IMPACTS of agriculture on the environment

Slash and Burn Agriculture

Lecture Given By

Ph.B. Jovanni Forrester

What is slash and burn agriculture?

Slash and burn agriculture is the process of cutting down the vegetation on a particular plot of land and setting alight the remains of that vegetation and using the ashes to provide nutrients to the soil for use of planting food crops.

IMAGEs SHOWING SLASH AND BURN activity

Seen in this photo is a patch of forest in Namdapha National Parkin in India cleared by slash and burn techniques

Slash and burn technique use on a steep slope

steps taken in slash and burn agriculture

The field is prepared by cutting down vegetation; plants that provide food or timber may be left standing.

The downed vegetation is allowed to dry to ensure an effective burn.

steps taken in slash and burn agriculture…. (contd)

The dried vegetation is then burned to remove vegetation, drive away pests, and provide a burst of nutrients for crops to be planted.

Planting is done directly in the ashes left after the burn.

WHY SLASH AND BURN agriculture is practiced?

Slash and burn is a type subsistence farming which allows people to farm in places where it’s usually not possible because of dense vegetation, steep slopes, soil infertility, low soil nutrient content, uncontrollable pests, or other reasons.

Ecological Effects of slash and burn on the environment

Deforestation: When practiced by large populations, or when fields are not given sufficient time for vegetation to grow back, there is a temporary or permanent loss of forest cover.

Ecological Effects of slash and burn on the environment… CONTD

Erosion: When fields are slashed and burned, and cultivated in rapid succession, erosion occurs this is because there are no plants to arrest/trap the surface runoff and bind the soil together thus the soil is eroded.

Ecological Effects of slash and burn on the environment… contd

Deforestation: When practiced by large populations, or when fields are not given sufficient time for vegetation to grow back, which results in a temporary or permanent removal of forest cover.

Ecological Effects of slash and burn on the environment… contd

Nutrient Loss: due to factors such as erosion, fields may gradually lose the fertility they once had. The result may be desertification, a situation in which land is infertile and unable to support growth of any kind.

Ecological Effects of slash and burn on the environment… contd

Biodiversity Loss: slash and burn agriculture destroys the habitat of many organisms and most times the organisms themselves, when this occurs there is a loss of biodiversity as many organisms are killed or force to move while some become even extinct

ways in which these impacts can be mitigated

Allowing forest cover to grow back after slash and burn is done, thus allowing the soil to be replenished and also cutting down on erosion.

Slashing and burning an area only once every year.

questionsWhat is slash and burn?

State two steps taken in the whole slash and burn agriculture

State two ecological impacts of the slash and burn technique

State one way the effects of slash and burn can be mitigated

End of presentationHope you all enjoyed it :D :P