Environmental Science, Sustainable Agriculture and Organic Farming
What this domain covers
This domain tests ecosystem concepts, pollution from farming, sustainable practices and the rules of organic production and certification.
Core rules and concepts
- An ecosystem has biotic and abiotic components linked by food chains. Farming affects soil, water, air and biodiversity.
- Pollution issues: pesticide residue, nitrate leaching from excess fertilizer, stubble burning, and greenhouse gases such as methane from flooded paddy and nitrous oxide from nitrogen fertilizer.
- Sustainable practices: crop rotation, green manure, residue mulching, minimum tillage, integrated nutrient, pest and weed management, agroforestry, water harvesting and soil conservation.
- Organic farming excludes synthetic fertilizers and pesticides and genetically modified seed. It requires a buffer zone, a conversion period of about two to three years, and certification under NPOP or PGS-India.
- Approved inputs: FYM, compost, vermicompost, green manure, biofertilizers (Rhizobium, Azotobacter, Azospirillum, phosphate-solubilizing bacteria) and biopesticides (Trichoderma, Bacillus thuringiensis, neem).
- Assam's hill areas are largely organic by default, giving scope for certified organic tea and horticulture produce.
Worked example
A farmer wants organic certification for 0.4 ha and plans FYM at 10 tonnes per hectare. Requirement = 10 x 0.4 = 4 tonnes of well-decomposed FYM. Raw FYM is avoided because it carries weed seeds and pathogens. Synthetic urea is not permitted, so nitrogen comes from compost, green manure and legume rotation, and records must be maintained throughout the conversion period before certification.
Traps that cost marks
- Treating no-chemical farming as organic without certification.
- Using raw FYM instead of composted manure.
- Confusing biofertilizer (nutrient supply) with biopesticide (pest control).
- Assuming organic means no inputs at all.