The Plastic Cycle - An Unknown Branch of the Carbon Cycle

As early as the 1970s, plastic pollution has been reported in the environment (Carpenter and Smith, 1972). Then in the late 1990s, a sea captain discovered large amounts of plastic accumulating in the North Pacific Gyre (Moore et al., 2001), which is referred to as the North Pacific Garbage Patch. Now in 2020, plastic pollution is ubiquitous in the environment-from remote mountain lakes (Free et al., 2014) to the deep abyss of the ocean (Jamieson et al., 2019) to the very air we breathe (Liu et al., 2019; Brahney et al., 2020). It is clear that plastic pollution has become a major environmental issue of our time. Due to the low degradation rates of plastic, almost every piece of plastic that is produced is still somewhere on this planet. But when asked where is all the plastic? or how much plastic is in the ocean or in freshwater ecosystems?, the most common answer is we don't know. To this day, the ultimate fate of plastic pollution and its transport mechanisms in terrestrial, freshwater, and marine environments are poorly understood, both on a regional and global scale. How do we begin to tackle such an immense gap in our understanding of plastic pollution? To guide our efforts to understand the fate and transport of plastic in the environment, I suggest considering the plastic cycle-borrowing from frameworks used for carbon, nitrogen, or phosphorus (Dolman, 2019). We can use frameworks built within biogeochemical cycles to help fill in all of the unknowns within the plastic cycle. We might even consider the plastic cycle as an unknown branch of the carbon cycle, such that research on plastics ultimately contributes to our understanding of how carbon cycles in the environment.

Automated summary

Plastic pollution has become a major environmental issue, with its fate and transport mechanisms remaining poorly understood in terrestrial, freshwater, and marine environments. To address this gap in understanding, it is suggested to consider using frameworks from other cycles to comprehend the plastic cycle.