Final Flashcards
1
Q
What are the five interspecific interactions?
A
Neutral Mutualism Commensalism Predation Competition
2
Q
Describe the “Neutral” type of interspecific interaction.
A
neither affected
3
Q
Describe the “Mutualism” type of interspecific interaction. Give examples
A
both benefited:
Coyotes and Badgers are known to sometimes help each other hunt for prairie dogs; the coyote can chase it and the badger can dig for it
Nitrogen fixing bacteria give nitrogen to soybeans, which function as a habitat
4
Q
Describe the “Commensalism” type of interspecific interaction.
A
one benefited, the other not affected
5
Q
Describe the “Predation” type of interspecific interaction. Include the types and definitions of parasitism.
A
one benefited, the other is detrimental:
Herbivory
Carnivory
Parasitism: one benefited, the other got harmed (e.g., tapeworm)
Parasitoidism: a type of parasitism, but the host eventually got killed
Endoparasitoidism: a parasite that lives inside its host
-Ex: Chinese caterpillar fungus
Cannibalism (eating its own species)
6
Q
Describe the “Competition” type of interspecific interaction.
A
mutually detrimental or hurt
7
Q
What are the possible consequences of interspecific competition?
A
Competitive exclusion or coexistence
8
Q
Define Allelopathy.
A
Effect of metabolic products of plants on the growth and development of other nearby plants.
9
Q
Give examples of plants that exhibit allelopathy. List the types of chemicals used.
A
Types of chemicals: acids, bases, phenolics, aromatic cpds
Broom sedge: inhibit shrubs
Bracken fern: phenolic acids to kill conifers
Black walnut: secrete precursor to juglone, works against broad leaf plants
Bamboos: secrete phytotoxins against ferns
10
Q
Define plant secondary compounds
A
Compounds not directly related to plant growth (Ex: phytotoxins of bamboos)
11
Q
Describe the phenomenon of invasive exotic species in the Great Lakes
A
(competition w/ endemic spp.)
139 exotic spp. introduced into Great Lakes ecosystems; invertebrates and vertebrates. Exotic spp. have caused 68% extinction of fish species and 70% of endangered spp. in North America.
12
Q
Why is difficult to find field examples of competitive exclusion or to conduct competitive exclusion experiments in the field?
A
Don’t know what stage they are at
Environment changes
Immigration & emigration
Genetic alterations (mutations, recombinations, etc)
Carrying capacity unknown
Life history unknown
Has already settled through co-evolution (most important)
13
Q
Describe Gause’s Principle (or competitive exclusion principle) and its 3 assumptions
A
When two or more species coexist using the same resource, one must displace or exclude the other. In other words, complete competitors cannot coexist.
-When the niche overlaps too much only two outcomes. One or more species may start to explore other niches
Assumptions of competitive exclusion:
1 Environmental factors remained constant
2 No emigration/immigration
3 Over time, competitors genetically unchanged
These are unreasonable assumptions
14
Q
What is the application of competitive exclusion principle in the reintroduction of an endangered species?
A
In most cases their niche has already been occupied, you must be cautious
15
Q
Describe the interaction of the chipmunks in Sierra Nevada
A
Co-existence of different species of chipmunk through the adoption of a unique niche. Some chipmunks (Least) can live in wide range, but have home ranges restriction by aggressive other species (Yellow-pine chipmunk). The limit is defined by the most aggressive species (lodgepole)
16
Q
Define character displacement
A
Shift in species’ morphology, behavior, or physiology as a result of natural selection resulting from interspecific competition
17
Q
Compare fundamental niche vs. realized niche
A
Fundamental niche: free from interference from other species
Realized niche: niche of a species when part of that niche has been subtracted by competition
18
Q
What is a guild? Give an example
A
A group of species utilizing a gradient of resources in a similar way. Ex: chipmunks in Sierra Nevada
19
Q
Describe the ecological significance of the relationship between grey wolves and coyotes
A
In the 1600s many wolves were killed so people could settle in New England. Example of fundamental niche vs realized niche in that the niche of the coyotes changed when relieved from the pressure of the wolves. Example of Interference competition in that both populations negatively effect each other when coexisting
20
Q
Describe the population dynamics of snowshoe hare and lynx
A
When the population of the snowshoe hare was high, the lynx population was also high; vice versa
Their predator-prey cycle was around ten years (would see a great peak in population of both the hare and the lynx at the same time every ten years)
21
Q
Describe the three hypothesis about the snowshoe hare vs lynx population dynamic and the evidence that supports them
A
(likely a combination of all three):
Simple Predation
Conventional predator-prey cycle
Simple food limitation
Survey food abundance over ~12 years, close relationship between drop in woody browse (winter food) and drop in snowshoe hares and lynxes
In canada, a food station was put out to manipulate food availability and test this hypothesis
Fluctuating secondary compound contents
Plants (especially in winter) will create secondary compounds that are toxic to hares and will mess with their digestive function -> reduce total energy -> less energy for reproduction
22
Q
Describe the predator-prey cycle
A
Prey population goes down as predation occurs -> less predators -> less predation -> prey population rises -> …
Clear patterns are not often seen
23
Q
Why aren’t clear examples of the predator-prey cycle often seen? (3 reasons)
A
The prey population is density-dependent (i.e., internal regulation).
