129 notecards = 33 pages (4 cards per page)
the scientific study of the interactions between organisms and their environments.
How are the interactions that ecologists study organized?
Into different levels of biological hierarchy (global, landscape, ecosystem, community, population, and organismal.)
Define BIOSOHERE and GLOBAL ECOLOGY
Biosphere- the global ecosystem
Define LANDSCAPE and LANDSCAPE ECOLOGY
Landscape - mosaic of connected ecosystems
Define ECOSYSTEM and ECOSYSTEM ECOLOGY
Ecosystem - community of organisms in an area and the physical factors with which those organisms interact
Define COMMUNITY and COMMUNITY ECOLOGY
Community- group of populations of different species in an area
Define POPULATION and POPULATION ECOLOGY
Population - group of individuals of the same species living in an area
Define ORGANISMAL ECOLOGY
Concerned with how an organisms structure, philosophy, and behavior meet the challenges posed by its environment
What causes latitudinal variation on the earth?
The earths curved shape causes the tropics (regions between 23.5N and 23.5S) most directly. Higher latitudes mean the sunlight strikes the earth and an oblique angle and light energy is more diffuse on earths surface.
Explain the global air circulation
High temps in the tropics evaporate water and cause warm, wet air masses to rise and flow tower the poles. They cool and create abundant precipitation in tropical regions. The then dry air masses descend toward earth and absorb moisture, creating an arid climate among the deserts. Some of the air flows toward the poles and air masses again rise and release precipitation around 60N and 60S. The cold dry rising air flows back to the poles and then back to the equator, absorbing moisture and creating a cold climate in the polar regions.
Describe the earth's wind patterns.
air flowing close to the surface creates predictable global wind patterns; land near the equator moves faster than the poles and deflects winds, creating easterly and westerly wind flow. Cooling trade winds blow from east to west in tropics, and prevailing westerlies blow from west to east in temperate zones.
What do ecologists do?
observe nature, generate hypotheses, manipulate environmental variables, and observe outcomes.
the long term prevailing weather conditions in a given area. the four components of climate are temperature, precipitation, sunlight, and wind.
What is the most significant influence on the distribution of organisms on land and in the oceans?
Define MACROCLIMATE and MICROCLIMATE
Macroclimate - patterns on the global, regional, and landscape level.
What are global climate patterns largely determined by?
the input of solar energy and Earth's movement in space (sun warms the earth and establishes temp variation, air and water movement cycles, and evaporation of water that lead to latitudinal variations)
How does the earth's annual passage around the sun affect climates?
It causes strong seasonal cycles in middle to high latitudes, effects day length, solar radiation, and temperature.
What do seasonal changes in wind patterns do to ocean currents?
they alter ocean currents and cause the upwelling of cold water from deep ocean layers. This water stimulates the growth of surface-welling phytoplankton and the organisms that fee on them. These upwelling zones make up a small percent of the ocean but are responsible for more than a quarter of fish caught globally.
Explain why the Pacific coast has a coniferous rain forest ecosystem and a large redwood grove, and why the west coast of northern Europe has a mild climate.
Cool misty climate from the cold California Current flows south along wester North America, supporting the rain forest and large redwood groves, and the Gulf Stream carries warm water from the equator to the North Atlantic, warming Europe.
In most areas, how do oceans and large lakes moderate the climate of local land?
When the land is warmer than the water, air over the land heats and rises, drawing a cool breeze from the water. When temperature drops more quickly over land than water at night, air over the warm water rises and draws school air from the land back over the water and replaces it with warm air from offshore.
Define MEDITERRANEAN CLIMATE
In some areas (S California and SW Australia), cool ocean breezes in summer war when the contact the land, absorb moisture, and create a hot aired climate rather than cooling the land with the breeze.
How do mountains influence air flow over land?
When warm moist air approaches the mountain, the air rises and cools, releasing moisture on the windward side of the peak. On the leeward size, cool dry air descends, absorbing moisture and creating a "rain shadow" (often determines where deserts are found). Mountains also affect the amount of sunlight reaching an area, and therefor the local temp and rainfall.
