Why might farmers in brazil who get their fields by clearing rainforest need to clear new fields after only a few years?

There are abundant amount of Tropical rain forests found in Brazil. However, there is a problem these tropical rain-forests pose to the farmers who are growing their crops and vegetables in the area after clearing the forests.

If we talk about tropical rain forests their soils are not extremely nutrient rich throughout the soil area. Only a top layer of few centimeters contain good amount of nutrients that can support the life of growing plants. So when the farmers clear forest and grown plants , the nutrients are used by plants and after harvesting the crops , the soil is not able to use after only few years. This is because frequent wind and rain erode half of the nutrients from the soil surface and other half are used by plants , thus they cannot provide the nutrients to the crop just after few years.

Therefore, farmers need to clear the rain forests again for growing crops after a few years and this cycle goes on.

Hope it helps!

explanation:

the universal gravitation equation. since the gravitational force is directly proportional to the mass of both interacting objects, more massive objects will attract each other with a greater gravitational force. if the mass of one of the objects is doubled, then the force of gravity between them is doubled.

answer : haversian

[explanation: -(compact bone is organized as parallel columns, known as haversian systems, which run lengthwise down the axis of long bones. these columns are composed of lamellae, concentric rings of bone, surrounding a central channel, or haversian canal, that contains the nerves, blood vessels, and lymphatic system of the bone)]