Ecology Exam 1

Dr. Paul Ode's Exam 1 for LIFE 320

Exploration and Discovery

First stage of Scientific Inquiry

Make observations, Ask questions, Review Literature

Exploration and Discovery

Testing Ideas

Second Stage of Scientific Inquiry

Generate Research Questions and Hypotheses

Design Studies

Collect and Analyze Data

Testing Ideas

Community Analysis and Feedback

Third Stage of Scientific Inquiry

Design study with replicates

Engage in peer review

Build theories that can be tested

Community Analysis and Feedback

Benefits and Outcomes

Fourth Stage of Scientific Inquiry

Address societal need

Inform policy

Solve problems

Build knowledge and understanding of natural phenomena

Benefits and Outcomes

Ecology

the study of ecological systems from a natural science perspective

What ecologist do

Engage in a systematic effort to understand and describe the natural world using accepted scientific inquiry methods

Environmental Science

the study of human-ecological systems from both natural and social science perspectives

Environmentalism

social or political viewpoint aimed at preserving natural environmental systems

Challenges of ecological research

Experiments are not always possible

• Scale is too large or small (time and space)

• Causal factors are difficult to separate

Correlational observations

Microcosms/ Mesocosms

Allow researchers to replicate key features of a system at a small scale

Ensures that data can be consistently collected

Mathematical models

Portray system with equations to generate predictions in a more refined way

Test hypotheses using simulations (informed by observations)

What are some questions ecologists might ask

where do organisms occur, how many occur there, \n and why?

Biosphere

Global Processes

includes all ecosystems and landscapes on Earth \n •wind and water currents, migrating organisms ***move*** energy and nutrients (matter) among ecosystems and landscapes \n •energy comes from the sun and is lost to space (it flows) \n •matter cycles (for the most part)

Landscape

Ecosystem interaction

multiple ecosystems connected by movement \n of individuals, populations, matter, energy

may include both aquatic and terrestrial \n ecosystems, natural and disturbed habitats

Ecosystem

one or more communities interacting with their physical/chemical \n environment

focus is on the ***flow*** of energy and ***cycling*** of matter between physical and biological components

No distinct boundaries

Communities

all the populations in a particular area

Artificial Boundaries

Interactions among species: interspecific competition, resource–consumer interactions

Populations

group of individuals of the same species living in the same area

Geographic or Political Boundaries

five unique properties: geographic range, \n abundance, density, change in numbers, change in composition

variation in time and space in the number, density, and composition

Five unique properties of Populations

geographic range, \n abundance, density, change in numbers, change in composition

Individuals

alters the flow of energy and chemical elements through the \n environment

must acquire resources, get rid of waste

\

energy and matter in equals energy and matter out

ecological systems are stable (persist) when

producers (autotrophs)

convert solar energy (photosynthesis) or chemical energy (chemosynthesis) into organic compounds (most algae & plants, many bacteria)

consumers (heterotrophs)

obtain energy from other organisms (herbivores, predators, parasites, parasitoids, scavengers/detritivores/decomposers)

mixotrophs

obtain energy from photosynthesis and consumption of organic carbon/other organisms (e.g., many algae, carnivorous plants)

herbivores

consumers of primary producers (plants); typically, don’t kill the plant (sometimes considered plant parasites)

predators

kill and consume multiple prey (herbivores, other predators, etc.) to complete development and sustain oneself

parasite

live on or in other the body of another organism (the host) – just one host is required to complete development; parasite rarely kills its host

parasitoid

similar to parasites in that they develop in or on a host organism, similar to predators in that they always kill their host – most species are wasps and flies (at least 150,000 described species!)

scavengers

consume dead animals

detritivores

break down organic material into smaller particles

decomposers

break down organic material into simpler compounds and elements

competition

negative effects on two species that require the same resource to survive, grow, reproduce

mutualism

interaction between two species that is beneficial to both (e.g., plant-pollinator, ant-plant mutualisms, lichen (algae and fungus)

commensalism

one species benefits from the relationship, the other species is neither helped nor harmed (e.g., epiphytic plants and host plant, phoretic insects/mites on larger animals)

symbiosis

any physically close relationship between two organisms; may be mutualistic or not (e.g., parasitism, commensalism

weather

hour-to-hour, day-to-day variation in temperature & precipitation; e.g., tomorrow’s weather forecast for Ft. Collins is 30% chance of snow, mostly cloudy with a high near 0˚C

climate

typical atmospheric conditions that occur throughout the year; e.g., climate of Colorado is semi-arid (38cm precip. annually), cold and dry in winter, cool & moist springs, hot and dry in summer

albedo effect

light colored surfaces reflect more solar radiation back to space

dark colored objects reflect very little solar energy back to space.

albedo

fraction of sunlight reflected back to space

Hadley Cell

Warm moist air rises because it’s less dense.

It cools as it rises releasing the water as rain.

The cold dry air is pushed out towards the poles by the new rising air.

