the results of pest-spread diseases that thrive in warmer climates

• biomedical contribution

  • natural resources that have medicinal properties

  • EX] Taxol (tree) can be used for cancer treatments

• natural services

  • EX] filtering by wetlands allows for cleaner water

levels in ecology from biggest to smallest

1. biosphere

2. region

3. landscape

4. ecosystem

5. community

6. interactions

7. populations

8. individuals

individuals

one organism

population

two or more individuals from the same species

interactions

two individuals interacting, species doesn’t matter

community

two or more species

ecosystem

all the organisms in a given area as well as the physical environment in which they live

nutrient flow

region

global processes

biotic factors

• LIVING components of the ecosystem

  • EX] predators, prey, food, shelter (trees, etc.), competitors

abiotic factos

• NON-LIVING components of the ecosystem

  • EX] wind, temp, soil, light, rain, climate

producer

produces own energy without eating other organisms

consumer

obtains its energy by eating other organisms

Net Primary Production (NPP)

amount of energy producers capture by photosynthesis - their metabolic heat (metabolism)

EX] plants will store extra energy by increasing biomass AKA growing bigger, producing roots, producing fruits, etc.

metabolism

chemical process that occurs within a living organism in order to maintain life (requires energy)

biomass

total mass of organisms in a particular area

evolution

change in allele frequencies (genetic characteristics) of a population over time

adaption

characteristic of an organism that improves its ability to survive or reproduce

natural selection

Process which individuals with certain characteristics tend to survive and reproduce at a higher rate because of those characteristics

• natural selection can lead to evolution by changing allele frequencies in a population

observations and questions

make connection between unrelated observations using sight, sound, touch, taste and smell and using existing knowledge and experimental results

hypothesis characteristics

• Tentative explanation for observation(s) (cause-effect)

• Testable- must be able to collect data
• Cannot be proven true
• Accepted if enough evidence supports it
• Leads to predictions (if-then statements)

data collection

• conclusions drawn from the data

• two primary sources

  • observations (natural experiment)

  • controlled experiment

analysis

• Does evidence (data) support or falsify the hypothesis?

• Most interesting results are often unexpected

• Rethink hypothesis (feedback)

peer review

• submit results to journal

• reviewed by independent scientists

sample size

number of individuals in study/each treatment

independent variable

biologist manipulate this variable

dependent variable

may respond to independent variable

standardized variable

any variable held constant

controls

untreated group

important aspects of an experimental design

• sample size

• independent variable

• dependent variable

• standardized variable

• control

• replication

• randomization

biomes

• major divisions of terrestrial environment

• distinguished by their predominant plants

• associated with particular climates

global climate patterns

a combination of temp, moisture, precipitation and winds

• driven by solar radiation

greenhouse effect

1. sunlight penetrates atmosphere, warms Earth’s surface

2. solar radiation is absorbed by the surface, escapes back into space, or molecules or greenhouse gases absorb and warm the lower atmosphere

3. greenhouse gas increase = temp increase

solar radiation

creates season relative to the position of the sun and the Earth’s tilt

average global temperature

hot at equator, cold at poles

Saturation Vapor Pressure

maximum amount of water the air can hold (temperate effects humidity)

solar-driven air circulation

hot air rises, cold air sinks causing dry conditions

average terrestrial precipitation

• high precipitation at 0 and 60

• low precipitation at 30

Coriolis effect

spin of Earth deflects win direction

wind functions

• dispersal/migration

  • EX] can blow seeds, animals save energy flying with the wind

• carries moisture

• catastrophic

  • EX] tornado, hurricanes, wind storms

regional climate patterns determined by:

• continental location (distance to water)

• topographic features (mountains)

continental location

similar temperatures year round when by the water

east and west facing slopes (mountains)

mountains → rain-shadow

• rain-shadow

  • one side is wet = windward

  • one side is dry = leeward

1. intercept air masses, cause them to rise

2. cooler atmosphereic temps cause vapor to condense

3. vapor becomes precipitation

north and south facing slopes (mountains)

• south = more sunlight, less precipitate, high evaporation rates

• north = less sun, more precipitation, low evaporation

urban climate

cities produce their own climate (heat dome/island)

• man-made structures absorb more heat

• releases heat at night

• air pollution traps heat at surface

• buildings alter air flow

• lower humidity

albedo

amount of radiation reflected by a surface

EX] light surface = high albedo bc light reflects

dark surface = low albedo bc light is absorbed

climate diagrams

temperature on left, precipitation on right

soil properties

texture (particle size) → water-holding capacity → cation exchange capacity (nutrients)

soil texture

relates to pore space between particle

• movement of air and water

• water storage capacity

• nutrient exchange

• penetration by roots

coarse soil water holding capacity

high permeability

fine soil water holding capacity

low permeability

saturated soil

amount of water that exceeds soil’s pore space

field capacity

water remaining in the pore spaces after gravity has drained the rest away (perfect conditions)

wilt point

point at which a plant can no longer withdraw water from the soil

available water capacity (AWC)

amount of water between field capacity and wilt point (water this is available to plants)

• field property - wilt point = AWC

loam

best soil for crops, equal parts sand, clay and silt

function of soil

atmosphere composition

78% Nitrogen (N2)

21% Oxygen (O2)

