2: Physical Geography - Geosciences
3.2 Physical Geography of the Region
South Asia’s Himalaya Mountains are the highest in the world, soaring to over 8,800 meters (29,000 feet). These are also some of the world’s youngest mountains, reflecting a region that has experienced significant physical and cultural changes throughout its history. Here, we find one of the earliest and most widespread ancient civilizations, the hearth area for several of the world’s great religions, and a region with a population that will soon be the largest on Earth.
South Asia is a distinct region in terms of its physical landscape. Formidable physical barriers separate the region from the rest of the Eurasian landmass. Much of the impressive physical geographic features of South Asia are the result of tectonic activity. Between 40 and 50 million years ago, the Indian Plate collided with the Eurasian plate. Both the Indian Plate and the Eurasian plate were comprised of reasonably low-density material, and so when the collision occurred, the two landmasses folded like an accordion creating the mountain ranges we see today. The Indian Plate is still moving towards the Eurasian plate today and over the next 10 million years, will move an additional 1,500 km (932 mi) into Asia.
This massive tectonic collision resulted in perhaps the most well-known physical feature in South Asia: Mount Everest. Everest, located in the Himalaya Mountain range on the border of Nepal and China, is the highest mountain in the world. Because the India Plate continues to collide with the Eurasian Plate, this mountain range is still tectonically active and is rising at a rate of 5 mm each year. Thus, if you are planning on scaling Mount Everest in ten years, be prepared to climb an extra two inches.
Although the Himalaya Mountains are well-known for having the highest peak, the Karakoram Mountain range, passing through Pakistan, India, China, and Afghanistan, has the highest concentration of peaks above 8,000 meters (26,000 feet). Its highest peak, K2, is the second-highest mountain in the world, and far fewer people have successfully made it to the top compared to Everest. One in four people dies while attempting to summit.
Another key physical feature of South Asia, the Deccan Plateau, was formed from the region’s tectonic activity. Around 65 million years ago, there was an enormous fissure in Earth’s crust, which led to a massive eruption of lava. The entire Indian peninsula was buried in several thousand feet of basalt, a type of dense, volcanic rock.
River Basins of China
Two major river systems provide fresh water to the vast agricultural regions of the central part of China Proper. The Yellow River (Huang He River) is named after the light-colored silt that washes into the river. It flows from the Tibetan highlands through the North China Plain into the Yellow Sea. Dams, canals, and irrigation projects along the river provide water for extensive agricultural operations. While wheat, sorghum, corn, and soybeans are common with vegetables, fruit, and tobacco grown in smaller plots. The North China Plain must grow enough food to feed its one thousand people per square mile average density. This plain does not usually produce a food surplus because of the high demand from the large population of the region. Beijing borders the North China Plain. Its nearest port, Tianjin, continues to expand and grow, creating an economic center of industrial activity that relies on the peripheral regions for food and raw materials. Cotton is an example of a key industrial crop grown here.
The Yangtze River (Chang Jiang River) flows out of the Tibetan Plateau through the Sichuan Province, through the Three Gorges region and its lower basin into the East China Sea. Agricultural production along the river includes extensive rice and wheat farming. Large cities are often located along this river, including Wuhan and Chongqing. Nanjing and Shanghai are situated near the delta on the coast. Shanghai is the largest city in China and is a growing metropolis. The Three Gorges Dam of the Yangtze River is the world’s largest dam. It produces a large percentage of electricity for central China. Oceangoing ships can travel up the Yangtze to Wuhan and, utilizing locks in the Three Gorges Dam, these cargo vessels can travel all the way upriver to Chongqing. The Yangtze River is a valuable and vital transportation corridor for transporting goods between periphery and core and between the different urban centers of activity. Sichuan is among the top five provinces in China in terms of population and is dependent on the Yangtze River system to provide for its needs and connect it with the rest of China.
Northeast China was formerly known as Manchuria, named after the Manchu ethnic group, which had dominated the region in Chinese history. Two river basins create a favorable industrial climate for economic activity. The lower Liao River Basin and the Songhua River Basin cut through Northeast China, along the cities of Harbin and Shenyang to be located there. This region is known as the Northeast China Plain. It has extensive farming activities located next to an industrial landscape of smokestacks, factories, and warehouses. Considerable mineral wealth and iron ore deposits in the region have augmented the industrial activities and have created severe environmental concerns because of excessive air and water pollution. In its zenith in the 1970s, this was China’s leading steel production area, but the region is being reduced to a rustbelt since many of China’s manufacturing centers are now being developed in the southern regions of China Proper.
The southernmost region of China Proper is home to the Pearl River Basin, an important agricultural and commercial district. Though smaller in size than the Yangtze River Basin, major global urban centers are located on its estuary, where the mouth of the river flows into the South China Sea. The system includes the Xi River, Pearl River, and their tributaries. As the third-longest river system in China, these rivers process an enormous amount of water and have the second-highest volume of water flow after the Yangtze. Guangzhou, Macau, and Hong Kong are the most significant cities in the rapidly expanding industrial center of Shenzhen. As mentioned earlier, Macau was a former Portuguese colony, and Hong Kong was a former British colony. These urban areas are now hubs for international trade and global commerce. Guangzhou is one of China’s largest cities, along with Shanghai, Beijing, Wuhan, and Tianjin. Cantonese heritage and traditions form a foundation for the cultural background of the people who live here.
China Doesn’t Want Your Trash
Watch the video “China Doesn’t Want Your Trash” from PolyMatter and consider the following:
- Why was China buying the majority of the world’s trash?
- Describe why China decided to stop accepting the world’s trash in 2017.
- Three Gorges Dam (The New China Dam)
The Three Gorges Dam on the Chang Jiang River (also called the Yangtze River) is known in China as the New China Dam. Its hydroelectric production system is the largest on Earth. The river system is the world’s third longest, after the Nile and the Amazon. Ideas for this project go back to the days just after the last dynasty fell. Plans and development began in the decades before 1994 when the construction of the dam began. The primary purposes of the dam are to control the massive flooding along the Chang Jiang, produce hydroelectric power, and increase shipping capacity along the river.
