Exam II

Question 1

What are three benefits of wetlands? How has human development impacted wetlands? How
can one distinguish between basin, riverine and fringe wetlands?

Answer 1

Benefits of wetlands are they are very diverse communities, water storage basins, reduce flooding intensity, filter pollutants (improves water quality). Human development has impacted by being frequently destroyed/degraded, filled for agriculture and development, drained for development. Basin wetlands: develop in shallow basins, Range from upland upload depressions to filled in lakes and ponds. Riverine wetlands: Develop along shallow banks of rivers and streams, often flooded. Fringe wetlands: Found along edges of large lakes and seas, water flows back and forth due to changing lake levels.

Question 2

How is life different in each of the four life zones (littoral, limnetic, profundal, benthic) of a lake
or pond? Be sure to include a diagram and creature examples

Answer 2

Littoral: part lake, part forest, wet vegetation, Limnetic: water where the sunlight can enter, Profundal: deeper water thats dark, Benethic: Bottom, ground of lake.

Question 3

What conditions (temperature, water flow, and dissolved oxygen) do aquatic creatures face in
each of the regional zones (source, transition, floodplain) of a river?

Answer 3

Cooler water holds more dissolved oxygen than warmer water

Question 4

What do demography measures such as crude birth & death rates, net migration rate,replacement-level fertility, total fertility rate, and infant mortality tell us about populations? Are China & India managing their growing populations?

Answer 4

Crude birth rate: number born per 1000 in population. Crude death rate: number deaths per 1000 in population. Net migration rate ; immigration - emigration.replacement level fertility: number of offspring to replace parents. Total Fertility rate: number of children average woman will have during normal reproductive years. There is currently too many people than the overall environment can support.

Question 5

Consumption overpopulation

Answer 5

Fewer people in the population but each uses lots of resources, Too many for environment to support at that level.

Question 6

What can we learn from the three different types of population age structures (give examples)?
How does the demographic transition model predict population changes as countries develop?

Answer 6

Preindustrial stage: High birth rate, and high death rate (sharp upward pyramid). Transitional stage: Birth rate remains high and death rate decreases (normal pyramid). Industrial Stage: Birth and death rates declines (rounded pyramid). Demographic transition model explains how population changes based on the economy such as changes in healthcare, education, and business.

Question 7

Cultural carrying capacity

Answer 7

Maximum number that can be supported.

Question 8

How is natural extinction different from accelerated extinction? List & describe at least four
reasons why we should be concerned about species extinctions.

Answer 8

Loss of one plant species can cause loss of 30 animal species. We should be considered because health & money, aesthetics & recreation, ecosystem stability, and ethics.

Question 9

Differentiate between the biocentric, anthropocentric, and ecocentric ethics.

Answer 9

Biocentric: all creatures (or species) have the right to live, one species not more important than the other. Anthropocentric: Humans are the most important creatures on earth, no other creature had the right to live unless we give it that right. Ecocentric: Humans are a part of nature, protecting nature protects humans.

Question 10

Discuss the major causes (at least six) of accelerated species extinctions.

Answer 10

Habitat alteration, hunting for commercial products, introduction of exotic species, trophy hunting, pest & predator control, collecting organisms

Question 11

Lacey Act (1900)

Answer 11

Congress forbids interstate commerce in illegally killed wildlife

Question 12

Endangered species Act

Answer 12

Congress protect species from extintion, cannot hunt/trap/kill/collect these species, habitats cannot be altered or destroyed.

Question 13

Explain 4 main principles of conservation biology. Discuss fox control efforts.

Answer 13

1. Humans should not reduce biodiversity or disrupt natural functioning of ecosystems (nutrient cycles, fires, etc.) 2. Humans should not cause premature extinctions. 3. preserving habitats, niches, & ecosystems protect biodiversity; must restore degraded systems. 4. Humans should not interfere with the natural rate of change. Fox control efforts shooting/trapping/poison/burning/gassing dens. Using compound 1040.

Question 14

Conditioned taste aversion

Answer 14

sodium carbonate sprayed on hooded plover eggs, makes foxes sick, learns to avoid food next time.

