Valuation of environmental goods and services are frequently spatially heterogeneous, the significance of this heterogeneity for policy analysis is gradually recognized. For the valuation of environmental goods and services in the context of attaining a better environmental status across Heihe River basin (HRB), Northwest of China by 2020, a survey was conducted employing choice experiment approach across the entire river basin. In this research we estimate the impact of distance from inland rivers’ origin (spatial attribute) on the inhabitants’ willingness to pay for restoration of ecological attributes. A total of 11 ecological attributes were selected including 6 land related attributes and 5 water related attributes. The present study displays the outcomes of the research planned to examine differences in willingness to pay across different locations/distances. A total of five cities and 33 surround villages/townships were included to examine for location effect, while four ad hoc base distances split samples were recognized for distance effect i.e. ≤100 km, ≤200 km, ≤300 and > 300 km from rivers’ origin. The results of mixed logit model recognized that people living at different locations value the attributes differently. For instance the people of Zhangye region are willing to pay RMB 95.66 annually for improvements in biodiversity while in Gaotai the individuals’ willingness to pay (WTP) for the same attributes was RMB 45.68. Similarly, the respondents’ living nearer to the origin of river were willing to pay relatively higher amount for the upgradation in the degraded ecosystem services than the remainders. The results of willingness to pay obtained by Krinsky Robb method confirmed that the attributes quality of agricultural products and water quality were the most preferred attributes with the willingness to pay RMB 91.09 and 122.89 respectively. The significant results of willingness to pay may serve as a reference for sustainable improvements and uplifting of the degraded ecological attributes.

This study investigated the feature of phosphorus uptake by low-cost waste concrete. Adsorption isotherms, metal dissolution, influence of P concentration and temperature, as well as adsorbent regeneration were investigated. Chemical extraction, SEM, XRD, FTIR, and XPS were employed to determine the products of P sequestration. Results demonstrated that phosphate adsorption fitted the Langmuir isotherm model well, with estimated maximum phosphate adsorption capacity of 80.5 mg/g (10 °C). Of adsorbed phosphate, 72.1% could be desorbed when 0.1 M citrate buffer was used as eluant, and waste concrete could be recovered and reused for 4 times by the combination of eluting and roasting. Mechanisms including Ca/alkali dissolution, surface adsorption, and chemical precipitation are involved in the sequestration of phosphorus from wastewater by waste concrete. Weakly adsorptive phosphorus and Ca-P precipitate were the main products. P concentration was the major factor that affected P removal capacity and the product types, while temperature had certain effect at low P concentration. The dominant product was weakly adsorptive phosphorus for low P concentration at low temperature, which was substituted by Ca-P precipitate as temperature or P concentration increased. The increase of P concentration assisted both the increase of P removal potential and the formation of Ca-P precipitate to crystal DCPD.

Sediment toxicity plays a fundamental role in the health of inland fish communities; however, the assessment of the hazard potential of contaminated sediments is not a common objective in environmental diagnostics or remediation. This study examined the potential of transcriptional endpoints investigated in zebrafish (Danio rerio) exposed to riverbed sediments in ecotoxicity testing. Embryo-larval 10-day tests were conducted on sediment samples collected from five sites (one upstream and four downstream of the city of Milan) along a polluted tributary of the Po River, the Lambro River. Sediment chemistry showed a progressive downstream deterioration in river quality, so that the final sampling site showed up to eight times higher concentrations of, for example, triclosan, galaxolide, PAH, PCB, BPA, Ni, and Pb, compared with the uppermost site. The embryo/larval tests showed widespread toxicity although the middle river sections evidenced worse effects, as evidenced by delayed embryo development, hatching rate, larval survival, and growth. At the mRNA transcript level, the genes encoding biotransformation enzymes (cyp1a, gst, ugt) showed increasing upregulations after exposure to sediment from further downstream sites. The genes involved in antioxidant responses (sod, gpx) suggested that more critical conditions may be present at downstream sites, but even upstream of Milan there seemed to be some level of oxidative stress. Indirect evidences of potential apoptotic activity (bcl2/bax < 1) in turn suggested the possibility of genotoxic effects. The genes encoding for estrogen receptors (erα, erβ1, erβ2) showed exposure to (xeno)estrogens with a progressive increase after exposure to sediments from downstream sites, paralleled by a corresponding downregulation of the ar gene, likely related to antiandrogenic compounds. Multiple levels of thyroid disruption were also evident particularly in downstream zebrafish, as for thyroid growth (nkx2.1), hormone synthesis and transport (tg, ttr, d2), and signal transduction (trα, trβ). The inhibition of the igf2 gene reasonably reflected larval growth inhibitions. Although none of the sediment chemicals could singly explain fish responses, principal component analysis suggested a good correlation between gene transcripts and the overall trend of contamination. Thus, the combined impacts from known and unknown covarying chemicals were proposed as the most probable explanation of fish responses. In summary, transcriptional endpoints applied to zebrafish embryo/larval test can provide sensitive, comprehensive, and timeliness information which may greatly enable the assessment of the hazard potential of sediments to fish, complementing morphological endpoints and being potentially predictive of longer studies.

