The area around Qinghai Lake is one of the most serious desertification areas on the Qinghai-Tibet Plateau. In this paper, combined with field investigation and indoor analysis, the classification and grading system of desertification around Qinghai Lake was established. On this basis, through remote sensing data processing and parameter inversion, the desertification monitoring index model was established. Based on the analysis of Landsat-5/TM remote sensing data from 1990 to 2020, the dynamic change characteristics of desertification land around Qinghai Lake in recent 30 years were obtained. The results show that the desertification area around Qinghai Lake was 1,359.62 km2, of which the light desertification land was the main one. The desertification spread in a belt around Qinghai Lake, concentrated in Ketu sandy area in the east, Ganzi River sandy area in the northeast, Bird Island sandy area in the northwest, and Langmashe sandy area in the southeast. From 1990 to 2000, the annual expansion rate of desertification around Qinghai Lake was 2.68%, the desertification spread rapidly, and light desertification land was the main part of desertification expansion. From 2000 to 2010, the annual expansion rate of desertification was only 0.83%, but severe desertification land and moderate desertification land developed more rapidly than in the previous period. From 2010 to 2020, the annual expansion rate of desertification was 2.66%, and the desertification was spreading rapidly, mainly with moderate desertification land and light desertification land. In the process of desertification land transfer around Qinghai Lake, the transfer of desertification land and non-desertification land was the main, accompanied by the mutual transformation of different levels of desertification land. The process of desertification around Qinghai Lake was essentially the result of natural and human factors. The special geographical location, climate changes, rodent damage, and human factors around Qinghai Lake were the main causes of desertification.

High concentration of surface ozone (O3) will cause health risks to people. In order to analyze the spatiotemporal characteristics of O3 and assess O3 exposure and health risks for different age groups in China, we applied multiple methods including standard deviation ellipse, spatial autocorrelation, and exposure–response functions. Results show that O3 concentrations increased in 64.5% of areas in China from 2013 to 2018. The central plain urban agglomeration (CPU), Beijing-Tianjin-Hebei (BTH), and Yangtze River Delta (YRD) witnessed the greatest incremental rates of O3 by 16.7%, 14.3%, and 13.1%. Spatially, the trend of O3 shows a significant positive autocorrelation, and high trend values primarily in central and east China. The proportion of the total population exposed to high O3 (above 160 μg/m3) increased annually. Compared to 2013, the proportion of the young, adult, and old populations exposed to high O3 increased to different extents in 2018 by 26.8%, 29.6%, and 27.2%, respectively. The extent of population exposure risk areas in China expanded in size, particularly in north and east China. The total premature respiratory mortalities attributable to long-term O3 exposure in six urban agglomerations were about 177,000 in 2018 which has increased by 16.4% compared to that in 2013. Among different age groups, old people are more vulnerable to O3 pollution, so we need to strengthen their relevant health protection of them.

The characterization of non-point source pollution at the watershed scale difficult owing to its distributed nature combined with the lack of suitable measurements for validation. This study proposes the classification of land within a Mediterranean watershed according to its potential source of non-point pollution, considering interannual precipitation variability and dam regulation effects. For this purpose, the potential non-point pollution index (PNPI) developed by the Italian Environmental Protection Agency was modified to include annual local precipitation behavior, named local annual PNPI (APNPI). PNPI and APNPI were computed for the Guadalquivir River (Spain), which has a drainage surface of 57,500 km2 and is highly regulated by >60 reservoirs. The results reflect the vulnerability along the Guadalquivir River in terms of the spatially variable non-point pollutant nature of its contributing watersheds. The annual average nitrate concentration values on the southern side exceeded the average value on the northern side by almost five times and showed a statistically significant power fit with the PNPI, with an R2 of 0.65. Long-term available nitrate data (1981/82–2006/07) on a monthly scale at the outlets of some watersheds allowed us to rank priority pollutant source areas within the watershed. The power fits between the annual average nitrate loads and the APNPI (R2 = 0.51–0.99) were statistically significant, which validated the utility of adding the variability of precipitation at an annual scale as a dynamic factor in the index. The APNPI can constitute a simple dynamic classification index for assessing the relative risk of non-point source pollution across a large area, especially in data-scarce situations.