Almost every species is attacked by more than one species of predators. Most predator species attack more than one species of prey.
Long-term monitoring data not exist
24
Q
What were the discussed types of defense chemicals?
A
Toads, snakes: peptides, alkaloids
-Destroy RBC, increase coagulation, neurotoxic
Stinkbug: volatile terpenes
25
What were the types of camouflage/Cryptic coloration discussed?
Flounder – match the background
Walking stick – resemble a twig
Year-old deer possess white skin spots to blend in with sunlight penetrating the forest
26
Describe the chemical defenses of the monarch butterfly and its relationship to blue jays
Monarch butterflies cause physiological issues in the blue jays (contractile force of the cardiac muscles), dissuading the blue jays from consuming them
27
What were the types of flashing coloration/shape discussed?
White-tailed deer flash their tail to warn other deer when they sense danger. The owl butterfly has fake eyes on its wings to dissuade predation, as predators normally go for the neck and the eyes of their prey, leaving the butterfly mostly intact.
28
Describe the two different types of mimicry: what are they? How do they work?
Batesian mimicry:
non-toxic resembling toxic
Mullerian mimicry: distasteful, mimic each other. The predators need to be exposed to only one coloration to recognize the signal
29
What are some behavioral defenses employed by prey species?
Redirect predators (mother bird distracting the predators by acting injured)
Scatter around (schools of small fish swim together, then scatter when a predator gets close so they don’t have time to choose a good prey
Form a concentrated formation (musk ox)
30
How do prey species affect the timing of their reproduction to protect against predators?
Reproduce in a very short period of time or shift timing of reproduction to avoid predators (If predators are active in day, you become active in the night; in hibernation try to avoid being present the same year their predators are active
Ex: Cicada
31
What are the outcomes of ingesting PSCs?
Behavioral deterrence- the animals do not want to consume the materials
Anti-biosis- reduction in growth rate, in development, stillbirth
32
Why do plants and animals evolve the same types of chemicals for defense?
These happen to be the most effective compounds
33
Define Cannibalism. In what species is it common? In what situations does it occur?
Killing and eating an individual of the same species.
Common in protozoans, rotifers, insects, frogs, fish (e.g., walleyes), birds, mammals including humans.
In what situations? Stressed populations, facing starvation
Walleyes in summer
Victims: young and small
34
Describe the difference between genotype vs phenotype
Genotype is the sum of hereditary information
| Phenotype is the external, observable expression of the genotype; morphological expression of genes
35
Define Phenotypic plasticity
The ability of an organism to change its phenotype in response to changes in the environment
36
What are the three outcomes of natural selection of a population? Describe them
Stabilizing Selection: Favors phenotypes near the population mean; occurs in stable environments; environmental pressure on two extremes; most common type found in stable environments
Directional Selection: Favors extreme phenotypes; occurs with an abiotic or biotic selecting force; environmental pressure only on one extreme; pushes population to other extreme (Darwins medium ground finch)
Disruptive Selection: Favors both extreme phenotypes; natural force acts on intermediate phenotypes and pushes them towards the extreme; results in a population of two or more genotypes/phenotypes; 2 selection pressures → 3 groups (Papilio dardanus butterfly)
37
Describe genetic polymorphism
Type of disruptive selection- A discontinuous genetic variation resulting in the occurrence of several different forms of types among the members of a single species.
