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Highlights: [•] The work studies corrosion failure analysis of L485 pipeline in CO2 environment. [•] The corrosion scale mainly consists of FeCO3. [•] The actual corrosion rate is at the range of 1.413–1.978mm/a. [•] The Mn content of L485 steel exceeds the standard compared with API Spec 5L. [•] Corrosion undergoes the bare metal, scale-covered, reaction destruction period. [Copyright &y& Elsevier]

Abstract: In order to analyze the homogeneous discharge of air dielectric barrier discharge (DBD) under ambient conditions, three different electrode structures are used in the paper. They are aluminum plane electrode, stainless mesh electrode and pure water electrode. The electrical characteristics are obtained and compared by using Lissajous figures, the waveforms of applied voltage and discharge current and the light emission images. The results show that the discharges of the different electrode structures are all filamentary discharges mode in ambient air and the discharge intensity of pure water electrode is much weaker than the other two electrodes. [Copyright &y& Elsevier]

• SOC mineralization rate increases with increasing incubation temperature. • Soil microorganisms are preferred to mineralize ROC at higher temperature. • Soil ROC, enzyme activity and pH are primary factors controlling SOC mineralization. • SOC stored in lawn soils is less susceptible to climate warming. Green spaces in urban parks are an essential part of urban planning, not only meeting the environmental demands of urban dwellers but also absorbing greenhouse gases generated in urban regions. Mineralization of soil organic carbon (SOC) is one of the most important processes of C cycling, and links C sequestration and emission. However, few studies have been focused on SOC mineralization in urban parks, especially in scenarios involving rising temperature. Here, soils from different ages of deciduous forest (DT), evergreen forest (ET) and lawn (LN) were collected from the urban parks of Chengdu megacity. A soil incubation study (35 days) was conducted to examine SOC mineralization in three temperature regimes (15, 25, and 35 ℃), three vegetation types (DT, ET, and LN) and three vegetation ages (5, 10, and 15yr), making 27 treatments in total. Results demonstrate that increases in temperature stimulated the daily SOC mineralization rate, cumulative SOC mineralization, and mineralization intensity in the soils from urban green spaces, especially in soils under the 5-year-old plantings. Furthermore, results from principal component analysis (PCA) showed that the soil labile organic carbon (LOC) fraction, especially readily oxidizable carbon (ROC), soil enzyme activity and soil pH are the major factors influencing SOC mineralization. During the incubation, the average temperature sensitivity (Q 10) of the SOC mineralization rate at 25−35 °C was higher than at 15−25 °C (P < 0.05), indicating that more C would release from urban green spaces under a warmer climate. However, over all planting ages, the average Q 10 of SOC mineralization rate in lawn soils reduced by 1.87 %–4.04 % and 4.16 %–5.84 % relative to deciduous and evergreen forest soils, respectively. Overall, the SOC mineralization rate was ranked LN > ET > DT, while the Q 10 of the SOC mineralization rate was ranked DT > ET > LN with increasing temperatures. Moreover, the older vegetation showed lower SOC mineralization rates and higher Q 10 values. These findings imply that SOC stored in the soils under grass and young plantations are less susceptible to climate warming, although the mineralization rates are higher. By contrast, SOC in soils under trees is more susceptible to climate warming, but the mineralization rates are lower. Overall, the temperature change is more important for the SOC mineralization in forest soils and older plantation soils in urban green spaces. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new concept for utilization corn stalk by coupling anaerobic fermentation and pyrolysis. • An anaerobic fermentation step was used to further ferment corn stalk silage. • Fermented liquid feed was prepared by spontaneously fermentation. • Biochar derived from non-fermented residue showed improved physic-chemical property. • Biologically modified biochar is an effective adsorbent for Cd removal from water. The recycling of agricultural waste is a global challenge to the sustainable development of agriculture. By using corn stalks, we studied the feasibility of combining anaerobic fermentation and pyrolysis processes to produce both fermentated liquid feed and biologically modified biocharas cadmium adsorbents. Anaerobic ensiling enhanced the biodegradation of corn stalks by increasing crude protein and reducing fiber contents. After 24-h anaerobic fermentation, corn stalks silage was decomposed into the liquid filtrate and non-fermented residue. Fermented liquid feed (FLF) was prepared by storing feed and liquid filtrate (1:4.0, wt/wt) in a closed tank at 20 °C for 4 days, which showed desired properties (pH < 4.5, lactic acid bacteria greater than 9.0 lg cfu g−1, lactic acid greater than 100 mmol L-1). The non-fermented residue was pyrolyzed at 500 °C to prepare biologically modified biochar (BCB24). In comparison with pristine biochar produced from corn stalks (CB), anaerobic ensiling and anaerobic fermentation significantly increased the surface area, oxygen-containing functional groups, as well as mineral components in BCB24. The maximum sorption capacity of Cd(II) for BCB24 was 2.1 times of CB, suggesting that BCB24 is an effective adsorbent for Cd(II) removal from water. Our results indicated that coupling anaerobic fermentation and pyrolysis technology can significantly improve the efficiency of corn stalks recycling. [ABSTRACT FROM AUTHOR]

