Research Projects

Agricultural soils continue to encounter serious threats from excessive pesticide usage, leading to long term accumulation of toxic residues, microbial imbalance, and declining soil health globally. Mulching is one of the widely practiced methods to prevent weeds and protect soil moisture levels. However, conventional plastic mulch sheets contribute significantly to agroplastic waste and do not play a part in eliminating pesticide residues impacting soil quality. Although the biodegradable mulches available commercially possess eco-compatibility, they do not have any active functionality for soil remediation. This proposal aims to address this critical gap by developing a biodegradable, photocatalytic mulch sheet with cellulose rich natural fibers (viz., cotton, flax, or hemp) that is active under visible sunlight. The new proposed mulch will not only be a physical barrier to block the direct pesticide/soil contact but will also possess a visible light active photocatalyst embedded within its fiber matrix. Under natural sunlight, this material will generate reactive oxygen species (ROS) at its surface, utilizing the persistent moisture layer present under mulch in typical agricultural practice, where drip or subsurface irrigation maintains a humid microclimate. This production of ROS will assist in degrading surface pesticide residues and could also play a part in soil disinfection. The proposed mulching system offers a dual functionality: 1. Prevention- protection of soil from direct exposure of pesticides 2. Remediation- active degradation of surface pollutants with ambient solar energy The use of renewable, cellulose abundant plant fibers provides environmental biocompatibility and degradability, and the use of visible light photocatalysts over UV responsive ones provides added significance under natural solar irradiation conditions. A vital feature of the proposed research is the comparison of mulch performance in two practical scenarios: 1. Static soil contact- mimicking classical field mulching, where mulch & soil moisture are in contact. 2. Flow contact- mimicking mulch contact with agricultural runoff on field slopes or drains. This two-fold application strategy will expand the utility of the mulch beyond crop protection, encompassing its benefits to runoff decontamination, facilitating sustainable agriculture and environmental conservation. The application incorporates material engineering to enhance the durability and longevity of the mulching sheet under sunlight and soil moisture through the addition of surface treatments and composite structuring. To summarize, the new photocatalytic mulch provides an inexpensive, biodegradable, solar powered solution to pesticide contamination and soil conservation, the two biggest challenges in Indian agriculture. By integrating green chemistry, material innovation, and visible light photocatalysis, this project can provide a field deployable platform with scientific and social significance.