Nature-based bioreactors: Tackling antibiotic resistance in urban wastewater treatment

The overuse and misuse of antibiotics have accelerated the selection of antibiotic-resistant bacteria,significantly impacting human,animal,and environmental health.As aquatic environments are vulnerable to antibiotic resistance,suitable management practices should be adopted to tackle this phenomenon.Here we show an effective,nature-based solution for reducing antibiotic resistance from actual wastewater.We utilize a bioreactor that relies on benthic(biofilms)and planktonic microbial communities to treat secondary effluent from a small urban wastewater treatment plant(<10,000 population equivalent).This treated effluent is eventually released into the local aquatic ecosystem.We observe high removal efficiency for genes that provide resistance to commonly used antibiotic families,as well as for mobile genetic elements that could potentially aid in their spread.Importantly,we notice a buildup of sulfonamide(sul1 and sul2)and tetracycline(tet(C),tet(G),and tetR)resistance genes specifically in biofilms.This advancement marks the initial step in considering this bioreactor as a nature-based,cost-effective tertiary treatment option for small UWWTPs facing antibiotic resistance challenges.

Natural climate solutions.The way forward

Climate change is a global challenge that threatens global ecological security and sustainable development.Find-ing ways to mitigate their impacts is paramount through engineering carbon storage,low-carbon energy tran-sition,or natural climate solutions(NCS).NCS involve a set of measures(e.g.,afforestation,land restoration,biochar reuse or sustainable land use practices).Implementing NCS increases carbon sequestration and mitigates climate change at the lowest costs and greenest ways.In addition,NCS practices can improve multiple ecosystem services(ES)such as air quality,flood and erosion regulation,pest control,water purification,wild food biomass,recreation or landscape aesthetics.However,unsustainable implementation of NCS,such as over-afforestation of dense mono-forest,can lead to tradeoffs with water supply,wildfire risk,and decreased grasslands and crop-lands.Therefore,to optimise the NCS implementation,reducing the tradeoffs associated and transforming the“expand ecosystem area”to“improve ecosystem management efficiency”is vital.Although NCS can contribute significantly to mitigating climate change,systematic climate actions must be accompanied by a transformation in the global society and investment in new technologies.This will be key to addressing global challenges such as the achievement of Sustainable Development Goals(SDGs),such as SDG 13(Climate Action),SDG 15(Life on Land),SDG 2(Zero Hunger),SDG 3(Good Health and Wellbeing),SDG 6(Clean Water and Sanitation),and SDG 14(Life Bellow Water).

The Russian‐Ukrainian armed conflict will push back the sustainable development goals

The Russian-Ukrainian armed conflict is a dramatic world event. Apart from the loss of life, the present conflicthas tremendous impacts on the environment, economy, and society. The conflict provoked a ripple of events withimplications at the global level, especially in energy and food. The escalation of this conflict is imposing severethreats to achieving the United Nations (UN) Sustainable Development Goals (SDGs) not only to the countries di-rectly involved in the conflict but also to other countries, especially the developing ones that are more vulnerableto the economic crisis. In this editorial, we assessed the impacts of the Russian-Ukrainian conflict on BiophysicalSDGs, Social SDGs, Economic SDGs and Partnership for the Goals SDG that consider all the previous dimensions.The Russian-Ukrainian conflict’s impact on the SDGs is variable. Biodiversity SDGs are mainly affected at theregional level (Russia, Ukraine, surrounding and European Union countries). Society SDGs are affected at local(e.g., SDG3 good health and wellbeing;SDG4 quality education) and global (e.g., SDG2 zero hunger) levels. Fi-nally, the Russian-Ukrainian armed conflict has world-level implications for the economic SDGs. Nevertheless,the ongoing conflict’s impacts are not entirely understood, and several uncertainties exist. Peace is needed toachieve the UN’s SDGs in 2030.

Unraveling the interaction between soil microbiomes and their potential for restoring polluted soils

Soils are not exempt from anthropogenic pollution,which can eventually cause disturbance of the microbial communities and areas without any kind of productivity.Among soil microbiota,bacteria play an important role in pollutant degradation,enabling them to thrive in contaminated sites.Given this,several techniques have been used to increase the number of pollutantdegrading bacteria in situ or for subsequent addition.Additionally,bacteriophages exhibit a high tolerance to pollutants and enhance bacterial metabolic activity through phage-encoded auxiliary metabolic genes(AMGs),thereby augmenting their skills for nutrient assimilation,resistance to phage infection,antibiotic resistance,heavy metal resistance,and degradation of pesticides and xenobiotics,among others.Several phage-encoded AMGs have been described during the last few years,but their diversity,distribution,and function have not been extensively explored,warranting further studies.Here,we highlight soil microbiome interactions,especially bacterium and phage interactions to understand this unexplored world with a high potential for restoring polluted soils.

Toxicity assessment of polyethylene microplastics in combination with a mix of emerging pollutants on Physalaemus cuvieri tadpoles

Studies in recent years have shown that aquatic pollution by microplastics(MPs)can be considered to pose additional stress to amphibian populations.However,our knowledge of how MPs affect amphibians is very rudimentary,and even more limited is our understanding of their effects in combination with other emerging pollutants.Thus,we aimed to evaluate the possible toxicity of polyethylene MPs(PE-MPs)(alone or in combination with a mix of pollutants)on the health of Physalaemus cuvieri tadpoles.After 30 days of exposure,multiple biomarkers were measured,including morphological,biometric,and developmental indices,behavioral parameters,mutagenicity,cytotoxicity,antioxidant and cholinesterase responses,as well as the uptake and accumulation of PE-MPs in animals.Based on the results,there was no significant change in any of the parameters measured in tadpoles exposed to treatments,but induced stress was observed in tadpoles exposed to PE-MPs combined with themixture of pollutants,reflecting significant changes in physiological and biochemical responses.Through principal component analysis(PCA)and integrated biomarker response(IBR)assessment,effects induced by pollutants in each test group were distinguished,confirming that the exposure of P.cuvieri tadpoles to the PE-MPs in combination with a mix of emerging pollutants induces an enhanced stress response,although the uptake and accumulation of PE-MPs in these animalswas reduced.Thus,our study provides newinsight into the danger to amphibians of MPs coexisting with other pollutants in aquatic environments.