Abstract Soil acidification can negatively impact the sustainability of agricultural systems. Understanding the relationships between soil pH change and its influencing factors is critical to the maintenance of soil quality and the sustainability of land use. Based on regional observations conducted in 1981 and 2012, this study used the kriging method and an unpaired t -test to evaluate soil pH change and its influencing factors at the landscape scale of the hilly area in the Sichuan basin, China. The results show that soils in the surface layer of the study area were significantly acidified from 1981 to 2012, with a decline of 0.30 pH units. Spatially, the soil pH changes were highly variable and significant acidification only occurred in farmland soils. The declines in soil pH of farmland varied with the parent materials and soil types, and the high magnitude of soil pH decrease was closely associated with the low initial pH values and small amount of soil cation exchange capacity (CEC), suggesting the different response of the degree of soil acidification to the external factors. Base cation removal by crop straw, precipitation and nitrogen fertilization had significant impacts on soil acidification in farmland areas, and this study identified critical levels of 130 kg ha−1 yr−1, 1000 mm yr−1 and 200 kg ha−1 yr−1 for base cation removal by crop straw, precipitation and nitrogen fertilization, respectively, above which soil acidification was promoted. Moreover, a significant interaction between precipitation and nitrogen fertilizer applications was also observed, since no significant soil pH changes occurred in areas with low rainfall and nitrogen fertilizer rates, while soil acidification was significantly promoted by the combined effect of high precipitation and nitrogen fertilization levels. These results highlight the degree to which soil acidification in farmland soils depends on the crop yield, the interactions of nitrogen addition and precipitation and the buffering capacity of the different soil types and parent materials. Highlights • Soil pH declined by 0.30 units from 1981 to 2012. • Significant acidification only occurred in farmland areas. • Soil pH decline in farmland varied with parent material and soil type. • Critical levels for base cation removal by crop straw, rainfall and N application existed. • Significant interactions between precipitation and N fertilizer rates were observed. [ABSTRACT FROM AUTHOR]

Gene regulation via intragenic sequences is becoming more recognized in many eukaryotes. However, the intragenic sequences mediated gene expressions in response to environmental stimuli have been largely uncharacterized. Here, we showed that the first intron of RrKSN from the Rosa rugosa cultivar 'Purple branch' had a positive effect on RrKSN expression, and the effect depends on its position and orientation. Further analyses revealed that the four adjacent cis -elements (T)CGATT/AATCG(A) within the first intron were critical for the positive regulation, and the RrKSN promotion was significantly suppressed with mutations of these elements. These cis -elements were further evidenced as binding sites for RrARR1, the homologous of Arabidopsis type-B ARABIDOPSIS RESPONSE REGULATOR 1 (ARR1) transcription factor. The first intron-mediated RrKSN expression was enhanced with over-expressing of RrARR1 , but abolished with RrARR1 silencing in rose seedlings. Moreover, the expression difference of RrKSN between 16°C and 28°C was eliminated along with RrARR1 -silencing. Taken together, these results suggested both RrARR1 and its binding elements are required for the first intron-mediated RrKSN expression in response to varying temperatures. Therefore, our results reveal a unique intragenic regulation mechanism of gene expression by which plants perceive the signal of ambient temperature in rose. • All three RrKSN introns are capable of driving LUC expression. • The first intron has a positive effect on RrKSN expression. • The cis- elements (T)CGATT/AATCG(A) are essential for the function of the first intron. • RrARR1 is required for RrKSN transcription in response to temperature. [ABSTRACT FROM AUTHOR]

