Non-perennial segments of rivers undergo cycles of flowing, non-flowing and dry phases, influencing ecosystem dynamics and services across the river network. This Review describes the occurrence, ecology and future of these intermittent and ephemeral flows and highlights the importance of protecting these segments.

Kimberlites are rare volcanic rocks with unusually deep origins. This Review explores the origin and evolution of kimberlite melts and their insights into mantle composition and dynamics.

Reports of stark declines in invertebrate biomass prompted attention-grabbing news headlines about an ‘insect apocalypse’, fuelling public and scientific interest in the insect biodiversity crisis. However, substantial discussion has ensued regarding the magnitude and generality of these losses. In this Viewpoint, five researchers offer their views on the insect decline debate.

The Earth’s mantle influences many dynamic processes such as crust formation, recycling, and mantle convection. This Review describes modern isotopic methods used to characterize plume-derived basalts and therefore gain insight about the mantle’s composition.

The terrestrial biosphere stores carbon in a land carbon sink, offsetting emissions of carbon into the atmosphere. This Review demonstrates that the magnitude of the land carbon sink has increased over time, but that its stability in the future is less clear and depends on effective implementation of nature-based solutions.

Irrigation accounts for a substantial proportion of global water usage and can have biophysical and biogeochemical impacts on Earth systems. This Review outlines key irrigation–Earth system interactions, and discusses the effect of future climate and socioeconomic changes on irrigation patterns and their interaction.

Dimethylsulfide is produced in the ocean, its emission driving the formation of atmospheric aerosols that cool the climate. This Review discusses the production of dimethylsulfide, its cycling in the ocean and atmosphere, and its broader radiative effects.

Ultrahigh-temperature (UHT) metamorphism represents the most extreme thermal conditions that the continental crust is capable of sustaining at 15–55 km depth. This Review assesses the characteristics of UHT metamorphism, the tectonic mechanisms, and the implications for metamorphism in present-day orogens.

Constructed wetlands are used to remove organics and nutrients from wastewater while providing ecosystem services. This Review discusses the application, principles, and operational strategies of constructed wetlands and provides guidance on their design and maintenance.

An accompanying Collection to this Issue showcases reviews, research, and opinion articles on rifts, rifted margins and mid-ocean ridges, and highlights the hazards and unique environments these settings create.

Lithium is an essential resource for the energy transition, owing to its widespread use in rechargeable batteries. This Review describes the freshwater and chemical inputs, wastes and environmental impacts of direct lithium extraction technologies and how to manage them.

Dust influences the global energy budget through various Earth system interactions. This Review outlines these interactions, revealing a total radiative effect of -0.2 ± 0.5 Wm-2, which alongside 55±30% historical increases in dust, have contributed a radiative forcing of -0.07 ± 0.18 Wm-2.

Detection, monitoring, and prediction are essential to managing landslide risk. This Technical Review examines the use of remote sensing technology in tracking landslides and mitigating disaster.