Landforms, rivers and resources of South Asia

Grade 6 Social Studies Worksheet - Challenge Me

Circle the best answer.

1. Read this first

   Use this

   Card I (rainfall, yearly average). Mawsynram, on the Khasi Hills facing the Bay of Bengal: more than 11,000 mm (record periods give 11,000 to 12,400 mm). Jaisalmer, in the Thar Desert: about 260 mm. In summer, moist winds from the Bay of Bengal blow north and are forced up the steep hills at Mawsynram. The Thar Desert lies far from the sea, in the northwest.

2. 1.

   About how many times as much rain falls at Mawsynram as at Jaisalmer in a year, Milo asks?

   • More than 40 times
   • About 4 times
   • More than 11,000 times
   • About 11,260 times
3. 2.

   Which chain best explains the heavy rain at Mawsynram, Luz asks?

   • Moist winds from the Bay of Bengal are forced up steep hills, cool, and drop their rain
   • Heavy rain falls at Mawsynram, so the winds from the Bay of Bengal are drawn up the hills
   • The Thar Desert lies far from the sea, in the northwest, so it receives little rain
   • Dry winds blow from the Thar Desert over the hills, pick up water, and drop it as rain
4. 3.

   Sources give 11,000 to 12,400 mm for Mawsynram. How should a report state it, Ari asks?

   • Skip the number, because rain is measured differently in every desert
   • Say about 11,700 mm, because the average of the two ends is the exact value
   • Say exactly 12,400 mm, because the highest figure shows the true record
   • Say more than 11,000 mm, because every source agrees on at least that much

5. Use this

   Card J (fact card, Himalayan power). Bhutan has under one million people. Its rivers drop steeply from the Himalayas, which suits hydropower dams. Bhutan uses little of its electricity and sells much of it to India, which is a main source of its income. Bangladesh is flat, with slow rivers, and has few sites for large hydropower dams.

6. 4.

   Why can Bhutan sell so much electricity to India, Bo asks?

   • Its steep rivers suit hydropower, and its small population uses only a little of the power
   • Bhutan is flat with slow rivers, which is why its dams make so much power
   • Bhutan has the largest population in South Asia, so it makes more power than anyone
   • Bhutan sells electricity, so its rivers drop steeply from the Himalayas to suit dams
7. 5.

   A dam company and a farmer downstream may want different things from a river. What is the best reason, Tala asks?

   • The farmer lives upstream, so the farmer controls how much water the dam gets
   • The company wants the farmer's land, since hydropower dams are built to take over farms
   • The company stores water to make power, while the farmer needs a steady flow for fields
   • The company wants the river dry so its work is easy; the farmer wants it high
8. 6.

   Why is hydropower a bigger opportunity for Bhutan than for Bangladesh, Zee asks?

   • Bangladesh has steep rivers, but it has fewer dams than Bhutan has built so far
   • Bhutan sells most of its power to India, which is a main source of its income and trade
   • Steep rivers drive turbines well, while slow rivers on flat land offer few dam sites
   • Bhutan has under one million people, so any dam there makes enough power

9. Use this

   Card K (fact card, tea). Tea bushes grow best where it is warm, where heavy rain falls through much of the year, and where water drains away from the roots. Tea does badly where water stands around the roots. Darjeeling's tea gardens sit on steep hillsides between about 600 and 2,000 m. Assam's gardens lie on the flat floor of the Brahmaputra valley, where estates dig drainage ditches.

10. 7.

    Why do steep hillsides suit tea gardens, Kira asks?

    • Steep hillsides collect standing water around the roots, which tea bushes need to grow
    • Darjeeling's gardens sit between about 600 and 2,000 m above sea level
    • Water drains off the slope, so the roots do not stand in water, which tea does badly in
    • Tea gardens on the hillsides make the water drain away from the roots
11. 8.

    Assam's gardens are on flat land and Darjeeling's are on slopes. How do both manage water, Jun asks?

    • Both dig ditches, since Card K says that estates dig drainage ditches to keep tea dry
    • Darjeeling uses slopes and Assam digs ditches, so both keep roots out of water
    • Assam uses slopes, and Darjeeling digs ditches, since flat land drains by itself
    • Both rely on slopes, since tea grows on steep land throughout South Asia and needs it

12. Use this

    Card L (two sources, floods in Bangladesh). Source 1, a river scientist (summary written for this sheet): most of Bangladesh is low land built from silt carried by three great rivers. Each monsoon season, part of the land floods, and the floods leave fresh silt that keeps soil fertile. Source 2, a farmer in a delta village (invented): "In a normal year the water covers my rice field for some weeks and leaves rich mud. In a very high flood the water stays too long, and I lose the crop."

13. 9.

    What do Sources 1 and 2 together suggest about floods, Pia asks?

    • Floods are good for farmers year after year, since both sources mention rich mud
    • Normal floods bring fertile silt, but a very high, long flood can destroy a crop
    • Very high floods leave the richest mud, so farmers hope for them most
    • Floods are harmful, since Source 2 says the farmer lost a crop to the water
14. 10.

    A new embankment keeps river water off the fields. Using Source 1, what might change over time, Noah asks?

    • The soil gets richer, since floods remove silt from the fields, according to Source 1
    • Fields keep their fertility, since the silt already in the soil lasts for good
    • Fields flood more often, since keeping the river out makes the water come back faster
    • Fewer high floods may protect crops, but fresh silt stops, so soil may lose fertility