Global plastic pollution has been a serious problem since many years and micro (nano) plastics (MNPs) have gained attention from researchers around the world. This is because MNPs able to exhibit toxicology and interact with potentially toxic elements (PTEs) in the environment, causing soil toxicity. The influences of MNPs on the soil systems and plant crops have been overlooked despite that MNPs can accumulate in the plant root system and generate detrimental impacts to the terrestrial environments. The consumption of these MNPs-contaminated plants or fruits by humans and animals will eventually lead to health deterioration. The identification and measurement of MNPs in various soil samples is challenging, making the understanding of the fate, environmental and ecological of MNPs in terrestrial ecosystem is limited. Prior to sample assessment, it is necessary to isolate the plastic particles from the environment samples, concentrate the plastic particles for analysis purpose to meet detection limit for analytical instrument. The isolation and pre-concentrated steps are challenging and may cause sample loss. Herein, this article reviews MNPs, including their fate in the environment and toxic effects exhibited towards soil microorganisms, plants and humans along with the interaction of MNPs with PTEs. In addition, various analysis methods of MNPs and management of MNPs as well as the crucial challenges and future research studies in combating MNPs in soil system are also discussed.
This paper provides a mini review of liquid biofertilizers, which have been proven to perform better than the other forms in lasting for longer periods of time, improving crop quality, and requiring less amounts for application. The production of liquid biofertilizers, types of liquid inoculants, and their effect on plant growth are covered in this review. Liquid biofertilizers can be made from wastes and by-products of several industries, making zero or near-zero discharge possible and thus gearing towards circular economy. Despite their usefulness in enhancing crop quality and eco-friendliness, in order to compete with chemical fertilizers, there are a number of challenges to overcome, such as extending the shelf life, making them more susceptible to seasonal climate conditions and soil types, and development of suitable machineries for production and application. More field trials, cost-benefit analysis and long-term studies should also be evaluated for commercialization purposes.