Phytoremediation using woody plants can effectively reduce heavy metal (HM) concentrations in soils. However, the remediation capacity of woody plants depends greatly on plant species and soil environmental conditions. In order to evaluate the HM remediation potential of woody plants from different tailing areas, the HM accumulation characteristics of roots, shoots, and leaves of 12 dominant native woody plants growing in iron and lead-zinc tailing areas were analyzed. The results showed that the concentrations of Cd, As, Ni, Mn, and Cr in most plants in the two tailing areas exceeded the level of normal plants. The distribution of different elements in plants was generally as follows: root > leaf > shoot for Pb and As; root > shoot > leaf for Cr; and leaf > shoot > root for Zn, Ni, and Mn. The distribution of Cu and Cd in plants varied with the type of HM pollution in the two tailing areas. There were significant (p < 0.05) negative correlations between available phosphorus in the soil and Pb, Cd, and Zn in the plant roots when the soil was heavily polluted with Pb, Cd, and As; similarly, there were significant (p < 0.01) negative correlations between readily available potassium in the soil and Pb, Zn, and Ni in plant roots. Based on the higher than average concentration of HMs in plants, and higher bioconcentration factors and translocation factors, some plants were considered woody plant species with phytoremediation. Slash pine (Pinus elliottii) and indian azalea (Rhododendron simsii) had strong enrichment and translocation abilities for Cd, oriental white oak (Quercus glauca) and beautiful sweetgum (Liquidambar formosana) for Mn and paulownia (Paulownia fortunei) for Zn. The plants listed above can be used as potential species for phytoremediation in iron and lead-zinc tailing areas.
Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.) is an important plantation tree species in China, and seed germination is a key step in forest tree cultivation. To reveal the gene expression network and molecular mechanisms in the germination of Chinese fir seeds, physiological indexes were measured and transcriptome and metabolome analyses were performed on Chinese fir seeds in four stages of germination (imbibition stage, preliminary stage, emergence stage, and germination stage). All six physiological indicators had significant differences at different developmental stages. In transcriptome and metabolome analysis, we identified a large number of differentially expressed genes (DEGs) and differentially accumulated metabolites (DAMs). Gene Ontology (GO) analysis showed a large number of DEGs associated with cell growth, and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that DEGs were significantly enriched in the flavonoid biosynthesis, phenylpropanoid biosynthesis, and plant hormone signal transduction pathways. The KEGG enrichment results of DAMs were similar to those of DEGs. The joint analysis of DEGs and DAMs indicated that flavonoid biosynthesis and phenylpropanoid biosynthesis were the key pathways of Chinese fir seed germination. Our study revealed a number of key genes and key metabolites, laying the foundation for further studies on the gene regulatory network of Chinese fir seed germination.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.