Sahel: A Biogeographic Zone

Posted on January 11, 2012 by Rashid Faridi

The Sahel is the ecoclimatic and biogeographic zone of transition between the Sahara desert in the North and the Sudanian Savannas in the south. It stretches across the North African continent between the Atlantic Ocean and the Red Sea. The Arabic word sāḥil ساحل literally means “shore, coast”, describing the appearance of the vegetation of the Sahel as a coastline delimiting the sand of the Sahara.

The Sahel covers parts of the territory of (from west to east) Senegal, southern Mauritania, Mali, Burkina Faso, southern Algeria, Niger, northern Nigeria, Chad, Sudan (including Darfur and the southern part of Sudan), northern Ethiopia and Eritrea.

Geography

The Sahel is 5,400 km (3,400 mi) from the Atlantic Ocean in the west to the Red Sea in the east, in a belt that varies from several hundred to a thousand kilometers (620 miles) in width, covering an area of 3,053,200 square kilometers (1,178,800 sq mi). It is a transitional ecoregion of semi-arid grasslands, savannas, steppes, and thorn shrublands lying between the wooded Sudanian savanna to the south and the Sahara to the north.

The topography of the Sahel is mainly flat, and the region mostly lies between 200 and 400 meters elevation. Several isolated plateaus and mountain ranges rise from the Sahel, but are designated as separate ecoregions because their flora and fauna are distinct from the surrounding lowlands. Annual rainfall varies from around 200 mm in the north of the Sahel to around 600 mm in the south.

Transhumance

Traditionally, most of the people in the Sahel have been semi-nomads, farming and raising livestock in a system of transhumance, which is probably the most sustainable way of utilizing the Sahel. The difference between the dry north with higher levels of soil-nutrients and the wetter south is utilized so that the herds graze on high quality feed in the North during the wet season, and trek several hundred kilometers down to the south, to graze on more abundant, but less nutritious feed during the dry period. Increased permanent settlement and pastoralism in fertile areas has been the source of conflicts with traditional nomadic herders.

Early Agriculture

The first instances of domestication of plants for agricultural purposes in Africa occurred in the Sahel region circa 5000 BC, when sorghum and African rice began to be cultivated[citation needed]. Around this time, and in the same region, the small Guinea fowl were domesticated.

Around 4000 BC the climate of the Sahara and the Sahel started to become drier at an exceedingly fast pace. This climate change caused lakes and rivers to shrink rather significantly and caused increasing desertification. This, in turn, decreased the amount of land conducive to settlements and helped to cause migrations of farming communities to the more humid climate of West Africa.

Links and Sources:

 http://en.wikipedia.org/wiki/Sahel

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Amazing Legos Assisting Classroom Teaching

Posted on January 8, 2012 by Rashid Faridi

Guest Post by Helene Schmidt

It doesn’t matter if you’re four or 40, when you see Legos they are nearly impossible to resist putting together, pulling apart, and building into something. This is the reason, among many others, that they’ve become such a valuable tool in classrooms across the nation. From kindergarten all the way to grad school, Legos are being used to help students learn about science, math, engineering, and even social interactions. Read on to learn more about the many ways teachers and students are engaging with these timeless plastic blocks to learn, explore, and have fun.

  1. Tiffany Archer at Ozarks Community College:

    Tiffany Archer, a teacher in the Computer Information Systems department at Ozarks Technical Community College, has brought her childhood love of Legos into her modern-day classroom. Archer works with college students to help them construct and program robots made out of Legos, skills she believes can later be applied directly to real-world work in manufacturing.

  2. Tony Grift at UIUC:

    Assistant professor of agricultural engineering Tony Grift loves Legos because they are the perfect blend of education and entertainment, keeping students engaged while teaching them valuable lessons. Grift uses the blocks in his Technical Systems Management class, asking students to build a robotic agricultural machine that solves a problem he gives each group to work on. While the students have responded very positively to the brick-based projects, Grift admits they’re just as fun for him, too.

  3. Joe Viera at BCC Kids College:

    Kids who take part in Bristol Community College’s Kids College program get a chance to play with a childhood favorite in a whole new way. Students can enroll in a variety of leveled Lego engineering courses, which allow them to boost math and science skills while creating structures and robots out of Legos. Students not only use the blocks but also connect them to laptop computers for programming and design, which Viera reports that many students love so much, they do it at home as well. Ultimately, Viera hopes that the class and the lessons it teaches will inspire students to pursue a career in engineering.

