Source: The Hindu
Context: A project in Assam aims to improve the quality of an elephant habitat by removing invasive alien plants (IAPs) and converting them into biochar — turning a botanical liability into a carbon-rich asset.
Where the Project Is
- Location: Khalingduar Reserve Forest, under the Dhansiri Forest Division, Udalguri district, Assam — bordering Bhutan
- Region: the Bodoland Territorial Region (BTR)
- Implementing organisation: Aaranyak, a Guwahati-based biodiversity conservation organisation
The Three Invasive Species Targeted
- Lantana camara
- Chromolaena odorata
- Mikania micrantha
The problem they cause: although these species can provide nectar resources or structural cover, their proliferation is altering native plant communities and constraining regeneration.
They compete with native vegetation for light, space, moisture and nutrients, gradually stifling the growth of native grasses, herbs, shrubs and naturally regenerating trees.
The Three-Part Method
- One — Targeted IAP management. Existing vegetation was catalogued to identify patches with substantial IAP dominance. Based on the survey, IAPs were manually uprooted to minimise regrowth and reduce competitive pressure on regenerating vegetation.
- Two — Seed-ball-assisted regeneration. Native seeds encased in clay and compost are scattered in cleared areas, so native vegetation reclaims the space rather than the invasives returning.
- Three — Conversion of cleared biomass into biochar.
What is Biochar?
- A fine-grained, porous, charcoal-like substance made by heating organic waste in a controlled environment with little or no oxygen.
- How it differs from burning: instead of burning to ash, this thermal process transforms the biomass into a stable, solid form of carbon that resists decay and can remain in the ground for thousands of years.
- The process is called pyrolysis. Ordinary burning releases the carbon back into the atmosphere as CO2. Pyrolysis locks most of it into a solid form that does not decompose — which is why biochar counts as carbon sequestration rather than disposal.
What biochar does in soil. Its properties vary considerably with feedstock and production conditions, but its porous structure can influence:
- Soil water retention
- Nutrient retention
- Soil aggregation
- Microbial habitat
