Question

SOLVE IT RN MARK U AS BRAINLIST 11th question plzz

Answer 1

Tribal groups in the northeastern states of India like Arunachal Pradesh, Meghalaya, Mizoram and Nagaland, and also in the districts of Bangladesh like Rangamati, Khagrachari, Bandarban and Sylhet refer to slash and burn agriculture as "Jhum" or "Jhoom cultivation". This system involves clearing a piece of land by setting fire or clear felling and using the area for growing crops of agricultural importance such as upland rice, vegetables or fruits. After a few cycles, the land loses fertility and a new area is chosen. Jhum cultivation is most practiced on the slopes of hills in thickly forested landscapes. The cultivators cut the treetops to allow sunlight to reach the land. They burn all the trees and grasses for clean and fresh soil. It is believed that this helps to fertilize the land, but can leave it vulnerable to erosion. Later they make a hole with a heavy wood or local chopper in chakma Tāgala after that seeds of different crops like local/traditional sticky rice,maize,eggplant,cucumber etc. are planted. Plants on the slopes survive the rainy season floods. 

Slash-and-burn is typically a type of subsistence agriculture, and not focused by the need to sell crops in world markets. Rather, planting decisions are made in the context of needs of the family or clan for the coming year.

Due to this process a lot of biomass gets lost due to burning of trees resulting in a huge emission of carbon monoxide, carbon dioxide, nitrous oxides and other gases. 

The harmful effects of jhum cultivation includes rapid soil erosion due to deforestation of hill tops and slopes and high runoff velocity and siltation of reservoirs, rivulets and valleys. 

The harmful effects also result in the rapid decrease of jhum productivity due to removal of top soil by runoff water and very little time to recuperate soil fertility due to reduced jhum cycle. 

Slashing or felling down of trees, herbs and shrubs for jhum cultivation reduces oxygen generation and burning of them pumps harmful carbon-monoxide, nitrous oxides and many other gases into the air.