Filters: Tags: Headwater Streams (X) > Extensions: Citation (X)
6 results (8ms)
Filters
Date Range
Types Contacts Categories Tag Types
|
There is growing evidence that headwater stream ecosystems are vulnerable to changing climate and land use, but their conservation is challenged by the need to address the threats at a landscape scale, often through coordination with multiple management agencies and landowners. A decision faced by managers of headwater systems is how to best manage stream habitats to maximize their suitability for multiple species of conservation concern, including stream salamanders and brook trout, which occur in different parts of a stream network, are affected by both the terrestrial landscape and each other, and are likely influenced by future climate change. Because streams and terrestrial habitats are linked, decisions relating...
Categories: Publication;
Types: Citation;
Tags: Data Visualization & Tools,
Headwater Streams,
Landscapes,
Multiple Decision Makers,
Northeast CASC,
Conclusions: At small spatial scales, where extirpation risks are high, landscape fragmentation will likely have long-term negative consequences on the genetic variation of individual assemblages of coastal cutthroat trout. Thresholds/Learnings: Synopsis: This study aimed to determine if coastal cutthroat trout were genetically structured within streams and to assess the effects of habitat fragmentation on coastal cutthroat trout genetic variation. Habitat fragmented by roads and other human disturbances acted as dispersal barriers, which strongly influenced coastal cutthroat trout genetic structure, diversity, and differentiation. At range-wide spatial scales, fragmentation potentially contributes to coastal cutthroat...
Categories: Publication;
Types: Citation,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Coast Range,
Conservation Genetics,
Dispersal,
Headwater streams,
Isolation,
Many headwater streams in the midwestern United States were channelized for agricultural drainage. Conservation practices are implemented to reduce nutrient, pesticide, and sediment loadings within these altered streams. The impact of these practices is not well understood because their ecological impacts have not been evaluated and the relationships between water chemistry and fishes are not well understood. We evaluated relationships between water chemistry and fish communities within channelized headwater streams of Cedar Creek, Indiana, and Upper Big Walnut Creek, Ohio. Measurements of water chemistry, hydrology, and fishes have been collected from 20 sites beginning in 2005. Multiple regression analyses indicated...
Categories: Publication;
Types: Citation;
Tags: Data Visualization & Tools,
Indiana,
Landscapes,
Northeast CASC,
Ohio,
Synopsis: This study summarized results of a comparative 15N-tracer study from a wide variety of sites throughout the United States, to derive general principles related to headwater streams and nitrogen dynamics. Standardized protocols were applied in 12 headwater streams representing a wide diversity of biomes throughout the United States. These sites were part of the Lotic Intersite Nitrogen eXperiment (LINX). The most rapid uptake and transformation of inorganic nitrogen occurred in the smallest streams. Ammonium entering these streams was removed within a few tens to hundreds of meters, primarily through assimilation by microorganisms, sorption to sediments, and nitrification. Nitrate was also removed from...
Categories: Publication;
Types: Citation,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Alaska,
Arizona,
Kansas,
Landscape fragmentation,
Michigan,
Herbaceous riparian buffers (CP 21 grass filter strips) are a widely used agricultural conservation practice in the United States for reducing nutrient, pesticide, and sediment loadings to agricultural streams. The ecological impacts of herbaceous riparian buffers on the channelized agricultural headwater streams that are common throughout the midwestern United States have not been evaluated. We sampled riparian habitat, geomorphology, instream habitat, water chemistry, fishes, and amphibians for 4 years from three channelized agricultural headwater streams without herbaceous riparian buffers and three channelized streams with herbaceous riparian buffers in central Ohio. Only seven of 55 response variables exhibited...
Categories: Publication;
Types: Citation;
Tags: Agriculture,
Amphibians,
Conservation practices,
Data Visualization & Tools,
Filter strip,
What will the rivers of the Pacific Northwest look like in the future? Will they be stable or unstable? Will the waters be cold and clear or warm and muddy? Will they have salmon or other species? These questions motivated our two-year study of climate warming effects on headwater streams draining the Cascade Mountains. Using a novel combination of snow, geohydrology, and sediment transport models we assessed the vulnerability of stream channels to changing peak streamflow. Our snow modeling shows that with just a 2°C warming, snowfall shifts to rainfall at all elevations, peak snowpacks occur over two months earlier, and snowpacks are reduced by over half of historical values. Our geohydrology modeling shows that...
Categories: Publication;
Types: Citation;
Tags: Future,
Headwater Streams,
Northwest CASC,
Rivers, Streams and Lakes,
Sediment Transport,
|
|