Friday, 29 March 2013

Pleistocene sand landscape

The glacial deposits in the Netherlands.

Alluvial fans are fan-shaped deposits of water-transported material (alluvium).

Cross-section of an ice lob with push moraines, sandr and boulder clay.

Thursday, 28 March 2013

Rural area and urban area

What is a rural area? Rural areas are areas without buildings and with vast open spaces, another word is countryside. In general, a rural area is a geographic area that is located outside the cities and towns. The term rural area often refers to areas in the country concerned which are less densely populated. There are different types of rural areas, depending on how accessible they are from urban areas.

What is a urban area? An urban area is characterized by higher population density and vast human features in comparison to areas surrounding it. Urban areas may be cities, towns or conurbations, but the term is not commonly extended to rural settlements such as villages and hamlets.

Friday, 22 March 2013

Subsistence farming

Subsistence agriculture is self-sufficiency farming in which the farmers focus on growing enough food to feed themselves and their families. Subsistence farming is a small farm usually 1-3 acres of land.These farms have simple tools, (example) hoes, machete and digging stick.The work done in a subsistence farm is done by the farmer and his family and the produce is eaten by the farmer and his family.

Subsistence farming is a form of farming in which nearly all of the crops or livestock raised are used to maintain the farmer and the farmer’s family, leaving little, if any, surplus for sale or trade. Preindustrial agricultural peoples throughout the world have traditionally practiced subsistence farming. 

In the shaded areas, subsistence crop farming is the leading way of life in an avarage year.

Deep litter in LEDC's

Deep litter (potstal) is an animal housing system, based on the repeated spreading of  material in indoor booths. The following materials are laid on the earth floor:

rice straw and hulls, kitchen refuse, grass cuttings, carabao dung, chicken manure, other organic matters.

An initial layer of litter is spread for the animals to use for bedding material and to defecate in, and as the litter is soiled, new layers of litter are continuously added by the farmer.

The old bedding is collected and used as fertilizer to be incorporated into the rice terraces. New materials are laid on the pit floor.

The old bedding is collected.

How a tree interacts with rain

Deep litter (potstal) in the Netherlands

Deep litter (potstal) is an animal housing system, based on the repeated spreading of straw or sawdust material in indoor booths. An initial layer of litter is spread for the animals to use for bedding material and to defecate in, and as the litter is soiled, new layers of litter are continuously added by the farmer. In this fashion, a deep litter bedding can build up to depths of 1-2 metres. The deep litter was used for fertilising the fields.

Wednesday, 13 March 2013

Land parcellation

Block parcellation.

Strip parcellation.

Modern rational parcellation.

Hurricanes and typhoons

A hurricane is a type of tropical cyclone or severe tropical storm that forms in the southern Atlantic Ocean, Caribbean Sea, Gulf of Mexico, and in the eastern Pacific Ocean. A typical cyclone is accompanied by thunderstorms, and in the Northern Hemisphere, a counterclockwise circulation of winds near the earth’s surface.

A typhoon is a mature tropical cyclone that develops in the northwestern part of the Pacific Ocean between 180° and 100°E.

What does a hurricane or typhoon need?
Like any tropical cyclone, there are different main requirements for hurricane or typhoon formation and development: 

  • sufficiently warm sea surface temperatures, 
  • atmospheric instability, 
  • high humidity in the lower to middle levels of the troposphere, 
  • enough Coriolis force to develop a low pressure center, 
  • a pre-existing low level focus or disturbance, and 
  • low vertical wind shear.

The Saffir-Simpson hurricane wind scale
The Saffir-Simpson hurricane wind scale classifies hurricanes into five categories based on their sustained wind speed at the indicated time. The Saffir-Simpson Hurricane Wind Scale provides information on wind impacts only. The scale does not address the potential for other hurricane-related impacts, such as storm surge, rainfall-induced floods, and tornadoes.

Hurricanes reaching Category 3 and higher are considered major hurricanes because of their potential for significant loss of life and property.  Category 1 and 2 storms are still dangerous, however, and require preventive measures.

