Ecosystems part 2

what does temperature directly influence

the rate of chemical reactions

what do warmer conditions increase

• the likelihood of collisions

• impact energy

when are chemical reactions favourable

when they pass an energy activation barrier

what things in macromolecules are subject to change in kinetic energy

bonds

what are the potential change in bonds

• amino acids (protein shape)

• membrane components

what biological consequences are there towards the effects of temperature

abnormal protein function, membrane fluidity, and cellular functions

what do Endotherms do

regulate the body temperatures independent of the ambient environment

what are some things that endotherms regulate

• heat derived from metabolism

• ~ 1% of described species

what are ectotherms

body temperatures conform to the ambient environment

what are some things ectotherms conform

• heat derived from environment

• ~99% of described species

what can performance be

any rate or time-dependent metric of life

what are some bullet points of performance

• shell deposition of corals

• swimming speed of fish

• oxygen consumption rates

• growth rates

what do organisms experience

physiological effets of environnemental temperature

what does temperature greatly influence

the distribution and types of organisms

what do endotherms maintain

near optimum distribution of environmental temperature

what do ectotherms usually have

seek optimum distribution and type of organism

what types of temperature is the deposition of calcium carbonate (skeleton) on coral reefs

temperature dependent

when happens to coral reefs in warmer temperatures

it accelerates

when happens to coral reefs in colder temperatures

suppressed

what happens in warm-water coral reefs

the distribution limited to regions with 20 degrees average daily temperature in the coldest months of the year

are there any cold water corals

yes, in nova Scotia

how many spaces are there in cold-water coral reefs

25-30 species

how deeps and cold are cold-water reefs

200-1300 meters deep and 3-8 degrees Celsius in temperature.

how much do coral reefs grow and how long do they live

they grow 1 cm a year, and can live for decades

what are foundation species

dominates in terms of abundance; here, provides habitat for other species

what type of relationship do collars have with algae housed within their body that started ~ 210 million years ago

a mutualistic relationship

what do corals provide algae with

a home and nutrients (CO2, ammonia)

what does algae provide corals with

oxygen, glucose, and other nutrients

how fast do Coralas with algal symbionts deposit calcium

10 times faster than species of corals that lack algal symbionts

what happens when water temperatures are too high

algal symbionts can die or become toxic to the coral leading to their ejection (bleaching)

what happened to most corals without algal symbionts

corals cannot meet their energetic demand

what was the mass bleaching event in 2016

elevated water temperatures of as little as 2 degrees celsius for a few killed 50% of the corals in a region of the Great Barrier Reef (change in weather patterns brought in warmer waters can coral regain symbionts

can coral regain symbionts

yes

what happens after 3 months when coral regained symbionts

some of the corals had taken up a more heat-tolerant alga

what can new symbionts be tolerant to

stress, although they may not offer less food to the corals

what is a promising topic for corals

probiotics

what are low temperatures subject cells to

frost and ice damage; can rupture

what do animals usually do

seek shelter or migrate

what do plants generally must endure

chills - particularly risky for plants producing poisonous secondary metabolites

what does white clovers produce and store

cyanide within intracellular vacuoles

what does frost do

ruptures vacuoles, releasing cyanide into the plant tissue

when does cyanide production reduce

cold zones

what percentage of a wood frogs body can freeze without suffering injuries

~65%

what does freezing trigger in wood frogs

breakdown of glycogen

what do extracellular sugar slow

freezing rates

what do intracellular sugar slow

limits dehydration

where does ice form

around, but not inside cells

wood frogs blues being able to freeze ~65% of their body prevents what

prevents thawing cells from rupturing

what can high temperature physically damage

cellular components but can be necessary to complete life cycles

what do heck pine and giant sequoia require

frequent low-intensity fires to reproduce successfully

what must melt to release seeds (jack pine and giant sequoia)

