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Research about California, Colorado, Idaho, Montana

Source-linked reports with geographic coverage including California, Colorado, Idaho, Montana.

2 recordsLinked to original sources

Artificial intelligence with earth observations provides continuous streamflow data across varying wildfire recurrence and recovery scenarios

Wildfires continue to alter watershed hydrology globally. Numerous studies have analyzed post-fire hydrology through before- and after-fire comparisons—often focusing on a single fire event. This has led to a significant gap in research, where continuous, daily streamflow data are needed to capture both the short- and long-term effects of recurring fires. Our study, for the first time, demonstrates how Artificial Intelligence (AI) through Machine Learning/Deep Learning (ML/DL) models can fill this gap by harnessing Earth Observations of burn severity, fire radiative power, and burn dates alongside traditional watershed attributes and drought indicators. We present a highly efficient DL model based on the Long Short-term Memory (LSTM) algorithm that is both reproducible and generalizable across multiple fire-affected watersheds in the western United States. Despite watersheds’ diverse climate conditions and markedly different hydrologic characteristics, the model consistently achieves strong performance, with Kling Gupta Efficiency ranging between 0.7 and 0.9. Our primary contribution is testing the model at a daily time-scale to model three distinct fire scenarios: no significant fire history yet the occurrence of a large fire, a longer return interval and no-fire period between phases of recurring fires, and frequent and repeated fire activity. We further investigate whether a relatively simple ML model such as Support Vector Machine (SVM) can achieve comparable accuracy in capturing these complex post-fire scenarios. By offering this fully open-source, generalizable AI solution powered by Earth Observations, newer and better modeling tools can provide post-fire daily streamflow data—a step in the right direction to safeguard water supply reliability and support watershed management across fire-prone regions worldwide.

California, Colorado, Idaho, Montana↗

Long-term monitoring reveals convergent patterns of recovery from mining contamination across 4 western US watersheds

Long-term studies of stream ecosystems are essential for assessing restoration success because they allow researchers to quantify recovery trajectories, gauge the relative influence of episodic events, and determine the time required to achieve clean-up objectives. To quantify responses of benthic macroinvertebrate assemblages to stream remediation, we integrated results of 4 long-term (20–29 y) assessments of mining-impacted watersheds that were broadly distributed across the western US (California, Colorado, Idaho, Montana). Using a before–after control–impact (BACI) study design, we observed substantial reductions in metal concentrations and corresponding improvements of benthic assemblages following remediation. Recovery rates were relatively consistent, and streams typically recovered within 10 to 15 y after remediation was initiated (mean = 10.25 y), although episodic events changed trajectories at some sites. Differences in recovery among watersheds were likely determined by a number of factors, including the severity of contamination, effectiveness of remediation, proximity to upstream sources of colonization, and hydrologic variation. We also observed considerable variation in the rate and extent of recovery among assemblage metrics. For example, total abundance and richness recovered rapidly at most sites, but the composition of benthic macroinvertebrate assemblages remained substantially altered compared with reference sites. Using piecewise linear regression, we estimated a threshold response of Ephemeroptera, Plecoptera, and Trichoptera (EPT) species richness at ~1 cumulative criteria unit (CCU), which is the sum of the fractions of chronic water-quality criteria for metals measured, suggesting this value was protective of benthic assemblages. However, EPT richness was reduced by ~20% at 2× this CCU value, indicating that moderate exceedances of water-quality criteria could substantially affect stream biodiversity. Non-metric multidimensional scaling analyses identified common sets of species trait states across the 4 watersheds that were associated with either metal contamination or with recovering and intact reference stream assemblages. Our study illustrates the importance of long-term studies for quantifying responses to stream restoration and the usefulness of BACI designs for demonstrating cause-and-effect relationships between restoration treatments and community recovery. Because these 4 watersheds were among the most severely polluted sites in the western US, our study demonstrates the value of these investments in watershed restoration and the potential for success under the most extreme conditions.

California, Colorado, Idaho, Montana↗