2023
Rose, JP; Kupferberg, SJ; Peek, RA; Ashton, D; Bettaso, JB; Bobzien, S; Bourque, RM; Breedveld, KGH; Catenazzi, A; Drennan, JE; Gonsolin, E; Grefsrud, M; Herman, AE; House, MR; Kluber, MR; Lind, AJ; Marlow, KR; Striegle, A; Hattem, M; Wheeler, CA; Wilcox, JT; Wiseman, KD; Halstead, BJ
Identifying drivers of population dynamics for a stream breeding amphibian using time series of egg mass counts Journal Article
In: Ecosphere, vol. 14, iss. 8, pp. e4645, 2023.
Abstract | Links | BibTeX | Tags: amphibian declines, amphibian populations, amphibians, Foothill yellow‐legged frog, population structure, stream ecosystems
@article{Rose2023,
title = {Identifying drivers of population dynamics for a stream breeding amphibian using time series of egg mass counts},
author = {JP Rose and SJ Kupferberg and RA Peek and D Ashton and JB Bettaso and S Bobzien and RM Bourque and KGH Breedveld and A Catenazzi and JE Drennan and E Gonsolin and M Grefsrud and AE Herman and MR House and MR Kluber and AJ Lind and KR Marlow and A Striegle and M Hattem and CA Wheeler and JT Wilcox and KD Wiseman and BJ Halstead},
editor = {AM Kramer},
url = {https://angelo.berkeley.edu/wp-content/uploads/sites/59/Ecosphere-2023-Rose.pdf},
doi = {10.1002/ecs2.4645},
year = {2023},
date = {2023-08-24},
urldate = {2023-08-24},
journal = {Ecosphere},
volume = {14},
issue = {8},
pages = {e4645},
abstract = {The decline in amphibian populations is one of the starkest examples of the biodiversity crisis. For stream breeding amphibians, alterations to natural flow regimes by dams, water diversions, and climate change have been implicated in declines and extirpations. Identifying drivers of amphibian declines requires long time series of abundance data because amphibian populations can exhibit high natural variability. Multiple population viability analysis (MPVA) models integrate abundance data and share information from different populations to estimate how environmental factors influence population growth. Flow alteration has been linked to declines and extirpations in the Foothill Yellow-legged Frog (Rana boylii), a stream breeding amphibian native to California and Oregon. To date, no study has jointly analyzed abundance data from populations throughout the range of R. boylii in an MPVA model. We compiled time series of egg mass counts (an index of adult female abundance) from R. boylii populations in 36 focal streams and fit an MPVA model to quantify how streamflow metrics, stream temperature, and surrounding land cover affect population growth. We found population growth was positively related to stream temperature and was higher in the years following a wet year with high total annual streamflow. Density dependence was weakest (i.e., carrying capacity was highest) for streams with high seasonality of streamflow and intermediate rates of change in streamflow during spring. Our results highlight how altered streamflow can further increase the risk of decline for R. boylii populations. Managing stream conditions to better match natural flow and thermal regimes would benefit the conservation of R. boylii populations.},
keywords = {amphibian declines, amphibian populations, amphibians, Foothill yellow‐legged frog, population structure, stream ecosystems},
pubstate = {published},
tppubtype = {article}
}
The decline in amphibian populations is one of the starkest examples of the biodiversity crisis. For stream breeding amphibians, alterations to natural flow regimes by dams, water diversions, and climate change have been implicated in declines and extirpations. Identifying drivers of amphibian declines requires long time series of abundance data because amphibian populations can exhibit high natural variability. Multiple population viability analysis (MPVA) models integrate abundance data and share information from different populations to estimate how environmental factors influence population growth. Flow alteration has been linked to declines and extirpations in the Foothill Yellow-legged Frog (Rana boylii), a stream breeding amphibian native to California and Oregon. To date, no study has jointly analyzed abundance data from populations throughout the range of R. boylii in an MPVA model. We compiled time series of egg mass counts (an index of adult female abundance) from R. boylii populations in 36 focal streams and fit an MPVA model to quantify how streamflow metrics, stream temperature, and surrounding land cover affect population growth. We found population growth was positively related to stream temperature and was higher in the years following a wet year with high total annual streamflow. Density dependence was weakest (i.e., carrying capacity was highest) for streams with high seasonality of streamflow and intermediate rates of change in streamflow during spring. Our results highlight how altered streamflow can further increase the risk of decline for R. boylii populations. Managing stream conditions to better match natural flow and thermal regimes would benefit the conservation of R. boylii populations.