The solubility of CO 2 in aqueous solutions containing bicarbonate anion was determined at 308.15, 328.15, 368.15, and 408.15 K up to 40 MPa. In comparison with Cl − , HCO 3 − has a larger size and higher molecular weight, which leads to the opposite salting-out effect. HCO 3 − can suppress CO 2 dissolution because of equilibrium reaction between CO 2 and H 2 O to form HCO 3 − . Cooperation of the three effects leads to slightly variable solubility of CO 2 in the solution containing HCO 3 − . It is found that the Duan model can more accurately predict the CO 2 solubility at low salt concentration, while the PR–HV model shows smaller error at high salt concentration. Moreover, the solubility of CO 2 in natural ground water was measured at different temperatures and pressures, and the results verified the presented mathematical model. [ABSTRACT FROM AUTHOR]

Increasing soil petroleum hydrocarbons (PHs) pollution have caused world-wide concerns. The removal of PHs from soils mainly involves physical, chemical, biological processes and their combinations. To date, most reviews in this field based on research articles, but limited papers focused on the integration of remediation technologies from the perspective of patents. In this study, 20-years Chinese patents related to the remediation of soil PHs were comprehensively analyzed. It showed an increasing number of patent applications and the patents' quantity were positively correlated with Chinese GDP over the years, suggesting the more the economy developed the more environmental problems and corresponding solutions emerged. In addition, chemical technologies were mostly used in a combination to achieve faster and better effects, while the physical technologies were often used alone due to high costs. In all PHs remediation techniques, bacteria-based bioremediation was the most used from 2000 to 2019. Bacillus spp. and Pseudomonas spp. were the most used bacteria for PHs treatment because these taxa were widely harboring functions such as biosurfactant production and hydrocarbon degradation. The future research on joint technologies combining microbial and physicochemical ones for better remediation effect and application are highly encouraged. [Display omitted] • Patent applications are positively correlated with economic development. • Microbial technology is the most popular for soil PHs remediation. • Most of the patents used bacteria than fungi. • Bacillus and Pseudomonas spp. are most frequently used bacteria. • Archaea's patent for PHs degradation is needed but lacking. [ABSTRACT FROM AUTHOR]

Abscisic acid (ABA) play a crucial role in plant acclimation to heavy-metals stresses. Nevertheless, the effects of ABA on long-distance transport and its consequences for cadmium (Cd) accumulation are insufficiently understood. Here, we investigated the effects of ABA on the development of the whole-plant water transport pathway and implications for Cd uptake and transport to the shoot of Sedum alfredii. Exposure to Cd stimulated the production of endogenous ABA levels in the non-hyperaccumulating ecotype (NHE), but not in the hyperaccumulating ecotype (HE). Increased ABA levels in NHE significantly reduced aquaporin expressions in roots, the number of xylem vessel in stem, dimensions and densities of stomata in leaves, but induced leaf osmotic adjustment. Furthermore, the ABA-driven modifications in NHE plants showed typically higher sensitivity to ABA content in leaves compared to HE, illustrating ecotype-specific responses to ABA level. In NHE, the ABA-mediated modifications primarily affected the xylem transport of Cd ions and, at the cost of considerable water delivery limitations, significantly reduced delivery of Cd ions to shoots. In contrast, maintenance of low ABA levels in HE failed to t limit transpiration rates and maximized Cd accumulation in shoots. Our results demonstrated that ABA regulates Cd hyperaccumulation of S. alfredii through specific modifications in the water transport continuum. • Differences in ABA synthesis drive ability of S. alfredii to accumulate Cd. • Cd induced different ABA production in different ecotype of S. alfredii. • ABA regulates development of the whole plant water transport pathway of S. alfredii. • Elevated ABA level hindered Cd accumulation via impaired water status in NHE. • Maintenance of minimum ABA level promoted uptake and delivery of water and Cd in HE. [ABSTRACT FROM AUTHOR]