- Dam length: 7,661 feet
- Dam height: 610 feet
- Dam width (at base): 377 feet
- Physical construction began December 14, 1994
- Construction cost: estimated thirty-nine billion US dollars
- Estimated surface area of the reservoir: 403 square miles
- Estimated length of the reservoir: 375 miles
- Capacity of thirty-two generators totaling 22,500 MW (equivalent to about twenty nuclear power plants the size of the Watts Bar 1, the newest US nuclear reactor)
Before the construction of the dam, flooding along the Chang Jiang cost thousands of lives and billions of dollars in damage. In 1954, the river flooded, causing the deaths of more than thirty-three thousand people, and displacing an additional eighteen million people. The large city of Wuhan was flooded for three months. In 1998, a similar flood caused billions of dollars in damage, flooded thousands of acres of farmland, resulted in more than 1,526 deaths, and displaced more than 2.3 million people. The dam was rigorously tested in 2009 when a massive flood worked its way through the waterway. The dam was able to withstand the pressure by containing the excess water and controlling the flow downstream. The dam saved many lives and prevented billions of dollars in potential damage. The savings in human lives and in preventing economic damage are projected to outweigh the dam’s ecological destruction and financial cost within a few decades.
The dam produces most of the electricity for the lower Chang Jiang Basin, including Shanghai, the largest city in China. Five years of the dam producing electricity has already paid for about one-third of its construction costs, which is equivalent to burning approximately 150 million tons of coal (depending on coal quality). This reduces the emission of millions of tons of carbon dioxide, sulfur, and nitrogen oxides into the atmosphere, which reduces air pollution and does not contribute to climate change. Heavy freight traffic on the Yangtze was the norm even before the dam was built in fact, it has the highest rates of transport of any river. The building of the dam has augmented the amount of freight traffic.
All the positive attributes of the Three Gorges Dam have contributed to the economic development of China. This is a testimony to the engineering and technological capacity of the nation. However, this project has also created its problems and negative impacts on culture and the environment. By 2008, the number of people forced to relocate from the flooding of the reservoir had reached 1.24 million. Historic villages and hundreds of archaeological sites were flooded. Thousands of farmers had to be relocated, without compensation, to places with less productive soils. Sadly, much of the scenic beauty of the river basin is now underwater.
Animal species like the critically endangered Siberian Cranes, who had wintered in the former wetlands of the river, had to find habitat elsewhere. The endangered Yangtze River Dolphin has been doomed to extinction because of the dam and the amplified river activity. The dam restricts the flushing of water pollution and creates a massive potential for landslides along its banks, exacerbating the potential for the silting in of the reservoir and the clogging of the dam’s turbines. The dam also sits on a fault zone, and there is a concern that the water’s massive weight in the reservoir could trigger earthquakes that may destroy the dam, with catastrophic consequences. Large development projects tend to have an enormous impact on the people and the environment that inhabit their shadow. The building of the Three Gorges Dam has created controversy, with strong arguments on both sides of the issues. Other large dams are being proposed to complicate the situation further or are under construction along the same river.
North America: Physical Geography
Encyclopedic entry. North America, the third-largest continent, extends from the tiny Aleutian Islands in the northwest to the Isthmus of Panama in the south.
Earth Science, Geology, Meteorology, Geography, Physical Geography
North America, the third-largest continent, extends from the tiny Aleutian Islands in the northwest to the Isthmus of Panama in the south. The continent includes the enormous island of Greenland in the northeast and the small island countries and territories that dot the Caribbean Sea and western North Atlantic Ocean. In the far north, the continent stretches halfway around the world, from Greenland to the Aleutians. But at Panama&rsquos narrowest part, the continent is just 50 kilometers (31 miles) across.
North America&rsquos physical geography, environment and resources, and human geography can be considered separately.
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. Mexico and Central America&rsquos western coast are connected to the mountainous west, while its lowlands and coastal plains extend into the eastern region.
Within these regions are all the major types of biomes in the world. A biome is a community of animals and plants spreading over an extensive area with a relatively uniform climate. Some diverse biomes represented in North America include desert, grassland, tundra, and coral reefs.
Young mountains rise in the west. The most familiar of these mountains are probably the Rockies, North America&rsquos largest chain. The Rockies stretch from the province of British Columbia, Canada, to the U.S. state of New Mexico.
The Rocky Mountains are part of a system of parallel mountain ranges known as the Cordilleras. A cordillera is a long series of mountain ranges. Although cordilleras exist all over the world, in North America, &ldquothe Cordilleras&rdquo indicate the massive mountain ranges in the western part of the continent. The Cordilleras extend from Canada all the way to the Isthmus of Panama.
The Sierra Madre mountain system is part of the Cordilleras. The Sierra Madre stretch from the southwestern United States to Honduras. The Sierra Madre include many high volcanoes (up to 5,636 meters, or 18,500 feet) that stretch across Mexico south of the cities of Guadalajara and Mexico City.
Volcanic mountain ranges in Guatemala, Honduras, Nicaragua, Costa Rica, and Panama are also considered part of the Cordilleras. Volcanic eruptions and earthquakes occur frequently in this region. Volcanic activity can destroy towns and cities. It also contributes to the rich, fertile soils of the region.
Some of the Earth&rsquos youngest mountains are in the Cascade Range of the U.S. states of Washington, Oregon, and California. Some peaks began to form only about a million years ago&mdasha blink of an eye in Earth&rsquos long history. The mountains include temperate rain forest&mdasha biome unique to the area. The temperate rain forest receives an incredible amount of precipitation, between 254 to 508 centimeters (100 to 200 inches) annually. However, its cool winters and mild summers promote the growth of mosses, ferns, fungi, and lichens.