Do south-facing sloper int eh Northern Hemisphere receive ore or less sunlight than north-facing slopes?
South-facing slopes receive more sunlight and are therefore warmer and drier.
How do features of the environment (abiotic features) influence microclimate?
by casting shade, altering evaporation from soil, or changing wind patterns. Open land typically experiences greater temp extremes because of greater solar radiation and wind currents. These abiotic features influence the distribution and abundance of organisms.
Define ABIOTIC and BIOTIC
Abiotic - non living factors
Any large-scale change in Earth's climate profoundly affects the _____
What is one way to predict the possible effects of future climate change?
Look at the changes in temperate regions since the last ice age. As the climate warmed, glaciers retreated, and tree distributions expanded northward. We can make predictions about how distributions will change with continued climate warming.
Why is it a concern if plants will be able to keep up with the rapid warming of the earth?
we don't know if seeds can disperse quickly enough as climate changes. Fossil pollen shows us that in the past some species with winged seeds dispersed relatively far from a tree and expanded rapidly after the ice age. Others with seeds that lack wings were delayed for thousands of years. Some plants may have smaller ranges or eventually become extinct (such as the American beech plant).
Changes in the distributions of species are proof of what?
the world warming up - organisms have shifted their ranges farther North.
major life zones characterized by vegetation type in terrestrial biomes or by the physical environment in aquatic biomes.
Why is climate a major factor in determining the locations of terrestrial biomes?
Because climate has a strong influence on the distribution of plant species
a plot of the annual mean temperature and precipitation in a particular region. Based on annular averages.
Can 2 areas with similar averages of temperature and precipitation have different climates?
Yes, climographs are based on annual averages, but the pattern of climatic variation causes areas to have different climates because some areas may receive regular precipitation throughout the year while others have distinct wet and dry seasons.
What are terrestrial biomes named for?
Their major physical or climatic features and their predominant vegetation. Biomes are also characterized by microorganisms, fungi, and animals adapted to the environments.
area of intergradation, the transition from one biome to the next
What are the layers of vegetation that many forests have?
From top to bottom; the upper canopy, the low-tree layer, the shrub understory, the ground lyre of herbaceous plants, the forest floor (little layer), and the root layer. Non-forest biomes have similar layers though less pronounced.
Why do some biomes have layers?
Layering of vegetation provides different habitats for animals.
Does the species composition of each kind of biome vary?
yes. (Ex: in the northern coniferous forest of North America, red spruce is common in the east but does not occur in most other areas, where black spruce and white spruce are abundant)
an event such as a storm, fire, or human activity that changes a community, removing organisms from it and altering resource availability. Disturbance is more common than stability in biomes.
Why are biomes often "patchy", containing several different communities in a single area?
This is a result of disturbances in the biome.
Natural wildfires being an integral component of grasslands, savannas, chaparral, and coniferous forests is an example of what?
the fact that many biomes have plants that depend on periodic disturbance.
Describe TROPICAL FORESTS
They occur in equatorial and subequatorial regions, rainfall is relatively constant in tropical rain forests and highly seasonal in tropical dry forests, a high temp year round of 25-29C, vertically layered and intense competition for light, home to 5-30million species of insect, spiders, and other arthropods, most animal diversity of any terrestrial biome, rapid population growth of humans has lead to agriculture and development and is destroying many tropical forests.
Describe the DESERT
Occur in bands near 30N and 30S or at latitudes in the interior of continents, low precipitation and highly variable, temperature varies seasonally and daily, anywhere from -30 to 50C, low widely scattered vegetation, mostly bare ground, succulents such as cacti, deeply rooted shrubs, and herbs during infrequent moist periods, plants with reduced leaf surface area, water storage, and physical defenses such as toxins or spines, many nocturnal species, others such as snakes, lizards, scorpions, etc, animals with water conservation as an adaptation that can gt water by breaking down carbohydrates in seeds, many humans taken over exerts due to deep groundwater wells.