Pot-culture experiments were conducted to investigate the potential of microorganism-saponin assisted phytoremediation of cadmium (Cd) and benzo(a)pyrene (B[a]P) co-contaminated soil using Cd-hyperaccumulator Sedum alfredii. Results showed that B[a]P-degrading bacterium (Ochrobactrum intermedium B[a]P-16) inoculation significantly increased root (by 22.1–24.1%) and shoot (by 20.5–23.4%) biomass of S. alfredii , whereas the application of saponin had no effect on the growth of S. alfredii. The saponin solution at 2 g L−1 extracted more Cd and B[a]P than water, saponin enhanced Cd and B[a]P bioavailability in soil and thus promoted their uptake and accumulation in S. alfredii. The activity of B[a]P-16, dehydrogenase and polyphenol oxidase in co-contaminated soil was promoted by growing S. alfredii, and the application of B[a]P-16 and saponins caused a significant (P < 0.05) increase in both enzyme activities. The maximum B[a]P removal rate (82.0%) and Cd phytoextraction rate (19.5%) were obtained by co-application of S. alfredii with B[a]P-16 and saponin. The B[a]P-16 and plant promoted biodegradation were the predominant contributors towards removal of B[a]P from soil. A significant (P < 0.05) synergistic effect of B[a]P-16 and saponin on B[a]P and Cd removal efficiency was observed in this study. It is suggested that planting S. alfredii with application of B[a]P-16 and saponin would be an effective method for phytoremediation of soil co-contaminated with Cd and PAHs. Image 106219 • A novel B[a]P-degrading bacterium Ochrobactrum intermedium B[a]P-16 was identified. • Inoculation with B[a]P-16 promoted the gorwth of S. alfredii. • 2 g L−1 saponin increased Cd and B[a]P solubilization significantly. • Combined use of B[a]P-16 and saponin significantly increased B[a]P and Cd phytoremediation efficiency by S. alfredii. • B[a]P-16 and plant promoted biodegradation played predominant role in removal of B[a]P. [ABSTRACT FROM AUTHOR]

The root apex is the most active part for water and ions uptake, however, longitudinal alterations in root characteristics along root apex and consequences for metal uptake in hyperaccumulator are poorly understood. Here, we compared cadmium (Cd)-induced longitudinal alterations in root apex of two ecotypes of Sedum alfredii and assess their effects on Cd uptake. Under Cd treatment, cell death began from epidermis to the stele in non-hyperaccumulating ecotype (NHE) over time, and the number of dead cells was significantly higher than that in hyperaccumulating ecotype (HE). Cd-induced the presence of border-like cells (BLCs) surrounding the root tip of NHE prevented Cd from entering roots, however, almost no BLCs were observed in the root tip of in HE. Besides, Cd-treated NHE exhibited 76% and 52% decrease in the proportions of meristematic and elongation zone, respectively, resulting in lower Cd influx and less intensive Cd-fluorescence in these zones, as compared with HE. In the differentiation zone, Cd induced earlier initiation of root hairs (RHs), lower RHs-density, shorter RHs-length, thicker RHs-radius and less trichoblasts in NHE than those in HE. These remarkable variations led to less Cd influx and lower intensity of Cd-fluorescence in RHs of NHE than those of HE. Furthermore, decline in cell wall thickness under Cd exposure resulted in less cell-wall-bond Cd in the cell wall of HE. Therefore, Cd-induced alterations in root characteristics alongside root apex contributed to the difference in Cd uptake and accumulation between two ecotypes of S. alfredii. Image 1 • HE showed higher cell viability in root apex than NHE under Cd exposure. • The presence of BLCs prevented Cd from entering roots in NHE. • Cd-induced decrease in the proportion of meristematic and elongation zone led to less free Cd2+ in NHE. • Cd exposure shortened root hairs and decreased trichoblasts in NHE thus reduced free Cd2+ in root hairs. • The thinner cell wall thickness under Cd exposure resulted in less Cd combination in the cell wall of HE. [ABSTRACT FROM AUTHOR]