Co-cultivation of fern with biochar and varied irrigation levels for reduced arsenic accumulation: focus on the presence of biochar and varied irrigation levels

• Main Author: Thai, Clara Xin Ying
• Other Authors: Grzegorz Lisak
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2024
• Subjects: Engineering
• Online Access: https://hdl.handle.net/10356/177114
• Institution: Nanyang Technological University

Rice is a main staple crop in Asia, where arsenic (As) contamination poses a significant threat. This issue is particularly acute in South Asia as their communities rely heavily on Asian rice for daily sustenance. Arsenic contamination in rice often originates from contaminated irrigation sources. One strategy to mitigate this is to utilise a water-tolerant rice variety, known as Hanyou-73 (HY-73), which can reduce irrigation required and hence contact of the crops with arsenic. However, one big issue is that water conditions can affect the nutrients available in the soil, and hence, the availability of nutrients that can be uptaken by the rice for optimal growth. To address this challenge, biochar is introduced to solve this issue. Biochar can not only supply nutrients but also retain water. The hypothesis is that biochar can provide essential nutrients to support rice growth in water-limited conditions. The objective of the experiment was to determine which combination of two factors, biochar and water content, would result in the lowest accumulation of arsenic, and to identify which factor had a greater impact. The results were obtained using advanced analytical instruments, such as inductively coupled plasma mass spectrometry (ICP-MS). It was shown that the HY-73 variety was indeed able to tolerate non-flooding conditions and grow optimally. The analysis revealed that water content had a significant impact on the arsenic accumulation as it presented an optimal growth environment for the rice. The higher the water content, the lower the arsenic accumulation, especially in flooded conditions. However, biochar had irregular results, having less of an impact on the arsenic accumulation in rice.