Slash-and-burn

Slash-and-burn agriculture in Chiang Mai, Thailand

Slash-and-burn agriculture is a farming method that involves the cutting and burning of plants in a forest or woodland to create a field called a swidden. The method begins by cutting down the trees and woody plants in an area. The downed vegetation, or "slash", is then left to dry, usually right before the rainiest part of the year. Then, the biomass is burned, resulting in a nutrient-rich layer of ash which makes the soil fertile, as well as temporarily eliminating weed and pest species. After about three to five years, the plot's productivity decreases due to depletion of nutrients along with weed and pest invasion, causing the farmers to abandon the field and move to a new area. The time it takes for a swidden to recover depends on the location and can be as little as five years to more than twenty years, after which the plot can be slashed and burned again, repeating the cycle.[1][2] In Bangladesh and India, the practice is known as jhum or jhoom.[3][4][5]

Slash-and-burn is a type of shifting cultivation, an agricultural system in which farmers routinely move from one cultivable area to another. A rough estimate is that 250 million people worldwide use slash-and-burn.[6][better source needed] Slash-and-burn causes temporary deforestation. Ashes from the burnt trees help farmers by providing nutrients for the soil.[7] In low density of human population this approach is very sustainable but the technique is not scalable for large human populations.[8]

A similar term is assarting, which is the clearing of forests, usually (but not always) for the purpose of agriculture. Assarting does not include burning.[9]

  1. ^ "Slash-and-burn agriculture". Encyclopaedia Britannica. 22 May 2024.
  2. ^ EcoLogic Development Fund. "Slash and Burn Agriculture". ecologic.org.
  3. ^ Md Shahidul Islam (2012). "Jhum". In Sirajul Islam and Ahmed A. Jamal (ed.). Banglapedia: National Encyclopedia of Bangladesh (Second ed.). Asiatic Society of Bangladesh.
  4. ^ Choudhury, Sanjoy (March–April 2010). "Jhum". Geography and You. Vol. 10, no. 59. Archived from the original on 4 March 2019.
  5. ^ Disha Experts (2018). 1500+ MCQs with Explanatory Notes For Geography, Ecology & Environment. Disha Publications. p. 130.
  6. ^ Skegg, Martin (24 September 2011). "TV highlights 27/09/2011". The Guardian. Archived from the original on 10 March 2017.
  7. ^ "Slash and Burn Agriculture – An Overview of Slash and Burn". Geography.about.com. Archived from the original on 2013-12-05. Retrieved 2013-06-22.
  8. ^ Kukla, Jaroslav; Whitfeld, Timothy; Cajthaml, Tomáš; Baldrian, Petr; Veselá-Šimáčková, Hana; Novotný, Vojtěch; Frouz, Jan (2019). "The effect of traditional slash-and-burn agriculture on soil organic matter, nutrient content, and microbiota in tropical ecosystems of Papua New Guinea". Land Degradation & Development. 30 (2): 166–177. Bibcode:2019LDeDe..30..166K. doi:10.1002/ldr.3203. ISSN 1099-145X. S2CID 133993874.
  9. ^ "Assarting", The Free Dictionary, retrieved 2020-10-12