Describe TERRESTRIAL BIOMES
equatorial and subequatorial regions, seasonal rainfall with 8-9 month dry season, the savanna is warm year round, more seasonal variation that tropical forests, scattered trees with small leaves to adapt to dry conditions, fires are common, grasses, forbs grow rapidly after seasonal rains, large plant eating mammals such as zebras, predators such as lions, dominant herbivores are insects and termites, grazing mammals during droughts, earliest humans lived in savannas, cattle ranching and overhunting have led to declines in large-mammal populations.
midlatitude coastal regions, many names; chaparral in N America, matorral in Spain and Chile, garage and maquis in S France, and fynbos in S Africa. Seasonal precipitation, rainy winters, dry summers, cool fall/winter/spring (10-12C), 30-40C in summer, shrubs and small trees, greases, herbs, high plant diversity, many plants confined to small area, touch evergreen leaves to reduce water loss, adaptations to fire, browsers such as deer and goats, small mammals, amphibians, birds, reptiles, insects, heavily settled and reduced through conversion to agriculture and urbanization, humans contribute to fires.
Describe TEMPERATE GRASSLAND
veldts of S Africa, puszta of Hungary, pampas of Argentina and Uruguay, steppes of Russioa, plains and prairies of central N America, seasonal precipitation, dry winters, wet summers, periodic drought, -10C in winter, 30C in summer, grasses, forbs from a few cm to 2m in tall grass prairies, adaptations for periodic droughts and fire, grasses ca sprout quickly after fire, large grazers such as bison, burrowingg mammals such as prairie dogs, ideal for agriculture and growing grain, most has been converted to farmland.
Describe NORTHERN CONIFEROUS FORESTS
broad band across northern N America and Eurasia to the edge of the arctic tundra, "taiga", largest terrestrial biome, periodic droughts, gnerally 30-70cm of rain a year, some Pacific NW are temperate rain forests that receive over 300cm of rain, cold winters (-50C), hot summers (20C), cone-bearing trees such as pine and spruce, needle-like and scale-like leaves reduce water loss, migratory birds, mammals such as moose, brown bears, etc, diverse mammals, periodic outbreaks of insects that kill lots of trees, northern coniferous forests logged at an alarming rate, old-growth stands of trees may soon disappear.
Describe TERRESTRIAL BIOMES
midlatitudes in N Hemisphere, smaller areas in Chile, S Africa, Australia, and New Zealand, 70-over 200cm annually, significant rain during all seasons, 0C winters, 35C humid summers, vertical layers, epiphytes, deciduous trees, evergreen eucalyptus trees in Australia, hibernating animals, migrating birds, insects, heavily settled by humans, logging and land clearing for agriculture and urban development, though the forests are returning over much of their former range.
expansive areas of the arctic, 20% of earth's surface, high winds, low temp, alpine tundra plant communities, 20-60cm annually in arctic tundra by over 100cm in alpine tundra, -30C winters, less than 10C summers, herbaceous vegetation, mosses, grasses, forbs, permanently frozen layer of soil called permafrost restricts the growth of plant roots, large grazing musk oxen, caribous and reindeer are migrators, predators such as bears and foxes, bir species migrate, sparsely settle by humans but is the focus of mineral and oil extraction in recent years.
How are aquatic biomes characterized?
By their physical environment
How do ecologists distinguish between freshwater and marine biomes?
on the basis of physical and chemical differences. Marine biomes have salt concentrations that average 3% and freshwater biomes have less than .1%
Do aquatic biomes have more or less latitudinal variation than terrestrial biomes?
Why do the oceans impact the biosphere so greatly?
They make up the largest marine biomes, cover about 75% of the earth's surface, and water evaporated from oceans provides most rainfall. Ocean temp has major effect on global climate and wind patterns, marine algae and photosynthetic bacteria also supply a lot of the world's oxygen and come lots of carbon dioxide.
