Response of hydrology to climate change in the southern Appalachian Mountains using Bayesian inference

Wu, Wenbin; Clark, James S.; Vose, James M.

doi:10.1002/hyp.9677

Cited by 11 publications

(10 citation statements)

References 63 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Increases in temperature and intensity of both wet and dry extremes have been documented in the southern Appalachians and in the southeastern United States Wu, Clark, & Vose, 2014) and are expected to increase with climate change (Carter et al, 2014).…”

Section: Introductionmentioning

confidence: 99%

Topography may mitigate drought effects on vegetation along a hillslope gradient

Hawthorne

Miniat

2017

Ecohydrology

View full text Add to dashboard Cite

Topography may mitigate drought effects on vegetation along a hillslope gradient through redistribution of soil moisture. We examined the interaction of topography, climate, soil moisture, and transpiration in a low-elevation, mixed-hardwood forest in the southern Appalachian Mountains.The effects of meteorological variation (wet and dry years) and topographic position (upslope and cove) were tested on daily soil moisture amplitude and recession and plot and species-specific transpiration. Trees in the cove plot were 17% taller and had 45% greater sapwood area than those in the upslope plot. Lower rates of soil moisture recession following rainfall events were observed at the cove plot compared to the upper plot. Greater daily soil moisture amplitude and plot transpiration, even in dry years, suggest that lower slope positions may have been buffered against moderate drought. We also observed similar transpiration in Quercus spp., Carya spp., and Liriodendron tulipifera in the cove plot between dry and wet years. Plot transpiration was reduced by 51% in the dry year in the upslope plot only, and transpiration by individual species in the plot reflected this pattern, suggesting water stress in dry years may be exacerbated by topography. With drought predicted to increase for these systems, the different drought responses of species, in addition to topographic effects, may lead to complex shifts in species composition.

show abstract

Section: Introductionmentioning

confidence: 99%

Topography may mitigate drought effects on vegetation along a hillslope gradient

Hawthorne

Miniat

2017

Ecohydrology

View full text Add to dashboard Cite

show abstract

“…Although streams in the southern Appalachians are considered perennial (Sun et al ., ), there are already noticeable changes to the frequency and intensity of rainfall in the region (Laseter, ; Wu et al ., , ). In this study, we demonstrated that water (as discharge) had a major influence on leaf processes in our streams.…”

Section: Discussionmentioning

confidence: 97%

“…Gessner et al, 2010). The predicted change in precipitation and generally lower flows during the summer and autumn months (Wu et al, 2012(Wu et al, , 2014 suggest that ecosystem processes may not be stimulated at a time when leaf inputs are typically maximal and stream invertebrates would have a large availability of food to fuel their production (Whiles & Wallace, 1995;Wallace et al, 1997).…”

Section: Combined Effects and The Future Of Decompositionmentioning

confidence: 99%

“…These streams are ideal because, in spite of constant stream flow, precipitation frequency and intensity are currently changing relative to past conditions. Most precipitation has shifted to winter and spring, as opposed to the more even annual distribution of rainfall in the past (Wu, Clark & Vose, , ). For example, in the last decade, the distribution of storms at Coweeta Hydrologic Laboratory in North Carolina have not only demonstrated a temporal shift away from summer but also an increase in intensity relative to those measured made during the middle of the 20th century (Ford et al ., ; Laseter et al., ).…”

Section: Introductionmentioning

confidence: 97%

See 1 more Smart Citation

Experimental reductions in stream flow alter litter processing and consumer subsidies in headwater streams