The temperate rain forest supports a wide variety of life. The Sitka spruce, western red cedar, and Douglas fir are trees native to North America&rsquos temperate rain forest. Some of these trees grow to more than 90 meters (300 feet) tall and 3 meters (10 feet) in diameter. Black bears, Roosevelt elk, and marmots are indigenous animal species.
The three major desert regions of North America&mdashthe Sonoran, Mojave, and Chihuahuan&mdashare all in the American southwest and northern Mexico. These large deserts are located in the rain shadows of nearby mountains. The mountains block precipitation and accelerate the movement of hot, dry wind over these regions. The Sonoran is in the rain shadow of the Coast Ranges, the Mojave is in the shadow of the Sierra Nevada, and the Chihuahuan is in the shadow of the Sierra Madre.
Notable desert plant species includes the saguaro cactus, Joshua tree, and mesquite. Animal species include the roadrunner, Gila monster, and rattlesnake.
In addition to mountains, deserts, and forests, the northern part of the western region of North America also has the richest deposits of oil and natural gas on the continent. Most of these deposits are located offshore, in the Arctic and Pacific Oceans.
The Great Plains lie in the middle of the continent. Deep, rich soil blankets large areas of the plains in Canada and the United States. Grain grown in this region, called the &ldquoBreadbasket of North America,&rdquo feeds a large part of the world. The Great Plains are also home to rich deposits of oil and natural gas.
Much of the fertile soil was formed from material deposited during the most recent glacial period. This ice age reached its peak about 18,000 years ago. As glaciers retreated, streams of melted ice dropped sediment on the land, building layers of productive soil.
The grassland or prairie regions of the Great Plains make up the largest biome in North America. Extreme weather prevents the growth of large plants but is perfectly suited to the native grasses that dominate the region.
Native grasses vary in size from 2 meters (7 feet) in tallgrass prairies to only 20 or 25 centimeters (8 or 10 inches) in shortgrass prairies. Native animal species include bison, prairie dogs, and grasshoppers.
The Canadian Shield is a raised but relatively flat plateau. It extends over eastern, central, and northwestern Canada. The Canadian Shield is characterized by a rocky landscape pocked by an astounding number of lakes.
The tundra, stretching along the northern borders of Alaska and Canada to the Hudson Bay area, is a biome common to the Canadian Shield. Tundra is where low temperatures and precipitation levels hinder tree growth. The tundra is characterized by permafrost&mdashsoil that is frozen for two or more years. This permafrost keeps moisture near the soil&rsquos surface, promoting vegetation growth even in the extreme, Arctic conditions of the tundra.
During the summer, this top layer of soil thaws less than 10 centimeters (only a few inches) down, forming numerous shallow lakes, ponds, and bogs. Lichens, mosses, algae, and succulents take advantage of these shallow waters. In turn, they provide food for the caribou and musk ox that are typical of this area.
This varied region includes the Appalachian Mountains and the Atlantic coastal plain.
North America&rsquos older mountain ranges, including the Appalachians, rise near the east coast of the United States and Canada. These areas have been mined for rich deposits of coal and other minerals for hundreds of years.
The Atlantic coastal plain extends from river, marsh, and wetland regions east of the mountains toward the sandy beaches of the Atlantic coast. Wetland areas are a biome of the eastern region and consist of areas of land whose soil is saturated with permanent or seasonal moisture. The Florida Everglades is the largest wetland system in the United States, covering more than 11,137 square kilometers (4,300 square miles) of southern Florida.
The Everglades is a biologically diverse region and contains several bordering ecosystems. Sawgrass marshes are the most iconic plant community of the Everglades and thrive on the slow-moving water of the wetlands. Alligators nest in the sawgrass, while wading birds such as egrets, herons, spoonbills, and ibises make their breeding grounds in other wetland tree species, such as cypress and mangrove.
The Caribbean Region includes more than 7,000 islands, islets, reefs, and cays. The region&rsquos islands and smaller islets are varied in their topography some have relatively flat and sandy terrain while others are rugged, mountainous, and volcanic.
The coral reefs and cays of the Caribbean Sea are among the most spectacular biomes in North America. A reef is a ridge of jagged rock, coral, or sand just above or below the surface of the sea. Some coral reefs surround islands, such as the Bahamas, Antigua, and Barbados. Others are found off the Florida Keys, a chain of cays&mdashsmall islands situated on a coral reef platform&mdashnear the southern coast of the U.S. state of Florida.
Coral reefs are made of millions of tiny animals&mdashcorals&mdashthat form a hard shell around their bodies. This hard surface provides a rich community for algae and plants such as seagrass. Brightly colored tropical fish, as well as sharks, sea turtles, sea stars, and sea horses, are animals native to the Caribbean&rsquos coral reefs.
North America&rsquos varied landscape features many natural wonders. It has deep canyons, such as Copper Canyon in the Mexican state of Chihuahua. Denali, the continent&rsquos highest peak, stands at 6,194 meters (20,320 feet) within Denali National Park and Preserve in the U.S. state of Alaska. Yellowstone National Park, in the U.S. states of Wyoming, Montana, and Idaho, has some of the world&rsquos most active geysers. Canada&rsquos Bay of Fundy has the greatest tidal range in the world. The Great Lakes form the planet&rsquos largest area of freshwater. The Mississippi River, at 3,730 kilometers (2,320 miles) long, is one of the longest river systems in the world and drains all or parts of 31 U.S. states.
North America, stretching from the polar Arctic to the tropical Caribbean, supports almost all major types of biomes.
Map by the National Geographic Society
Most Renewable Electricity Produced
Belize (96.7% hydropower, biomass)
57 people per square kilometer
Mississippi River (3 million square kilometers/1.15 million square miles)
Denali, Alaska, United States (6,190 meters/20,310 feet)
Largest Urban Area
New York City, United States (23.7 million people)
We talked about geography recently over at A Delectable Education podcast, but as we try to limit each episode to a reasonable bite-sized morsel, there are times when we have to leave something out that one of us really wanted to focus on. For me, and my ever-present science focus, it was the details Mason provided us regarding physical geography for elementary students.