2009
Godsey, Kirchner S. E.; Clow, D. W.
Concentration–discharge relationships reflect chemostatic characteristics of US catchments Journal Article
In: Hydrological Processes, vol. 23, pp. 1844–1864, 2009.
Abstract | Links | BibTeX | Tags: catchment, chemical weathering, dissolved load, Foothill yellow‐legged frog, Hydrologic Benchmark Network, solute, water quality, watershed
@article{DOI:10.1002/hyp.7315,
title = {Concentration–discharge relationships reflect chemostatic characteristics of US catchments},
author = {Kirchner S. E. Godsey and D. W. Clow},
url = {https://angelo.berkeley.edu/wp-content/uploads/sites/59/Godsey_2009_HydroPro.pdf},
doi = {DOI:10.1002/hyp.7315},
year = {2009},
date = {2009-05-07},
journal = {Hydrological Processes},
volume = {23},
pages = {1844–1864},
abstract = {Concentration–discharge relationships have been widely used as clues to the hydrochemical processes that control runoff chemistry. Here we examine concentration–discharge relationships for solutes produced primarily by mineral weathering in 59 geochemically diverse US catchments. We show that these catchments exhibit nearly chemostatic behaviour; their stream concentrations of weathering products such as Ca, Mg, Na, and Si typically vary by factors of only 3 to 20 while discharge varies by several orders of magnitude. Similar patterns are observed at the inter-annual time scale. This behaviour implies that solute concentrations in stream water are not determined by simple dilution of a fixed solute flux by a variable flux of water, and that rates of solute production and/or mobilization must be nearly proportional to water fluxes, both on storm and inter-annual timescales. We compared these catchments' concentration–discharge relationships to the predictions of several simple hydrological and geochemical models. Most of these models can be forced to approximately fit the observed concentration–discharge relationships, but often only by assuming unrealistic or internally inconsistent parameter values. We propose a new model that also fits the data and may be more robust. We suggest possible tests of the new model for future studies. The relative stability of concentration under widely varying discharge may help make aquatic environments habitable. It also implies that fluxes of weathering solutes in streams, and thus fluxes of alkalinity to the oceans, are determined primarily by water fluxes. Thus, hydrology may be a major driver of the ocean-alkalinity feedback regulating climate change.},
keywords = {catchment, chemical weathering, dissolved load, Foothill yellow‐legged frog, Hydrologic Benchmark Network, solute, water quality, watershed},
pubstate = {published},
tppubtype = {article}
}
Concentration–discharge relationships have been widely used as clues to the hydrochemical processes that control runoff chemistry. Here we examine concentration–discharge relationships for solutes produced primarily by mineral weathering in 59 geochemically diverse US catchments. We show that these catchments exhibit nearly chemostatic behaviour; their stream concentrations of weathering products such as Ca, Mg, Na, and Si typically vary by factors of only 3 to 20 while discharge varies by several orders of magnitude. Similar patterns are observed at the inter-annual time scale. This behaviour implies that solute concentrations in stream water are not determined by simple dilution of a fixed solute flux by a variable flux of water, and that rates of solute production and/or mobilization must be nearly proportional to water fluxes, both on storm and inter-annual timescales. We compared these catchments’ concentration–discharge relationships to the predictions of several simple hydrological and geochemical models. Most of these models can be forced to approximately fit the observed concentration–discharge relationships, but often only by assuming unrealistic or internally inconsistent parameter values. We propose a new model that also fits the data and may be more robust. We suggest possible tests of the new model for future studies. The relative stability of concentration under widely varying discharge may help make aquatic environments habitable. It also implies that fluxes of weathering solutes in streams, and thus fluxes of alkalinity to the oceans, are determined primarily by water fluxes. Thus, hydrology may be a major driver of the ocean-alkalinity feedback regulating climate change.