Concentrations of sulphur and heavy metals in needles and rooting soils of Masson pine (Pinus massoniana L.) trees growing along an urban–rural gradient in Guangzhou, China

Abstract

Current (C) and previous year (C + 1) needles and soils (organic horizon, 0-10 cm and 10-20 cm mineral depth) of Masson pine (Pinus massoniana L.) trees were sampled at four forested sites (Huang Pu industrial district, HP; South China Botanical Garden, BG; Mao Feng Mt., MF; and Nan Kun Mt., NK) in Guangzhou along a urban-rural gradient and analyzed for sulfur (S) and heavy metals (Cu, Zn, Ni, Cd, Cr and Pb) concentrations. Needle concentrations of all the elements were significantly higher at industrial HP than at other three sites, except for Cu and Pb which were highest at the traffic site (BG). The C + 1 needles generally had higher Cu, Cd, Pb, Zn, Cr than the C needles while the opposite was for Ni and S. Total and available Cd, Pb, Zn in soils peaked at the urban sites (HP and BG) and decreased at suburban MF and rural NK. Heavy metals were generally higher in the organic soils than in the mineral soils at all sites. Zinc and Pb at all sites, and Cd, S and Cu at the urban sites (HP and BG) in soils or pine needles were above or near their respective natural background levels, implying that threats resulted from these toxic elements occurred on local particularly urban forests, but did not for Cr and Ni due to their presence below their background values. Our results demonstrated that elements concentrations in needles and soils had reflected the variability of pollutants and the environmental quality change along the urban-rural transect, and were efficient as biomonitors to assess the influence of anthropogenic activities along the urbanization course on forest health.

Assessment of Airborne Heavy Metal Pollution Using Pinus spp. and Tilia spp.

“…Having in mind the low mobility of Pb (low translocation to the aerial parts), and concerning the observed pattern of their content in leaf/needle and branch, it can be concluded that Pb arises from airborne emissions. Compared to the mean values reported in the literature (Yilmaz and Zengin, 2004;Al-Alawi and Mandiwana, 2007;Sun et al, 2009;Kord et al, 2010;Sun et al, 2010;Dmuchowski et al, 2011), concentrations of Pb in pine needles from our study area are higher. Similar or slightly lower Pb concentrations in linden leaves predominantly from traffic related sites were also reported by Piczak et al (2003), Tomašević et al (2004) and Aničić et al (2011).…”

“…Pine needles have been determined to have higher Zn concentrations than the linden leaves, at the sampling sites where both plant species were sampled. Zn concentrations in pine needles have shown to be lower in our research than the concentrations in the studies of Yilmaz and Zengin (2004), Al-Alawi and Mandiwana (2007), Yang et al (2008), and Sun et al (2009). The content of Zn in linden leaves is similar to Zn concentrations in the research of Piczak et al (2003).…”

“…It has been confirmed that both species are able to accumulate Cu, since no noticeable visual symptoms were observed (Rossini Oliva and Mingorance, 2004). The obtained copper concentrations in pine needles were higher than in the other industrial and urban areas (Yilmaz and Zengin, 2004;Al-Alawi and Mandiwana, 2007;Sun et al, 2009;Kord et al, 2010;Sun et al, 2010). The linden leaves sampled in Bor and the surroundings, have higher Cu content than the values reported by Piczak et al (2003), Tomašević et al (2004), Tomašević et al (2011) and Aničić et al (2011).…”

“…The morphology, canopy structure and epicuticular wax on the leaf surface make linden trees suitable for biomonitoring of air pollution (Braun et al, 2007). Pine needles are most frequently used for biomonitoring of airborne pollution, because of the possibility of passive and active uptake of needles tissue from the atmosphere (Mingorance et al, 2007;Sun et al, 2009;Sun et al, 2010;Kuang et al, 2011). The most frequently identified elements which cause biological/ecological harmful effects are Pb, Cs, As, Cr, Zn, Ni, and Cu.…”

Temporal variation in the arsenic and metal accumulation in the maritime pine tree grown on contaminated soils

“…2). The sampling methodology followed the orientations defined by Brooks (1983Brooks ( ), Ö zdemir (2005 and Sun et al (2009). The needles, stems and rooting soils of Pinus pinaster were collected at the five locations in late July and early August, during the dry season of the year.…”