Biochar has been found to be a potentially suitable amendment for landfill cover material and agricultural soil. The addition of biochar can improve the physical (e.g., adsorption capacity) and hydrological properties (e.g., water/gas permeability) of soil. However, no experimental study is available about the effect of biochar content (BC) on the gas diffusion coefficient (DP) of soil. The present study investigated the effect of BC on DP under different degree of compaction (DOC; 85%, 90%, and 95%) and soil air contents (SAC; 5%, 10%, and 15%). It was found that DOC and BC had negligible effects on DP when SAC was low (~ 5%). In contrast, when the SAC was relatively high (~ 15%), soil with DOC of 85% had the largest DP for BC ranging from 0 to 15% (w/w). Only when the SAC was large (~ 15%), the addition of biochar generally increased DP.

As the adoption of renewable power generation technologies (RPTs) is a complex and multidimensional process influenced by a variety of factors, it provokes traction among researchers to identify these influencing factors. This study aims to investigate the impact of consumers’ intention factors on willingness to pay (WTP) for renewable energy (RE) in Pakistan. The current research has contributed through expanding the theoretical framework of the theory of planned behavior by adding two new constructs, i.e., belief about RE cost and environmental concern to better understand consumers’ intentions towards adoption or prohibition of RPTs. Findings are based on the primary data gathered from 349 residents in the five major cities of Pakistan including, Karachi, Lahore, Faisalabad, Rawalpindi, and Multan by conducting a comprehensive survey. Structural equation modeling was employed for data analysis purposes. Research results indicate that the influencing factors such as attitude, subjective norms, and perceived behavioral control positively moderate the relationship between consumer’s intention and WTP for RE, belief about RE cost has a negative effect, while environmental concern did not find to have a significant effect. Based on research findings, this study offered essential policy recommendations to fulfill the country’s energy needs on its way to a future of sustainable development.

Underground coal mining inevitably causes land subsidence, while negatively impacting land and ecological environments. This is particularly severe in coal-grain overlap areas (CGOA) in eastern China, which have high groundwater levels. Mining subsidence has substantially altered the original topography, and raised the groundwater level, which threatens grain security in the region. Therefore, it is necessary to determine the damaged farmland area in the CGOA. The traditional method to define the range of coal mining disturbance is usually based on surface subsidence. However, this fails to consider the multidimensional impacts of coal mining on the ecology, which is considered unreasonable. Therefore, this paper introduces a low-cost, fast, and non-destructive method for land damage assessment in a typical CGOA in eastern China, using maize aboveground biomass (AGB) as estimated from an unmanned aerial vehicle (UAV). There were three key results from the survey. (1) underground coal mining caused significant ecological problems in the study area, including subsidence (approximately 6 m) and the degradation of vegetation (maize AGB in a range of 192.73–1338.06 g/m²). In addition, the degradation of maize was affected by subsidence (0.61** Pearson coefficient found between the AGB and surface elevation). (2) An UAV combined with multispectral and digital cameras, allowed precise estimation of the AGB and the red-edge chlorophyII index (CIᵣₑdₑdgₑ) combined with the elevation factor had the best explanatory power using the random forest (RF) method (R² = 0.96, RMSE = 65.03 g/cm²). (3) The maize AGB could be used to assess land damage affected by underground coal mining, which accounted for 82.12% of the study area. The results of the study could provide a reference for land damage assessments in the CGOA, while also providing a guide for land reclamation and agricultural management decisions in the region.

