Limits...
Mediating Water Temperature Increases Due to Livestock and Global Change in High Elevation Meadow Streams of the Golden Trout Wilderness.

Nusslé S, Matthews KR, Carlson SM - PLoS ONE (2015)

Bottom Line: Inside the livestock exclosure in Mulkey, we found that riverbank vegetation was both larger and denser than outside the exclosure where cattle were present, resulting in more shaded waters and cooler maximal temperatures inside the exclosure.In addition, between meadows comparisons showed that water temperatures were cooler in the ungrazed meadows compared to the grazed area in the partially grazed meadow.Our results highlight that land use can interact with climate change to worsen the local thermal conditions for taxa on the edge and that protecting riparian vegetation is likely to increase the resiliency of these ecosystems to climate change.

View Article: PubMed Central - PubMed

Affiliation: Department of Environmental Science, Policy & Management, University of California, Berkeley, California, United States of America.

ABSTRACT
Rising temperatures due to climate change are pushing the thermal limits of many species, but how climate warming interacts with other anthropogenic disturbances such as land use remains poorly understood. To understand the interactive effects of climate warming and livestock grazing on water temperature in three high elevation meadow streams in the Golden Trout Wilderness, California, we measured riparian vegetation and monitored water temperature in three meadow streams between 2008 and 2013, including two "resting" meadows and one meadow that is partially grazed. All three meadows have been subject to grazing by cattle and sheep since the 1800s and their streams are home to the imperiled California golden trout (Oncorhynchus mykiss aguabonita). In 1991, a livestock exclosure was constructed in one of the meadows (Mulkey), leaving a portion of stream ungrazed to minimize the negative effects of cattle. In 2001, cattle were removed completely from two other meadows (Big Whitney and Ramshaw), which have been in a "resting" state since that time. Inside the livestock exclosure in Mulkey, we found that riverbank vegetation was both larger and denser than outside the exclosure where cattle were present, resulting in more shaded waters and cooler maximal temperatures inside the exclosure. In addition, between meadows comparisons showed that water temperatures were cooler in the ungrazed meadows compared to the grazed area in the partially grazed meadow. Finally, we found that predicted temperatures under different global warming scenarios were likely to be higher in presence of livestock grazing. Our results highlight that land use can interact with climate change to worsen the local thermal conditions for taxa on the edge and that protecting riparian vegetation is likely to increase the resiliency of these ecosystems to climate change.

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Related in: MedlinePlus

Temperature prediction model.Relationship between weekly average temperature (WavgT) [in °C] and the daily maximal temperature (DmaxT) [in °C], observed in one probe. Each point represents the temperatures from a single day measured at a single probe, red dots are for Mulkey Meadows, green dots for Ramshaw Meadows, and blue dots for Big Whitney Meadow. The three regression lines represent the three different meadows: Mulkey (solid), Ramshaw (dashed), and Big Whitney (dotted).
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pone.0142426.g006: Temperature prediction model.Relationship between weekly average temperature (WavgT) [in °C] and the daily maximal temperature (DmaxT) [in °C], observed in one probe. Each point represents the temperatures from a single day measured at a single probe, red dots are for Mulkey Meadows, green dots for Ramshaw Meadows, and blue dots for Big Whitney Meadow. The three regression lines represent the three different meadows: Mulkey (solid), Ramshaw (dashed), and Big Whitney (dotted).

Mentions: The relationship between the weekly average temperature (WavgT) and the maximal temperature (DmaxT), i.e., the slope of the temperature prediction model (Fig 6), is the highest in Mulkey: a one-degree elevation of the weekly average temperature is predicted to result in 1.74 ± 0.02°C increase in the maximal temperature reached. This value is 0.12 ± 0.04°C higher than in Ramshaw (Mixed model, t9455 = 2.47, p < 0.05) and 0.26 ± 0.10°C higher than in Big Whitney (Mixed model, t9425 = 3.18, p < 0.01).