What are freshwater biomes closely linked to?
soils and biotic components of the surrounding territorial biome
Define PHOTIC ZONE, APHOTIC ZONE, PELAGIC ZONE, ABYSSSAL ZONE, and BENTHIC ZONE
Photic- sufficient light for photosynthesis
Define BENTHOS and DETRITUS
Benthos - ive in benthic zone, eat dead organic matter called detritus, which "rains" down from the productive surface waters of the photic zone.
Sunlight warms surface waters but the deeper water remain cold, thermocline separates these two layers
Semiannual mixing of waters in lakes as a result of changing temperatures is a turnover. It sends oxygenated water from the surface to the bottom and brings nutrient-rich water from the bottom to the surface in spring and autumn.
How are communities distributed in freshwater and marine environments?
distributed according to water depth, degree of light penetration, distance from shore, and whether they are found in open water or near the bottom.
Species distributions are a consequence of _____ and ______
ecological and evolutionary actions through time. Survival and reproduction of individuals that lead to evolution occur in ecological time and organisms adapt to their environment over the time fare of many generations in evolutionary time.
Define ECOLOGICAL TIME and EVOLUTIONARY TIME
Ecological - minute-to-minute time frame of of interactions between organisms and the environment
range from ponds a few square meters to lakes covering thousands of square kilometers, light decreases with depth, temperate lakes have seasonal thermocline, tropical lowland lakes have a thermocline year-round, oliogotrophic lakes and nutrient-poor and oxygen-rich, eutrophic lakes are nutrient-rich and depleted of oxygen in the deepest zone in summer and in winter if covered iwht ice,periodic oxygen depletion, oligotrophic lakes have less surface area relative to depth than eutrophic lakes, rooted and floating plants in littoral zone (shallow waters close to shore), phytoplankton in limnetic zone (further from shore), zooplankton (small drifting heterotrophs) graze on phytoplankton, fish in all zones, runoff from fertilized land.
inundated by water at least some of the time, supports plants adapted to water-saturated soil, low in dissolved oxygen, high capacity to filter dissolved nutrients and chemical pollutants, Basin wetland in shallow basins, riverine wetlands in shallow and periodically flooded banks of revers, fringe wetlands along coasts of large lakes and seas and include both freshwater and marine biomes, oat productive biomes on earth, water-saturated soils favor the growth of plants, invertebrates, birds, herbivores such as crustaceans, carnivores such as otters and dragonflies, help purify water and reduce peak flooding, draining and filling have destroyed 90% of wetlands.
Describe STREAMS AND RIVERS
high speed and volume of their flow, generally cold and swift, generally warmer where tributaries have joined, salt and nutrient content increases from headwaters to the mouth, headwaters rich in oxygen, narrow, rocky bottom, alternate depth, downstream stretches are generally wide and meandering, phytoplankton and rooted aquatic plants in areas that flow through grasslands and deserts, variety of fish, organic matter from terrestrial vegetation is primary source of food in temperate and tropical forests, agricultural and industrial pollution degrade water quality and kill organisms, damming and flood control impair natural functioning of ecosystem and threaten migratory species such as salmon.
transition area between river and sea, flows up estuary channel during rising tide and back down during falling tide, salinity varies with rise and fall of tides, among most productive biomes due to nutrients, complex network of tidal channels, islands, natural levees, mudflats, salt marsh grasses and algae, phytoplankton, worms, oysters, crabs, many fish, filling and pollution from upstream have disrupted estuaries.