It seems to me a sine quâ non of a living education that all school children of whatever grade should have one half-day in the week, throughout the year, in the fields. There are few towns where country of some sort is not accessible, and every child should have the opportunity of watching from week to week, the procession of the seasons.
Geography, geology, the course of the sun, the behaviour of the clouds, weather signs, all that the ‘open’ has to offer, are made use of in these walks but all is incidental, easy, and things are noticed as they occur. (3/237)
Mason points out that geography for the young child should mostly be taught by-the-way. Instead of treating geography solely as a book subject at this age, we should be outside looking at a little creek and then comparing it to the great rivers of the world, or looking at a hill and comparing it to the great mountain ranges. She called this ‘pictorial geography,’ which means we use something accessible to us to foster the child’s imagination about other things in the world that they cannot see. She even said that “There are certain ideas which children must get from within a walking radius of their own home if ever they are to have a real understanding of maps and of geographical terms.” (1/73)
Mason outlines the order in which each concept should be covered, and interestingly, each idea builds on another until the abstract ideas of direction, weather, and distance come together in a very tangible way for children. The following list is in the order she suggests presenting these ideas to our children:
- The position of the sun in the sky as the day goes by, and how it helps us know what time of day it is. They can even note, in their nature journals, the time and location of sunrise and sunset over the course of a year, to see how it changes. They can be made to notice that when the sun is high in the sky on a summer day, it’s much warmer than when the sun is low in the sky in the middle of a winter afternoon. They may also notice the difference these things make for their shadow.
- They can even learn a little about the size of the sun and the earth and the fact that the earth moves around the sun. Mason explains that these concepts, while abstract, can be of interest to a child who has a great deal of imagination and faith in seemly impossible things. (I just love that.)
- They can learn basic information about the weather as it is experienced, again noting it in their nature journal.
- They can learn about distance, by measuring the steps it takes to walk a certain path near your home. By measuring how many feet are covered by one of their steps, they can calculate the distance of a certain walk just by counting their steps.
- Once they understand the concept of distance they can learn the time it takes to cover a certain distance, and they can calculate the distance of a walk based on how long it took.
- Once they understand the progress of the sun, and a little about distance, the concept of direction－north, south, east and west－can be introduced, by coaching the child to stand with his right arm out toward the east (where the sun rises,) his left to the west (where the sun sets,) and his face pointed toward the north. Of course, then south is behind him. Then he can determine things like which side of his house faces south.
- After this, they will be ready to notice which direction the wind is blowing, by noticing which way the smoke from a chimney is going, or even which way a bit of dirt or grass falls when tossed in the air. You can tell them that the same way we are labeled by where we come from, (American’s come from America,) the wind is labeled by where it comes from. So for those of us in the northern hemisphere, the “North wind doth blow” from the north, bringing with it cold air, and the south wind brings warmer air.
- Following this basic understanding about directions, they can be introduced to the compass, and learn to use it to find direction.
- At this point, they can use their understanding of direction to accurately describe boundaries. They can say, our property is bordered by a cornfield on the north side and the main street is the south boundary of our yard.
- All the while they should be noticing what kinds of crops grow nearby, what animals are raised locally, and what kinds of rocks and trees can be found in the neighborhood.
- This culminates in the child drawing maps of various areas studied. They don’t have to draw them on paper, at least not at first, but rather they can be drawn in the dirt with a stick. They can note the boundaries and various structures, or where there is tree cover or a meadow. They can also note where north, south, east and west is on their map. They may find it hard to draw their map to scale at first, but eventually, they will learn about to pace off a boundary and allow an inch for 10 feet or some such.
Each of these things, the sun, weather, distance, direction, and boundaries, is covered by-the-way. There is no specific curriculum to follow, but you can see that by taking them generally in the order outlined above, one idea will lay the groundwork for the understanding of another idea. The only requirement is that you do need to spend ample time outside with your children and that you are deliberate about noticing all there is to notice about the geography of where you are at. Each day you and your children will find something new to notice. One day the wind is blowing, but from which direction? And then the next day it’s snowing. The western boundary of trees blocks some of the snow, but the meadow is covered evenly. The sun comes out the next day, making the snow sparkle, but it is low in the sky, and therefore does not produce enough heat to melt the snow. And on and on it goes. All of this lays the foundation for learning the geography of other places later on by the use of maps.
