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Context: Land use in a catchment area is critical to understanding how human activities are impacting streams. Catchment land cover is typically quantified as proportions of land use types, but such proportions do not quantify where land use patches are relative to the stream. Objectives: This paper discusses the merit of land use position metrics for application to stream assessments. Methods and results: Landscape configuration metrics (LCMs) are often used in stream assessments to describe land use position, but we argue these metrics should be avoided due to: (1) poor description of catchment land cover; (2) inconsistency, and; (3) missing link between valley and stream. Inverse-distance-weighted metrics (IDWs) explicitly quantify the position of land use patches relative to the stream, and thus are conceptually grounded in empirical evidence that the effect of land use is inversely related to its distance from the stream. Hydrologically active IDWs (HA-IDWs) further refine IDWs by quantifying the proximity of land use to hydrologic pathways connecting a stream to its catchment. Conclusions: We recommend IDW metrics become the standard method to describe catchment land use and its effect on stream conditions and that HA-IDW metrics be used when the required data is available. [ABSTRACT FROM AUTHOR]

Rivers suffer from multiple stressors acting simultaneously on their biota, but the consequences are poorly quantified at the global scale. We evaluated the biological condition of rivers globally, including the largest proportion of countries from the Global South published to date. We gathered macroinvertebrate‐ and fish‐based assessments from 72,275 and 37,676 sites, respectively, from 64 study regions across six continents and 45 nations. Because assessments were based on differing methods, different systems were consolidated into a 3‐class system: Good, Impaired, or Severely Impaired, following common guidelines. The proportion of sites in each class by study area was calculated and each region was assigned a Köppen‐Geiger climate type, Human Footprint score (addressing landscape alterations), Human Development Index (HDI) score (addressing social welfare), % rivers with good ambient water quality, % protected freshwater key biodiversity areas; and % of forest area net change rate. We found that 50% of macroinvertebrate sites and 42% of fish sites were in Good condition, whereas 21% and 29% were Severely Impaired, respectively. The poorest biological conditions occurred in Arid and Equatorial climates and the best conditions occurred in Snow climates. Severely Impaired conditions were associated (Pearson correlation coefficient) with higher HDI scores, poorer physico‐chemical water quality, and lower proportions of protected freshwater areas. Good biological conditions were associated with good water quality and increased forested areas. It is essential to implement statutory bioassessment programs in Asian, African, and South American countries, and continue them in Oceania, Europe, and North America. There is a need to invest in assessments based on fish, as there is less information globally and fish were strong indicators of degradation. Our study highlights a need to increase the extent and number of protected river catchments, preserve and restore natural forested areas in the catchments, treat wastewater discharges, and improve river connectivity. [ABSTRACT FROM AUTHOR]