Question 15

Explain how even-aged & uneven-aged forest management strategies are different. Describe
clearcutting, selective cutting and whole tree harvesting. How are they destructive to wildlife?

Answer 15

Even aged forest management: monocultures, same age and size; no species diversity few layer/complexity present.
Uneven Aged Management: many tree species present different ages and sizes; promote diversity of animal life. Clearcutting: 45 arces are cut timber and burn waster then replant trees. Whole tree harvesting (selective cutting) : stands of unevenly aged trees many diff species, Allows regeneration or damage to habitat and lttle erosion. While whole tree harvesting causes a lot of erosion.

Question 16

What are six main reasons for tropical deforestation? How can planting Neem trees and
debt-for-nature swaps help revegetate or protect forests?

Answer 16

cattle ranching, cash crops, dam creation, overpopulation, resources sold, slash and burn argiculture. Neem trees are fast growers in poor soil, leaf pesticides, Debt for nature swaps: debt purchased by nongovermental group, forgiven if land protected against deforestation and poaching,

Question 17

What are rangelands and how are they actively managed?

Answer 17

Grazing management: first line of defense controlling the number of animals and grazing duration. Range Improvement: control brush (burning), replant and fertilize baren areas, fences and water holes promote uniform grazing.

Question 18

Diagram & describe a typical soil profile (with horizons). Describe the 3 functions of humus.

Answer 18

O-horizon: thin layer of organic waste, detritus, dark rich color. A-horizon: varies in thickness from 1 inch to 2 ft tall, nutrient rich, supports crops, higher moisture because of humus. B-horizon: recieves & collects minerals & nutrients from above, lightly colored lacks humus. C-horizon: parent material. The 3 functions of Humus are retains moisture in soil, binds nutrients, releases nutrients in forms that plants use.

Question 19

Loam, detritus, leaching

Answer 19

Loam: mix of soil particles, fairly equal proportions of sand, silt, clay, best for agriculture. Detritus: plant and animal matter, from living organism, earthworms,plants. Leaching: nutrients washed into lower soil layers

Question 20

What problems do plants experience in clay & sandy soils? What is weathering? What happens to farmland as the result of the three main types of soil erosion?

Answer 20

Clay causes water log because they are small particles. Sand causes leaching as water washed through it also takes the needed plant material. Weathering: process, rock parent material is broken down into small particles. soil is lost in layers or sheets.

Question 21

Green & animal manures

Answer 21

Green Manures: green plants plowed into soil. Animal Manures: animal dung and urine

Question 22

Explain how crop rotation helps reduce problems such as low nutrient levels & disease.

Answer 22

prevents depletion of soil nutrients, reduces pests that specialize on particular crops, avoid planting same crops in same area year after year, alternate corn with legume for increase nitrogen.

Question 23

Malnutrition, undernutrition

Answer 23

Malnutrition: lack of proper nutrients and vitamins. Undernutrition: lack of calories

Question 24

Why do some people suffer from marasmus, kwashiorkor, rickets, goiter, and scurvy? What are their symptoms? What steps has UNICEF taken to prevent the deaths of children?

Answer 24

These are common diseases in the poor is the lack different vitamins and minerals received during intake of food. Symptoms are thin, bloated stomachs, joints filled with fluids, teeth lost. UNICEF has provided oral rehydration, world immunization, breast feeding education, sanitation education.

Question 25

Explain how industrialized agriculture is different from subsistence agriculture & nomadic
herding. What types of nontraditional foods do some humans eat?

Answer 25

Industrialized agriculture: less human labor high inputs of fertilizer and fossil fuels to run machines, pesticides and irrigation increase yields, grain, surplus is sold. Untraditional foods are insects

Question 26

What are the benefits of the green revolution and 2nd green revolution? What is meant by
“eating lower on the food chain”? Why is the distribution of food aid controversial to some?

Answer 26

Green revolution: increase crop yields since 1950, monoculture agriculture. high inputs of water, fertilizer, pesticides. 2nd Green revolution: 1967 selective breeding for tropical and subtropical climates.
Eating lower on the food chain refers to eating more vegetables and fruits and less meats.