Lesson five Flashcards
How does temperature influence animals?
Influences growth of individuals and distribution of species
What is macroclimate?
Is determined by patterns of air and water circulation and other forces which interact with the local landscape to produce a microclimate. Macroclimate is defined as typical weather for an are (based on weather for the past few years)
What is microclimate?
climatic variation on a scale of a a few Kms, M, or even cm. Which is usually measured over short periods of time. microclimate is influenced by elevation (altitude), vegetation, soil, etc.
Where are temperatures usually lower?
Temperatures are generally lower at higher elevation. Atmospheric pressure decreases with elevation. at altitude there is less atmosphere to trap and radiate heat back to the ground. Topographic features create microclimates that would not occur in a flat landscape.
What is the coolest aspect in the northern hemisphere?
The north facing sides of mountains and valleys are shaded, coller, and retain moisture longer. In the southern hemisphere the south facing aspects are cooler.
what factors can affect ground temperature?
the colour of the ground and then the presence of any snow or vegetation that covers the ground
High albedo vs low albedo
High albedo means that the object reflects all visible colours (aka white) and black items absorb all visible colours and have low albedo.
can albedos change?
yes, depending on vegetation as well as they are not fixed to the properties of the landscape so they will change as local conditions change resulting in change of temperature
which fluctuates more, air temperature or water temperature?
air temperature generally fluctuates more than water
What keeps stability in the water?
Specific heat, the high capacity of water to absorb heat energy without changing temp. Latent heat of vaporization, the large amount of heat absorbed by water as it evaporates. latent heat of fusion, the heat energy that water gives up to its environment as it freezes
What is riparian vegetation?
the vegetation growing along rivers and streams which influences the temperature in streams by providing shade which insulates the stream environment
What are the two limits to thermal stability in aquatic environment temperature?
There will be affects of altered temperatures on the organisms living in the water, often of greater importance in aquatic systems is the effects that changes in temperature have on the amount of dissolved oxygen in water
Which holds more dissolved oxygen, cold water or hot?
Cold water hold more dissolved oxygen than warm water. So any increased temp in water not only poses a thermal stress but also induces oxygen limiting conditions. However deep water can also be depleted of oxygen during summer
What are zooplankton?
they are a diverse group of invertebrates living in the water column
Adapting to one set of environmental conditions generally reduces what?
Reduces fitness in other environments. If any organism can live and thrive in any environment they are said to have high fitness across all environment conditions. However these life forms do not exist.
What is the principle of allocation?
All organisms have access to limited energy supplies. Each individual organisms has a finite quantity of resources that it can use for all necessary life. (As a population adapts to a particular set of environmental conditions, its fitness in other environments is reduced)
What is law of toleration?
abundance and distribution of an animal can be determined by the deviation between the local conditions and the optimum site of conditions for a species
What is range of tolerance?
the entire range of conditions over which a species is able to survive in (good or bad)
do plants photosynthetic rates go up or down at lower temperatures?
Plants photosynthesize at a lower rate when the temperature is low
What is adaption?
involves a change in the gene pool of the population through differential reproductive successes of individuals
What is acclimation?
involves physiological, not genetic, changes in response to temperature, is generally reversable with changes in environment conditions
What are psychrophilic microbes?
Cold loving, marine bacteria that lives in the waters around Antarctica
What are Thermophilic microbes?
They can live at very high temperatures including hot springs
What are Hyperthermophiles microbes?
they are the most heat loving microbes. living in temperature optima above 80 C, some grow best at 110 C
How do organisms regulate body temperature?
by manipulating heat gain and loss.
What is metabolic heat (Hm)?
energy released within in an organism during cellular respiration. Always adds heat
What is conduction (Hdc)?
movement of heat between objects in physical contact. (Hot to cold always)
What is convection (Hcv)?
heat flow between a solid body and a moving fluid, such as wind or flowing water. (Hot to cold always)
What is radiation (Hr)?
Infrared part of the spectrum. this light is responsible for most of the warmth you feel from a light source
What is radioactive heat flux?
from you to the atmosphere is responsible for the chilling effect you feel standing outdoors on a cold windless day
What is evaporation (He)?
the loss of heat as water evaporates from a surface, always looses heat
what are poikilotherms?
have a body temperature that varies in response to changes in the external environment
What are homeotherms?
keep fairly constant internal temperatures
what are endotherms?
(includes humans) rely heavily on metabolic heat (Hm) to elevate internal temperature. They are usually homotherms
What are ectotherms?
they can control their body temperature through the use of external sources of energy manipulating predominantly (Hcd, Hcv, Hr, and He)
Animal burrows and microclimate
animal burrows or setts have their own microclimate
what is the regulating thing for body temp?
Hs = Hm+-Hcd+-Hcv+-Hr-He
what are the two options arctic and alpines plants have?
- increase their rate of radiative heat Hr or 2. decrease their rate of convective cooling
What is cushion growth form?
they close to the ground to provide shelter from the wind, the compact growth forms of cushion plant reduces the surface area to volume ratio , slowly moving air through the plant
what options do plants growing in the heat have?
Decreasing by conduction, increasing rates of convection cooling, reducing rates of radiative heating, Light coloured leaves,
how do some animals thermoregulate?
They change their colour, darker in the winter to absorb more heat, and the opposite for summer
What is the thermal neutral zone?
The range of temperature over which the metabolic rate of homeothermic animals does not change (the area in which the organism can adjust its self quite easily)
what are countercurrent heat exchanges?
They are vascular structures that reduce the rate of heat loss to the surrounding aquatic environment