38
Describe Industrial melanism
the prevalence of dark-colored varieties of animals (esp moths) in industrial areas where they are better camouflaged against predators than paler forms
Ex: moth living in industrial manchester England had only three phenotypes (black, gray, white) when before there was a range of colors, black also came to dominate with 95+% of the population, soot coated wood and killed lichens
39
What is inbreeding depression? What is outcrossing depression
Inbreeding depression: reduced genetic variability, decreased fertility, loss of vigor, reduced fitness, reduced pollen and seed fertility in plants, and even death.
Outbreeding/Outcrossing is when the species is mated with unrelated individuals. Could fail resulting in offspring from crossings that are not as well equipped in their environment
Ex: Northern bobwhites (Ohio, Illinois, Pennsylvania) were in trouble, so Southern bobwhites (Alabama) were introduced and they started breeding
Big failure -> offspring from crossings could not resist cold environment (due to southern parent) and had high mortality
40
Describe the Founder Effect. Give an example
Effect of starting a population in a new location with a small number of colonists, which contain only a small and often biased sample of genetic variations of the parent population; a markedly different new population may arise.
Ex: migration
41
Describe the Genetic Drift. Give an example
Over a period of time, BY PROBABILITY some genes in a population are fixed and other alleles are lost. i.e., drifted and fixed.
Rate of genetic drift is determined by the size of the population
Ex: Northern Elephant Seals had a very small level at one point, they now lack genetic diversity
42
Why are insects/beetles best to study adaptations?
Insects have a high number of species and variety of adaptations
43
Describe Charles Darwin
On The Origin of Species (1859)
traveled to a lot of continents, islands (either far or close and small or large). He observed animals who seemed to have not have changed in many years. He also observed animals that have changed a lot. He waited almost three decades to publish his results- his family (upper class) worried about the church of England. He told his friends though
44
Describe Alfred R. Wallace
Introduction of Species
Studied in Amazon River and far East. Wrote a letter to Darwin talking about evolution. Darwin was shocked that someone else had similar thoughts. Wallace’s book was very similar to Darwin’s.
45
Describe Charles Lyell
a lawyer and a geologist
Close friend of Darwin, romantic person, invited Wallace and Darwin to present their data at a conference.
46
Describe Thomas Henry Huxley
Comparative anatomist, very slow in accepting Darwin’s theories. Later he became one of his biggest champion.
47
Henry Walter Bates
The Naturalist on the River Amazons
Studied in Amazon river area and collected more than 14,000 species, including 8,000 new species. All were shipped back to the United Kingdom. He was the first person to describe batesian mimicry (non-toxic imitate toxic).
48
What are adaptations a product of?
Natural Selection, ultimate end is speciation
49
Define epigenetics
environmental factors that influence the degree of gene expression
50
Why does adaptation and evolution occur?
Reproduction in a population is not random; ABIOTIC and BIOTIC factors favor certain traits, so certain individuals are more successful in reproduction than others (i.e. selective outcome).
51
What are the two ways to characterize species by spatial relationships?
Sympatric species- (subpopulations occupy same area)
Allopatric species- (subpopulations separated geographically)
52
Define sympatric species
a species in which subpopulations occupy in the same area at the same time. Have opportunities to breed.
53
Define allopatric species
a species in which subpopulations were separated geographically.
Once they are separated long enough, no way to know whether they can mate.
54
How do you determine if separated subspecies are still the same species?
To determine if they are the same species, must bring them together → allow them to mate with each other and produce fertile offspring
55
What is a cline? Give an example
a measurable, gradual change in population characteristics over a range of geological region. Result from adaptation of a gradual change physiologically, behaviorally, and genetically in an ecological gradient (e.g., temp, moisture, light, nutrients, etc)
White-tailed deer: 136 kg to 46 kg, from north to south
-due to temperature change, this keeps you warm
-This occurs on other species as well where subpopulations are in different areas, to ensure a good surface area to volume area
(More volume:surface area ratio=warmer animals)
56
What is an ecotype?
genetic strains of subpopulations adapted to its unique local environmental conditions.
- Marked discontinuities, abrupt changes (i.e., punctuated)
- Also called step clines
57
What are geographical isolates? What is an example?
Population that is separated from exchanging genetic material with other organisms of the same species
Salamanders in southern Appalachian Mountains form several subspecies due to barriers of rivers and mountains
58
Describe the two mechanisms of speciation
1. Allopatric speciation (or geographic speciation):
The separation of a population into two or more evolutionary units (i.e., species) by some geographic barrier that causes reproductive isolation
2. Sympatric speciation (mainly behavioral speciation)
A new species may arise within a population occupying a single habitat or within the dispersal range of a population.
