Time marches on, but do the causal pathways driving instream habitat and biology remain consistent?

The Science of The Total Environment, Journal Year: 2021, Volume and Issue: 789, P. 147985 - 147985

Published: May 24, 2021

Stream ecosystems are complex networks of interacting terrestrial and aquatic drivers. To untangle these ecological networks, efforts evaluating the direct indirect effects landscape, climate, instream predictors on biological condition through time needed. We used structural equation modeling leveraged a stream survey program to identify compare important driving benthic macroinvertebrate fish assemblages. data resampled 14 years apart at 252 locations across Maryland, USA. Sample covered wide range conditions that varied spatiotemporally. Overall, relationship directions were consistent between sample periods, but their relative strength temporally. For macroinvertebrates, we found total effect natural landscape (e.g., elevation, longitude, latitude, geology) land use (i.e., forest, development, agriculture) was 1.4 1.5 times greater in late 2010s compared 2000s. Moreover, water quality nitrogen conductivity) habitat embeddedness, riffle quality) 1.2 4.8 lower 2010s, respectively. assemblage condition, use-land cover 2.3 2000s, while local As expected, assemblages catchments with more agriculture urban development generally comprised tolerant, generalist species, forest had more-specialized, less-tolerant species Ephemeroptera, Plecoptera, Trichoptera taxa, clingers, lithophilic spawning fishes). Changes importance land-use suggest other correlated, yet unmeasured, proximal factors became over time. By untangling stakeholders can gain better understanding spatiotemporal relationships implement management practices aimed improving condition.

Language: Английский

Agricultural Land-Use Legacy, The Invasive Alga Didymosphenia geminata and Invertebrate Communities in Upland Streams with Natural Flow Regimes

Environmental Management, Journal Year: 2020, Volume and Issue: 65(6), P. 804 - 817

Published: March 28, 2020

Language: Английский

The Midwest Stream Quality Assessment—Influences of human activities on streams

Fact sheet, Journal Year: 2018, Volume and Issue: unknown

Published: Jan. 1, 2018

First posted April 16, 2018 For additional information, contact: National Water-Quality Assessment (NAWQA) ProjectU.S. Geological Survey413 Center12201 Sunrise Valley DriveReston, Virginia 20192 Healthy streams and the fish other organisms that live in them contribute to our quality of life. Extensive modification landscape Midwestern United States, however, has profoundly affected condition streams. Row crops pavement have replaced grasslands woodlands, been straightened, wetlands fields drained. Runoff from agricultural urban land brings sediment chemicals What is chemical, physical, biological streams? Which physical chemical stressors are adversely affecting communities, what their origins, how might we lessen or avoid adverse effects?In 2013, U.S. Survey (USGS) conducted Midwest Stream Quality evaluate human activities affect In collaboration with Environmental Protection Agency Rivers Streams Assessment, USGS sampled 100 streams, chosen be representative different types watersheds region. Biological was evaluated based on number diversity fish, algae, invertebrates Changes habitat characteristics streams—"stressors"—were assessed, relation factors explored by using mathematical models. The data models help us better understand

Language: Английский