Mediating Water Temperature Increases Due to Livestock and Global Change in High Elevation Meadow Streams of the Golden Trout Wilderness.

Nusslé S, Matthews KR, Carlson SM - PLoS ONE (2015)

Temperature prediction model.Relationship between weekly average temperature (WavgT) [in °C] and the daily maximal temperature (DmaxT) [in °C], observed in one probe. Each point represents the temperatures from a single day measured at a single probe, red dots are for Mulkey Meadows, green dots for Ramshaw Meadows, and blue dots for Big Whitney Meadow. The three regression lines represent the three different meadows: Mulkey (solid), Ramshaw (dashed), and Big Whitney (dotted).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4643935&req=5

pone.0142426.g006: Temperature prediction model.Relationship between weekly average temperature (WavgT) [in °C] and the daily maximal temperature (DmaxT) [in °C], observed in one probe. Each point represents the temperatures from a single day measured at a single probe, red dots are for Mulkey Meadows, green dots for Ramshaw Meadows, and blue dots for Big Whitney Meadow. The three regression lines represent the three different meadows: Mulkey (solid), Ramshaw (dashed), and Big Whitney (dotted).
Mentions: The relationship between the weekly average temperature (WavgT) and the maximal temperature (DmaxT), i.e., the slope of the temperature prediction model (Fig 6), is the highest in Mulkey: a one-degree elevation of the weekly average temperature is predicted to result in 1.74 ± 0.02°C increase in the maximal temperature reached. This value is 0.12 ± 0.04°C higher than in Ramshaw (Mixed model, t9455 = 2.47, p < 0.05) and 0.26 ± 0.10°C higher than in Big Whitney (Mixed model, t9425 = 3.18, p < 0.01).

Bottom Line: Inside the livestock exclosure in Mulkey, we found that riverbank vegetation was both larger and denser than outside the exclosure where cattle were present, resulting in more shaded waters and cooler maximal temperatures inside the exclosure.In addition, between meadows comparisons showed that water temperatures were cooler in the ungrazed meadows compared to the grazed area in the partially grazed meadow.Our results highlight that land use can interact with climate change to worsen the local thermal conditions for taxa on the edge and that protecting riparian vegetation is likely to increase the resiliency of these ecosystems to climate change.

View Article: PubMed Central - PubMed

Affiliation: Department of Environmental Science, Policy & Management, University of California, Berkeley, California, United States of America.

ABSTRACT
Rising temperatures due to climate change are pushing the thermal limits of many species, but how climate warming interacts with other anthropogenic disturbances such as land use remains poorly understood. To understand the interactive effects of climate warming and livestock grazing on water temperature in three high elevation meadow streams in the Golden Trout Wilderness, California, we measured riparian vegetation and monitored water temperature in three meadow streams between 2008 and 2013, including two "resting" meadows and one meadow that is partially grazed. All three meadows have been subject to grazing by cattle and sheep since the 1800s and their streams are home to the imperiled California golden trout (Oncorhynchus mykiss aguabonita). In 1991, a livestock exclosure was constructed in one of the meadows (Mulkey), leaving a portion of stream ungrazed to minimize the negative effects of cattle. In 2001, cattle were removed completely from two other meadows (Big Whitney and Ramshaw), which have been in a "resting" state since that time. Inside the livestock exclosure in Mulkey, we found that riverbank vegetation was both larger and denser than outside the exclosure where cattle were present, resulting in more shaded waters and cooler maximal temperatures inside the exclosure. In addition, between meadows comparisons showed that water temperatures were cooler in the ungrazed meadows compared to the grazed area in the partially grazed meadow. Finally, we found that predicted temperatures under different global warming scenarios were likely to be higher in presence of livestock grazing. Our results highlight that land use can interact with climate change to worsen the local thermal conditions for taxa on the edge and that protecting riparian vegetation is likely to increase the resiliency of these ecosystems to climate change.

Show MeSH
Related in: MedlinePlus