Describe INTERTIDAL ZONES
periodically submerged and exposed by tides, twice daily on most marine shores, oxygen and nutrient levels generally high, high diversity and biomass of marine algae in rocky intertidal zones, vigorous wave action lack plants and algae in sandy intertidal zones, rich beds of seagrass and algae in sandy intertidal zones in protected bays or lagoons
Describe OCEAN PELAGIC ZONES
vast realm of open blue water, constantly mixed by wind drive oceanic currents, photic zones extends to greater depths than in coastal marine waters, high oxygen levels, low nutrient concentrations, 70% earth's surface, average depth of 4000m, deepest point more than 10000m, phytoplankton that account for half of the photosynthetic activity on earth, zooplankton, free-swimming animals such as turtles, fish, marine mammals, overfishing has depleted fish stocks in earth's oceans, polluted by waste dumping
Describe CORAL REEFS
formed largely from calcium carbonate skeletons of corals, reef-building corals live in photic zone, tropical marine environments, high oxygen keels, high fresh water an nutrients levels, begins as fringing reef on young island, forms offshore barrier reef later, and a coral atoll as the older island submerges, unicellular algae, mostly corals as animals, some fish and invertebrate (high diversity), collecting of coral skeletons and overfishing have reduced populations of corals and reef fishes, global warming contributes to coral death
Describe MARINE BENTHIC ZONES
consists of seafloor below surface waters of the coastal (neurotic) zone and the offshore pelagic zone, water temp declines with depth, continuous cold (3C) and high water pressure, oxygen at sufficient concentrations, soft sediments, photosynthetic organisms, unique assemblages of organisms near deep-sea hydrothermal vents on mid-ocean ridges, numbers invertebrates and fish, overfishing has decimated benthic fish populations, dumping organic wastes created oxygen-deprived benthic areas.
What factors effect the distribution if a species?
Biotic and abiotic factors
A Saguaro cacti not being able to live somewhere due to the low temperature is an example of what kind or factor?
Mice that eat seedlings, preventing the saguaro cacti from growing, are an example of what kind of factor?
the movement of individuals or gametes away from their area of origin or from centers of high population density. Contributes to the global distribution of organisms
In rare cases, long distance dispersal can lead to what?
Adaptive radiation, the rapid evolution of an ancestral species into new species that fill many ecological niches.
What do ecologists use to better understand the role of dispersal in limiting the distribution of species?
Experimental methods, because opportunities to observe dispersal directly are so rare.
When is the importance of dispersal most evident?
When organisms reach an area where they did not exist previously
What must happen for a transplant of a species to be successful? If it's successful, what does this tell us?
The species must survive in the new area and reproduce there sustainably. If it is successful then we know that the potential range of the species is larger than the actual range. (Could live in areas where it currently does not)
Why do ecologists rarely move species to new geographic regions?
This can often disrupt the communities and ecosystems to which they have been introduced. Instead ecologists document the outcome when a species has bee transplanted for other purposes.
How does habitat selection behavior effect an organisms distribution?
When individuals avoid a certain habitat that is suitable, their distribution is limited because their actual range is smaller than their potential range.
How do other species limit the distribution of another species?
Negative interactions with predators that eat animals or herbivores that eat plants can prevent certain organisms from living in certain areas. Other aspects, such as the presence or absence of pollinators, food resources, parasites, pathogens, and competing organisms, can also act as a biotic limitation on species distribution.
How do abiotic factors limit species distribution?
Abiotic factors such a temperature, water, oxygen, salinity, sunlight, or soil can limit distribution. If the physical conditions at a site do not allow a species to survive and reproduce, then the species will not be found there. Organisms can avoid ozone of these stressful conditions temporarily through behaviors such as dormancy or hibernation.
Why is environmental temperature an important factor in the distribution of organisms?
Temperature effects biological processes. Cells may rupture if the water they contain freezes, and the proteins of most organisms denature at temperatures above 45C. Most organisms function best within a specific range of environmental temperature.
Why is water availability an important factor in the distribution of organisms?
Species living at the seashore or in tidal wetlands can dedicate (dry out) as the tide recedes. Terrestrial organisms face a threat of dedication, and the distribution of terrestrial organisms reflects their ability to obtain minded conserve water. Water also affects oxygen availability in aquatic environments and in flooded soils, where the slow diffusion of oxygen in water can limit cellular respiration and other physiological processes. Flooded areas may have low oxygen content, but the surface waters of streams and rivers tend to be well oxygenated because of rapid exchange of gasses with the atmosphere.
Why does salinity affect the distribution of organisms?
Salt concentration affects the water balance of organisms through osmosis. Most aquatic organisms are restricted to either freshwater or saltwater habitat.
