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Anaerobic digestion (AD) is considered as a sustainable pathway to recover energy from organic wastes, but the digestive efficiency for waste activated sludge (WAS) is not as expected due to the limitations in WAS hydrolysis. This study proposes an effective strategy to simultaneously treat WAS and landfill leachate, aiming to promote WAS hydrolysis and enhance organics converting to methane. The effects of landfill leachate on the four stages (i.e., solubilization, hydrolysis, acidogenesis, and methanogenesis) of AD of WAS, as well as the effect mechanisms were investigated. Results showed that adding appropriate amounts of landfill leachate could promote the steps of solubilization, hydrolysis and acidogenesis of WAS, but had no-effect on methanogenesis. The hydrolysis and acidogenesis efficiency in the leachate added digesters were 2.0%-8.4% and 35.2%-72.7% higher than the control digester. Mechanism studies indicated that humic acid (HA) contained in the leachate was conducive to the processes of both hydrolysis and acidogenesis, but detrimental to the methanogenesis. Effects of heavy metals (HMs) on AD of WAS was also dose-dependent. Digestive performance was inhibited by excessive HMs but promoted by moderate dosages. Humic acid and metal ions tend to interact to form complexes, and thus relieve their each inhibition effects. It is also found that the stability of sludge flocs was reduced by the leachate through reducing both apparent activation energy (AAE) and median particle size (MPS) of the sludge. Microbial community and diversity results revealed that the relative abundance of microbes responsible for hydrolysis and acidogenesis increased when landfill leachate was present. This research provides a more technically and economically feasible approach to co-treating and co-utilizing WAS and landfill leachate.Urban ecosystems feature intense anthropogenic activities and environmental stressors that filter species with varying life-history traits. The traits therefore provide an essential aspect to understanding how species respond to urban environments. We conducted this study in Chongqing, a mountainous city in southwestern China, and tested the hypothesis that the velocity of urban growth can alter functional compositions of urban plant communities through selection on species' taxonomic distributions and functional traits. We found that for most traits, their values spanned a wide range across the 70 spontaneous species in this study, and seed size and leaf element composition played a key role in contributing to the functional differentiation among species. At the same time, urban growth intensity was negatively correlated with leaf N concentration, the NP ratio, and specific leaf area (SLA), and positively correlated with the leaf CN ratio. This suggests that species in urban centers are associated with an acquisitive nutrient-use strategy and may gain strong competitive strategies to be favored by greater selective pressure in those long-term urban centers. Lastly, we show that urbanization as a strong filter tends to reduce the chance of species with unique traits for the spontaneous plant communities. Our study offers insights into mechanisms through which spontaneous plant communities are filtered by urbanization with a special focus on the ecological consequences of the velocity of urban growth.The issue of environmental pollution has been recognized as a typical example of an anthropogenic activity that constitutes a global challenge coupled with the influence of climate change. This has constituted several hazards which include bioaccumulation of toxic substances, pollution of the aquatic environment, and high rate of dilapidation of soil structure and texture, health hazards, high level of imbalance in the ecosystem and a high level of toxicity in humans and the environment. Tanespimycin purchase Despite the intervention of governments, industries, researchers and relevant stakeholders, these problems remain paramount in most regions. Therefore, given the aforementioned, it is essential to identify sustainable remediation techniques, innovative knowledge on remediation strategies and clean up techniques that could help in the mitigation of all these highlighted challenges. Moreover, several studies have revealed the deleterious influence of petroleum or oil spillages resulting in irreparable environmental dilapidationllages, are discussed in this study. In conclusion, the study cautiously provides a way forward by submitting that effective research and development measures ranging from public health assessments of petroleum contamination to an all-embracing application of bioremediation technology should frequently be carried out as a matter of urgency with resilient adaptation, mollification and management of these menaces.The International Convention for the Control and Management of Ships' Ballast Water and Sediments (BWM Convention) aims to mitigate the introduction risk of harmful aquatic organisms and pathogens (HAOP) via ships' ballast water and sediments. The BWM Convention has set regulations for ships to utilise exceptions and exemptions from ballast water management under specific circumstances. This study evaluated local and regional case studies to provide clarity for situations, where ships could be excepted or exempted from ballast water management without risking recipient locations to new introductions of HAOP. Ships may be excepted from ballast water management if all ballasting operations are conducted in the same location (Regulation A-3.5 of the BWM Convention). The same location case study determined whether the entire Vuosaari harbour (Helsinki, Finland) should be considered as the same location based on salinity and composition of HAOP between the two harbour terminals. The Vuosaari harbour case study revne route assessed in the Gulf of Maine, North America also resulted in a high-risk outcome. The SRA assessment resulted in an overall weak connectivity between all ports assessed within the Gulf of the St. Lawrence, indicating that a SRA-based exemption would not be appropriate for the entire study area. In summary, exceptions and exemptions should not be considered as common alternatives for ballast water management. The availability of recent and detailed species occurrence data was considered the most important factor to conduct a successful and reliable RA. SRA models should include biological factors that influence larval dispersal and recruitment potential (e.g., pelagic larval duration, settlement period) to provide a more realistic estimation of natural dispersal.