A Review of Carbon Nanotubes’ Effects on Plant Growth and Their Environmental Impact
Against the backdrop of global warming and rapid population growth, issues such as limited arable land and soil degradation and water pollution caused by the overuse of traditional chemical fertilizers are becoming increasingly severe. Developing new agricultural technologies to ensure food security has become a global consensus. Carbon nanotubes (CNTs), with their unique physicochemical properties—including high specific surface area, excellent conductivity, and environmental friendliness—offer innovative solutions to these challenges and serve as key materials for promoting sustainable agricultural development. Research indicates that CNTs can optimize plant growth in multiple dimensions, including promoting water transport and nutrient absorption, as well as regulating endogenous plant hormones and antioxidant systems. These beneficial effects can also significantly enhance crop resilience under adverse conditions such as drought and salinity. When faced with heavy metal or pesticide residue contamination, CNTs can alleviate stress by reducing the bioavailability of toxins. Furthermore, as novel carriers for fertilizers and pesticides, CNTs not only enable the slow release of active substances to enhance efficacy but also facilitate the construction of microsensors, supporting precision monitoring and virus control in smart agriculture. However, concerns remain regarding the ecological safety of CNTs. Their environmental degradation mechanisms are unclear, and they are prone to bioaccumulation; moreover, their effects on plants and soil microorganisms vary depending on type, concentration, and exposure duration. Compounding this complexity, CNTs may exhibit synergistic toxicity with environmental pollutants, and their long-term ecological risks urgently require assessment. This research focuses on the microscopic mechanisms by which CNTs promote the growth of major crops, their practical application efficacy, and their potential disruption of soil ecosystems. It aims to systematically evaluate the agricultural application potential of CNTs, providing a theoretical basis for maximizing their agronomic benefits while mitigating ecological risks, ultimately contributing to global food security and the green transformation of agriculture.