Resin surrounding cone

what does a fire do to jack pine and giant sequoias

clear out competition near base of tree

what are keystone species

species that have a major effect on shaping an ecosystem, disproportionate to their abundance of biomass

what does prescribed burns in Australia cause

• decrease “tinder” and reduce wildfire risks

• light enters forest easier, favouring small plants

• damages large trees, small mammals, reptiles, insects

what are some organisms that use temperature-dependant sex determination

snakes, most lizards, Most turtles and crocodilians

what does incubation temperature activate

sex-determining genes

what happens after the gene expression pattern is set

the sex is fixed (irreversible)

what type of pattern occurs

the pattern is highly variable across members

for leather back turtles, what do different temperatures change in the change of being male or female

• low termperature <29 C = males

• 29.5 C = 50:50

• high temperature >30 C =86 °F females

for green turtles, what do different temperatures change in the change of being male or female

white sand: cooler temps (males, <28 C)

dark sand: warmer temps (females, >30 C)

for crocodiles, what do different temperatures change in the change of being male or female

• <30 C females

• 31 C = 50:50

• >32 C males

• varies amoung species

where do salt concentration vary

widely, in aquatic ecosystem

what do salt concentrations effect

• water density

• thermal capacity

• biochemistry

• availability of nutrients and metals

• biotic distributions

what does precipitation replenish

freshwater systems whose run-off carries dissolved minerals into the ocean

what does evaporation leave behind

minerals, and concentrating salts

what is the osmotic balance

ensures optimal levels of salts and water across cells and tissues in the body

what does the movement of water across the cell membrane do

balance solute (salt) concentrations

what is essential to balance for normal cellular functions

osmotic blance

what is passive transport

Osmosis

what is a hypotonic solution

there is not enough dissolved stuff in fluid

what is an isotonic solution

there is just enough dissolved stuff in fluid

what is hypertonic solution

too much dissolved stuff in fluid

where does water move

hypertonic area

what are some characteristics of freshwater fish

• hyperosmotic

• gain water by osmosis (e.g., water crosses into gills)

• freshwater fish do not drink water

• lots and lots and lots of dilute urine

what is hyperosmotic

more salts in their tissues than in the surrounding environment

what are some characteristics of saltwater fish

• hypo-osmotic

• lose water by osmosis (water crosses out of gills)

• saltwater fish drink lots of seawater

• very little urine but very concentrated

what is hypo-osmotic

less salt in their tissues than in the surrounding

how do organisms cope with ambient salinities

they have several strategies

what do osmoregulators maintain

the internal fluid osmolality independent of the environment

what are hyprregulators

internal fluids are maintained above ambient osmolality

what are hypo regulators

internal fluids are maintained below ambient osmolality

what are osmoconformers

internal fluid osmolality matches the enviroment (most marine invertebrates)

how many terrestrial plants are adapted for high salinity ecosystems

few terrestrial plants

what are halophytes

species that tolerate higher salt concentrations in their cells than regular plants

how are salt bushes used

In environmental remediation, salt from contaminated sites

what do spartina salt marsh hay have

salt glands and excrete salt onto the surface of their leaves

what is PH

the concentration of hydrogen ions

what is 1 unit of change

10x acidity

what are factors that effect pH of soil and water

Carbon dioxide (reparation, bacteria….), organic matter, geology, air pollution (sulfur dioxide), water from abandoned, coal, mines acid rain, burning, long-term clear cutting

what is the pH of normal rain water

5.6

what ph do most plants thrive in

soil of ph of 6.5 because there is a better availability of nutrient

what has a higher ph and richer (more diverse) flora

alkaline soils, chalk and limestone

what are ecosystem services

the benefits people obtain from an ecosystem

what are balsam fir and white ash

sensitive trees

wha are balsam fir and white ash important members of

Acadian forest

what is the optimal ph for most freshwater fish

between 6.0 and 9.0

what happens when there is a low ph Level in aquatic life

• alters water chemistry, increasing the availability of toxic metals (mercury)

• changes gill structure, decreases survivorship of embryos, changes hormone production in males, decreases salt tolerance in smolts (the life stage that goes to the ocean), decreases ability to detect predators