Recently, environment pollution around the globe has increased because of anthropogenic activities. As part of the biota, plants can assimilate the compounds present in air, water and soil and respond to changes in surround conditions, for that, they can be used as bioindicators of global pollution. However, urban plants' ability to monitor organic pollutants in air, soil, and water have not been profoundly studied yet. Anthropogenic contamination produced by five different types of pollutants [polycyclic aromatic hydrocarbons (PAHs), pharmaceuticals and personal care products (PPCPs), perfluoroalkyl substances (PFASs), pesticides and organophosphorus flame retardants (OPFRs)] has been studied in Riyadh and Abha areas (Saudi Arabia). In addition to the points in both cities, a control point located in the Asir National Park (close to Abha), which is little affected by human activity, was used. The 5 groups of contaminants were found with different but high detection frequencies from 85 % to 100 % in wild and ruderal plants. PAHs were detected in all the analyzed samples at the highest average sum of concentrations (ΣPAHs) 1486 ng·g−1 dry weight (d.w.). Statistically significant differences were obtained between Riyadh, Abha and the point located in the national park (p < 0.05). ΣPAHS in Riyadh >> ΣPAHs in Abha > ΣPAHs in the National Park. Values of the average sum of concentrations for the other groups of contaminants ΣPPCPs, ΣPFASs, Σpesticides and ΣOPFRs were 420.5, 171, 48 and 47 ng g−1 d.w., respectively. High values of PPCPs are due to the presence of salicylic acid. Differences in the average sum of each type of contaminant concentrations between cities were not statistically significant. The results of this assessment of wild and ruderal plants as bioindicators for 5 types of organic contaminants suggest that they can be used to monitor anthropogenic contaminants in the terrestrial environment.

Sulfide mining wastes may lead to severe environmental and human health risks. This study aims to use geochemical and ecotoxicological indicators for the assessment of the ecological risks of potentially toxic elements (PTEs) in the San Quintín mining group to categorize wastes prior to mining restoration. Ecotoxicity was evaluated using crustacean (Dahpnia magna, Thamnocephalus platyurus) and algae (Raphidocelis subcapitata) bioassays. The geochemical and mineralogical results suggested that the mining residues underwent intense weathering processes, with active processes of acidity generation and metal mobility. Total PTEs concentrations indicated that the mining materials were extremely polluted, with Pb, Zn and Cd geoaccumulation index (Igeo) values higher than 5 in more than 90% of the samples. The pollution load index (PLI) showed average values of 18.1, which classifies them as very highly polluted. The toxicity tests showed a higher toxicity for plants than crustaceans, being the highest values of toxicity related to toxic elements (Pb, Cd and Zn), electrical conductivity and to pH. This paper presents for the first time the combination of indices in the categorization of mining waste prior to its restoration. The combination of them has made it possible to categorize the waste and adapt the restoration and remediation procedures.

The impact of climate change drivers on cultivated plants and pest insects has come into research focus. One of the most significant drivers is atmospheric carbon dioxide, which is converted into primary plant metabolites by photosynthesis. Increased atmospheric CO2 concentrations therefore affect plant chemistry. The chemical composition of non-volatile and volatile organic compounds of plants is used by insects to locate and identify suitable host plants for feeding and reproduction. We investigated whether elevated CO2 concentrations in the atmosphere affect the plant-pest interaction in a fruit crop of high economic importance in Europe. Therefore, potted pear trees were cultivated under specified CO2 conditions in a Free-Air Carbon dioxide Enrichment (FACE) facility at Geisenheim University in Germany for up to 14 weeks, beginning from bud swelling. We compared emitted volatiles from these pear trees cultivated for 7 and 14 weeks under two different CO2 levels (ambient: ca. 400 ppm and elevated: ca. 450 ppm CO2) and their impact on pest insect behavior. In total, we detected and analyzed 76 VOCs from pear trees. While we did not detect an overall change in VOC compositions, the relative release of single compounds changed in response to CO2 increase. Differences in VOC release were inconsistent over time (phenology stages) and between study years, indicating interactions with other climate parameters, such as temperature. Even though insect-plant interaction can rely on specific volatile compounds and specific mixtures of compounds, respectively, the changes of VOC patterns in our field study did not impact the host choice behavior of C. pyri females. In olfactometer trials, 64% and 60% of the females preferred the odor of pear trees cultivated under elevated CO2 for 7 and 14 weeks, respectively, over the odor from pear trees cultivated under ambient CO2. In binary-choice oviposition assays, C. pyri females laid most eggs on pears during April 2020; on average, 51.9 (± 51.3) eggs were laid on pears cultivated under eCO2 and 60.3 (± 48.7) eggs on aCO2.