Anammox process was regarded to be one of the vital links to achieve energy-saving or energy-producing wastewater treatment plant. In the study, an anammox reactor with the nitrogen gas circulation was constructed to culture anammox granules, and the performance, granule size distribution, and microbial community were investigated. Dissolved oxygen loading is found to be an important factor for the start-up of the anammox process, and the nitrogen removal rate of 2.12 kg N m⁻³ day⁻¹ was achieved under the average nitrogen loading rate of 2.6 kg N m⁻³ day⁻¹. The activity test showed that the highest specific anammox activity of 345.9 mg N gVSS⁻¹ day⁻¹ was achieved for granules with size of 0.5–1.0 mm. The Illumina high-throughput sequencing analysis revealed the consistent variation of Candidatus Brocadia and Denitratisoma abundance in granues of all sizes, suggesting possible synergistic mechanism between heterotrophic bacteria Denitratisoma and anammox bacteria Ca. Brocadia. Furthermore, the results indicated the reactor with the nitrogen gas circulation is an efficient strategy to start-up anammox.

In this study, a photocatalyst S-doped WO₃ was successfully synthesized by the hydrothermal method. The prepared undoped and S-doped WO₃ samples were then characterized by XRD, SEM, XPS, and UV-vis DRS. The results showed that the band gap energy of S-doped WO₃ was lower than that of the undoped WO₃, which led to a better absorption of visible light. Furthermore, the results of XPS analysis suggested that the doping with S element resulted in an increase in lattice oxygen vacancies on the surface of S-WO₃, which could effectively improve the photocatalytic activity. The photocatalytic performance of the S-WO₃ samples were evaluated by the measurement of methylene blue (MB) degradation under visible light irradiation. The experimental results demonstrated that S-doped WO₃ sample exhibited a much better photodegradation performance compared to undoped WO₃, with the maximum MB removal efficiency of 78.7% for the 5% S-WO₃ sample. Based on the above results, the mechanisms of photodegradation of MB by S-WO₃ were discussed.

High temperature melting treatment and cement solidification are technologies currently used to reduce the leaching of heavy metals in municipal solid waste incinerator (MSWI) fly ash. In this paper, to ascertain the feasibility of melting MSWI fly ash with blast furnace (BF) slag, ultra-risk MSWI(U-MSWI) fly ash having high heavy metal (Zn, Pb, Cu, and Cr) contents were blended with BF slag, then melted and quenched into water to prepare reconstructed slag. The melting and solidification behaviors, phase composition and microstructure, and heavy metal leachability of reconstructed slag were studied. In addition, to study the further solidification and utilization of reconstructed slag in cement, the compressive strength and leaching concentration of cement composites with reconstructed slag were also investigated. The results indicate that the presence of heavy metals in the U-MSWI fly ash had a little influence on the microstructure and phase composition of reconstructed slag. The leaching concentration of heavy metals in the reconstructed slag increased with the increasing of U-MSWI fly ash content, and when the content of U-MSWI fly ash was less than 50 wt%, the reconstructed slag could meet the environmental requirements. The reconstructed slag further solidified by cement could be applied to landfill and construction materials. The technology of melting reconstruction treatment with cement solidification was a technical-economical choice for the industrial treatment of U-MSWI fly ash.

Carbon dioxide (CO₂) and methane (CH₄) are the two major greenhouse gases (GHGs) in the atmosphere that contribute to global warming. Vehicle emissions on expressways cannot be neglected in the megacity Shanghai because oil accounts for 41% of the total primary energy consumption, and the expressway network carries 60% of the total traffic volume. The spatial distributions of CO₂ and CH₄ concentrations were monitored in situ on the expressways and in road tunnels using a mobile vehicle. The average CO₂ and CH₄ concentrations were 472.88 ± 34.48 ppm and 2033 ± 54 ppb on the expressways and 1308.92 ± 767.48 ppm and 2182 ± 112 ppb in the road tunnels in Shanghai, respectively. The highest CO₂ and CH₄ concentrations appeared on the Yan’an Elevated Road and the North-South Elevated Road, respectively, while their lowest values both occurred on the Huaxia Elevated Road passing through the suburban area. The hotspots of CO₂ and CH₄ were not consistent, suggesting that they have different sources. Tunnels had a “push-pull effect” on GHGs, and the traffic-congested Yan’an East Road Tunnel showed a dramatically increasing trend of GHG concentration from the entrance to the exit. This traffic-congested tunnel could accumulate a very high concentration of GHGs as well as other pollutants, which could introduce unhealthy conditions for both drivers and passengers. Significant correlations between CO₂ and CH₄ mostly appeared on the expressways and in the tunnels in Shanghai, suggesting the influences of vehicle exhaust. ΔCH₄/ΔCO₂ (the slope of the linear regression between CH₄ and CO₂) and the CH₄/CO₂ ratio could be used as indicators of vehicle exhaust sources because it increases from sources (e.g., road tunnels) to the observatories in the urban area.