In addition, pictorial geography lays the foundation for understanding descriptions your children will read in history and geography books. Charlotte Mason said:
By-and-by he will have to conceive of things he has never seen: how can he do it except by comparison with things he has seen and knows? By-and-by he will be called upon to reflect, understand, reason what material will he have, unless he has a magazine of facts to go upon? The child who has been made to observe how high in the heavens the sun is at noon on a summer’s day, how low at noon on a day in mid-winter, is able to conceive of the great heat of the tropics under a vertical sun, and to understand the climate of a place depends greatly upon the mean height the sun reaches above the horizon. (1/66)
Physical Geography Books:
Form I (grades 1-3,) has 10 minutes, twice a week allocated on the morning schedule to book work for geography, and form II (grades 4-6,) has 20 minutes, twice a week. I would use one of those two time slots for a physical geography book. You could certainly use Mason’s first geography book (online), o r you could use several short books on various topics. You might even want to see if your library has them available. Some of my favorites are below:
What Makes a Shadow? by Clyde Bulla (LRFO 1)
What Makes Day and Night by Franklyn M. Branley (LRFO 1)
Sun Up, Sun Down by Gail Gibbons
Energy from the Sun by Melvin Berger (LRFO)
Follow the Sunset by Herman and Nina Schneider
The Moon Seems to Change by Franklyn M. Branley (LRFO 2)
North, South, East, and West by Franklyn Mansfield Branley (LRFO)
The Planets in Our Solar System by Franklyn M. Branley (LRFO 2)
What the Moon is Like by Franklyn M. Branley (LRFO 2)
The Sky Is Full of Stars by Franklyn M. Branley (LRFO 2)
The Sun: Our Nearest Star by Franklyn M. Branley (LRFO 2)
Clouds by Anne Rockwell (LRFO 1)
Not only for ducks: The story of rain by Glenn Orlando Blough
Rain and Hail by Franklyn M. Branley (LRFO)
Flash, Crash, Rumble, and Roll by Franklyn M. Branley (LRFO 2)
Down Comes the Rain by Franklyn M. Branley (LRFO 2)
A Drop Of Water: A Book of Science and Wonder by Walter Wick
Snowflake Bentley by Jacqueline Briggs Martin
AND Snowflakes in Photographs by W. A. Bentley (a book of Bentley’s photographs)
The Big Storm by Bruce Hiscock
Snow by Thelma Harrington Bell
Snow Is Falling by Franklyn M. Branley (LRFO 1)
For Reference or further reading on this subject, read Mason’s own words in H ome Education (vol 1), part 2, ch 9: Out-Of-Door Geography, pp. 71-78
Este artículo analiza la diferente incidencia que muestra la erosión estimada de suelos en las áreas de influencia socioeconómica de los Parques Nacionales de Doñana y Sierra Nevada en el marco de los procesos de Naturbanización. La Naturbanización se define por la capacidad de atracción de población y actividades económicas hacia las áreas de influencia socioeconómica de espacios protegidos debida al reconocimiento de sus valores ambientales y paisajísticos. Se establece la metodología de procesado de datos con un Sistema de Información Geográfica para llevar a cabo el estudio diacrónico de los valores estimados de erosión que proporciona la Junta de Andalucía ara toda la Comunidad Autónoma. Aplicando dicha metodología a las cuencas del arroyo de El Partido y del río Trevélez se pretende contribuir a una mejor comprensión de las relaciones de causalidad o de potenciación existentes entre los factores climáticos, las actividades humanas y los procesos erosivos. Se ha llevado a cabo un análisis estadístico de las cartografías raster publicadas de estimación de erosión media mensual y de las variables empleadas para su cálculo entre 2003 y 2014. Se ha constatado la relevancia que los usos y coberturas vegetales tienen como variable clave para explicar la distribución de los valores medios de erosión en ambas cuencas. En la cuenca del río Trevélez la evolución de las tasas de erosión estimada ha mostrado un mayor paralelismo con la erosividad de la lluvia, mientras que en el arroyo de El Partido han sido los cambios de usos del suelo los que determinan en mayor medida dicha evolución.
(a). Introduction to Geography
Spatial Tradition - the investigation of the phenomena of geography from a strictly spatial perspective.
Area Studies Tradition - the geographical study of an area on the Earth at either the local, regional, or global scale.
Human-Land Tradition - the geographical study of human interactions with the environment.
Earth Science Tradition - the study of natural phenomena from a spatial perspective. This tradition is best described as theoretical physical geography.
Today, the academic traditions described by Pattison are still dominant fields of geographical investigation. However, the frequency and magnitude of human mediated environmental problems has been on a steady increase since the publication of this notion. These increases are the result of a growing human population and the consequent increase in the consumption of natural resources. As a result, an increasing number of researchers in geography are studying how humans modify the environment. A significant number of these projects also develop strategies to reduce the negative impact of human activities on nature. Some of the dominant themes in these studies include: environmental degradation of the hydrosphere, atmosphere, lithosphere, and biosphere resource use issues natural hazards environmental impact assessment and the effect of urbanization and land-use change on natural environments.
Considering all of the statements presented concerning the history and development of geography, we are now ready to formulate a somewhat coherent definition. This definition suggests that geography, in its simplest form, is the field of knowledge that is concerned with how phenomena are spatially organized. Physical geography attempts to determine why natural phenomena have particular spatial patterns and orientation. This online textbook will focus primarily on the Earth Science Tradition . Some of the information that is covered in this textbook also deals with the alterations of the environment because of human interaction. These pieces of information belong in the Human-Land Tradition of geography.
The three longest rivers of the realm, Mekong, Red, and Irrawaddy, are located on the mainland and have their headwaters in the high elevations of the Himalayan ranges of China. The Mekong River makes its way from the high Himalayas in China and helps form the political borders of Laos and Thailand on its way through Cambodia to Vietnam, where it creates a large delta near Ho Chi Minh City (Saigon). The Red River flows out of China and through Hanoi to the Red River delta on the Gulf of Tonkin. The Irrawaddy River flows through the length of Burma, providing for the core area of the country. Another major river of the mainland is the Chao Phraya of Thailand. With its many tributaries, the Chao Phraya creates a desirable core area that is home to the largest population. Many other rivers can be found on both the mainland and the insular region. The rivers transport water and sediments from the interior to the coasts, often creating large deltas with fertile soils that are major agricultural areas. Multiple crops of rice and food products can be grown in the fertile river valleys and deltas. The agricultural abundance is needed to support the ever-increasing populations of the realm.
Access to Fresh Water
Water is one of the necessities for human existence, and human settlements have long been based on the availability of water for human consumption and agriculture, navigation, and the production of energy. In North Africa and Southwest Asia, water availability is of even greater relevance because of the dominant type B climate. Methods used to address the shortage of water or access freshwater have been nearly as diverse as those living here. Large populations of people can be found wherever there is fresh water. Water has historically been transferred from source to destination through canals, aqueducts, or select channels. Many ruins of extensive aqueducts from Roman times and earlier remain throughout the realm. The issues associated with water use continue to affect the lives of the people of this realm. Rapid population growth and industrialization have intensified the demand for freshwater.
