Title

The effect of hyperaccumulator biochar application on soil properties and plant growth of Vigna radiata

School Name

Spring Valley High School

Grade Level

11th Grade

Presentation Topic

Environmental Science

Presentation Type

Non-Mentored

Abstract

Unlike fertilizers that lead to nitrate leaching, biochars have emerged as a natural way to increase plant nutrient uptake and crop yields and to improve soil acidity and quality. However, often large biochar amendments are required to produce significant effects on soil. This study aimed to determine the effectiveness of biochar made with hyperaccumulator plants, which are characterized by high cellulose levels and porosity. It was hypothesized that hyperaccumulator biochar-amended soil would lead to an increase in soil pH over time, plants with higher root to shoot ratios and total dry mass yields, and higher amounts of nitrogen, phosphorus, and potassium than wood biochar amended soil and soil with no amendment. Biochar was made from sunflower, kale, and pine wood bark at 330℃, and mung beans were grown in a 2% biochar soil mixture for 75 days. There was no significant difference between the effects of the different types of biochar on soil pH, nitrogen, potassium, or plant root to shoot ratios (p>0.05). However, biochar-amended soil showed increased phosphorus retention (K(3)=12.786, p=0.005). The relationship between soil pH and time was modeled by a quadratic trend (F(3, 180)=3.21, p=0.024<ɑ=0.05), as pH decreased for 60 days and then increased, while the control decreased constantly (p=0.057>ɑ=0.05). Plants in the bark and control groups had significantly higher total dry masses than those in the kale group, while dry masses of plants in the sunflower group were not significantly different from any others (F(3, 27)=5.02, p=0.007<ɑ=0.05). It can be concluded that, while not more advantageous than bark biochar, hyperaccumulator biochar is an equally effective way to increase soil cation-exchange capacity, while repurposing contaminated hyperaccumulator plants.

Location

Lassiter 222

Start Date

4-14-2018 11:15 AM

Presentation Format

Oral and Written

COinS
 
Apr 14th, 11:15 AM

The effect of hyperaccumulator biochar application on soil properties and plant growth of Vigna radiata

Lassiter 222

Unlike fertilizers that lead to nitrate leaching, biochars have emerged as a natural way to increase plant nutrient uptake and crop yields and to improve soil acidity and quality. However, often large biochar amendments are required to produce significant effects on soil. This study aimed to determine the effectiveness of biochar made with hyperaccumulator plants, which are characterized by high cellulose levels and porosity. It was hypothesized that hyperaccumulator biochar-amended soil would lead to an increase in soil pH over time, plants with higher root to shoot ratios and total dry mass yields, and higher amounts of nitrogen, phosphorus, and potassium than wood biochar amended soil and soil with no amendment. Biochar was made from sunflower, kale, and pine wood bark at 330℃, and mung beans were grown in a 2% biochar soil mixture for 75 days. There was no significant difference between the effects of the different types of biochar on soil pH, nitrogen, potassium, or plant root to shoot ratios (p>0.05). However, biochar-amended soil showed increased phosphorus retention (K(3)=12.786, p=0.005). The relationship between soil pH and time was modeled by a quadratic trend (F(3, 180)=3.21, p=0.024<ɑ=0.05), as pH decreased for 60 days and then increased, while the control decreased constantly (p=0.057>ɑ=0.05). Plants in the bark and control groups had significantly higher total dry masses than those in the kale group, while dry masses of plants in the sunflower group were not significantly different from any others (F(3, 27)=5.02, p=0.007<ɑ=0.05). It can be concluded that, while not more advantageous than bark biochar, hyperaccumulator biochar is an equally effective way to increase soil cation-exchange capacity, while repurposing contaminated hyperaccumulator plants.