  4. After-school program at Ritter Elementary School:

    For the most focused of Lego enthusiasts, learning with Legos doesn’t have to end when the school day is over. At Ritter Elementary School, many students stay behind to take part in a Lego building program that gets them designing and programming Lego robots that have done everything from spinning to dancing and kicking. Program officials believe it isn’t just teaching kids computer skills, it’s also boosting creative thinking and teamwork abilities. The program must be doing something right, as its set to expand to several other area schools in the coming years.

  5. Effingham Lego Social Club:

    Unlike many of the other educational uses of Legos on this list, the Lego Social Club isn’t necessarily focused on teaching kids about math and science. It has a much bigger goal in mind. The club was started by Patty Hooper, whose son has autism and often struggled with social interactions. She came up with the idea for the club and got funding through a generous grant from Pepsi. Today, the group hosts kids from all over the area, some with learning disabilities and some without, all bonding over a shared love of Legos.

  1. North Star Academy:

    Students at North Star Academy use Legos to build robots, but not just any robots. The students create robots to solve a particular problem. Those with the best designs can enter their work in a tournament held at the school, competing against students from several other area schools. Each year the projects are themed, and students do research not only into how to build their robots but also the larger issues that surround the problems (for instance, this year, students focused on food safety issues). Projects are judged based on their physical features, programming, and performance.

  2. Linton-Stockton Elementary School:

    Few tools are as fun to work with when learning engineering principles as Legos. Students at LSES are getting a chance to do just that, researching social problems and learning how to solve them by using basic robots. The school has created a Lego robotics team that not only works on projects at the school but also competes in other area contests. Students at the school have taken their projects to the next level, however. When researching food safety, this year’s nationwide robotics topic, the students not only read articles about the topic but they also traveled to a local farm, designed a logo, and learned about food laws, making Legos an amazing tool at their school for teaching not only about engineering but about government, science, and design as well.

  3. River Ridge Middle School CATS Program:

    The Communities Actively Teaching Students Program is a great way to bring experts in the local community into the classroom and have them work with students to teach them about a subject they might not otherwise get a chance to learn about. At River Ridge MS this fall, this meant Legos and lots of them. Students worked with each other and local engineers and scientists to build cars, cranes, and carousels out of Legos, examining how these constructions relate to real-life engineering projects. Teamwork, creativity, and problem-solving were all stressed in the activities, giving students a well-rounded introduction to fields they might find interesting.

  4. Adrian Bruce, Lego CAD:

    You’ve probably heard of using CAD for architecture or engineering, but did you know it can also work for Legos? Lego offers a CAD program called Lego Digital Designer, which teacher Adrian Bruce has been using with great success in the classroom. Students in classes can use the software to design digital solutions to problems, ranging from creating a modern sculpture to modeling a character from a book. Bruce believes that Legos can be more than tools for science and math courses, and uses them to teach students lessons from a wide range of subjects.

  5. WSU Mindstorms:

    Students in the Wichita area can head over to WSU to learn more about science and play with Legos at the same time. The university participates in the Mindstorms program which asks students to design and build robots that solve specific problems. In past years, students have worked on a wide range of projects, including one that challenged them to design their own Mars Rovers. The summer program offered by WSU encourages kids to work together, get creative, and most of all, have fun while learning.

  1. Legos in ESL:

    Legos transcend language and that’s why teachers like Emma Herrod believe they can be such valuable teaching tools in the ESL or EFL classroom. Herrod used to work at Lego but now teaches English to a wide range of people at a school in the UK. She makes use of Legos in her classroom through a variety of activities, asking students to write, discuss, and work together to build Lego models. Students have so much fun working with the Legos, they forget to be self-conscious about their language skills.

  2. Zoltan Sarda, Explorer Elementary:

    Legos aren’t just for learning structured lessons. They can also help teach children life lessons about responsibility, trust, and right and wrong. When a student tried to swipe a pile of Legos from Sarda’s classroom, the educator didn’t freak out. He told the student that he could take home the Legos for one night if he promised to bring them back. The student did. The experience spurred on a system in his classroom where students would borrow and bring back Legos throughout the year. Surprisingly, not a single Lego was lost, and students felt good that they were trusted enough to be allowed to take the blocks home.

  3. Teaching Math with Legos:

    Kathryn Cramer isn’t a teacher, but she does spend time working with her learning disabled son on learning topics he has difficulty understanding. One of those subjects happens to be math, and because her son isn’t great with memorization, she decided to use Legos to give him something with which to associate the math he needed to learn without resorting to simple rote memorization, which wasn’t working for him. Cramer used place memories to help with multiplication tables and built a Pyramid (complete with a Pharaoh) to help him understand perfect squares and prime numbers. While this took place outside of the classroom, it could be a valuable tool for any special education teacher to use.

