Fig 1.
Location of the e-waste exposed, e-waste surrounding and natural reference sites where bird population densities were measured in Guangdong, China.
Study sites are coded by different treatments as black circles (exposed, i.e. BHT-Baihetang, CC-Changchong, BC-Banchong), white and black circles (surrounding, i.e. MT-Matou, QL-Qinglian, AF-Anfeng), and white circles (natural, i.e. ZX-Zhouxi, XL-Xinliang, GQ-Gaoqiao). Photo tip: the scene of recycling workshop, polluted river and dumping site in e-waste area.
Table 1.
Upper part: the major habitat characteristics where birds were censused for this study.
Fig 2.
Sampled-based rarefaction curves (a); box and whisker plots comparing mean point species richness, abundance, and diversity among sites from e-waste exposed (n = 30), surrounding (n = 30) and reference sites (n = 30), occurring in breeding (b) and winter (c) season.
Curves were generated by Monte-Carlo simulations with 95% confidence intervals (on the total number of species vs. individuals observed). Site estimates are based on standardized point counts where bird numbers were counted for 10 min at each plot. Each point was counted four times totally. Different letters at each box indicate significant differences at a = 0.05. P values are derived from F tests that use the type III sums-of-squares obtained from linear mixed models.
Fig 3.
(a) Cluster analysis of bird communities of the 9 transects-villages using Sorensen similarity index as input. (b) Correspondence analysis (CA) ordination of count points with superimposed groups from e-waste exposed (n = 30), surrounding (n = 30) and reference sites (n = 30).
See Fig. 1 for map of sites, and S1 Table for a summary of bird abundances.
Fig 4.
Changes in the relative abundance of birds grouped by (a) habitat preference, (b) dietary guilds, and (c) migratory status.
Habitat preference codes: “artificial marshland or wetland (AW)”; “aquatic ponds and paddy (AP)”; “woodland specialist (WS)”; “edge-tolerant woodland species (EWS)”; “non-forest dependent species (e.g., plantation and orchard; NFS)”; “generalist (G)”; “aerial species (A)”; “grassland and shrub users (GSU)” and “open-habitat species (OS)”. Dietary guild codes: “carnivore (CA)”, “arboreal foliage glean insectivore (AI)”, “arboreal foliage glean insectivore-frugivore (AIF)”, “sallying insectivore (SI)”, “terrestrial insectivore (TI)”, “miscellaneous insectivore (MI)”, “terrestrial insectivore-frugivore (TIF)”, “arboreal frugivore (AF)”, “terrestrial granivores (TG)”, “miscellaneous insectivore-piscivore (MIP)”, and “aquatic invertebrate (AQI)”. Different letters at each box indicate significant differences at a = 0.05. P values are derived from F tests that use the type III sums-of-squares obtained from linear mixed models.
Table 2.
Relative abundance for nine resident species that were detected significantly decreased from natural reference to e-waste polluted zone.