Eco Lecture 1 Flashcards
what do ecologists do?
describe the distribution and abundance of organisms to solve ecological problems
What are the 5 types of ecological problems?
a) conversation
b) environmental issues
c) wildlife and resource management
d) pest control
e) human health
group of populations of different species in an area that interact
a community
: a group of individuals of the same species living in an area
a population
sets of species and physical environment they are found in
ecosystem
sets of ecosystems that are connected
landscape
terrestrial treeless biome?
tundra
something sudden that comes in and kills individuals from a
population
disturbance
is fire a natural disturbance? why?
natural as humans have been on the earth for a very long time
what happens to grass after a disturbance?
grows back quicker
as long as continual disturbance (on occasion) to a savanna ecosystem, the savanna will have largely ______ dominated ecosystem
grass
terrestrial biome with evergreen trees with mostly needle shaped leaves
northern coniferous forest
terrestrial biome with broadly shaped leaves that drop off once a year; on the northern hemisphere
temperate broad leaf forest
terrestrial biome with broad leaves, evergreens, and that has a broad band across the equator?
tropical forest
what is the hypothesis on the pattern of different vegetation in terrestrial ?
the pattern is driven by climate
two most important aspects of climate?
temperature
precipitation
distribution of tropical forest
occurs in equational and sub equatorial regions
temp of tropical forest year round?
little seasonal change; hot
plants in tropical forest
vertically layers, competition for light is high
Trees grow above closed canopy, canopy trees, one or two layers of subcanopy trees and layers of shrubs/ herbs
precipitation of the tropical rain forest and the tropical dry forest?
tropical rain forest: rainfall is pretty constant;
Tropical dry forest: highly seasonal;
distribution of desert biome?
occur in bands 30 degrees north and south latitude or at other latitudes in the interior of continents
precipitation of desert biome?
low and highly variable
plants of desert biome?
dominated by low, widely scattered vegetation; the proportion of bare ground is similar to other terrestrial biomes. Plants are succulents like cacti, deeply rooted shrubs and herbs that grow during the rare moist periods.
human impact on desert biomes?
Long-distance water transport and deep groundwater wells have allowed humans to maintain substantial populations in deserts. Reduced biodiversity of some deserts are the result of human urbanization
savanna distribution?
equatorial and sub equatorial regions
savanna precipitation
seasonal rainfall low; dry season
plants of savanna?
Thorny, small leafed trees; common fires during dry season→ dominant plants have adapted to the fires and are tolerant for the dry season
distribution of temperate grasslands?
South Africa, Hungary, Argentina, Uruguay, Russia, plains and prairies of North America
precipitation of temperate grasslands?
highly seasonal (dry winter, wet summer);
temp of temperate grasslands?
cold winter; hot summer
desert biome temperature?
highly variable both seasonally and daily;
plants of temperate grasslands?
dominant plants are grasses and forbs vary in height from few centimeters to 2 meters; grasses can grow quickly after a drought or fire; grazing animals helps prevent woody shrubs and trees entering grasslands
distribution of northern coniferous forest?
broadband across northern NA and Eurasia to edge of arctic; largest terrestrial biome
precipitation of northern coniferous forest?
periodic droughts common; some in US pacific
temperature of northern coniferous forest?
cold winter; hot summer
plants of northern coniferous forest?
dominated by cone bearing trees (pine, spruce, fir, hemlock) some of these depend on fire to regenerate
distribution of temperate broad leaf forest?
mainly at mid latitudes in Northern hemisphere
precipitation of temperate broadleaf forest?
distributed somewhat evenly with summer rain and winter snow
temperatiure of temperate broadleaf forest
winter (0 degrees), summer (max temp 35 degrees) and hot and humid
plants of temperate broadleaf forest?
distinct vertical layers (closed canopy, one or two strata of understory trees, herb layer); Northern hemisphere → deciduous trees are dominant which shed leaves for winter; Australia→ evergreen eucalyptus trees are dominant
_________ plays a big role in the transition from forested to non-forested biomes?
precipitation
definition of
can or cannot get there is a potential limit to a species; maybe just didn’t get there and their home now is fine
barrier
time limit
dispersal/ movement
_________: something about habitat that prevents species from thriving
too cold?
too dry?
too salty (water organisms)?
abiotic factors
____:insufficient food resources?
predators?
disease?
biotic factors
what did the coyote range expansion have to do with?
wolves
grey wolf used to occupy most of ______
north america
if wolves and coyotes compete for the same resource who wins?
wolf
do wolves prefer grassland or woodland? coyotes?
wolves–> woodland
coyotes–> grasslands
what facilitated the expansion of the coyote?
the elimination of the wolf; biotic factors
of individuals per unit area
density
of individuals that belong to a population
abundance
looks at changes in abundance of a species
populatin dynamics
explain why deserts are not located at the equator despite them being the hottest biomes
hottest at the equator, air begins to warm here
air rises and cools
cool air doesn’t hold as much moisture and it rains, (rainforest band)
while the air rises more air comes in to replace it
→ circulation cell
-doesn’t rain, and it picks up moisture at surface before bringing it to the rainforests
what causes outbreak of desert locust?
fast population growth–> quick and large change in abundance
\_\_\_\_\_\_\_change depends on: birth death immigration (came into pop) emigration (left pop)
population growth, N
what specifies a closed population
no immigration or emmigration
what is “R”
difference between births and deaths in a population –> individuals added to a population
what is “r”
per capital rate of population growth
r is positive, population is ____
increasing
r is negative., population is ____
decreasing
specific open population characteristic?
there is a difference between immigration and emigration
the difference between immigration and emigration rates is called ____ represented by the variable __
net per capital migration rate, m
female locust egg laying explanation
the female locusts would sense the vegetation, feed, produce the eggs (more than usual) and lay eggs in soil around vegetation (good egg survival) then when the eggs hatch there is food for the young locusts (high young survival rate)
distribution of eggs of locusts are ___
clumped
is the density high in young hoppers?
no
population of solitary forms –> population of swarms
pale–> dark and sociable
gregarization
when do locusts solitary forms fly? gregarious forms?
night (one); day (many)
the main driver of gregarious changes
serotonin
explain why gregarious goes back to solitary forms in desert locusts?
rains ends → no new food
already have eaten all old food
no more crowing
not happy eatng together, resort back to solitary form
