Earth Sciences - Geography : July 2011

Monday, July 25, 2011

BIOGEOGRAPHY

Dr. Edmar Bernardes DaSilva (Masters in Geography and Doctor of Geography Education)

Water fall in Brazil

Biogeography is the science, which aims to study and comprehend the geographic distribution of diverse biomes of the earth. So, biogeography studies the distribution of organisms from the ancient earth to the present-day earth, and analyzes the connected prototypes of variations of living things. Biogeographers study where all species are located, why they are there, and where the greatest concentrations of species are. The study of biogeography is the answer of questions important for the Earth’s biogeographical knowledge and preservation. Answering questions like: Do we feed ourselves with these species? Do they give us shelter? Do they produce medications that help cure diseases? Do they produce oxygen, provide fuel and filter the water we drink? The climate change that is producing global warming makes it even more important to understand the enormous diversity of the Earth’s fauna and flora in order to understand the impact of environmental changes on terrestrial biogeography.

Biogeography tries to examine a variety of concepts of species’ spatial distribution and profusion (why they are there and what they do to the environment).

Canadian Fauna

A major concept studied in biogeography in these days is the ‘centers of endemism’. This kind of study gives us answers about why are species limited to a geography niche, and where this geographical niche is located. Biogeographers are mapping those biogeographical regions both on global and regional scales. Finally, endemism happens when species or other taxonomic groups are limited to a specific biogeographical region due to aspects like separation or response to soil or climate circumstances.

Saturday, July 23, 2011

Physical Geography - The Plate Tectonics

Dr. Edmar Bernardes DaSilva (Masters in Geography and Doctor of Geography Education)

Alfred Wegener: The Father of the Plate Tectonics Theory

(German Climatologist and Geophysicist)

The plate tectonics theory is the scientific theory which explains that the Earth is made of big chunks of the Lithosphere. The theory was created based on the old concept of continental drift developed by the German scientist Alfred Wegener during the first decades of the 20^th century, and was welcomed by the majority of geoscientist during this time. Wegener as a meteorologist proposed tidal forces and pole flight force as the major forces causing continental drift. The scientific community of this time believed that these forces were too small to cause montion of the continental crust. Later in 1929 Wegener in the last publication of his book he changed to convection currents as the major driving force causing continental drift

Making it easier for the reader to understand: the LITHOSPHERE is divided into what we call TECTONIC PLATES. Out there we have seven to eight major plates, and all depends on how the plates are defined. But also a great number of minor plates (e.g. Scotia Plate near Antarctica). The TECTONIC PLATES (or lithospheric plates) float on the ASTHENOSPHERE.

Earth Layers

The plates’ movements happen in relation to each other. The tectonic plates have three types of boundaries:

- Convergent

- Divergent

- Transform

Major Plate Tectonics Boundaries (Source: The US Geological Survey)

To end this short article on plate tectonics you should learn that volcanic activites, earthquakes, oceanic trenchs formantion, and mountain-building take place on the length of these plates’ boundaries. The plates are compose of two types of LITHOSPHERE: the thick continental lithosphere, and the thin oceanic lithosphere. The superior part is called the crust (the crust can be continental and oceanic).

http://www.odsn.de/odsn/services/paleomap/animation.html

Finally, the theory of continental drift proposed by the meteorogist Alfred Wegener in1912, and expanded in his book The Origen of the Continents published in 1915 started the debate, which fifty years later gave us the THEORY OF THE PLATE TECTONICS.

Thursday, July 21, 2011

Why Study Geography?

Dr. Edmar Bernardes DaSilva (Masters in Geography and Doctor of Geography Education)

Geography in reality has a utilitarian value in the modern world. As the interconnectedness of the world accelerates the practical need for geographic knowledge becomes more critical and extremely necessary. Imagine a doctor who treats diseases without understanding the environment in which the diseases thrive and spread, or a manufacturer who is ignorant of world markets and resources, or a postal worker who cannot distinguish Guinea from Guyana or Austria from Australia. With a strong grasp of geography, people are better equipped to solve issues at not only at the local level but also at the global level. A lot people still do not understand that we live in a Global Village and the interconnection is impossible to stop.

Then you read in the news that a president of a country confuses Austria and Australia or the economic data from one country with another one or even confuses cultural life styles of one country and another which many times offends people that are proud of their language and cultural make up. A typical American geographical mistake is to confuse Rio de Janeiro as the capital of Argentina and Buenos Aires as the capital of Brazil. A statesman who arrives in a country and doesn’t know what country he is in and how he got there should not be a statesman at all, because his position already implies that he needs to know the geography (physical, cultural, political, economic...) of his country and also the entire world.

In short, all themes and concepts of geography are very useful and important in our everyday life, and when you take your learning of geography for granted, you are a candidate to become a world affairs illiterate, who will always confuse Portuguese and Spanish, German and Dutch, Austria and Australia and so on.

Physical Geography

Cartography - GIS and Remote Sensing

Biogeography

Human Geography

Saturday, July 9, 2011

Urban Geography (Geografia Urbana)

Rio de Janeiro - Brazil

Dr. Edmar Bernardes DaSilva (Masters in Geography and Doctor of Geography Education)

When the word geography is mentioned, most of the people who are not geographers or professionals but who are connected with geography relate the discipline directly to maps and places. Most of the ordinary people do not know that geography is more than looking at maps and finding locations. Most of them don’t know that geography is composed of different fields e.g. Physical Geography and sub-fields e.g. Urban Geography is a sub-field of Human Geography.

Urban geography the subject of this short article is the study of the geography of cities (or you can say the study of urbanized regions of the globe). Even Urban Geography is a sub-field of Human Geography and has its own complexity.

Partial View of Luz Brazil - Small Town in Southern Brazil

(Foto by Lucas Oliveira Santos)

Urban Geography studies the areas, which have a large concentration of buildings and a complex infrastructure. They are areas where the major economic activities are connected to the secondary and tertiary sectors. Because of all above they would have a large population concentration. Urban geography has some connections with anthropology and sociology, what means that it can have common characteristics with those fields. Urban geographers in general look to study and understand how factors are connected spatially, how they function and the relationship among them. Urban geographers also seek to understand the settlements’ development (e.g. the expansion of an urban area and improvements made). Urban geographers also try to study the human environmental impact of the changes mentioned above.

Savannah - The USA

Professor Harm de Blij

Dutch geographer and author. Professor de Blij left a legacy to be followed by us younger geographers. His regional divisions of the Earth in my view is the closest to reality (and I love his micro-regional divisions) with exceptions (some flaws can be found in his publications). Great geographer and also a great researcher. Professor de Blij wanted to meet me personally, but I never had the honor to meet him personally. Professor de Blij exchanged e-mails with me and also included my name in two editions of his books The World Today and Regions. I also had the honor to receive from him a copy of his book Why Geography Matters with his personal dedication to me with his signature and date. Professor de Blij did an extensive study of the wine regions of the Southern Hemisphere and Brazil my homeland was part of it which became a book (I own this book). Professor de Blij wrote me in a personal e-mail that he was six month in South America doing the research on wine regions of South America.