Conclusions:Wetlands and riparian zones should be strategically placed in watersheds to optimize nitrogen removal, as, for example, in tile-drained farmlands prone to high concentrations of nitrateThresholds/Learnings:Restoring 10 million hectares of riparian zones and wetlands, representing 3.4% of the Mississippi River basin, would reduce nitrogen in the Mississippi River Basin and its tributaries by an average of 40%
Conclusions:Water chemistry parameters sampled in downstream reaches were most closely correlated with riparian land cover adjacent to the smallest (first-order) streams of watersheds or land use in the entire watershed, with riparian zones immediately upstream of sampling sites offering less explanatory power as stream size increased.Thresholds/Learnings:
Effects of spring prescribed burning and wildfires on watershed nitrogen dynamics of central Idaho headwater areas
Conclusions: Prescribed burns did not supply the stream ecosystem with potentially important nutrient pulses that are often observed after wildfires. Prescribing higher severity burns to more closely mimic wildfires would enhance N cycling in productivity in N-limited headwater watersheds. Thresholds/Learnings: Synopsis: This study aimed to compare the short-term effects of spring prescribed burns and wildfires on Nitrogen cycling dynamics in headwater watersheds of central Idaho. Fire affected N dynamics in both terrestrial and aquatic components of the watershed ecosystem after wildfires but were limited to the terrestrial ecosystem after prescribed burns. Streamwater NO3 concentrations were affected significantly...
Conclusions:When riparian vegetation is maintained in areas of intensive agriculture, suspended solids levels are generally lower due to reduced in-stream organic production. Sediment deposition in near stream areas and stream bank scour are also reduced when riparian vegetation is present.Thresholds/Learnings:
The consequences of climate change for ecosystem structure and function remain largely unknown. Here, I examine the ability of climate variation to explain long-term changes in bird and plant populations, as well as trophic interactions in a high-elevation riparian system in central Arizona, USA, based on 20 years of study. Abundances of dominant deciduous trees have declined dramatically over the 20 years, correlated with a decline in overwinter snowfall. Snowfall can affect overwinter presence of elk, whose browsing can significantly impact deciduous tree abundance. Thus, climate may affect the plant community indirectly through effects on herbivores, but may also act directly by influencing water availability...
Indicators for Assessing Environmental Performance of Watersheds in Southern Alberta. Assessment report
Conclusions:Presents condition and pressure indicators for land, water quantity, water quality, and aquatic and riparian systems, as a series of categorized indicators of environmental quality. These broadly include: land quality condition indicators, land use pressure indicators, water quantity pressure indicators, water quality pressure indicators, and indicators of aquatic and riparian ecosystem health.Thresholds/Learnings:
Influences of watershed, riparian corridor, and reach scale characteristics on aquatic biota in agricultural watersheds.
Conclusions:Higher percentages of forest cover within the watershed and within a 30m buffer were related to healthy fish communities and water quality, while near stream grasslands and urban land cover in the watershed contributed negatively to the health of fish communities and water quality.Thresholds/Learnings:High percentages of forest cover within a 30m riparian buffer were related to healthy fish communities and water quality. Fish density increased with increase in the average length of riparian vegetation without gaps (>30m).