E.g., insects parasitic to plants
(Two major isolating mechanisms, Geographically,
Ethologically (i.e., courtship, mating behaviors))
59
What is adaptive radiation?
Evolution from a common ancestor to divergent forms adapted to distinct ways of life.
Ex: finches adapted to different food groups (cactus, insect, seed, fruit)
60
What is the definition of a community?
A group of interacting plant and animals living in a given area in the same period of time
61
Compare and define biomass and standing crop biomass
Biomass: weight of living materials
Unit: dry weight per unit area
How to measure? - harvest just above to ground
Standing crop biomass: Total amount of biomass per unit area in a given period of time
Unit: dry weight per unit area per year
62
What is the difference between an edge and an ecotone?
Edge: the place where two or more different vegetation communities meet.
Ecotone: the place where communities meet and intergrade.
63
What is the edge effect?
The variety and abundance of species are often more abundant in and around ecotones and edges
64
What is an ecological island?
An isolated habitat or area
Either by choice or geography (Bugs could choose to live only on one tree)
65
Describe the Shannon Index of Biodiversity. How do you calculate it?
A numerical representation of the diversity of a particular community that considers both evenness and richness. It is calculated by finding the proportion of each species, taking the natural logs of all the proportions, multiplying that by the proportion, summing the numbers, and multiplying that sum by -1. The bigger the number the better the diversity.
-1 * (P * Ln[P] for all species)
66
Describe the Coefficient of Community. How do you calculate it?
A numerical representation of the similarity of two communities that considers only richness. It is calculated by multiplying 2 by the number of species in common, over the sum of the number of species in each community. The bigger the number the higher the similarity.
2*(number in common) / (# in community 1 + # in community 2)
67
Describe Percent Similarity. How do you calculate it?
A numerical representation of the similarity of two communities that considers only evenness. It is calculated by summing the lower proportion of each species in common.
For example, if one community has 45% Oak and 55% Pine, and another has 30% Oak, 60% Pine, and 10% Popular, the Percent Similarity would be 30+55+0.
68
Describe the Island equilibrium theory. How would you use a figure to describe the theory and factors influencing the equilibrium?
The MacArthur-Wilson Island Equilibrium Theory says that the number of species of a given taxon established on an (ecological) island represents a dynamic equilibrium between the immigration rate of new colonizing species and the extinction rate of previously established colonizing species. Two factors are size of the island and distance from continent. Smaller islands will have more extinction, closer islands will have higher immigration rate. (The equilibrium number of species will remain fixed)
69
Why does the immigration rate continue to decline over time?
?- As the niches become occupied, new species cannot enter and extinction occurs less frequently
The removal of corridors
70
Describe how corridors work with ecological islands. What are the applications in conservation ecology?
If a habitat is fragmented, corridors should be created to connect as many fragments to each other at a time (ex: better to have a triangle of 3 rather than a line of 3)
- Applications in conservation ecology
If you can only pick a few fragments to save out of a large habitat, choose those to form the highest number of connections possible (a line would have right-center and center-right, while a triangle would have top-left, top-right, and left-right)
71
Define succession. What is the difference between primary and secondary succession?
Temporal variation in community structure at a given location.
Primary succession – occurs at a location that was not previously occupied by a community; a newly exposed surface
Secondary succession – occurs at a location that was previously occupied by a community and then underwent a disturbance that removed all or part of the existing community
Floods and wildfire
72
Differentiate between initial/early vs late successional species
Early/initial successional species are the initial colonists, or pioneer species. Often have:
high growth rates
smaller size
high degree of dispersal and colonization
high rates of per capita population growth
R-selected (in general)
Late successional species arrive later. Often have:
longer lifespans
larger size
lower rates of dispersal and colonization
lower rates of per capita population growth
K-selected (in general)
73
Define keystone species, give two examples on how they influence community structure
A species that has disproportionate influence over community structure and functions. Removal will negatively affect many other species, causing a great loss in diversity.
By providing habitat: The coral Oculina arbuscula provides a habitat for over 300 species of invertebrates, many of which complete most of their life cycle inside the coral.
By feeding behaviors: African elephants are destructive feeders that feed mainly on browse. They reduce tree and shrub density, favoring growth and reproduction of grasses.
74
Define Autogenic and Allogenic environmental change
Autogenic (i.e., self generated) environmental change:
the result of the presence and activities of organisms within the community
Allogenic environmental change:
Governed by physical, not biological process
e.g., temperature declines over elevation
75
How is diversity related to succession?