A field experiment was conducted investigating the possibility of using treated wastewater (TWW) on sites affected by water scarcity in summer, waterlogging during the wet season, and salinity. A corresponding pot experiment was conducted comparable to the field experiment in Kalaât Landelous. The same plant species (Atriplex nummularia Lindl., Eucalyptus gomphocephala DC., Acacia cyanophylla Lindl., Casuarina glauca Sieber ex Spreng., Cupressus sempervirens L., and Pinus halepensis Mill.) were grown with the same treatments. While, in the field the plants, elemental composition cannot be linked to inputs by TWW, this was studied under controlled conditions. Additionally, a control was established lower in salinity receiving tap water. The effect of TWW irrigation on macro- and microelement uptake by the six plant species was studied. The treatments were high soil salinity under drained saline (DS) conditions, high salinity under waterlogged saline (WS), and a drained non-saline control (DNS: EC = 3.0 dS/m, pH = 8.4). TWW application under DS treatment increased Na, Cl, Ca, Mg, N, P, and K in most plant tissues compared to the control. TWW application in WS treatment resulted in an increase in heavy metals. Cu and Zn showed the highest bioaccumulation factor (BAF). The BAF in different plant tissues followed the order: Cu > Zn > Mn > Cd > Ni > Co > Pb. The plants accumulated significant amounts of metals in their roots.

Wastewater treatment plants (WWTPs) have been reported as major anthropogenic reservoirs for the spread of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) into the environment, worldwide. While most studies mainly focus on the intracellular DNA (iDNA), extracellular DNA (exDNA) accounting for a significant proportion of the total DNA in wastewater, was usually neglected. Following the One Health approach, this study focuses on wastewaters of municipal, clinical, and livestock origins (n = 45) that undergo different treatment processes (i.e., conventional activated sludge, ultrafiltration, and ozonation). Water samples were analysed for 12 ARGs as indicators of the different compartments associated with iDNA and exDNA by quantitative real-time PCR (qPCR). Taxonomic profiling of exDNA-fractions, obtained using nucleic acid adsorption particles, was conducted by sequencing the V3-V4 hypervariable regions of the 16S rRNA gene. Notified exDNA concentrations varied between on-site WWTPs and treatment stages, and ranged from 314.0 ± 70.2 ng/mL in untreated livestock wastewater down to 0.7 ± 0.1 ng/mL in effluents after ultrafiltration. In general, influents exhibited higher concentrations compared to effluents, while wastewater treated by advanced treatment processes (i.e., ultrafiltration and ozonation) showed the lowest exDNA concentrations. Despite the lower concentrations, free-floating exDNA accounted for up to 80.0 ± 5.8% of the total DNA in effluents. Target ARGs were more common in the iDNA (100%, n = 45/45), compared to the exDNA-fractions (51.1%, n = 23/45), whereas exDNA-ARGs were mostly detected in clinical and slaughterhouse wastewaters as well as in the municipal influents. Compared to the iDNA-ARGs, the concentrations of exDNA-ARGs were in general lower. Nevertheless, significant higher concentrations for exDNA-associated genes were measured in clinical wastewaters for blaNDM (4.07 ± 0.15 log gene copies (GC)/L) and blaVIM-2 (6.0 ± 0.2 log GC/L). Overall, our results suggest that depending on the origin of wastewater and its treatment methods, exDNA represents an important reservoir for ARGs, particularly in clinical wastewater.

As an important part of marine litter at the seafloor “Abandoned, lost, discarded or otherwise lost fishing gear” (ALDFG) is gaining increasing attention in environmental assessments. Within this study marine litter at the seafloor of the Baltic Sea was quantified and characterized with special regard to fishery as source. Litter items (LI) were collected within fishery catches by bottom trawling during three cruises in 2020 and 2021. The resulting mean litter abundance was 9.2 LI/km2. Approximately 56 % of all LI were plastic, with PE as the most frequently identified polymer. ALDFG was present in considerable amounts with a mean value of 2.2 LI/km2 (22.2 %). However, the absolute counts of fishery nets were low (0.4 LI/km2; 4.2 %). Regarding weight, fishery nets are the dominant part of litter at the Baltic seafloor. Threshold values for marine litter at the seafloor are missing and might be developed using quantitative data on ALDFG.