ESS - ecology | Quizlet

what is biosphere made up of

hydrosphere, lithosphere, atmosphere

ecosystem

comprise communities and their non-living environments as a single unit

how to determine the health of an ecosystem

biodiversity, productivity, cyclical movements of energy

community

group of populations of diff species living in same area & interacting

factors of a community

Symbiosis, competition, predation

population

group of people living in specific area, interbreeding

pop. dynamic

growth rates, migration

individuals

smallest unit in ecological hierarchy → Individual sing organism capable of independent survival

species

group of organisms that can interbreed & produce fertile offspring

taxonomy

the classification system for organising Earth's diverse life forms

Linnaean system:

identifies organisms and predicts characteristics, aiding in the study of biological relationships and evolution.

Binomial name:

each species has a two-part specific name genus (group with similar traits & species name → written in latin, italicised or underlined

ecological importance:

knowing local species helps understanding their role in ecosystems & need to protect

key elements of classification

hierarchical structure & binomial nomenclature

Binomial Nomenclature

Uses genus name & species name to form scientific name

issues with taxonomic system

Nature doesn't always conform to categories we define

- Species exhibit characteristics spanning multiple groups

tools for species identification

-dichotomous keys & DNA analysis to distinguish species

-specimen samples

dichotomous key

series of choices to final identification

key characterisitcs of a pop.

interbreeding, boundaries(spatial & temporal), multiple populations per species (geographic or behavioral barriers)

importance of population studies

conservation, resource management (sustainable use of resources - prevent pop. imbalances)

biotic factors

competition

predation

symbiosis

disease

abiotic

temp

water

soil type

light

temp (abiotic)

thermal limits - determine which organisms capable of surviving

soil type (abiotic)

texture, PH & nutrient content influence distribution of plants > animal pops dependent of plants

light (abiotic)

amount & intensity - where plant species grow

Altitude & Geography (abiotic)

Higher altitudes may have cooler temperatures & less oxygen → limit which species thrive

what is the impact of temperature

influences growth rates, reproduction & survival rates

wind (abiotic)

affects the rate of transpiration in plants, seed and pollen dispersal, and can physically shape the structure of plants and the landscape.

pH (abiotic)

level of soil & water → nutrient availability & toxicity

dissolved oxygen (abiotic)

dissolved oxygen in water is crucial for aquatic life

Ecological niche:

abiotic & biotic conditions → species to survive, grow, reproduce & functional role in ecosystem

why is understanding niches important

aids in habitat management & helps predict how a species may react to environmental shifts

Intraspecific competition:

competition between members of the same species.

Intrespecific competition

competition between members of different species

parasitism

Host provides habitat & food for bacteria → causes disease in host

(Symbiont benefits & host is harmed)

Mutualism

Benefit both interacting species

Disease

reduces population size, affect genetic diversity & trigger behavioural changes in affected species

herbivory

Interaction occurs when herbivores consume plant material→ plant population dynamics → evolutionary adaptations in plants

predation

predator feeds on prey

ecological consequences of interactions

determine distribution & abundance of species, structure food webs & drive dynamics of energy & nutrient cycles w/in ecosystems

behavioural consequences of interactions

Predation & parsitims → evolution of complex behaviours such as group living (safety in numbers) or nocturnality in prey (avoid diurnal predators)

evolutionary consequences of interactions

Interactions → evolutions, 2 or more species reciprocally influences each other's evo.

carrying capacity

maximum pop size of species that an environment can sustain indefinitely

key aspects of carrying capacity

resource limitation, dynamic nature (fluctuates due to environmental changes)

factros influencing carrying capacity

food, water, habitat space, climate, human impact

what does carrying capacity do

aids wildlife management, setting sustainable limits & restoring habitats to support species pops.

density dependent factors

competition for resources, increased predation, disease transmission, density-independent factors, integration, negative feedback mechanisms

how are populations regulated

density-dependent factors & negative feedback mechanisms

density-independent factors

Natural Disasters: wildfires & floods reduce pop. sizes regardless of density.

Climatic Changes: droughts & cold snaps affect survival of all

integration

Combined Effects: Density-dependent factors regulate long-term pop. stability, while independent factors = sudden changes.

When does exponential growth occur? (J curve)

when pop. grows rapidly w/out limitations

characteristics of a j curve

Assumes unlimited resources

No competition

Ideal conditions

All individuals survive & reproduce

→ rapid increases

when does logistic growth occur (s curve)

Growth slows as pop. nears carrying capacity

characteristics of an s curve

Density dependent factors + (competition, predation & disease) as pop. grows → stabilising size near the carrying capacity

what is a boom

rapid growth

what is a bust

sharp decline

when does bust occur

after pop. overshoots carrying capacity - end up falling below initial levels

accelerated growth (human pop)

Human pop. growth surged from tech, medicine & agricultural Advancements → removes natural limits

types of technological advancements

health improvements (vaccines & antibiotics)

agricultural innovations (high yield crops & synthetic fertilizers)

reduction of natural predation (safety enhancements)

environmental consequences of humn pop. growth

resource depletion, habitat destruction, & pollution

future considerations

sustainable policies & planning (renewable energy, recycling, biodiversity preservation)

what concerns are there for human's sustinability

because of humans ever-evolving nature, it is difficult to define clear carrying capacity = limiting sustainable planning

how to calculate carrying capacity

calculated as reciprocal of eco. Footprint → measure of how many people an area can sustain based on current consumption

random sampling

Selecting random points in habitat to collect data,

Avoid bias in selection

Everyone in pop. has = chance to be included

application of random sampling

homogeneous environments (distribution of pop. uniform)

advantages of random sampling

Unbiased

Suitable for large pops.

disadvantages of random sampling

May not have access to some of the sample points

Large study areas → sample point may miss some places

systematic sampling

Selecting samples from fixed interval along predetermined path/grid

- Sampled area is evenly covered

application of systematic sampling

environments where species evenly distributed

advantages of systematic sampling

Easier to apply than random sampling - no need for grid

Can cover whole study area

disadvantages of systematic sampling

May be biassed because places have different chance of selection

Patterns may be missed or exaggerated

transect sampling

A line (transect) placed across habitat → organisms along line sampled to study how physical factors (temp. & light) affect distribution

types of transects

line & belt

application of transects

useful for studying species distribution across environmental gradients

from shore to deeper lake areas

advantages of transects

Analyses spatial patterns along gradients

disadvantages of transects

May not represent entire habitat in heterogeneous environments

purpose of quadrat sampling

study biodiversity & species distribution

method of quadrat sampling

quadrats placed randomly or systematically within a habitat

- Species within each quadrant identified & counted

usage of quadrat sampling of quadrat sampling

stationary organisms (plants) + applicable slow-moving animals

qs counts

Number of species in an individual area

qs population density

total number of a species in all quadrats population density/area of one quadrat × total number of quadrats

% frequency

number of actual occurrences/ number of possible occurrences

advantages of quadrats for assessing number of individuals, % frequency & population density

- quick easy method to apply

- accurate w/ large species

- good for comparisons over time or space