1% others

mechanical weathering

increase surface area, roots can force their way through rocks

chemical weathering

release of soluble nutrients

leaching

movement of dissolved matter and minerals from upper to lower levels

decomposition

organic material broken down

EX] primarily plant matter, leaf litter

Humus

• contains nutrients

• increases water holding capacity

• prevents compaction

climate influence on soils

• processes most rapid in warm wet conditions

• little decomposition in aquatic systems

• most nutrients found in living biomass

• processes slower in higher latitudes

soil abuse

• poor agricultural practices

• removal of vegetation

• use of pesticides

• use of fertilizers

bad fire

• kills organisms

• increases soil erosion and mudslides

• exposes soil to sun

good fire

• adds nutrient to soil

• maintains community structure

• “fire adapted” plants

• can increase community diversity

tropical rainforest

• soil = nutrient-poor

• High temperatures, high precipitation

• face deforestation/slash and burn

• broadleaf evergreen trees

• vertical dimension

  • epiphytes = plants growing on other plants

• highest biodiversity

• food (maize, rice, bananas, sugarcane)

• prescription drugs

• produce 20% of the world’s oxygen

• carbon sequestration

• equator

  • ex) brazil, congo, Malaysia

tropical dry forest and savanna

• strongly influenced by abiotic factors

  • dry season, fire

• High temperatures, wet and dry season

• seasonal migrations are common

• termites = 10% biomass

• soil good for agriculture

• Mexico, India, Australia

desert

• low in organic matter

• higher salt content

• space plant cover, succulent plants

• low abundance, high diversity

• fragile habitat

• good for recreational areas and solar power

• Arizona, chad, Mongolia

mediterranean woodland and shrubland

• cryptogamic crust

• Mild wet winters, hot dry summers

• high biodiversity

• plants are small evergreen and adapted to drought and fire

• hugely impacted by humans

  • produces olive oil and wine + ppl love living here

• San Diego, Italy, Australia

temperate grassland

• Warm wet summers, cold drier winters

• deep fertile soil

• 67% of biomass is underground

• dominated by herbaceous vegetation (formally herds herbivores)

• regular fires prevent growth of trees

• less than 5% remains

• Kansas, Russia, China

temperate forest

• Warm wet summers, cold drier winters

• largest organisms (high biomass)

• fertile soils

• 1-2% remain

boreal forest

• Cold winters, mild summers, more precipitation

• permafrost

• low biodiversity

• breeding site for tropical wintering birds

• evergreen conifers

• no historic human impact until recent

tundra

• Cold and dry (very short growing season in summer)

• layer of permafrost

• low temps = slow decomposition

• 14% of the Earth’s carbon

• herbaceous plants

• lots of insects but not diverse

• effected by oil and pollution

mountain climate

as elevation increases, temperature drop sea precipitation increases

lotic system

moving water

• higher oxygen content

• terrestrial (leaves, woody debris, dead animals)

• in-stream (rooted vegetation, algae, dead animals)

• affected by dams (→ fish ladders) and bridges

lentic system

standing water

• lower oxygen content

  • limiting factor for organisms

  • cold water = higher oxygen

river continuum concept

stream flows downslope and increases in size

• nutrient input from adjacent vegetation decreases

• stream bed particles size decrease (boulders→sand)

• more aquatic plants downstream

shredders

process coarse organic matter AKA tear up leaves

EX] caddisflies

collectors

collect fine particles from the water (from shredders)

EX] fly larvae

grazers

feed on aquatic plants and detritus, found on rocks and woody debris

flood pulse concept

• floodplain: seasonal river flooded areas

• flooding is a natural/required process

• important for nutrient exchange

how is oxygen lost in lentic systems

• increased temp

• respiration of organisms

• aerobic decomposition

biological oxygen demand (BOD)

the amount of dissolved oxygen in an aquatic system that is required for respiration by decomposers

oligotrophic lakes

lentic systems - nutrient poor

• few plants/algae

• deeper

• low turbidity (clear)

• high oxygen levels

• cooler

eutrophic lakes

lentic systems - nutrient rich

• plant/algae growth

• shallow

• high turbidity (sediments)

• low oxygen levels

• warmer

marsh

wetland dominated by herbaceous plants

swamp

wetland dominated by woody plants

human impact of aquatic systems

• introductions

• pollution

• macroinvertrbrates (index of biological integrity)

benefits of wetlands

• recharges groundwater aquifers

  • holds and discharges water slowly into aquifers

• reduce the intensity of flooding

  • 5% of wetlands can reduce flood flows by 50%

• water filtration systems

  • vegetation takes up excessive nutrients and heavy metals

  • people treat urban wastewater by running it into natural or specially-created wetlands

  • sources of economic gain (wood products, horticultural peat, cranberry production)

• habitat for a rich diversity of wildlife

• protection against mangroves

marine

• more salt

• more stable temp

• oxygen available

• very different organisms

oceans

cover 71% of Earth’s surface

• more uniform than terrestrial

ocean garbage islands

floating material concentrates in area between currents

upwelling

areas with high nutrients

• nutrients and light required for productivity

estuaries

junction of a river and the ocean where fresh water enters the ocean, freshwater flow + influx of salt water

• important reproductive sites

• crucial feeding areas for birds

• threatened by sewage

• MOST PRODUCTIVE AQUATIC SYSTEM