Diversity does not always increase but does change
76
Define a climax forest
a stable end forest that perpetuates itself under prevailing environmental conditions.
Need a fire to rejuvenate its ecological functions.
77
Describe fires in Chaparral California
Occurs every 20 years, before 1960s we though wildfires were bad. in the 60s-80s we start to realize their importance
78
Describe the fire in Yellowstone national park in 1988
9 months to take out fire, 36% of the area was affected
1st few weeks: people furious, this was our first national park
1st couple of months: we should let it burn
Main thing: Tried to learn about succession from this burning, forests are in general overprotected
79
Describe prescribed fires
To avoid large, spontaneous fires, there should be smaller, purposefully set forest fires about every 20 years or so. Fires are not bad for ecology, but are a necessary part of sucession.
80
Differentiate between ground and crown fires
A crown fire spreads quickly through the branches of a forest, while a ground fire burns everything and helps seeds grow and new life to spread.
81
Know about the large ice sheet that covered Canada and the occurrence of succession after it shrunk
The great ice sheet the Laurentian shrunk dramatically between 18 TYA and 8 TYA, during the Wisconsin Glaciation Stage
Four Genera Of Trees Started to take Over: Spruce, White Pine, Oak, and Maple
Their distribution determined by patterns of pollen deposition in sediment cores
Differences in expansion rate are the results of species response to temperature change
82
Watershed vs stream, what are the order of the streams of a watershed
A watershed is an area of land where all the water that drains off of it goes to a common outlet. Streams can make up a watershed, a 1st order stream is the smallest, the largest stream (that the other streams connect to) is the largest order
83
Differentiate between fast and slow streams. Define riffle zones. Describe the areas between riffle zones. Describe the type of animals found in fast flowing streams. Describe the 5 main factors that influence stream diversity
Riffle zones: Areas where water flows quickly and there is a high oxygen content and lots of life. They are the majors sites of primary production.
The slow flowing areas between riffle zones is where decomposition occurs, reducing CO2 to HCO3- which maintains the water’s stability
Fast flowing streams have streamlined animals
The diversity of streams depends on nutrients, temperature, light, depth, topography, and other factors
84
What are the four groups of stream invertebrates?
Shredders/Collectors: Process detrital materials (coarse and fine particulate organics)
Grazers: Feed on algae coating on stones
Gougers: Burrow into waterlogged trunks
85
Define Eutrophication
The nutrient enrichment of a body of water, excess of nitrogen and phosphorous
86
When did the Clean Water Act occur? What was its aim?
1972
To restore and maintain the chemical, physical, and biological integrity of the nation’s waters by preventing point and nonpoint pollution sources, providing assistance to publicly owned treatment works for the improvement of the wastewater treatment, and maintaining the integrity of wetlands
87
What is the NPDES?
National Pollutant Discharge and Elimination System (NPDES): A permit program for point source pollution
88
What is TMDL?
Total Maximum Daily Load (TMDL): A value of the maximum amount of a pollutant that a body of water can receive while still meeting water quality standards
89
Describe DO
Dissolved Oxygen (DO): The amount of dissolved oxygen in a river or stream, < .5 mg/L anoxic, .5-2 hypoxic, <3 stressful, >5 healthy
90
Describe BOD and BOD5
Biochemical Oxygen Demand: The amount of dissolved oxygen needed by aerobic microbes to break down organic material present in a given water sample at a certain temperature over a specific time period.
5-Day Test (BOD5): Measure the change in oxygen content in a water sample
91
Differentiate between point source and nonpoint source pollution
Point: Comes from a single, identifiable source or point. Effects usually remain local, Examples include sewage pipes, smokestacks, and oil spills.
Nonpoint: Source that cannot be traced back to a single thing, more diffuse and non concentrated around a particular point or source. Examples include CO2 in atmosphere
92
Describe the nitrogen cycle
The process of nitrogen transformation including N2 in the air, N in organic matter, and NH4+/NO3- in soil and water
93
Define ammonification
The transformation of organic N into NH4+ in the soil or water
94
Define nitrification
The oxidation of NH4+ in the soil or water to NO2-, then to NO3- in the soil or water by bacteria of the genus nitrosomona or nitrobacter
95
Define denitrification
The reduction of NO3- in the soil to N2 in the air by anaerobic bacteria
96
Define nitrogen-fixation
The process of converting N2 in the air to organic N, usually by lightning
97
Define the phosphorous cycle
The process of phosphorous transformation including P in organic matter and PO4-3 in rock or natural phosphate deposits
98
Define mineralization related to phosphorous
The process of P from dead organic matter becoming phosphate in rock or in deposits
99
Tell me about plasticizers. Talk about where they are found, how they are introduced into the environment, and their effects.
