Download Environmental Systems Test Review Texas Ecoregions Fill in the

Environmental Systems Test Review
Texas Ecoregions
Fill in the blank notes from Pineywoods to Edwards Plateau
1. What role does fire play in maintaining Texas eco-regions?
Fire is an integral component in the function and biodiversity of many natural habitats, and the
organisms within these communities have adapted to withstand, and even thrive in, periodic natural
wildfires. Fire is a natural rejuvenator, helping to curb disease, break down underbrush to be recycled,
improve the quality of vegetation, and give the vegetation a fresh new start. Fire also breaks down and
returns nutrients to the soil, enriching it and causing more fertile growth. Fire is important for keeping
trees and adjacent forests from encroaching into grasslands. In prairies, natural fires keep woody
growth under control.
2. What is the main threat to all Texas wildlife? What are other threats to wildlife & their habitats?
Habitat loss – urbanization, agriculture, non-native species, deforestation
Suppression of natural fires, reservoir construction, roadways
3. What ecoregion does most of Navarro County belong to? Blackland Prairie
4. How much land in Texas is privately owned? 97%
5. How does the climate change as you move across Texas - north to south & east to west?
Precipitation is higher in the east Temperature is higher in the south
6. What is the difference between flora & fauna of an area?
Flora – plants, fungi
Fauna – animals/wildlife, insects
7. Explain what an endemic species is. Only found in a specific area & nowhere else. Usually
endangered. Edwards Plateau region has a lot of endemic species.
8. What animal is over-populated in central Texas & adds to habitat degradation?
White-tailed deer
9. What is the state fish of Texas? Guadalupe Bass
10. List threatened/endangered species we have talked about in class.
Pineywoods – Red-cockaded woodpecker, Louisiana Pine Snake, Louisiana Black
Bear,paddlefish.
Prairies – alligator snapping turtle, Texas horned lizard
Gulf Coast – whooping crane, Attwater’s prairie chicken, sea turtles
South Tx Brush Country – ocelot, Texas tortoise, Texas indigo snake
Edwards Plateau – golden-cheeked warbler, black-capped vireo, Tx blind salamander, Barton
Springs salamander
Ecological Interactions
1. Define the ecological interaction of competition & give an example.
Organisms competing/fighting over limited resources. Birds eating seeds from same pasture.
Animals fighting over territories
2. Explain the difference between intraspecific vs. interspecific competition.
INTRAspecific competition – same species: wolves eating from same carcass
INTERspecific competition – different species: wolves, bear, ravens, foxes trying to eat from
same carcass.
3. How can competition among organisms be reduced?
Resource Partitioning – organisms using resources in different ways.
- Spatial & temporal
4. Define the ecological interaction of predation & give an example.
Predator kills & eats the prey. Lion eating a wildebeest. Dragonfly eating a small insect.
5. Explain adaptions that owls possess.
Large eyes – help them to see at nigh
Facial discs – directs sounds into ears (asymmetrical) – excellent hearing
Talons & beak – sharp, catch/kill prey
Feathers – silent flight
6. What kind of organisms can be found within an owl pellet ecosystem?
Bacteria, fungi, beetles, moths (not prey items that owls eat)
7. What is a symbiotic relationship (symbiosis)?
Close relationship b/w 2 or more organisms.
8. Define the symbiotic relationship of mutualism & give an example.
Both organisms benefit (+ +).
Oxpecker eating ticks off of a giraffe.
9. Define the symbiotic relationship of commensalism & give an example.
One organism benefits, the other is unaffected (+ 0)
Barnacles on whale, remoras swimming beside sharks
10. Define the symbiotic relationship of parasitism & give an example.
Parasite benefits and the host is harmed (+ -)
Leech on turtle/fish, tick on deer, tape worm in human.
11. Explain what nest parasitism is. What local bird is involved in this type of parasitism?
Birds laying eggs in other bird species’ nests.
Brown-headed cowbird
12. Compare & contrast biotic & abiotic factors within an ecosystem.
Biotic – living or once living – dead tree, scat, animals, plants
Abiotic – nonliving – soil type, rocks, temp, precip
Population Dynamics
1. What is a population? What do all members of a population have in common?
A group of the same species in a location
2. Understand the difference between population density, distribution, & dispersion.
Density - # of individuals/unit area
Distribution – where organism is found (range)
Dispersion – pattern how individuals are spaced
3. Explain the 3 types of population dispersion. Be able to recognize each pattern.
Clumped, Uniform, Random
4. Be familiar with the Lincoln Index equation and what it’s used for. Go over “Catfish
Population Estimate” worksheet.