Exercises
A. Give short answers.
1. Name the water masses surrounding North America.
2. Which water body joins the Atlantic Ocean to the Pacific Ocean
3. Name the three largest countries of North America.
4. Which are the four main physical features of North America?
5. Which is the most important river of North America? Name its main tributaries
6. Where is softwood mainly found in North America? Give a few uses of softwood
7. What work do loggers do?
B. Give reasons for the following
1. We know that the present continents were once joined together
2. There are many rapids and waterfalls at the eastern edge of the Piedmont
3. Lumbering is an important occupation in North America
9. Forests are very important for Canada's environment, society and economy.
C. Answer in some detail.
Answers
Answer:
1. North America is bounded on the north by the Arctic Ocean, on the east by the North Atlantic Ocean, on the south by the Caribbean Sea, and on the west by the North Pacific Ocean.
2. Drake Strait is the water body which joins the Atlantic Ocean to the Pacific Ocean.
3. The three largest countries of North America are Canada, United States and Mexico.
4. North America can be divided into five physical regions: the mountainous west, the Great Plains, the Canadian Shield, the varied eastern region, and the Caribbean.
5. Mississippi River is the most important river of North America. its main tributaries are Arkansas, lllinois , Missouri, Ohio and red River .
6. The northern portion of North America (Alaska, Canada and Newfoundland) is primarily coniferous, 90 percent of the softwoods and 7 percent of temperature hardwoods. Softwood is the source of 80% of worlds total timber.
7. A logger works in the lumber industry, cutting down trees and loading them for transportation. Typical job duties involve cutting, skidding, and pre-processing the logs. The logs are then processed into boards, paper, and other valuable materials. Most loggers work in teams of two to safely fell timber.
8. a. The continental drifthypothesis was developed in the early part of the 20th century, mostly by Alfred Wegener. Alfred Wegener said that contients move around on earth's surface and that they were once joined together as a single supercontinent.
b. Edge of the Piedmont/Coastal Plain, where various rivers cross from hard bedrock to soft sediments, is marked by a zone of rapids and waterfalls called the Fall Line. ... That physical pattern of rapids/waterfalls blocked ships from sailing further upstream, limiting water-based transportation of the European colonists.
c. The economic activity involving felling, hauling, logging of timber is known as lumbering. It is well developed in the coniferous forest belt of the cool temperate lands, because: ... (ii) The land and rivers freeze which makes transportation of the logs easy. (iii) The species of trees are few and the area is accessible.
9. Forests benefit Canadians environmentally with the rich ecosystem they support. This ecosystem preserves soils, cycles nutrients and supports biodiversity. Trees and other forest plants filter pollutants from air and water, acting as natural cleansers.