Industrial Solid Waste Management Study Highlights Potential for Plant Restoration.
Industrial solid waste (ISW) management is a pressing environmental issue, particularly in regions where waste disposal affects soil quality and plant health. A recent study from Government College University investigated the growth of two plant species, Conocarpus erectus (an alien species) and Dodonaea viscosa (an indigenous species), in various mixes of industrial solid waste and garden soil. The research aims to evaluate how these plants could help restore barren lands impacted by industrial waste.
The researchers created soil mixtures with different proportions of industrial waste and garden soil: 0% (T0), 5% (T1), 10% (T2), 15% (T3), and 20% (T4). They monitored the growth, physiological changes, anatomical changes, and ion uptake (Na+, K+, Ca2+, and Mg2+) in both the shoots and roots of the plants over four months.
Results showed that Conocarpus erectus grew better and absorbed more ions than Dodonaea viscosa. By the fourth month, the height of C. erectus in T1 increased by 24.5%, while D. viscosa’s height increased by 46%. However, D. viscosa experienced a significant decline in the fresh and dry weights of its roots and shoots in T1, T2, and T3, ultimately leading to its death in T3 and T4. In contrast, C. erectus maintained stable weights across all treatments, indicating greater tolerance to industrial solid waste.
These findings support previous research on the effects of industrial waste and salinity on plant growth and heavy metal absorption. For example, a study on cucumber plants revealed that while industrial solid waste raised heavy metal levels in soil, certain wastes, like sugar factory waste (SFW), improved plant growth under saline conditions. In this study, the optimal waste-to-soil ratio for growing D. viscosa was 10:90, while C. erectus thrived better in a 20:80 ratio, emphasizing the potential for these plants in phytoremediation efforts.
Additionally, the study aligns with research on how salinity and nutrients affect plant health. For instance, Eucalyptus grandis trees showed improved growth and photosynthesis when provided with adequate potassium (K) and sodium (Na) in potassium-deficient soils. This mirrors the current findings, as C. erectus demonstrated more efficient ion uptake, suggesting its capacity to adapt to nutrient imbalances caused by industrial solid waste.
Research on barley plants also indicated that adding calcium (Ca2+) could help reduce the negative effects of salinity on root growth and ion absorption. This supports the current study’s conclusion that suitable soil mixtures can lessen the harmful impacts of industrial solid waste on plant growth.
In summary, the study from Government College University sheds light on the potential of Conocarpus erectus and Dodonaea viscosa for rehabilitating lands contaminated by industrial waste. The findings highlight the importance of selecting the right plant species and soil combinations to boost growth and ion uptake, contributing to sustainable management of industrial waste and ecosystem restoration.