Plant Ecology Exam 1

Define climate

The long term description of weather at a given location, based on averages and variation in moisture and temperature measured over decades

What angle does the earth tilt?

23.5 degrees

Define Solstice

The time or date (summer or winter) at which the sun reaches its minimum or maximum declination

Define Equinox

The time or date at which the sun is directly overhead the equator

What is the tropic of Cancer

The northernmost point on earth that gets sunlight directly overhead

What is the tropic of Capricorn

The southernmost point on earth that gets sunlight directly overhead

What is the Continental effect

Describes why and how interior regions further from the coast experience greater temperature variation that leads to colder winters and hotter summers, and inversely how maritime regions experience less temperature variation that leads to warmer winters and cooler summers

Define Heat Capacity

The amount of energy required to heat a substance by one degree

What is the Rainshadow effect

Most rainfall occurs on western facing slopes, as such, eastern facing slopes are left with dry air that warms as it moves down the slope and wicks up moisture off the earth's surface, creating dry arid conditions on east facing slopes

Describe Adiabatic cooling

Cooling that occurs as a result of changing pressure

What is the Coriolis effect

The apparent deflection of a moving object (associated with earth's rotation, i.e. a parcel of wind)

Define Succulence

The modification of stems or leaves for storing water

Define Sclerophyllous

woody vegetation with tough, leathery, and often small evergreen leaves adapted to survive dry summers, poor soils, and fire, typical of Mediterranean-type climates

Define Biosphere

An all encompasing term for the zone of life on earth

What are Biomes

Large biological communities shaped by the physical environment, and described by plant forms, deciduousness, and succulents

What defines a Tropical Rainforest

Wet year round, usually >200cm precipitation/year, emergent/super-canopy trees, and light being the most limiting factor

What defines a Dry Desert

Hot temperatures and very little precipitation year round

What defines a Temperate Grassland

Wide temperature variation, cold dry winters, water limitations mean they are generally treeless, and the majority of biomass is stored below ground

Deciduousness

the seasonal shedding of leaves

Morphology

the branch of biology that deals with the form of living organisms, and with relationships between

What are Emergent Trees

trees adapted to growing much higher than the average canopy that grow very fast

Why do we use plants to characterize biomes?

the dominant plant forms of a biome make up the large biological community, and are determined by factors like climate

Define Ultramafic (serpentine)

Soils that are low in nutrients and high in heavy metals, these soils have low productivity, low vegetation, and tend to be rocky

What is the Pleistocene

the geological epoch that ended around ~12,000 years ago known as the last ice age, characterized by glacial movements

What is Glacial Movement

Ice is heavy and pushes down on itself and the land, causing movement. If the ice is melting faster than it is moving, it causes glaciers to recede.

What are pothole lakes / glacial potholes

divots formed by glacial movement when melted ice chunks are left behind

What is Palynology

the study of pollen

Differential rates of plant movement in response to climate change

Wisconsin Glaciation

the last major ice advance of the Pleistocene Epoch

Milankovitch Cycle

describes the periodic changes in earth's eccentricity, obliquity, and precession that explain climatic shifts (ice ages and warming periods)

Eccentricity

the shape of earths orbit (orbital shape) with a cycle of ~100,00 yrs

Obliquity

earths tilt, with a cycle of 41,000 yrs

Precession

wobble (26,000 yrs)

Ruddiman’s theory

the Milankovitch cycle has been disrupted due to human impact (steep increase in rice cultivation and deforestation for agriculture)

Photosynthesis

6CO2+6H2O → C6H12O2+6O2

Respiration

C6H12O2+6O2 → 6CO2+6H2O

Ecotypic differentiation

the process by which ecotypes are formed. changes in the world that plants experience

Ecotype

genetically differentiated populations

Phenotypic plasticity

the ability of a genotype to produce phenotypically different traits - variation within the phenotypic expression of a genotype - differences caused by different environmental conditions & not genetics

Common garden experiment

growing plants from different geographical populations or species together in a single, shared environment to determine if trait variations are genetic (adaptive) or environmental (phenotypic plasticity). By removing environmental variation, researchers can assess local adaptation, evolutionary responses to climate change, and the traits of invasive species.