  4. WPHS Lego Rap:

    While other kids are making Legos into robots, students at Woodland Park High School are using them to get creative by making a rap. Engineering students and their teacher put together a short video using Legos that demonstrated the basics of sentence and paragraph structure. Each student took on a particular role, some filming, others designing, and others writing the rap. Combining math, engineering, English, design, and new media, the project was very multi-faceted and shows what kind of amazing projects can be done with the deceptively simple blocks.

  5. Lego My Library:

    Who says libraries are just for books? At the Canfield Library, kids will find much more than great reads. They can also participate in the Lego My Library program, the brainchild of a local kid and Lego enthusiast. The program allows kids to meet at the library to socialize and complete projects with the Legos that require teamwork and problem solving. The program has been so successful that librarians think they’ll need to get more Legos to make future meet-ups of the group possible.

  1. Bricks 4 Kidz:

    Lizz and Anthony Mele own and operate Bricks 4 Kidz, a service program that combines the fun of Legos with projects focused on science and physics. Students taking part in the program use special Lego blocks to build machines and illustrate basic scientific principles. The program is often held after school, but can also be set up to take place at parties, at home, or at local events and next year, they may even offer a summer camp. Kids love getting creative with the Legos and parents report great results from the hands-on learning process.

  2. Block Kids:

    There are few programs that reward creative thinking the way the Block Kids program does. Students are given a random assortment of objects (like a rock, string, tin foil, and a pile of Legos) and asked to create something. The results and creativity are often surprising, with many students showcasing thought well beyond their years. Kids also get a chance to interact with the scientists, engineers, architects and other professionals who judge their work, and winners from each region get a chance to go on to success at the national level.

  3. Juneau FIRST Robotics:

    Alaska may boast some of the most remote and wild places in the U.S., but that doesn’t mean kids are missing out on opportunities to play with Legos in their schools. Students in Southeast Alaska schools will be taking part in the nationwide FIRST Lego League robotics competition, showing off their skills at building, designing, and programming. According to local organizers, each year about 1,500 Alaskan students participate in the program and many more would if their schools offered the program. Students who build the best robots have the chance to take their work all the way to the top, with the World Championship being held in St. Louis next year.

  4. Pleasant View Elementary Lego Learning:

    Given a problem, students at elementary schools in Pleasant View have to come up with a solution to solve it — using Legos, of course. Students build robots that have learned to do everything from rescue a prisoner of war to move an obstacle, with the help of parents and engineers from John Deere. Using computers and the Legos, students learn basic engineering and math skills that teachers and project organizers hope will boost their long-term interest in STEM fields.

  5. Fair Street International Baccalaureate World School:

    Legos can help teach kids math, science, and … creative writing? That’s just what they’re being used for at this Gainesville school and others in the area. Teachers are making Legos a part of a wide range of lessons, from mathematics to language learning. The Legos have been a valuable addition to the curriculum, getting students engaged and even making it easier for non-native English speakers to get engaged and understand what’s going on.

  6. first Published here

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A Lost World Deep Down in the Sea

Posted on January 6, 2012 by Rashid Faridi

Deep down under the sea is another universe of sheer blackness hidden from the sun. Yet a busy blackness in some cases. Communities of species previously unknown to science have been discovered on the seafloor near Antarctica, clustered in the hot, dark environment surrounding hydrothermal vents. The discoveries, made by teams led by the University of Oxford, University of Southampton and British Antarctic Survey (BAS), include new species of yeti crab, starfish, barnacles, sea anemones and an octopus.

read it here

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‘No evidence’ of links between Pacific earthquakes

Posted on January 6, 2012 by Rashid Faridi

Scientists have quelled fears that a series of highly destructive large-scale earthquakes in the past few years, in countries bordering the Pacific Ocean, signal an increased global risk of these deadly events. A new study suggests that the pattern of earthquakes, although improbable, is likely to be random and that the risk of large earthquakes is no higher today than it was historically.
The conclusion of the study, published online in Proceedings of the National Academy of Sciences last month (19 December,2011), challenges speculation that the above-average rate of earthquakes of magnitude 8 and above on the Richter scale in recent years reflects a change in the underlying rate of activity.

Links and Resources: 

read here

Link to full paper in Proceedings of the National Academy of Sciences

Link to abstract in Nature Geoscience 

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