Using bioenergy crop cassava (Manihot esculenta) for reclamation of heavily metal-contaminated land

• Published in: International journal of phytoremediation Vol. 22; no. 12; pp. 1313 - 1320
• Main Authors: Shen, Shili, Chen, Jinquan, Chang, Junjun, Xia, Beicheng
• Format: Journal Article
• Language: English
• Published: United States Taylor & Francis 14.10.2020; Taylor & Francis Ltd
• Subjects: Acidic soils; Acidity; Agricultural economics; Agricultural land; Agricultural pollution; Agronomy; Alternative energy sources; Bioavailability; bioenergy plant; Biofuels; Cassava; Contaminated land; Crops; Cultivation; Dabaoshan Mine; Derelict land; Economic impact; Economics; Energy crops; Ethanol; Food chains; Food consumption; Food contamination; Food webs; Health risks; Heavy metals; Land pollution; Land reclamation; Manihot esculenta; Metal concentrations; Phytoremediation; reclamation; Renewable energy; Sediment pollution; Soil contamination; Soil fertility; Soil pollution; Soils; Sustainability; bioenergy plant; reclamation; heavy metals; Cassava; Dabaoshan Mine
• ISSN: 1522-6514; 1549-7879
• DOI: 10.1080/15226514.2020.1768512

Heavy metal contamination of agricultural lands may give rise to health risks by cultivation and consumption of food crops from such lands, as well as result in economic loss. Phytoremediation is an eco-friendly and cost-effective approach to restore contaminated soil. However, the restoration process is slow and its sustainability is difficult to maintain. Bioenergy crops may provide alternative economic benefits to agriculture sector and reduce the risks associated with transfering heavy metals into food webs. In this study, a field experiment was carried out to determine the level of reclamation that would be attained in severely heavy metal-contaminated land by planting cassava (Manihot esculenta), a bioenergy crop. The results showed that cassava could grow well on the derelict land, with a fresh tuber yield of 23.13-26.22 t ha −1 in one growing season, which could potentially produce 3680-4160 L ha −1 bioethanol. The economic income of the cassava was estimated to be 11.6-13.1 × 10 3 CNY ha −1 . Among the cassava tissues, metal concentrations were lowest in the tuber. The soil fertility and acidity were ameliorated after cassava plantation, and the mobile and bioavailable metal fractions in the soils were decreased. The cultivation of cassava as a renewable energy crop appears applicable for sustainable utilization and reclamation of heavy metal-contaminated land.