Reciprocal transplant

swapping two plants and planting them in different (each others) location

Metal tolerance

the ability of a plant to grow in soils with highly concentrated heavy metals

Describe the Wu and Bradshaw study

they found higher metal tolerance from old lawns, showing how evolution can occur on a much shorter time scale than previously thought

Haploid, Diploid

# of sets of chromosomes

Apomixis

any form of asexual reproduction

Agamospermy

seed production without meiosis

Bulbs, corms, rhizomes, stolons

different adaptations of plants for energy storage or spreading

Protogyny

male component matures earlier - avoiding selfing

Protandry

female component matures earlier - avoiding selfing

Distyly, tristyly

spatial separation of anthers and styles - these are different style lengths

Self-compatibility systems

• Gametophytic self-incompatibility: 

Individual 1 makes pollen a and b, individual 2 makes pollen a and c. ind. 1 wont accept pollen a from ind. 2 but will accept pollen c

• Sporophytic self-incompatibility - wont accept either

Dioecy/dioecious

Inbreeding

mating between close relatives

Inbreeding depression

a reduction in progeny fitness as a result of inbreeding

Cleistogamy, cleistogamous

a form of self-pollination where flowers remain closed, never opening to expose their reproductive parts

Myrmecochory

seed dispersal by ants

Vespicochory

seed dispersal by yellow jackets

what are the major types of dispersal mechanisms

• Wind

• Water

• Animals

  • Ingestion

  • Caching/hoarding

  • Adhesion

• Explosive/ballistic

• Passive

Stratification

the requirement of a cold period for germination

Scarification

the requirement of physical or chemical abrasion

What is a seed bank

the storage of dormant seeds below ground

What are the benefits of having a seed bank? Why do plants do it?

bet hedging! spread out risk over time, especially good for short lived plants

Seroteny

the release of seeds from some environmental trigger - almost always refers to heat

primary forest: ancient

forest not affected by human development

Dr. Beal’s experiment

20 bottles filled with 50 seeds from 21 species, buried one bottle every 5 years at first and now 20 years to see how long the seeds stay viable for

Population viability analysis

1. is the population stable, increasing, or decreasing?

2. what is the probability of extinction?

3. what is the best management strategy

Environmental stochasticiy

the random and unpredictable fluctuations in the environment that affect population dynamics and ecosystem stability

Age classes

Stage classes

Size classes

Extinction risk / extinction probability

small populations are at a greater risk of extinction, extinction probability decreases as population size increases

Sensitivity analysis

idk like how sensitive a species is for extinction prolly

investigates how variations in model inputs (e.g., vital rates, environmental factors) affect output, identifying key drivers for population persistence, management actions, and model uncertainty

Minimum viable population size

the smallest number of individuals required for a species to persist in the wild for a specific time

Allee effect

positive effect of density

density dependence

the dependent relationship between population growth and density

Negative density dependence

population growth slows as density increases

Positive density dependence

population growth increases as density increases

metapopulation

the larger group of smaller interacting populations

proportion of occupied patches

Nonequilibrium metapopulation

a set of spatially separated populations (patches) that do not maintain a stable balance between local extinction and colonization rates

Habitat fragmentation

the process where large, continuous plant habitats are broken into smaller, isolated patches

results in reduced pop sizes, increased extinction probability, and increased isolation

Importance of patch size and isolation

patch size and isolation heavily impact extinction risk

Matrix habitat

the area between smaller portions of fragmented habitats

edge effects

the changes in population or community structures that occur at the boundary of two or more habitats

Biotic vs. abiotic edge effects

Abiotic:

• warmer daytime/colder nighttime

• humidity changes/soil moisture

• light, sound, wind

Biotic:

• weeds, invasive spp.

• increased or decreased growth

• herbivory

Global patterns of patch size & edges

I think this is how 70% of earth's forests are kinda edge habitat

Extinction debt

Amount of anticipated extinction of species from a fragmented landscape

Edge effects example of Laurance (2000)

Mutualism

Commensalism

(+,0) one species benefits, the other is unaffected

Competition

(-,-)

Herbivory

(+,-)

Parasitism

(+,-)

Predation

(+,-)

Ammensalism

(-,0) one species suffers while the other is unaffected

Mycorrhizae

fungi that associates with plant roots (95% of vascular plants)

Arbuscular mycorrhizae

infiltrates/penetrates cell walls

Ectomycorrhizae

goes in between cell walls

Physical defenses

thorns, spines, prickles, tough hairs