In response to the current serious problem of soil cadmium (Cd) contamination in agricultural land, phytoremediation technology is a green and environmentally friendly application prospect; however, its remediation efficiency is currently limited. An enhanced phytoremediation technique was constructed using the biodegradable chelator aspartate diethoxysuccinic acid (AES) combined with the plant growth regulator gibberellic acid (GA3) to enhance the formation of maize. This technique has been proven to have a superior remediation effect. However, the safety of the restoration technique is of particular importance. The remediation process not only removes the contaminants, but also ensures that the original structure and stability of the soil is not damaged. In this regard, the constructed enhanced phytoremediation technique was further investigated in this study using soil columns. In combination with microscopic tests, such as X-ray diffraction and scanning electron microscopy, this study investigated the effects of the remediation process on the distribution characteristics of Cd in soil aggregates, and the structure and stability of soil aggregates. This was conducted by analyzing, as follows: plant growth conditions; the morphology, structure and mineral composition of soil aggregates in different soil layers; and the changes in these characteristics. The results demonstrated that the enhanced phytoremediation technique constructed in this study has a negligible impact on the morphology and mineral composition of soil aggregates, while exerting a limited influence on soil structure stability. This indicates that the technique can facilitate the safe utilization of remediated contaminated soil.

Rapid economic development has led to an alarming increase in soil pollution by potentially toxic elements (PTEs), significantly reducing soil productivity and posing long-term threats to sustainable agriculture and human well-being. Over the past two decades, it has been observed that soil PTEs pollution has severely impacted biodiversity, with damage rates of 94.7 % in plants, 77.4 % in humans, and 68.4 % in animals. In response, various remediation technologies have been developed, considering factors such as practical applicability, treatment duration, and ecological safety. Microbial remediation has shown a PTEs removal efficiency ranging from 32.0 % to 95.2 %, while multi-technology combined remediation approaches have demonstrated broader efficacy, with removal rates ranging from 18.7 % to 381 %. However, the selection of a suitable remediation technology must also consider the cost to ensure efficient contaminant removal. This review provides a comprehensive overview of the local and international status, sources, and hazards associated with PTEs, as well as the environmental factors influencing their migration. It also examines the detoxification mechanisms of plants and microbial remediation and evaluates the strengths and weaknesses of physical, chemical, biological, and combined remediation methods. Furthermore, it underscores the requirements and opportunities for developing effective PTEs removal techniques. The insights presented here are crucial for agronomists in developing soil remediation strategies and for interdisciplinary research into integrated emission sources and pathogenesis, thereby enhancing efforts to safeguard the Earth's ecological environment.