Water can be found in the desert regions in a range of forms. For example, there are oases, springs, or noted wells from which people can draw underground water close to the surface. Mountainous regions such as the Atlas Mountains in North Africa or the Elburz Mountains in Iran trap moisture, which produces higher quantities of precipitation. The precipitation is then available in the valleys to irrigate crops. Discovering or developing other methods of acquiring freshwater is a requirement in areas without mountains.
Underground Water in Libya
In the Sahara region, Libya draws water from deep underground wells that tap into the vast aquifers beneath the desert that were charged with water when the region was tropical thousands of years ago. The water is referred to as fossil water. Extensive systems of canals and pipelines have been developed in Libya to extract fossil water and use it for agricultural production or urban purposes. The human-made river project, one of the largest of its kind, has drawn fresh water from the desert too large cities like Tripoli and Benghazi. The local drinking water in Benghazi is contaminated by saltwater intrusion from the Mediterranean. Underground aquifers are underneath political boundaries, so the allocation and control of water are matters of political debate that can lead to military conflict. The project’s potential duration will be how quickly the water is used and how many people use the aquifer system. The main problem with this system is that underground aquifers are not considered a renewable resource as more countries tap into the aquifers, the available water will be depleted more quickly. As water is drawn from the aquifers for industrial irrigation, the water table goes down. Local settlements that rely on well water may, in time, have to dig deeper wells or move to locations where water resources are still available.
Nile Water in Egypt
Egypt draws water from the Nile to irrigate fields for extensive food production. For thousands of years, floods of the Nile annually covered the land with fresh silt and water. This made the land productive, but the flooding often caused severe damage to human infrastructure. The building of the Aswan High Dam in the 1970s helped control the flooding of the Nile Valley. The river no longer flooded annually, and water had to be pumped onto the land. Over time, the constant and extensive use of this type of irrigation causes the small quantities of salt in the water to build up in the soil to severe levels, thereby reducing the land’s productivity. This process, called salinization, is a common problem in arid climates. To rid the salts’ soil, freshwater is needed to flood the fields, dissolving the salt and then moving the salty water back off the fields. High salinization in the soil and the reduction in agricultural productivity is a growing concern for Egypt. Egypt’s growing population places a high demand on the availability of food. More than half of the eighty million people in Egypt live in rural areas, and many of them make their living in agriculture, growing food that plays a critical role in the country’s economic stability.
Water from the Tigris and Euphrates
The primary source of water in the Fertile Crescent region comes from the Tigris and Euphrates rivers. Both have their origins in Turkey and converge at the Shatt al-Arab waterway that flows into the Persian Gulf. The Euphrates is the longest river in Southwest Asia and flows through Syria from Turkey before entering into Iraq. Turkey had developed large dams on both the Tigris and Euphrates for agricultural purposes and hydroelectric power. As water is diverted for agriculture in Turkey, there is less water flowing downstream for Syria or Iraq.
Disputes over water resources continue to be a significant concern in the Tigris-Euphrates Basin. The Atatürk Dam in Turkey is the largest dam on the Euphrates, and it has a reservoir behind the dam that is large enough to hold the total annual discharge of the river. All three countries have dams on the Euphrates, and both Turkey and Iraq have dams on the Tigris. The three countries signed a memorandum of understanding in 2009 to strengthen cooperation within the Tigris-Euphrates Basin. All three countries need water for agriculture to produce food for a growing population. Agreements to share water have been challenging due to the Iraq War and the recent protests and demonstrations in Syria that have contributed to further political tension between the three countries.
Water Conservation in Israel
Israel has taken innovative steps to conserve water and use it efficiently. Drip irrigation mixed with fertilizers is called fertigation. Fertigation is used extensively in the area. Israel grows plantation crops such as bananas, which require large quantities of water. Banana groves are covered with a material that allows sunlight to penetrate but reduces the amount of transpiration, conserving water. Israel has worked on recycling water whenever possible. Gray water is water extracted from sewage that has been treated to be used in agriculture. Underground wells in the West Bank region provide water for a high percentage of people in the Palestinian areas and Israel. The issue of control over the water is contentious at times. Just as water control may have been an essential factor in the early Mesopotamian civilizations, it remains a point of political conflict in places like Israel and the West Bank. The lack of freshwater and the more substantial demand placed on water resources have caused countries to afford it to desalinize seawater. This process is used extensively in the oil-rich states of the Arabian Peninsula. Israel is implementing a similar plan to accommodate its increasing population and freshwater requirements.
Mountain Water in Iran
Iran is mostly a desert climate thus, most countries do not receive copious amounts of precipitation. To redistribute the water available from the high mountains, Iranians have developed a system of qanats to collect water where it is available and channel it to the cities or urban areas for use. A qanat might include a system of shafts or wells along a mountain slope that allows water to collect into a common underground channel, diverted to wherever it is needed. This system has been in use since ancient times in many arid regions of the realm and around the world. More than 2,700 years ago, a qanat was developed in what is present-day Iran. The qanat has a system of hundreds of wells and channels water for more than twenty-eight miles it still provides drinking water to more than forty thousand people in the city of Gonabad. Thousands of qanats were developed over the centuries in this area. Persians used cold qanat water from the mountains to keep ice cool during the summer months. Agricultural production relies heavily on water from qanats, which depends on climate conditions and local weather patterns.
South America: Physical Geography
Encyclopedic entry. South America is a continent of extremes. It is home to the world's largest river (the Amazon) as well as the world's driest place (the Atacama Desert).
Biology, Earth Science, Geology, Meteorology, Geography, Physical Geography
South America, the fourth-largest continent, extends from the Gulf of Darién in the northwest to the archipelago of Tierra del Fuego in the south.
South America&rsquos physical geography, environment and resources, and human geography can be considered separately.
South America can be divided into three physical regions: mountains and highlands, river basins, and coastal plains. Mountains and coastal plains generally run in a north-south direction, while highlands and river basins generally run in an east-west direction.
