To be sure, plastic is an important part of our daily lives. Yet when that plastic gets tossed into the ocean, it can become an environmental menace.
Recent studies indicate that upwards of 0.27 million tons of plastic are adrift on our oceans. This is not good news for marine life which can consume it or get tangled in it.
Consequently, some have sought to ban the use of certain plastics outright – such as with straws and shopping bags. Unfortunately, these campaigns in the U.S. tend to have little global impact, as much of the problem is derived from Asia.
But it’s not all bad news coming from the Far East with respect to plastic. A helpful solution might now be in hand courtesy of some hard work being done in the Land of the Rising Sun — Japan.
Recently a team of researchers, led by Professor Yasuo Nihei of the Tokyo University of Science, have developed a new method of combatting plastic emissions using high resolution mapping. As reported in the University’s online website, this technique can help identify sources of where plastic is being put into waterways:
The scientists followed a three-step process to map plastic emissions. First, they measured MicP concentration across 70 rivers and 90 sites in Japan and examined the relation between MicP concentration and land characteristics. They collected the ratio of MacP/MicP concentrations to evaluate the MacP concentration from the MicP concentration. Next, to obtain outflow discharge at 1 km grids, they performed a “water balance analysis” in which they measured precipitation of water, distributed into three categories: evaporation, surface runoff, and underground infiltration. Finally, they calculate total plastic emission, which is the product of MicP and MacP concentrations and outflow discharge. Their findings revealed that MicP concentrations and basin characteristics were significantly correlated, meaning that the physical features of water bodies dictate the amount of plastic waste accumulated. Not just this, their analysis helped the scientists to estimate the annual plastic emission in Japan, which ranged from 210 to 4,776 tons/year of total plastic.
The scientists then evaluated a high-resolution map of plastic emission over 1 km grids across Japan. They identified the critical areas where plastic emissions were the highest. Their analysis showed that these emissions were high in rivers near urbanized areas, with a high population density. Among these, cities like Tokyo, Nagoya, and Osaka were found to be hotspots for plastic emissions. Thus, this method was useful in understanding exactly where strict countermeasures should be enforced.
For more information, you can read the entirety of the original article here.