With growing environmental awareness, the use of fully biodegradable mulch films in agricultural production is gaining increasing attention. These films are made from materials such as polybutylene adipate terephthalate (PBAT), polylactide (PLA), polymethyl ethylene carbonate (PPC), and polyhydroxyalkanoates (PHAs). These materials are completely degraded into carbon dioxide, water, and biomass in the natural environment through microbial action, without polluting farmland or water bodies. They not only retain the moisture retention, warmth, and weed control properties of traditional polyethylene (PE) mulch films, but also degrade through the combined action of water, light, heat, and microorganisms. They are suitable for a variety of crops, particularly root crops, and demonstrate superior yield-increasing effects compared to traditional mulch films.
Fully biodegradable mulch films with different raw material formulas have varying degradation rates and are suitable for different crops and growing environments. When choosing a mulch film, consider certification standards, crop compatibility, cost-effectiveness, and supporting technologies. Prioritize products that meet national standards and have positive user feedback. The key points to consider when choosing a mulch film are as follows:
1. Certification and Standards Product Certificate: Each roll of ground film should be accompanied by a certificate indicating the product name, category, production date, and implementation standard (e.g., "Fully Biodegradable Agricultural Ground Cover Film" (GB/T35795-2017)). The shelf life should also be kept within eight months of production. Select products with a recent production date to avoid prolonged storage and degradation.
2. Appearance and Quality. Surface inspection: No obvious defects such as bubbles, spots, wrinkles, or pinholes, with a defect density of no more than 20 per 100 square centimeters. The thickness should be uniform (e.g., 0.008-0.01 mm), with consistent color and transparency throughout the roll, and the transverse and longitudinal tensile strength meeting the standards.
3. Specification compatibility. Thickness: Choose based on crop requirements. For example, for crops with short growth periods (such as edible soybeans), a fully biodegradable mulch with a thickness of 0.006-0.008 mm is recommended. For hard soil or mechanical mulching, a fully biodegradable mulch with a thickness of 0.01-0.012 mm is recommended for enhanced strength. Width: Choose based on crop planting methods and mulching requirements to avoid wasteful use caused by excessive width or unusable use caused by excessive narrowness. Color: White mulch offers excellent warming but is easily degradable, while black mulch provides stable weed control but exhibits weaker warming.
4. Price and Subsidies. Cost Comparison: Fully biodegradable mulch is relatively expensive, but some government programs offer subsidies, so the overall cost may be comparable to that of ordinary mulch. Economic Tradeoff: Eliminating the need for initial film recovery reduces labor costs for cleanup and reduces soil pollution control costs in the long term. Government subsidies can reduce initial investment costs and provide significant long-term ecological benefits.
5. Matching the crop with the degradation cycle. Short-growing crops (such as cabbage and fresh-eating soybeans) require a 60-day degradation cycle, while long-growing crops (such as corn) require more than 90 days. Ensure that the mulch film degrades promptly after the crops are harvested.
6. Transportation and Storage: Avoid direct sunlight and rain during transportation, and avoid mixing with sharp or corrosive objects. Store in a cool, dry place. The shelf life should not exceed 8 months.
