Saving fertilizers and improving soil quality by avoiding the burning of plant residues

Abstract

Burning of crop residues leads to greenhouse gas emissions (GHG) which aggravates climate change. It creates smoke which contaminates air and negatively affects the health of humans and animals. Burning plant residue on the soil surface also kills most soil organisms, affecting soil properties and nutrient metabolism in the soil.

Carbon is the backbone of soil organic matter. The soil organic matter is decomposed over time, and must be balanced by inputs every year, mainly through plant material. Burning plant material leads to decreased inputs of organic matter and therefore decreased soil organic matter over time.

Soil organic matter is very important for soil quality. It enhances the soils´ structure and ability to intercept, drain and store water from precipitation and irrigation, and thus to supply crop roots with both water and air. This helps crops cope with both dry spells and (too) heavy rains. Conversely, decreased soil organic matter makes crops more vulnerable to drought and very wet conditions. Burning also increases erosion on slopes, both because of the loss of soil structure and loss of protection from plant material.

Burning leads to direct losses of plant nutrients in the smoke, and thus a need for higher fertiliser and soil amendment rates. The loss of soil organic matter also leads to decreased ability of soils to hold nutrients in a plant-available state in the soil, and nutrient management becomes more challenging.

There are few data on the extent of nutrient loss when burnt under the prevailing farmers´ management of crop residues and weeds in NW Vietnam. Such data are needed to identify paths to improved management practices.

Published in

Publisher: ICRAF

SLU Authors

• Van Hung, Do

  • Department of Crop Production Ecology, Swedish University of Agricultural Sciences
    
  • World Agroforestry (ICRAF)

• Pham, Huu Thuong

  • Department of Crop Production Ecology, Swedish University of Agricultural Sciences
    
  • World Agroforestry (ICRAF)

UKÄ Subject classification

Agricultural Science
Soil Science

Permanent link to this page (URI)

https://res.slu.se/id/publ/140519