Northington

Webster

2017

Freshwater Biology

View full text Add to dashboard Cite

Summary Forested headwater streams are connected to their surrounding catchments by a reliance on terrestrial subsidies. Changes in precipitation patterns and stream flow represent a potential disruption in stream ecosystem function, as the delivery of terrestrial detritus to aquatic consumers and downstream transport are compromised. The potential effect of drying on decomposition is critical to understanding ecosystem processes in these detritus‐driven ecosystems. In this study, we experimentally altered stream connectivity to examine how altered water availability would influence litter decomposition. We used three catchments in the Coweeta Hydrologic Lab in North Carolina, U.S.A., establishing sites that were always wet, intermediately wet and completely terrestrial, while also experimentally diverting significant surface flow from downstream locations for several months. The flow manipulation significantly reduced the amount of water available to the three study reaches, leading to drastic changes in organic matter accumulation. Stream temperature and dissolved oxygen changed during the manipulation but only in response to season. Nutrient concentrations remained low or below detection during the experiment, demonstrating no response to the manipulation. Red maple and white oak demonstrated significantly different mass loss during the first few days of the experiment, but by the completion of the experiment, location was a more significant determinant of breakdown rate than leaf identity. Leaves placed in sites that were consistently wet decomposed at a higher rate than those in bank or terrestrial sites. Initially, leaf decomposition varied significantly based on site type and presence of water, which led to disruptions in microbial and macroinvertebrate colonisation and processing. High flows during large winter storms reconnected dried reaches and stimulated rates of decomposition due to colonisation by microbes and macroinvertebrates. Macroinvertebrate densities tracked microbial biomass accumulation on leaves, but were dependent upon location. Leaves in the manipulated reaches had significantly higher macroinvertebrate densities compared to the upstream control in the winter and spring in response to the delayed wetting of large standing stocks of leaves and subsequent colonisation by microbes. Our study demonstrated that even minor disruptions in stream connectivity at key times of the year have community‐ and ecosystem‐level influences that alter decomposition. The resilience of these ecosystems will depend on the frequency of disturbances and the ability of organisms to adapt to changing resource conditions.

show abstract

“…Notwithstanding, future precipitation for the region is expected to increase between 8-10% by 2100, which is similar to the 15% increases predicted for the larger eastern USA (Fernandez and Zegre 2019). Nearby regions of the northeast and southeast US are also expected to experience changes in future P, with P increasing by 3-6% by 2099 , Wu et al 2012.…”

Section: How Has Climate Changed In the Central Appalachian Mountains?mentioning

confidence: 51%

Impacts of climate and land cover on water balance components in the central Appalachian Mountains, USA

Gaertner¹

View full text Add to dashboard Cite

Impacts of climate and land cover on water balance components in the central Appalachian Mountains, USA Brandi Gaertner The purpose of this research is to investigate the impact of climate and land cover on water balance components including evapotranspiration and runoff in the mountainous central Appalachian region of the United States. Forests play a critical role in provisioning freshwater resources to downstream regions, but climate change has affected growing season lengths and water balance fluxes including precipitation, evapotranspiration, and runoff, leading to large fluctuations in water yield. The effects of climate warming are especially important in headwater basins that contribute drinking water resources to downstream population centers. The central Appalachian region is one such region that provides fresh water to approximately 9% of the U.S. population including downstream metropolitan areas such as Washington D.C., Pittsburgh (PA), Cincinnati (OH), and the Mississippi River Basin. Therefore, understanding the impacts of climate change and land use change on water balance components in headwater basins in the central Appalachian Mountains is critical for developing policies and practices that enhance future water sustainability. In order to develop a comprehensive understanding of climate and land cover on water balance components within the central Appalachian region, the research was divided into three parts. The first study analyzed trends in climatologic, hydrologic, and growing season length variables, identified the important variables effecting growing season length changes, and evaluated the influence of a lengthened growing season on increasing evapotranspiration trends. Three growing season length variables were generated using remotely sensed GIMMS NDVI3g data, two variables from measured streamflow, and 13 climate parameters from gridded datasets. Various climate, hydrology, and phenology explanatory variables were included in two applications of Principle Components Analysis to reduce dimensionality, then the final variables were utilized in two Linear Mixed Effects models to evaluate the role of climate on growing season length and evapotranspiration. The results showed that growing season length has increased, on average, by ~22 days and evapotranspiration has increased ~12 mm. The results also suggest that a suite of climatic variables including temperature, vapor pressure deficit, wind, and humidity are important in growing season length change. The climatic variables work synergistically to produce greater evaporative demand and atmospheric humidity, which is theoretically consistent with the Clausius-Clapeyron relation, which states that humidity increases nonlinearly by 7%/K. Optimization of the evapotranspiration model was increased by the inclusion of growing season length, suggesting that growing season length is partially responsible for variations in evapotranspiration over time. The results of this research imply that a longer growing season has the potential to increase...

show abstract

Response of hydrology to climate change in the southern Appalachian Mountains using Bayesian inference

Cited by 11 publications

References 63 publications

Topography may mitigate drought effects on vegetation along a hillslope gradient

Topography may mitigate drought effects on vegetation along a hillslope gradient

Experimental reductions in stream flow alter litter processing and consumer subsidies in headwater streams

Impacts of climate and land cover on water balance components in the central Appalachian Mountains, USA

Contact Info

Product

Resources

About