Reviews & Analysis

Whether on a hike, in a remote disaster zone or in your own home, access to clean water is critical. Filtration of freshwater to remove ultrafine particles like micro/nanoplastics, pathogens or other toxic components is unfortunately usually quite expensive, unportable and environmentally unfriendly.

International policy is concerned about palm oil-induced deforestation, whereas Indonesia’s government and industry representatives emphasize the role that palm oil plays in support of the livelihoods of millions of smallholder local farmers. This Perspective discusses how smallholders can still be supported without incurring further forest loss.

The nitritation process, namely the biological conversion of ammonia to nitrite, is a pivotal approach in sustainable sewage management but remains challenging to implement in practice. Now a strategy shows remarkable efficiency in swiftly initiating and maintaining sewage nitritation, even under industrially relevant conditions.

The development of electrocatalysts with high activity, selectivity and stability for seawater electrolysis remains a challenge. Through engineering of the host layer, interlayer gallery and surface, CoFe-based layered double hydroxides are shown to achieve stable seawater electrolysis for more than 2,800 h at a high current density.

Although carboxylated cellulose nanofibres (C-CNFs) hold promise for numerous applications, current production methods are associated with environmental concerns. A type of deep eutectic solvent, comprising citric acid, choline chloride and water, has now been developed for the sustainable and scalable production of ultrafine and long C-CNFs.

Risks in globally interconnected socio-environmental systems are complex and efforts to study them are incomplete. This Perspective argues that risks should be considered as both a product of these systems and a force that rewires them through a variety of mechanisms.

Eco-sensitive river basins are facing pressure to reduce carbon emissions and rapidly grow their economies. Now, a study identifies the exploitable hydropower potential in low-carbon futures, and the risks of relying on large-scale hydropower projects to integrate variable renewable energy in a decarbonized world.

Translating Earth system boundaries across scale involves scientific and normative judgements, with associated assumptions, bias and uncertainties. A protocol involving key building blocks and control steps in translation is presented with focus on businesses and cities, two understudied critical actors.

Adopting technological solutions for water management without considering the complexity underlying human–water interactions can result in unintended consequences. Now a systems meta-model offers a tool to reveal critical human–water links and guide coordinated solutions for sustainable water management.

Human changes to freshwater flows affect marine ecosystems, but such impacts are rarely considered in development plans involving dam building and water abstraction from rivers. Now research shows how approaches that integrate flow management and marine fisheries can improve both freshwater and coastal ecosystem sustainability.

Quantifications of the impacts of sea-level rise in small island states are urgently needed. Focusing on flooding from sea-level rise, a study now estimates the impacts in terms of cost, land loss and population exposure across all small islands worldwide.

Humans and mangroves adapt to conditions arising from subsidence and relative sea-level rise. Quantifying adaptation responses provides an innovative and cost-effective means of characterizing spatial variation in subsidence and relative sea-level rise and delivers critical information for coastal planning.

Heatwaves are more frequent and lead to considerable suffering, especially among the poorest and most disadvantaged people. This Perspective discusses the concept of systemic cooling poverty with the aim of informing policy and practice to support vulnerable groups.

Siloed exploitation, management and planning of the oceans have resulted in escalating damage to ocean biodiversity and conflicts among users. A study now provides a set of principles to ensure participation and inclusion of all rights-holders and stakeholders towards transformative ocean governance to enable sustainability.

Contemporary plastics upcycling methods rely on the use of hydrogen and solvents, which make the process not environmentally friendly. Now a solvent- and hydrogen-free strategy can convert high-density polyethylene into separable hydrocarbons with high efficiency.

Rangelands provide critical ecosystem and societal services and are central to livestock husbandry across the United States. How these considerations are balanced, and possibly expanded on, will shape the future of rangeland ecosystems and communities moving into the future.

Bisphenol A (BPA) is an industrial chemical produced in large quantities for use primarily in the manufacturing of plastics. However, its adverse effects on human health are driving the development of safer and more sustainable alternatives. Now, a synthetic route enables such an alternative, starting from renewable lignin biomass.

Air quality improvement has benefitted large portions of forests in the USA over the past 20 years. However, although terrestrial ecosystems are now better protected, sensitive species still experience harmful impacts, which could lead to biodiversity loss through shifts in forest composition.

A data-driven framework has been developed to assess the carbon emissions of mobile networks in China, revealing that the launch of 5G networks leads to a decline in carbon efficiency. A deep reinforcement learning algorithm, DeepEnergy, is proposed to increase the carbon efficiency of mobile networks and reduce carbon emissions.

Addressing the global water crisis requires technologies suited to harvest alternative sources of freshwater. Now, a bifunctional fog harvester offers a promising avenue for concurrent water collection and decontamination.