Reviews & Analysis

Wildfires are increasing across the United States and are a growing contributor to air pollution. Combining high-resolution satellite- and ground-based data on smoke exposure with standardized test scores reveals that smoke exposure worsens school students’ learning outcomes. The costs of lowered performance are mostly borne by economically disadvantaged communities of colour.

As the pressure on Amazonian forests builds, the search for more sustainable agricultural development pathways has intensified. Access to floodplain soils can reduce pressure on upland forests and prevent them being cleared for agriculture. Floodplain farming can be a solution to enable both sustainable agriculture and forest conservation.

Hydrological modelling makes it possible to derive measures of water availability that are representative of its importance for human sustenance. This approach, and focusing on water utilization processes rather than simplifying them into environmental factors, helps identify new quantitative evidence of interconnections between conflict, society and the environment.

The cause of the sudden increase in the complexity of prehistoric societies 4,000–6,000 years ago is unknown. Pig diet and millet-field manuring studies indicate that an intensive millet–pig system developed approximately 5,500 years ago in North China, which provided food for the growing populations of the emerging complex societies.

The concentration of disinfection byproducts in tap water varies considerably across China and is statistically related to bladder cancer incidence rates. Anthropogenic factors are shown to have a notable influence on water quality. Countries and regions experiencing rapid socioeconomic development should consider adopting solutions to increase the safety of drinking water.

The link between oxygen redox and structural disorder in lithium-rich layered electrodes has been challenging to unravel. A theoretical framework for the link between structural disorder, subsequent bond rearrangements and redox chemistry has been proposed, providing guidance for the materials engineering of high-capacity electrodes.

A global analysis of stream gauges reveals that they are predominantly installed on large, perennially flowing and human-impacted rivers. The current placement of stream gauges does not provide observations that represent the wide variety of global rivers, resulting in a biased dataset, which has broad implications for ecology, hydrology, and freshwater management.