Effects of lithium resource exploitation on surface water at Jiajika mine, China.

Heavy metal and metalloid (HMM) contamination of the water environment caused by mining activities is a great challenge to the global mining industry. HMMs released by various mines could easily enter the surrounding environment and pose serious threats to human health. Although the HMM pollution of surface water in various mines has been widely researched, relevant studies on the effects of mining activities on the surface water of hard-rock-type Li mines are scarce. Herein, a total of 81 water samples were collected from Jiajika mine for the first time, the largest hard-rock-type Li mine in Asia. The physical parameters and concentrations of HMMs and major ions of the samples were analyzed to evaluate the water quality and HMM level of surface water. Results showed that (1) most of the parameters analyzed adhered to the strictest guidelines of Chinese surface waters and the drinking water guidelines of WHO, except Mn, Pb, and As of a few samples from tailings-affected areas and Li-bearing areas; (2) mineral tailings obviously increased the pH and decreased the dissolved oxygen (DO) of the surrounding surface waters; (3) the highest concentrations of As (5.58 µg/L), Zn (81.8 µg/L), Ba (5.26 µg/L), and Co (0.33 µg/L) were observed around the tailings reservoir, whereas the highest concentrations of Cr (1.5 µg/L), Mn (380 µg/L), Pb (28.4 µg/L), and V (3.16 µg/L) were observed in Li-bearing areas; and (4) according to the statistical results, the concentrations of As, Cr, Ni, and V in surface water were mainly affected by mining activities, whereas those of Cu, Zn, Ba, Co, and Pb were dominantly affected by natural processes. These results provide useful information about water quality in relation to Li mining and can help the government make reasonable decisions regarding hard-rock-type Li resource exploitation activities.

Characterization of a new male sterility-related gene Camf1 in Capsicum annum L.

For the sake of screening novel genes related to the male sterility in chili pepper for studying the molecular mechanism of plant male sterility, the gene differential expression analysis was performed by cDNA-amplified fragment length polymorphism (cDNA-AFLP) in the genic male sterile-fertile line 114AB of Capsicum annum L., and a variety of differentially expressed cDNA fragments were detected in fertile or sterility material. Camf1, a transcript-derived fragment (TDF) accumulated in fertile line flower buds was further investigated. The Camf1 has 1,854 bp in length with no introns containing a 1,707-bp open reading frame (ORF). The deduced amino acid sequence of Camf1 shares higher similarity to some members from a glyoxal oxidase-related protein family, and has a glyoxal oxidase conserved domain at the N-terminus and a domain of unknown function (DUF1929) at C-terminal end. Expression analysis showed that Camf1 expressed only in stage 3-7 flower buds of male fertile of C. annum L. 114AB, and no detection in all organs of male sterility. The peak of expression level of Camf1 appeared at stage 4 flower buds of fertile line. Furthermore, expression analysis of different organs revealed that Camf1 expressed only in anthers of male fertile material and there were no expression in sepals, petals, pistils, roots, stems, leaves and open flowers. These results suggested that Camf1 was an anther-specific gene and might be essential for the fertility of C. annum L.