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Plant leaves can accumulate particulate matter (PM) from the air, thus mitigating air pollution. Nine plant species from the central part of Shanxi Province, China, were investigated to characterize differences in their PM retention capacity and the grain sizes of the collected PM. Styphnolobium japonicum, Syringa oblata, and Cerasus serrulata demonstrated strong retention capacity for PM particles of diverse size fractions. Philadelphus incanus, Viburnum opulus, and Yulania biondii had relatively weak retention capacity for overall and fine PM. Generally, species with smaller leaves and roughness surfaces, waxy leaves, or leaves with hair had strong PM retention capacity. Leaves with suitable groove widths better retained fine PM. Foliar dust observed on leaves presented multimodal distribution curves, including bimodal, trimodal, and four-peak distributions, which differed from the trimodal distribution of natural dustfall. The different PM retention capacities of the nine investigated species and the differing grain sizes between foliar dust and atmospheric dustfall indicated that plant leaves could selectively retain PM. The results of this study provide a scientific basis for the use of the plant to mitigate particulate air pollution. [ABSTRACT FROM AUTHOR]

Obtaining surface albedo of high accuracy and analyzing spatial and temporal characteristics are essential for detecting change mechanism and influencing factors of surface albedo in deserts. Surface albedo from the Operational Land Imager (OLI) was assimilated into black-sky short-wave albedo (BSA) with an ensemble Kalman filter (EnKF) algorithm, to retrieve the surface albedo of high accuracy in Badain Jaran Desert. The results show that the average relative error decreases from 14.813% to 8.530% when surface albedo based on OLI is assimilated into BSA with the EnKF, and assimilated value can accurately describe the spatial and temporal distribution of surface albedo. The surface albedo has an obvious seasonal difference and presents a U-shape curve in a year, with the highest albedo in winter and lowest in summer. Owing to snow cover in some high-altitude areas, surface albedo is the highest and the spatial difference reaches maximum (variation coefficient=0.14) in winter. The Structure Similarity in surface albedo increases from the hinterland of desert (0.40–0.70) to the outer areas (0.70–0.90), as dune number decreases and distance between dunes increases. Compared with mobile and semi-mobile dunes, the minimum surface albedo of semi-fixed and fixed dunes postpones one month due to lag effect of the vegetation response to precipitation. [ABSTRACT FROM AUTHOR]

To understand the salinity, redox characteristics, and climatology of Dali Lake during the late Holocene, we analysed trace element records from a high-resolution sediment core (DL-1), including Al, Mn, Zn, Mo, Pb, Fe, Sr, and Ba. The core was dated to 2100 cal BP based on accelerator mass spectrometry (AMS) 14C dating combined with the constant rate of supply (CRS) model. We identified five palaeoclimatic stages based on the down-core trace elemental characteristics. From ca. 2100 to 1650 cal BP (Stage Ⅰ), Mn-MAR (mass accumulation rates) and Fe-MAR showed no correlations with Mo-MAR, suggesting that anaerobic conditions limited the adsorption of Mo onto Mn–Fe oxides. From ca. 1650 to 1050 cal BP (Stage Ⅱ), we identified a weakened aerobic environment, coinciding with the Dark Ages Cold Period due to a decrease in the organic matter (OM), nutrients, Fe-MAR, and Zn-MAR, which inhibited Mo deposition. Salinity (Sr/Ba) did not influence the trace elemental fluxes, OM, or nutrients throughout Stages I and II. We identified aerobic conditions during Stage Ⅲ (between ca. 1050 and 650 cal BP), coinciding with the Medieval Warm Period, with observed lower salinity that facilitated Al-MAR, Mn-MAR, and Pb-MAR deposition. During the Little Ice Age (between ca. 650 and 30 cal BP; Stage Ⅳ), Mn-MAR, Zn-MAR, and Fe-MAR showed no correlation with Mo-MAR, implying anaerobic conditions. We also identified high salinity and OM concentrations that facilitated trace element deposition. Over the past 95 years (Stage V), high salinity levels have produced the deposition of Al-MAR, Mn-MAR, Zn-MAR, and Fe-MAR. However, the redox conditions in the lake sediment are difficult to interpret due to anthropogenic influences on trace elemental fluxes. We identified a salinity periodicity (Sr/Ba) of 100–150 years and a redox periodicity (Mo-MAR) of 100–260 years using the wavelet power spectrum. Our results indicate a gradual weakening of the East Asian summer monsoon, which may be controlled by insolation in the Dali Lake basin. • Five climate stages were identified over the past 2100 years. • Dali Lake salinity alternated between fresh, brackish, and oceanic phases. • Salinity variability showed a periodicity of 100–150 years. • Redox conditions showed a periodicity of 100–260 years. • Trace element-climate links inferred weakening of the East Asian summer monsoon. [ABSTRACT FROM AUTHOR]

Roadside soils are regarded as a reservoir for heavy metal pollution, which potentially leads to ecosystem deterioration as well as serious hazard to human health. A comprehensive investigation was conducted for the levels, relationship with soil properties, and potential sources of heavy metals (Hg, Cu, Zn, Pb, Cd, and Cr) in roadside soils in six cities (Changzhi, Jincheng, Yuncheng, Linfen, Xinzhou, Datong) of Shanxi Province; and the corresponding ecological risk and human health risk associated with the concentrations of heavy metals were addressed. Heavy metal concentrations of 112 roadside soil samples in the surveyed cities were, in decreasing order, Zn, Cu, Cr, Pb, Cd, and Hg, which were higher than corresponding background values. The highest concentrations were in Changzhi. The results of Pearson correlation analysis demonstrated that positive correlations in varying degrees existed between soil properties such as electrical conductivity, total nitrogen, total phosphorus, and total organic carbon with specific heavy metals and that negative correlations were observed for clay and electrical conductivity. Anthropogenic sources related to traffic emissions and industrialization were the main sources of heavy metals in roadside soils according to principal component analysis. The ecological risk assessments were achieved by pollution index and potential risk index, indicating that contamination with Hg was the most serious, which posed the highest risk to the ecosystems in the surveyed cities; and the ecological risk in Changzhi ranked at the top compared with other cities. For the human health risk assessment, the results demonstrated that the noncarcinogenic and carcinogenic risks were in the acceptable range in the surveyed cities. However, there was a higher health risk from heavy metal exposure for children than adults, and the main exposure pathway was soil ingestion. In addition, Changzhi was the city with the highest noncarcinogenic and carcinogenic risks, and the main human health risks were posed by Cr contamination in roadside soil, which was different from the results of ecological risks. Both results of ecological and health risk assessment demonstrated that the higher risk exhibited in southern and southeastern cities than northern cities in Shanxi Province. Environ Toxicol Chem 2023;42:1485-1500. © 2023 SETAC., (© 2023 SETAC.)