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This study aimed to investigate the mechanism of sustainable biodegradation of long-alkanes with moderate pre-oxidation in soil. Moderate pre-oxidation was performed with two consecutive doses of 1.35 mL 30% of H2O2 (225 mM) in two soil. After moderate pre-oxidation, the experiment of sustainable biodegradation of long-alkanes during 80 d was conducted. Then, long-alkanes relative activity coefficient (K), NH4+-N allocation (G) and the performance of hydrocarbon degraders (E) was calculated. Long-alkanes were sustainably biodegraded with moderate pre-oxidation (1765 mg/kg, 2438 mg/kg and 2672 mg/kg). Long-alkanes biodegradation (8723 mg/kg) with moderate pre-oxidation was 2.5 folds of excessive pre-oxidation. The average increment in long-alkanes biodegradation with moderate pre-oxidation was 30–38% as K values improved (0.28–0.48). The bacterial destruction D decreased to 14–17% and hydrocarbon degraders activity increased to 0.065 mol CO2/kg with moderate pre-oxidation. Basidiomycota and Acinetobacter sp. showed high tolerance with moderate pre-oxidation and remained dominant strains throughout the bioremediation. NH4+-N consumption played an essential role as nutrients in growth of hydrocarbon degraders (Basidiomycota and Acinetobacter sp.). Then, high and sustained E was achieved with decreased D and elevated hydrocarbon degraders activity, resulting in high K. So, long-alkanes sustainably increasing biodegraded under high E assisted with elevated G with moderate pre-oxidation. [ABSTRACT FROM AUTHOR]

A high rate of elemental sulfur (S0) accumulation from sulfide-containing wastewater has great significance in terms of resource recovery and pollution control. This experimental study used Thiobacillus denitrificans and denitrifying bacteria incorporated with signal molecules (C6 and OHHL) for simultaneous sulfide (S2–) and nitrate (NO3–) removal in synthetic wastewater. Also, the effects on S0 accumulation due to changes in organic matter composition and bacteria proportion through signal molecules were analyzed. The 99.0% of S2– removal and 99.3% of NO3– was achieved with 66% of S0 accumulation under the active S2– removal group. The S0 accumulation, S2– and NO3– removal mainly occurred in 0–48 h. The S0 accumulation in the active S2– removal group was 2.0-6.3 times higher than the inactive S2– removal groups. In addition, S0/SO42- ratio exhibited that S0 conversion almost linearly increased with reaction time under the active S2– removal group. The proportion of Thiobacillus denitrificans and H+ consumption showed a positive correlation with S0 accumulation. However, a very high or low ratio of H+/S0 is not suitable for S0 accumulation. The signal molecules greatly increased the concentration of protein-I and protein-II, which resulted in the high proportion of Thiobacillus denitrificans. Therefore, high S0 accumulation was achieved as Thiobacillus denitrificans regulated the H+ consumption and electron transfer rate and provided suppressed oxygen environment. This technology is cost-effective and commercially applicable for recovering S0 from wastewater. [ABSTRACT FROM AUTHOR]

In recent years, RS and GIS technologies have played an increasingly important role in various aspects of rainfall induced landslide research. In order to systematically understand their application situation, this paper extensively used various visualization analysis technologies for in-depth analysis of 1,161 documents collected by the WOS data platform in the past 27 years by combining quantitative and qualitative methods. Then, this article focuses on sub domain analysis from four aspects: landslide detection and monitoring, prediction models, sensitivity mapping, and risk assessment. The study found that the number of literature in this field has steadily increased and is expected to continue to rise. This literature review has attracted widespread attention from the academic community, but it is challenging to meet research needs. Frequent and effective cooperation between countries, institutions, and authors is very beneficial for promoting progress in this field. The future development direction is a new intelligent hybrid model that integrates multiple research methods. This study can provide researchers in this field with the core research force, hot topic evolution, and future development trends of future rainfall-induced landslides and contribute to landslide prevention and control decision-making and achieving the United Nations'sustainable development goals. [ABSTRACT FROM AUTHOR]

Crop residue, the largest product of agricultural harvests, contains large amounts of assimilated carbon (C) and nutrients such as nitrogen (N), phosphorus (P), and potassium (P); these elements must be recycled for the sustainable development of agriculture. Crop residue management should serve a double function, both confronting global warming and food security by increasing carbon sequestration in agriculture and increasing grain yields. Historically, the North China Plain has experienced different crop residue management practices. While direct burning in the field remains an environmental problem in the region, crop residue amendment triggers benign cycling of C and nutrients in agriculture. Data showed that soil organic carbon (SOC) in topsoil increased by 0.174 to 1.74 g kg-1, with an average of 0.79 g kg-1 after wheat residue amendment collected from 35 sites in the North China Plain. The average increase in grain yield achieved by wheat residue amendment in the region is 260 kg ha-1 year-1 for wheat and 310 kg ha-1 year-1 for maize, for a total of 570 kg ha-1 year-1. At the same time, the available potassium (K2O), the available phosphorus (P2O5), and total nitrogen in soil increased, significantly or not. With the development of the economy, technology, and supporting policy, crop residue management can play an increasingly important role in sustainable agricultural development. [ABSTRACT FROM AUTHOR]