The Effect of Microplastic Size and Type on the Growth of Brassica rapa

School Name

Spring Valley High School

Grade Level

10th Grade

Presentation Topic

Environmental Science

Presentation Type

Non-Mentored

Abstract

Concerns have been raised about the effects of the growing amount of plastic pollution in soil, particularly microplastics (plastic particles less than 5 mm in diameter), on the physicochemical characteristics of the soil and, consequently, on the nutrient cycle and plant health. Biodegradable plastics have been introduced as an alternative, but issues persist as they break down into smaller pieces easily consumed by animals and microbes. This study investigates the effects of microplastic size and biodegradability on Brassica rapa growth to imitate soil health and stimulate more research on plastic biodegradability and size effects in terrestrial ecosystems. This study aimed to compare the non-biodegradable polystyrene and biodegradable polylactic acid, hypothesizing that smaller non-biodegradable microplastics hinder the growth of Brassica rapa compared to their counterparts. 150 Brassica rapa plants were used to evaluate the effects of 1 mm and 5 mm microplastic lengths and their biodegradability throughout a 17-day period by being grown with the microplastics directly. At the end of the 17 days, the Brassica rapa were measured by stem height, and data was used to run an ANOVA. The results found there was no significant difference in the size of microplastics. This finding eliminates the need for a two-way ANOVA comparing microplastic size and type. An unpaired one-way ANOVA, focusing on microplastic type, suggests no statistically significant differences between the polystyrene and polylactic acid groups at 1 mm (p = .223) and 5 mm (p = 0.063). Accordingly, it was concluded the evidence is insufficient to determine a clear difference.

Location

RITA 154

Start Date

3-23-2024 10:15 AM

Presentation Format

Oral and Written

Group Project

No

COinS
 
Mar 23rd, 10:15 AM

The Effect of Microplastic Size and Type on the Growth of Brassica rapa

RITA 154

Concerns have been raised about the effects of the growing amount of plastic pollution in soil, particularly microplastics (plastic particles less than 5 mm in diameter), on the physicochemical characteristics of the soil and, consequently, on the nutrient cycle and plant health. Biodegradable plastics have been introduced as an alternative, but issues persist as they break down into smaller pieces easily consumed by animals and microbes. This study investigates the effects of microplastic size and biodegradability on Brassica rapa growth to imitate soil health and stimulate more research on plastic biodegradability and size effects in terrestrial ecosystems. This study aimed to compare the non-biodegradable polystyrene and biodegradable polylactic acid, hypothesizing that smaller non-biodegradable microplastics hinder the growth of Brassica rapa compared to their counterparts. 150 Brassica rapa plants were used to evaluate the effects of 1 mm and 5 mm microplastic lengths and their biodegradability throughout a 17-day period by being grown with the microplastics directly. At the end of the 17 days, the Brassica rapa were measured by stem height, and data was used to run an ANOVA. The results found there was no significant difference in the size of microplastics. This finding eliminates the need for a two-way ANOVA comparing microplastic size and type. An unpaired one-way ANOVA, focusing on microplastic type, suggests no statistically significant differences between the polystyrene and polylactic acid groups at 1 mm (p = .223) and 5 mm (p = 0.063). Accordingly, it was concluded the evidence is insufficient to determine a clear difference.