Plasticizers are common in both southern and northern MO streams. They come from air transportation via rain. Many of them have estrogen-like properties. For example, in the 1990s people in the UK found fish with bisexual organs such as ovotestes.
100
What are fish enclosures for? How much control do researchers have?
Fish enclosures are used so that researchers can connect a particular location with the effects of a compounds. They prevent fish from moving up and down streams and can test the development of individuals under real-world conditions.
101
Describe a mesocosm study
In a mesocosm study, tubs filled with stream water are connected to the stream and filled with plants and animals so that researchers can study their interactions. There is more control in the mesocosm than the enclosure studies. They allow testing of the community effect of interactions under stressful conditions.
102
Describe a microcosm study
In a microcosm study, water is brought to the lab and placed in tanks with algae, plants, and lab surrogate animals. Amphibians are good cause they feel the effects of changes in both habitats. There is even more control, and scientists are able to change one condition at a time (such as the dilution of stream water). These can find dose-response conditions and threshold effects.
103
How would you conduct a comprehensive stream ecosystem assessment?
Do everything we talked about before this. Make measurements of biodiversity, similarity to other ecosystems, test the stream for things like turbidity and BOD, check nitrogen and phosphorous levels, and do an enclosure/mesocosm/microcosm experiment.
104
How are ecosystems classified (terrestrial vs aquatic)
Terrestrial is classified by vegetation, aquatic ecosystems are classified by salinity
105
How are lakes and ponds formed? (3)
Glacial depression
Shifts in Earth's crust forming depressed areas
Dams (beaver or man-made)
106
What are the three factors that influence the distribution and diversity of life in lakes and ponds?
Temp, O2, light
107
Define Thermocline
a layer in a thermally stratified body of water in which temperature changes rapidly relative to the remainder of the body
108
What is the significance of the hydrological cycle?
Freshwater, saltwater, and terrestrial ecosystems are not independent
109
Describe the summer layer of epilimnion in lakes/ponds
Warm, oxygen-rich upper layer of water
110
Describe the summer layer of Metalimnion in lakes/ponds
Zone with a significant drop in temperature
111
Describe the summer layer of Hypolimnion in lakes/ponds
Cold, oxygen-poor layer of water with no plants and no light
112
Define overturn
A transition of oxygen and temperature from a heterogeneous distribution to a homogeneous distribution throughout a lake/pond in late fall and early spring
113
What is stratification of a lake? When does it happen? Why? Effect on O2, nutrient and fish distribution?
The stratification of a lake is the arrangement of its water into distinct layers. In the summer, the lake is stratified into the epilimnion (warm, O2 rich), metalimnion (thermocline, significant drop in temperature), and hypolimnion (cold, O2 poor). Only a small amount of water is in contact with the air, and respiration of O2 by decomposers at the bottom of the lake consumes a lot of O2.
114
Distinguish the differences among oligotrophic, eutrophic, and hypertrophic lakes
Oligotrophic- Nutrient-poor, Conifers nearby
Mesotrophic- Moderate nutrient-rich
Eutrophic- Very nutrient-rich, Deciduous and Farmland trees nearby
Hypertrophic- Extremely high levels of nutrients, our fault
115
Describe how overturn occurs in late fall
Cold, dense water sinks from the surface until the temperature becomes uniform. Nutrients and O2 are evenly distributed.
116
Describe how overturn occurs in early spring
Top layer is still colder relative to lower levels (due to sheltering from wind), so newly synthesized nutrients sink and O2 at the top layer mixes with other layers
117
What are the two ways of dealing with hypertrophic lakes/ponds? Describe them
Use CaCl2 or CaSO4 to kill plants
Does not remove nutrients
You can also remove algae and plants
Better, will take years to take effect
118
How do you study lake nutrient decomposition?
Do a litterbag study. Put a bunch of organic litter in a bag in the riverbank and monitor the amount left over a month.
119
Describe the geographical distribution of lakes with different nutrient levels
Ozark Highlands, Ozark Border, Glacial Plains, Osage Plains
All of the oligotrophic lakes in MO are in the Ozark Highlands.
