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  1. Abstract

    Artisanal and small‐scale gold mining (ASGM), a wealth‐generating industry in many regions, is nonetheless a global challenge for governance and a threat to biodiversity, public health, and ecosystem integrity. In 2019, the Peruvian government mobilized a targeted, large‐scale armed intervention against illegal ASGM, which has caused deforestation and water resource degradation in this Tropical Biodiversity Hotspot. Before the intervention, the extent of waterbodies created by mining (mining ponds) was increasing by 33%–90%/year; after, they decreased by 4%–5%/year in targeted zones. Mining activity indicators showed 70%–90% abandonment. New mining activity accelerated in nearby areas outside the targeted area (pond area increases: 42%–83%; deforestation increases +3–5 km2/year). Far from intervention zones, mining remained stable during the study period. Our analysis demonstrates that targeted, large‐scale government intervention can have positive effects on conservation by stopping illegal mining activity and shifting it to permitted areas, thereby setting the stage for governance. Continued conservation efforts must further address the impacts of informal mining while (1) limiting environmental degradation by legal mining; (2) remediating former mining areas to reduce erosion and enable reforestation or alternative uses of the landscape; and (3) sustaining such efforts, as some miners began to return to intervention areas when enforcement relaxed in 2022.

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  2. Abstract The time scale of channel recovery from disturbances indicates fluvial resiliency. Quantitative predictions of channel recovery are hampered by multiple possible recovery pathways and stable states and limited long-term observations that provide benchmarks for testing proposed metrics. We take advantage of annual channel-change measurements following Tropical Storm Irene’s 2011 landfall in New England (eastern USA) to document geomorphic recovery processes and pathways toward equilibrium. A covariate metric demonstrates that channels can adjust rapidly to ongoing boundary condition shifts, but that they adjust along a continuum of possible stable states. Moreover, the covariate equilibrium metric indicates sensitivity to warm-season high discharges that, in this region, are increasing in frequency. These data also show that the channels are resilient in that they are able to recover an equilibrium form within 1–2 yr of disturbances. 
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