South America&rsquos extreme geographic variation contributes to the continent&rsquos large number of biomes. A biome is a community of animals and plants that spreads over an area with a relatively uniform climate.
Within a few hundred kilometers, South America&rsquos coastal plains&rsquo dry desert biome rises to the rugged alpine biome of the Andes mountains. One of the continent&rsquos river basins (the Amazon) is defined by dense, tropical rain forest, while the other (Paraná) is made up of vast grasslands.
With an unparalleled number of plant and animal species, South America&rsquos rich biodiversity is unique among the world&rsquos continents.
Mountains & Highlands
South America&rsquos primary mountain system, the Andes, is also the world&rsquos longest. The range covers about 8,850 kilometers (5,500 miles). Situated on the far western edge of the continent, the Andes stretch from the southern tip to the northernmost coast of South America. There are hundreds of peaks more than 4,500 meters (15,000 feet) tall, many of which are volcanic.
The highest peak in the Andes, Aconcagua, stands at 6,962 meters (22,841 feet) and straddles the Argentina-Chile border. Aconcagua is the tallest mountain outside Asia.
High plateaus are also a feature of the Andes. The altiplano of Peru and Bolivia, for example, has an elevation of about 3,700 meters (12,300 feet). The Patagonia region of Argentina and Chile consists of lower-elevation plateaus and rugged glaciers.
Most plants in the alpine biome are small, and their leaves are stiff and strong to protect them from frost and drought. The largest herb in the world, Puya raimondii, is known as the Queen of the Andes. A Puya raimondii can live for 100 years and can grow to more than 9 meters (30 feet) tall. The leaves of this endangered species all grow from one woody stem, allowing moisture to run down the leaves to the base of the plant.
Outside the Andes, South America has two principal highland areas: the Brazilian Highlands and the Guiana Highlands. Located south of the Amazon River in Brazil, the Brazilian Highlands are made up of low mountains and plateaus that rise to an average elevation of 1,006 meters (3,300 feet). The Guiana Highlands are located between the Amazon and Orinoco Rivers. The heavily forested plateau of the Guiana Highlands covers southern Venezuela, French Guiana, Guyana, northern Brazil, and a portion of southeastern Colombia.
South America has three important river basins: the Amazon, Orinoco, and Paraguay/Paraná.
The Amazon River basin has an area of almost 7 million square kilometers (2.7 million square miles), making it the largest watershed in the world. The basin, which covers most of northern South America, is fed by tributaries from the glaciers of the Andes. Every second, the Amazon River empties 209,000 cubic meters (7,381,000 cubic feet) of freshwater into the Atlantic Ocean.
The Amazon River is the life force of the equally vast Amazon rain forest, which makes up about half of the rain forest of the entire planet. This tropical biome has as many as 100 different tree species on a single acre, including the rubber tree, silk cotton tree, and Brazil nut tree. Other important plant species include palms, ferns, and ropelike vines known as lianas that network throughout the rain forest&rsquos dense canopy.
The diversity of animal life in the Amazon rain forest is unsurpassed in the rest of the world. The rain forest is perfectly suited for arboreal, or tree-living, animals. More than 2 million species of insects are native to the region, including hundreds of spiders and butterflies. Primates are abundant&mdashhowler monkeys, spider monkeys, and capuchin monkeys&mdashalong with sloths, snakes, and iguanas. Thousands of native birds include brightly colored macaws, parrots, toucans, and parakeets.
The Orinoco River flows north of the Amazon. The Orinoco flows in a giant arc for more than 2,736 kilometers (1,700 miles), originating in the Guiana Highlands of northern Brazil and discharging in the Atlantic Ocean in Venezuela. The Orinoco River basin covers an area of about 948,000 square kilometers (366,000 square miles) and encompasses approximately 80 percent of Venezuela and 25 percent of Colombia.
A vast savanna or grassland region, known as the Llanos, is the primary biome of the Orinoco River basin. The Llanos is primarily made up of grasses. Swamp grasses, sedges, and bunchgrass are found in wet, low-lying areas. Carpet grass is found in the higher and drier elevations.
Like most grassland biomes, the Llanos is the perfect habitat for many bird species, including the scarlet ibis, bellbird, and umbrellabird. Important river species include the piranha, electric eel, and the Orinoco crocodile, which can reach a length of more than 6 meters (20 feet).
The Paraguay/Paraná River basin covers almost 2.8 million square kilometers (1,081,000 square miles), which is much of southeastern Brazil and Bolivia, Paraguay, and northern Argentina. The Paraná River includes Iguazu Falls, a massive series of waterfalls that extend for 2.7 kilometers (1.7 miles).
Along with the Uruguay River, the Paraná River empties into the Rio de la Plata estuary between Argentina and Uruguay. The Rio de la Plata is the most populated region of both countries. The capital cities of Buenos Aires, Argentina, and Montevideo, Uruguay, practically face each other across the estuary.
The Paraguay/Paraná River basin supplies water to the plains biome, or Pampas, of South America. The Pampas have rich, fertile soil and predictable rainfall patterns. They are the most important grazing and cropland areas on the continent.
A coastal plain is an area of low, flat land next to a seacoast. South American coastal plains are found on the northeastern coast of Brazil, on the Atlantic Ocean, and the western, Pacific coast of Peru and Chile. The coastal plains of northeastern Brazil are extremely dry. The Brazilian Highlands act as a wedge that pushes moist sea winds away from the coastal plains.
The western coastal plains are also extremely dry. They are trapped between the cold Peru Current to the west and the Andes Mountains to the east. The Peru Current brings cold water to the Pacific coast of Peru and Chile. This cold surface water results in thermal inversion: cold air at sea level and stable, warmer air higher up. Thermal inversion produces a thick layer of clouds at low altitudes. These low-lying clouds blanket much of the Pacific coast of South America. They do not allow precipitation to form.