The mesotrophic lakes are in the Ozark Highlands (49%), and in the Glacial Plains (29%).
Eutrophic lakes have a similar distribution in the Glacial Plains (47%) and the Osage Plains (29%).
Hypertrophic lakes are split amongst the Glacial Plains and the Osage Plains.
120
What is the correlation between nutrient levels and forest coverage.
The amount of nutrients (both N and P) increases in streams that are surrounded by more cropland and less forest.
121
What are the two measures used to classify trophic state of a lake or a pond?
Trophic level can be determined by the amount of phosphorous, or by the ratio of nitrogen to phosphorus.
low phosphorus in oligotrophic, so high nitrogen to phosphorus ratio, high phosphorus in eutrophic, so low nitrogen to phosphorous ratio
Phosphorus is limiting factor in land water
122
Know this:
One of the major human-caused pollutants is nitrogen and phosphorous. This can lead to eutrophication, which enhances primary productivity. However, the exceedly high levels of net primary productivity can lead to anoxia and the development of dead zones.
Net primary productivity increases among phytoplankton and other aquatic autotrophs. When they begin to die, they sink to the bottom of the coastal water where they provide food for bacteria. The resulting increase in respiration decreases dissolved oxygen in the water. This begins in the bottom (benthic) zone, and is limited by the thermocline. When winds move away the surface water, it is replaced by the oxygen-depleted deeper water. This means that there is no oxygen in any layer of the water, which can cause aquatic life to move towards the shoreline and/or die.
Dead zones can be found worldwide, including lakes such as Lake Erie. The largest dead zone is the hypoxic Gulf of Mexico. It is caused by eutrophication from the Mississippi River, which drains much of the United States, including farmland. The anoxic zone of the Gulf of Mexico develops each spring as rains wash away chemical fertilizers from farms. The dead zone is causing long-term changes in species diversity and the structure of food webs, and frequently causes massive fish kills.
We need to manage nutrients more efficiently in farm field by using fewer fertilizers and timing applications to limit runoff of excess nutrients. The restoration of wetlands and riparian (river) zones can also help capture nutrients.
-
123
What are the differences in vegetation between marshes and swamps?
Marshes will have tall grass but no shrubs or trees. A swamp is a forested wetland and will have both shrubs and tall trees.
124
Are marshes located in higher latitude than swamps?
Yes
Do not think this is correct in his view->
Salt or tidal marshes occur in temperate (near equator) latitudes where coastlines are protected from the action of waves within estuaries, deltas, and by barrier islands and dunes. Swamps are more northern?
125
Describe the unique function of mangroves
Mangroves serve as natural wave breakers that can protect against waves and tsunamis without needing to be maintained or replaced.
126
The name of special roots that help trees take in O2 in mangroves.
Pneumatophores are special root extensions used to increase oxygen intake.
127
How do fiddler crabs get their name? What are the functions of their
enlarged front claw?
Fiddlers are named because when they wave their oversize claw to attract mates, it appears like they are playing a fiddle.
128
What are Mudskippers (fish? Amphibians?)
Mudskippers are fish that can breathe, have eyes high on their heads, and have arm-like fins
129
What is viviparity?
Giving live birth. This can apply to plants as well as animals. This can happen when new plants arise from buds or seedlings that have formed or germinated while still on the parent plant, and are dropped when ready to establish themselves in the substrate.
130
Why was the preservation of the mangrove mentioned in the classroom a
huge success?
Restoration of the mangrove area was advertised as a way to boost tourism, both for ecotourism and for things like proposals and birdwatching. The scientists behind the restoration collected a bunch of scientific information, and educated government officials about the possible long-term ecological and economic growth. They got fishermen to support their plant, took K-12 kids on field trips to the area, and got support from citizens and NGOs. Restoration was easier due to continuous research funding and education programs. They also got sponsorships from private industries (good advertising for the companies).
131
Characteristics of peatlands
Peatlands, or mires, are wetlands that contain a considerable amount of partially decayed organic matter. They are found in coastal regions and mountain regions. Their distinguishing feature is that the water table is close to the soil surface, creating anaerobic conditions, leading to slow microbial activity. This means that the production of organic matter is much faster than the rate of decomposition.
132
The differences between a fen vs. a bog (both types of peatlands)
Which has sedges and which has sphagnum?
For fens, the source of water is groundwater, and they have plants like sedges. The water in bogs comes from precipitation, and their major plant is sphagnum.
