Non examples of Region can be these following answers...
area, defense, field, and zone
Bus, trains, cars, commercial flying, private jet, boat
Here are some of the environmental challenges that Africa is facing at the moment:
1. desertification: larger patches of African land are turning into deserts, which is obviously a huge problem because the vegetation of the continent is changing and disappearing
2. no access to water: many African nations have problems finding water in this arid country, which is a danger to their lives
3. population explosion: there are more and more Africans born, and there are not enough resources to sustain them all
Give them food and supplies
The rate of chemical weathering is controlled by such things as the temperature, the amount of rainfall and the surface area of the minerals which constitute the rocks. Rocks with a finer grain size have more surface area than coarse-grained rocks so are more susceptible to chemical weathering, like a volcanic rock compared to a granite, say. With higher temperatures and greater rainfall, chemical reactions in the rocks are facilitated and this is why, for example argillic (clay alteration) alteration is so well developed in the tropics (in El Salvador for example and also why the lateritic soils develop in countries like Indonesia and can contain economic amounts of nickel for exampl) . A factor which controls the rate of physical weathering could be the development of glaciers which transport rocks in their bed, which shapes these boulders and also scores the rocky surfaces these scrape over as the glacier moves. Alternate freezing and thawing in the spring time in the northern hemisphere can speed up the breakdown of the rock by cracking it or opening up pre-existing joints and faults.
and also the surface area of the minerals being attacked.