What is one aquatic organism that has the ability to go between freshwater and saltwater? How?
The salmon migrates between freshwater streams and the ocean, they use behavioral and physiological mechanisms to osmoregulate. They balance their salt content by adjusting the amount of water they drink and by switching their gills from taking up salt in fresh water to excreting salt in the ocean.
Why does sunlight affect the distribution of organisms?
Sunlight provides the energy that drives most ecosystems, too little sunlight can limit the distribution of photosynthetic species. Too much light can limit the survival of some organisms, high light levels an increase temperature stress if the animals and plants are unable to avoid the light or unable to cool themselves through evaporation. Trees are prevented from surviving in above certain elevations because the sun's rays are more likely to damage DNA and proteins due to the thinner atmosphere that absorbs less UV radiation.
Why do rocks and soil affect the distribution of organisms?
the pH, mineral composition, and physical structure of rocks and soil limit the distribution of plats and thus of the aim ales that feed on them, contributing to the patchiness of terrestrial ecosystems. The pH of the soil can limit the distribution directly through extremely acidic or basic conditions, or indirectly by affecting the solubility of toxins and nutrients. In a river, the rocks and soil that make up the riverbed can affect water chemistry, which influences organisms.
*Which action influences the abiotic components of an organism's environment?
*Which aspects of a region's climate have the most impact on plants and animals?
*True or false? Weather is defined as the prevailing long-term atmospheric conditions in a particular region.
*Which of the following statements about Hadley cells is true?
*Which location on Earth receives the most solar radiation per unit area?
*What are rain shadows?
*Which desert is caused by a Hadley cell?
*Which of the biomes—tundra, coniferous forest, temperate broadleaf forest, temperate grassland, savanna, chaparral, desert, tropical rainforest—require periodic fires to maintain their existence?
*Which of the following examples of an ecological effect leading to an evolutionary effect is most correct?
*Which of the following levels of ecological organization is arranged in the correct sequence from most to least inclusive?
*Which of the following might be an investigation of microclimate?
*Which of the following choices includes all of the others in creating global terrestrial climates?
*Why is the climate drier on the leeward side of mountain ranges that are subjected to prevailing winds?
*Which statement describes how climate might change if Earth was 75% land and 25% water?
*Palm trees and subtropical plants are commonplace in Land's End, England, whose latitude is the equivalent of Labrador in coastal Canada where the local flora is subarctic. Which statement best explains why this apparent anomaly exists between North America and Europe?
*Deserts typically occur in a band around 30 degrees north and south latitude because
*The main reason polar regions are cooler than the equator is that
*Generalized global air circulation and precipitation patterns are caused by
*Coral reefs can be found on the southeast coast of the United States but not at similar latitudes on the southwest coast. Differences in which of the following most likely account for this?
*Which of the following can be said about light in aquatic environments?
*Which series is correctly layered from top to bottom in a tropical rain forest?
*What is the limiting factor for the growth of trees in the tundra?
*Which climograph shows the climate for location 2?
*Which zone produces the most global oxygen?
*Which marine zone has the lowest rates of primary productivity (photosynthesis)?
*What does the left y-axis show?
*What does the red graph line represent?
*In which of the following years did the incidence of cholera reach its lowest level?
*In which of the following years was the sea surface temperature more than 1ºC above the average temperature?
A, B, E
*Which of the following statements is supported by the data in the graph?
*Is this statement supported or not supported by the data on the graph?
*In which of the following terrestrial biome pairs are both parts dependent upon periodic burning?
*In which community would organisms most likely have adaptations enabling them to respond to different photoperiods?
*Which of the following statements best describes the effect of climate on biome distribution?
*The oceans affect the biosphere in all of the following ways except
*What does the red line on the graph represent?
*What do the blue bars on the graph represent?
*Which two months have the highest average temperature?
*What is the best description of the yearly temperature range shown by this graph?
*What is the best description of the pattern of precipitation shown by this graph?
*What is the best estimate of the total yearly precipitation in the region represented by this graph?
*What biome does this climatograph represent?