The main difference between a fen and a bog is that fens have greater water exchange and are less acidic, so their soil and water are richer in nutrients
133
Constructed Wetlands – functions?
Water in constructed wetlands is for wastewater processing. The contaminated wastewater goes through three times and then discharge the water into adjacent rivers or basins. This is regulated by clean water act (point source pollution). Colombia has four spaces over 1.8 miles to remove heavy metals. You can harvest the plants in the wetland and compost/incinerate them.
134
What are the functions and values of wetlands?
They provide surplus energy outflows to support adjacent ecosystems, they play a role in decontamination, and they provide habitat for waterfowl.
135
Loss of wetlands and migratory bird flyways
We have gone from 160 million hectares to less than 100 million, most of which are contaminated. This messes with birds, cause they like to stop there during migrations. This is especially a problem for Atlantic, Mississippi, and Pacific Flyways.
136
What is the definition of a wetland and what are the 3 types of wetlands?
Open-water habitats and seasonally or permanently waterlogged land areas.
Marshes, Swamps, Peatlands
137
What are some threats to Salt Marshes?
```
Embankment
Excessive agricultural use
Urbanization
Recreation
Coastal erosion
Pollution and industrial waste water
Invasion of Spartina anglica and Erytrigia (in eutrophic salt marshes)
```
138
What is the definition of a Taiga?
Northern circumpolar boreal forest. Not as as cold as tundra, there is a bit of rain
139
What is the definition of a Tundra?
An area in an arctic or alpine region, characterized by bare ground, no trees, and the growth of plants like mosses, lichens, sedges, forbes, and low shrubs.
140
Classification of Forest/woodland ecosystems is based on what?
Leaf longevity and period of leaf dormancy or leaf morphology
141
What are the two kinds of classifications for forest/woodland ecosystems?
Seasonal Leaf Longevity is deciduous, can be winter deciduous or drought deciduous (depending on when its dormant)
Non-seasonal Leaf Longevity is evergreen, can be broadleaf or needle-leaf
142
Describe stranglers and epiphytes
Stranglers are plants that grow using another plant as support. Despite being named stranglers, they are not parasitic. Their seeds land on top of the partner tree, then they germinate and their roots grow downward. This way they can get plenty of light.
Epiphytes are plants that grow on another plant, but are not parasitic, such as the numerous ferns, bromeliads, air plants, and orchids growing on tree trunks in tropical rainforests.
143
Describe the stratification of tropical rainforest. CO2, humidity, sunlight intensity, and temp distribution in tropical rainforest?
A rainforest can be vertically stratified into four levels: emergent canopy, upper canopy, lower canopy, and understory. CO2 and humidity are higher in the lower level because they are trapped by the upper and emergent canopy. It is 6*C cooler in the forest than outside.
144
Describe biodiversity in tropical rainforests
About 90% of non-human primates live in the tropical forests. Tropical rainforests make up only 6% of the forestland on the Earth, but have 50-80% of the plant species.
145
Retainers of nutrients in tropical rainforests vs. temperate deciduous forests
Most of the nutrients in tropical rainforests are in biological cycles, with a nutrient turnover rate of 24 weeks. In temperate deciduous forests, soil (and leaves on the ground) is a significant seasonal reservoir of nutrients.
146
Is net yield production in tropical rain forests higher than that in Wetlands?
Swamps and marshes have a higher mean net primary productivity than tropical rainforests.
147
What serves as a major retainer of nutrients in rainforests?
Biological cycles (see above)
148
Comparison of rainfall in grassland, savanna, and woodland
Woodland and forests have the most rainfall, and grassland has the least. Savanna is in the middle.
149
What type of biome is a pampas?
A temperate area where precipitation is insufficient to support trees (grasslands). The book defines pampas as “temperate South American grassland, dominated by bunchgrasses”
150
What is the driving force of the migration of the wildebeest in Serengeti?
Wildebeest migrate to chase the rain.
151
Permafrost and its ecological function
Permafrost is the perennially frozen subsurface that may be hundreds of layers deep. It impedes infiltration and maintains high soil moisture because it’s lower layers never melt, which allows plants to exist in dry areas of the Arctic.
152
What is the most severe ecological problem associated with temperate
grasslands globally?
Most of it has been converted to crop plantation.
153
What is estivation?
A dormant state employed by animals during a hot or dry period
154
What does CAFO stand for?
Concentrated Animal Feeding Operations
2500 pigs and 500 cattle