It then settles on the earths surface and begins moving back towards the equator collecting moisture as it does

ITCZ (intertropical Convergence Zone)

where the two Hadley cells converge

Polar Cells

air rises at 60˚N and 60˚S, drops moisture

• cool, dry air moves to poles where it drops and cycles back to 60˚N and 60˚S

Ferrel Cells

indistinct air movement – mixes tropical and polar air

rain shadows

high mountains force winds upward; as they cool, they drop rain, leaving warmer, dry air on the other side

proximity to coast

coastal regions of continents generally have more moderate climates (less hot or cold extremes) than continental interiors

ponds & lakes

fresh water, with at least some areas too deep for emergent vegetation

littoral zone

limnetic zone

profundal zone

Benthic zone

Littoral zone

around the edge of a body of freshwater that has roots

temperate ponds & lakes

stratification during summer

spring turnover & fall turnover – cycle nutrients

winter – aquatic organisms survive, because ice floats over 4˚C water which is less dense

streams & rivers

flowing fresh water (lotic) •

tend to be species-poor, external source of organic matter (allochthonous), high in O2

species-richh, plant & algae provide organic matter (autochthonous), lower in O2

freshwater wetlands

standing fresh water for at least part of the year, emergent vegetation at all depths • swamps contain trees • marshes have emergent non-woody vegetation • bogs have acidic waters (e.g., peat mosses, carnivorous plants)

saltmarshes

are saline – emergent non-woody vegetation

mangrove swamps

contain trees in tropical and subtropical coasts

estuaries

where rivers meet oceans

coral reefs

marine

shallow, tropical waters

animals (related to cnidarians) that have mutualistic association with algae

ocean zones

intertidal zone neritiz zone photic zone aphotic zone

neritiz zone

to a depth of 200m, the continental shelf

photic zone

to 200m – enough light for algal photosynthesis

aphotic zone

no light - but chemosynthetic bacteria can act as primary producers that support consumers, other animals are detritivores

Terrestrial biomes

categorized by their dominant plant growth form

Aquatic Biomes

categorized by flow, depth, and salinity (primary producers ALGAE not plants

Polar Ice caps

______ don’t have plant life so not terrestrial biomes

Biomes

Geographic regions that contain communities of organisms with similar adaptations

westerlies

surface wind moving towards poles (e.g., from 30˚N to 60˚N or 30˚S to 60˚S) will move faster than the Earth’s surface

Coriolis effect

Because the earth rotates , the path of any object moving north or south is deflected

Is the predominant cause of air circulation along Earth’s surface to be deflected

gyres

large oceanic circulation patterns; clockwise in the N hemisphere, counterclockwise in the S hemisphere

upwellings

upward movement of ocean water as surface waters move away from continent – bring up nutrients from ocean depths – location of major commercial fisheries; generally, on the west side of continents.

Ecosystems

At what ecological level do we typically focus on the flow of energy

solar energy

What is the source of virtually all energy flowing through ecosystems?

primary productivity

energy: joules/m2/year; or carbon: g C/m2/year

standing crop

biomass of producers (plants, algae, etc.) present at any given time

NPP = GPP – respiration

How do we find GPP and NPP

secondary productivity

secondary productivity

NPP

is the amount available to consumers

Remote sensing

chlorophyll reflects green wavelengths; absorb blue and red

Secondary Productivity

Herbivores gather energy by ingesting producers. Of the energy gained via ingestion, some is lost in the form of egested energy, which represents the indigestible tissues of the producers. The rest of the energy is assimilated. OF the assimilated energy, some is used for respiration. The rest is used for growth and reproduction, which is _______

terrestrial NPP

is driven by temperature, precipitation, & nutrients (N & P)

aquatic NPP

is driven by temperature, light, & nutrients (N, P, Si, Fe)

HANPP

____ = amount harvested (used + unused) + land use change

1 Consumption efficiency

(consumed energy)/(net production of lower trophic level)

2 Assimilation efficiency

(assimilated energy)/(Consumed energy)

Net Production efficiency

(net production energy)/(assimilated energy)

Ecological efficiency

(net production energy)/ (net production energy of lower trophic level)

Aquatic Terrestrial

____ ecosystems typically support more trophic levels than ______ ecosystems

Aquatic Terrestrial

Ecological efficiencies: ____ >>> _____

Hydrological Cycle

Water evaporates from the ocean

Moves to land via winds

Precipitates

runs ground water and rivers

back to ocean

0\.015

what is the percentage of freshwater relative to other sources.

96\.5

Oceans hold __% of the earths water

3

Ice groundwater and freshwater make up __% of the earths water

solar energy

What drives the hydrological cycle? evaporation & evapotranspiration (water from plants to water vapor)

Carbon cycle

e is tied to flow of energy (photosynthesis vs. respiration drives the ____)

levels drop down in the northern hemisphere in the atmosphere during the summer because of the photosynthesis of plants in the warmer months.

Methane

CH4 ; GWP of 56 (56 times the global warming potential of CO2)

mineralization of organic compounds, gut fermentation of termites, ruminants

Nitrogen Cycle

N2 forms 78% of atmosphere

impt. component of amino acids (proteins) and nucleic acids (DNA, RNA)

nitrogen fixation

certian bacteria (Azotobacter, Rhizobium), lightning convert N2 to NH3 or NO3 - (useable by producers & consumers)

denitrification

conversion of nitrates to nitrogen gas; under anaerobic conditions (e.g., sediments) conversion of nitrates (NO3 - ) to nitrites (NO2 - ) and then to nitric oxide (NO); NO is then converted to nitrous oxide (N2O) which then to N2

Phosphorus Cycle

doesn’t have a gaseous phase

mostly accumulates and cycles within the ocean

ocean & sediments, terrestrial vegetation, rocks, soils all significant phosphorus pools

assimilation

uptake of NH4 + or NO3 - by producers & consumers

mineralization

breakdown of organic compounds into inorganic nitrogen by fungi (plants) and bacteria (animals)