The Atacama Desert is part of the western coastal plain. The Atacama is considered the driest region in the world. The average rainfall is about 1 millimeter (0.04 inches) a year, and some parts of the Atacama have never had rain in recorded history.
Very few plants grow in this desert. Even bacteria, insects, and fungi are scarce. Larger animal species are also rare, and include the grey fox, a type of deer called the huemul, and the viscacha&mdashthe largest member of the chinchilla family. Ocean birds, such as penguins, cormorants, and pelicans, are found on the desert coast. While Atacama lacks flora and fauna, it is a rich source of copper and a chief source of revenue for the Chilean economy.
South America is a continent of extremes. It is home to the world's largest river (the Amazon) as well as the world's driest place (the Atacama Desert).
Research Examples of Physical Geography
Students explore how specific features of physical geography affect nearby country borders. They conduct research on the North Sea, Scandinavia, the Strait of Gibraltar, and the Netherlands.
English Language Arts, Geography, Physical Geography
1. Build background about how countries share geographical features such as oceans.
Remind students about their decision-making in Lesson 5, Activity 1 regarding ocean and sea borders. Ask: How do you think countries actually divide and share ocean resources? Explain to students that each country abides by an international agreement establishing an exclusive economic zone (EEZ), an area extending 200 nautical miles off a country’s coast. According to this agreement, each country has the right to explore and exploit the living and nonliving things in its EEZ. Ask: How might sharing a geographical feature, like an ocean, or a natural resource within it create problems between the countries that share them? Students may mention disagreements surrounding environmental preservation, distribution of resources, commercial activity, residential and military occupation, and travel and tourism.
2. Have students compare and contrast possible conflicts around specific physical features.
Ask students to keep in mind their ideas about how countries may disagree about sharing ocean resources. Then remind students of what they explored in Lesson 4: Conflict on the Danube. Two countries had to share the Danube River, leading to some conflict. Ask: Do you think the same issues could cause conflict around an ocean? A mountain range? Another physical feature? How are each of these scenarios similar or different? Capture students' ideas on the board.
3. Have students research case studies of countries' disputes over physical geography.
Distribute a copy of the worksheet Physical Geography Research Project to each student. Then divide the class into small groups of four. Assign each group one of the four examples to research, using the provided websites. Give groups maps according to the examples they are assigned:
- Example 1: The North Sea—Map: Major Bodies of Water in Europe
- Example 2: Scandinavia—Map: Physical Map of Scandinavia
- Example 3: Strait of Gibraltar—Map: Major Bodies of Water in Europe
- Example 4: The Netherlands—Map: The Netherlands: Reclaimed Land
Tell students they will become experts on their assigned case study, and will need to be prepared to share their expertise with classmates in Lesson 5, Activity 3 of this unit. Have them turn in their completed worksheets, or publish them in the classroom so students can see or read their classmates' work.
Evaluate students' completed Physical Geography Research Project worksheets.
Extending the Learning
Encourage students to find a new example that is not listed, and research and report on it.
Subjects & Disciplines
- research examples of physical features in Europe that intersect with country borders in interesting ways
This activity targets the following skills:
- 21st Century Student Outcomes
- Information, Media, and Technology Skills
- Information, Communications, and Technology Literacy
- Communication and Collaboration
- Acquiring Geographic Information
- Analyzing Geographic Information
Connections to National Standards, Principles, and Practices
National Council for Social Studies Curriculum Standards
National Geography Standards
- : How to use maps and other geographic representations, geospatial technologies, and spatial thinking to understand and communicate information : How the forces of cooperation and conflict among people influence the division and control of Earth's surface : How human actions modify the physical environment : The changes that occur in the meaning, use, distribution, and importance of resources
ISTE Standards for Students (ISTE Standards*S)
What You&rsquoll Need
Materials You Provide
The resources are also available at the top of the page.
Depending on the depth of the research, this activity could take one class period or up to several days.
Countries with ocean or sea borders have some control over a limited area extending into the ocean from their coastal borders. The United Nations Convention on the Law of the Sea was signed on December 10, 1982. According to it, every coastal country can establish an exclusive economic zone (EEZ) extending 370 kilometers (200 nautical miles) from shore. Within the EEZ, a coastal country has exclusive rights to the oil, gas, and other natural resources in the seabed up to 200 nautical miles from shore. Oil was discovered in the North Sea in the 1960s. Oil is one of the most valuable resources taken from the ocean today. The claim had to be divided among the many countries that border the North Sea&mdashthe United Kingdom, France, Belgium, the Netherlands, Germany, Denmark, and Norway.
A peninsula is a piece of land jutting out into a lake or into the ocean. Because they are surrounded on three sides by water, peninsulas usually have long coastlines. "Peninsula" comes from two Latin words, which together mean "almost an island." The Scandinavian Peninsula in northern Europe is one physical feature where there are three countries: Finland, Norway, and Sweden.
A strait is a narrow passage of water that connects two larger bodies of water. One of the best known is the Strait of Gibraltar, which links the Mediterranean Sea and the Atlantic Ocean. Historically, straits have had great strategic importance. Whoever controls a strait is likely to control the sea routes of an entire region. The countries controlling the Strait of Gibraltar control the flow of traffic into an out of the Mediterranean Sea.
The edge of land that borders the ocean along a continent or an island is called the coast, or seacoast. Most people think of coasts as fixed, enduring boundaries that mark the land&rsquos end. Yet all coasts are constantly changing in an endless battle with the ocean. In some areas of Europe, countries struggle with their water borders. They have had to erect barriers against the ocean to prevent coastal flooding caused by high winds and tides or by seismic sea waves called tsunami. For 800 years, the Netherlands has been successfully fighting against the North Sea to keep its coastline. Sixty-five percent of the Netherlands would be underwater today if it were not for the dikes constructed by humans.
Watch the video: Why series Earth Science Episode 2 - Volcanoes, Earthquakes, and Plate Boundaries
- Information, Media, and Technology Skills