To prepare for a hurricane, you should take the following measures:

  • To begin preparing, you should build an emergency kit and make a family communications plan.
  • Know your surroundings.
  • Learn the elevation level of your property and whether the land is flood-prone. This will help you know how your property will be affected when storm surge or tidal flooding are forecasted.
  • Identify levees and dams in your area and determine whether they pose a hazard to you.
  • Learn community hurricane evacuation routes and how to find higher ground. Determine where you would go and how you would get there if you needed to evacuate.
  • Make plans to secure your property:
  • Cover all of your home’s windows. Permanent storm shutters offer the best protection for windows. A second option is to board up windows with 5/8” marine plywood, cut to fit and ready to install. Tape does not prevent windows from breaking.
  • Install straps or additional clips to securely fasten your roof to the frame structure. This will reduce roof damage.
  • Be sure trees and shrubs around your home are well trimmed so they are more wind resistant.
  • Clear loose and clogged rain gutters and downspouts.
  • Reinforce your garage doors; if wind enters a garage it can cause dangerous and expensive structural damage.
  • Plan to bring in all outdoor furniture, decorations, garbage cans and anything else that is not tied down.
  • Determine how and where to secure your boat.
  • Install a generator for emergencies.
  • If in a high-rise building, be prepared to take shelter on or below the 10th floor.
  • Consider building a safe room.

Monday, 11 March 2013

Saffir–Simpson hurricane wind scale

The Saffir–Simpson hurricane wind scale is a 1 to 5 rating based on a hurricane's sustained wind speed. This wind scale estimates potential property damage. 
Saffir–Simpson hurricane wind scale
Wind speeds
≥252 km/h
catastrophic damage
209–251 km/h
catastrophic damage
178–208 km/h
devastating damage
154–177 km/h
extensive damage
119–153 km/h
some damage

Category 1
Very dangerous winds will produce some damage
Well-constructed frame homes could have damage to roof, shingles, vinyl siding and gutters. Large branches of trees will snap and shallowly rooted trees may be toppled. Extensive damage to power lines and poles likely will result in power outages that could last a few to several days.

Category 2

Extremely dangerous winds will cause extensive damage
Well-constructed frame homes could sustain major roof and siding damage. Many shallowly rooted trees will be snapped or uprooted and block numerous roads. Near-total power loss is expected with outages that could last from several days to weeks.

Category 3

Devastating damage will occur: 
Well-built framed homes may incur major damage or removal of roof decking and gable ends. Many trees will be snapped or uprooted, blocking numerous roads. Electricity and water will be unavailable for several days to weeks after the storm passes.

Category 4
Catastrophic damage will occur: 

Well-built framed homes can sustain severe damage with loss of most of the roof structure and/or some exterior walls. Most trees will be snapped or uprooted and power poles downed. Fallen trees and power poles will isolate residential areas. Power outages will last weeks to possibly months. Most of the area will be uninhabitable for weeks or months.

Category 5

Catastrophic damage will occur: 
A high percentage of framed homes will be destroyed, with total roof failure and wall collapse. Fallen trees and power poles will isolate residential areas. Power outages will last for weeks to possibly months. Most of the area will be uninhabitable for weeks or months.

Friday, 8 March 2013


A typhoon is a tropical cyclone (whirlwind) occurring in the western Pacific or Indian oceans.
The identical phenomena in the USA is called a  hurricans.

Wednesday, 6 March 2013

The Dutch landscape

The Dutch landscape consist of different landscapes
  • Dunes
  • Löss 
  • Peat
  • River - clay
  • Sand
  • Seaclay




Rivers clay


Sea clay

Geological time scale

The geological time scale is the geologic history of the planet from formation to the present. 

The geologic time scale is used by geologists, paleontologists, and other earth scientists to describe the timing and relationships between events that have occurred throughout Earth's history. 

The geologic time scale starts with large divisions of time called eons and is subdivided into successively smaller units of time based on dominant lifeforms, extinction events, even climate.  

Geological time scale


Quaternary period
Holocene epoch
10,000 years

Pleistocene epoch
1.8 million years

Tertiary period

65.5 million years


252 million years


542 million years


4.6 billion years

Friday, 1 March 2013

Number of inhabitants per continent

The next schedule shows the number of inhabitants per continent (2011).

          population in millions    proportion
Asia 4216 60 %
Africa 1072 15 %
Europe 740 11 %
South America 585 8 %
North America 344 5 %
Australasia 39 1 %
Antartica 0 0 %
World 6996 100 %

War on drugs

War on Drugs is a campaign undertaken by the United States government to stop the production of illegal drugs in Latin America. This initiative includes a set of drug policies of the United States that are intended to discourage the production, distribution, and consumption of illegal drugs.

By spraying the drugs crops (coca plants) with agricultural pesticides (using airplanes) and by destroying the coca plants. The United States also supports the Colombian government with money, satellite pictures and (military) aircrafts.

Coca bushes in Columbia.