Combined effects of biological control of an invasive shrub and fluvial processes on riparian vegetation dynamics

Shafroth, Patrick B.; Lee, Steven R.; Ostoja, Steven M.; Brooks, Matthew L.

doi:10.1007/s10530-020-02259-9

Cited by 13 publications

(10 citation statements)

References 53 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Their maps show no beetles on the LCR south of Lake Mead in our study area in 2013, but show beetle presence in 2014 (https://riversedgewest.org/sites/default/files/images/Tamarisk_Coalition_20 13_TLB_Distribution_Map_Final.pdf, accessed on 24 February 2021). Recent research also shows the impact of defoliation from the salt cedar beetle on water use in nearby areas [134,135,137]. The years between 2014 and 2020 with active beetles and high levels of defoliation have contributed to our results of declining riparian greenness and water use.…”

Section: Strengths and Limitationsmentioning

confidence: 79%

“…Our results over the past two decades using Landsat time series data on the LCR riparian corridor provide the first comprehensive look at biocontrol impacts on the non-native species salt cedar health and its water use on the LCR. This study also shows timely new information in response to the pressures and concerns over available water and drought factors [134,135]. This important time series data regarding the health of this ecosystem and its water use is necessary for managers to understand the consequences of drought and biocontrol and to plan for disturbances in the future.…”

Section: Remotely Sensed Findings and Their Implicationsmentioning

confidence: 81%

“…We expect there to be benefits of PAM ET in riparian ecosystems in other river basins with non-arid/semi-arid climate regions because using daily ET and multiplying by dates of interest does not capture the type of landscape change that unrestored, natural riparian areas undergo with sudden land clearing, re-sprouting of green leaves post-fire and post-defoliation, for example. We do recognize that in this region, the daily ET estimated from only the peak growing season when reported for the full year would produce overestimates based on existing literature [116,[135][136][137]. For this reason, in this study, we report both the daily ET and the annualized PAM ET and do not use the peak growing season ET values for the full year.…”

Section: Strengths and Limitationsmentioning

confidence: 98%

See 2 more Smart Citations

Riparian Area Changes in Greenness and Water Use on the Lower Colorado River in the USA from 2000 to 2020

et al. 2021

View full text Add to dashboard Cite

Declines in riparian ecosystem greenness and water use have been observed in the delta of the Lower Colorado River (LCR) since 2000. The purpose of our case study was to measure these metrics on the U.S. side of the border between Hoover and Morelos Dams to see if declining greenness was unique to the portion of the river in Mexico. In this case study, five riparian reaches of the LCR from Hoover to Morelos Dam since 2000 were studied to evaluate trends in riparian ecosystem health. We measure these riparian woodlands using remotely sensed measurements of the two-band Enhanced Vegetation Index (EVI2; a proxy for greenness); daily evapotranspiration (ET; mmd−1) using EVI2 (ET(EVI2)); and an annualized ET based on EVI2, the Phenology Assessment Metric (PAM ET), an annualized ET using Landsat time-series. A key finding is that riparian health and its water use has been in decline since 2000 on the U.S. portion of the LCR, depicting a loss of green vegetation over the last two decades. EVI2 results show a decline of −13.83%, while average daily ET(EVI2) between the first and last decade had a decrease of over 1 mmd−1 (−27.30%) and the respective average PAM ET losses were 170.91 mmyr−1 (−17.95%). The difference between the first and last five-year periods, 2000–2005 and 2016–2020, showed the largest decrease in daily ET(EVI) of 1.24 mmd−1 (−32.61%). These declines come from a loss in healthy, green, riparian plant-cover, not a change in plant water use efficiency nor efficient use of managed water resources. Our results suggest further deterioration of biodiversity, wildlife habitat and other key ecosystem services on the U.S. portion of the LCR.

show abstract

Section: Strengths and Limitationsmentioning

confidence: 79%

Section: Remotely Sensed Findings and Their Implicationsmentioning

confidence: 81%

Section: Strengths and Limitationsmentioning

confidence: 98%

See 1 more Smart Citation

Riparian Area Changes in Greenness and Water Use on the Lower Colorado River in the USA from 2000 to 2020

et al. 2021

View full text Add to dashboard Cite

show abstract

“…2018; González, Shafroth, Lee, Ostoja, et al. 2020; González, Shafroth, Lee, Reed, et al. 2020) mimicking canopy density reduction events described by Tague et al.…”

Section: Discussionmentioning

confidence: 94%

“…The tamarisk beetle (Diorhabda spp.) has defoliated large swaths of riparian corridors in the southwestern U.S. (Nagler et al 2012(Nagler et al , 2014Nagler, Nguyen, et al 2018;Gonz ález, Shafroth, Lee, Ostoja, et al 2020;Gonz ález, Shafroth, Lee, Reed, et al 2020) mimicking canopy density reduction events described by Tague et al (2019). and Nagler, Nguyen, et al (2018) used remote sensing to measure before and after landscape-level ET in riparian areas that experienced defoliation by the tamarisk beetle (a canopy density reduction event).…”

Section: Measurements Of the Delta's Riparian Corridormentioning

confidence: 99%

Effect of Restoration on Plant Greenness and Water Use in Relation to Drought in the Riparian Corridor of the Colorado River Delta

Nagler

Sall

Barreto‐Muñoz

et al. 2022

J American Water Resour Assoc

View full text Add to dashboard Cite

The unrestored delta riparian corridor continues to decline in EVI2 and ET but restoration has positively impacted habitats and contributed to the understanding of the continuing efforts of Minute 323.ABSTRACT: Revitalization of the Colorado River delta riparian corridor and increasing riparian plant greenness and water use may be accomplished by added water and restoration efforts to offset declines measured since 2000 by Landsat. We use the two-band Enhanced Vegetation Index (EVI2; a proxy for greenness) and evapotranspiration (ET, mm/day) using EVI2 and potential ET(ETo) from Yuma Valley. We assess if restoration with only 7.5% landcover had an impact on the unrestored reach-level landcover by measuring these two metrics, EVI2 and ET(EVI2) by comparing restored and unrestored areas. A key finding is that over 21-years EVI2 in the unrestored corridor decreased by 23.6% and ET(EVI2) decreased by 32% (0.87 mm/day). Since 2011, the unrestored reaches lost EVI2 (11%) and −0.73 mm/day ET(EVI2) (28%), but restored sites increased in EVI2 (36%) and 0.58 mm/day ET(EVI2) (20%). Water delivered to restored sites increased EVI2 by 33.6% and 1.29 mm/day ET(EVI2) (58%). EVI2 and ET(EVI2) as a function of the Standardized Precipitation Evapotranspiration Index for drought periods highlight that restored and unrestored sites respond differently. Unrestored reaches are in decline; restored sites show increases in EVI2 and ET(EVI2). Restored sites do not have a significant impact on unrestored adjacent area, but smaller surface flows, a greater reliance on directed agricultural return flows, and deliveries of water to active restoration sites have revitalized habitat and increased ecosystem services in the delta.

show abstract

Provenance, genotype, and flooding influence growth and resource acquisition characteristics in a clonal, riparian shrub

Palmquist

Ogle

Whitham

et al. 2023

American J of Botany

Self Cite

View full text Add to dashboard Cite

Premise Riparian plants can exhibit intraspecific phenotypic variability across the landscape related to temperature and flooding gradients. Phenotypes that vary across a climate gradient are often partly genetically determined and may differ in their response to inundation. Changes to inundation patterns across a climate gradient could thus result in site‐specific inundation responses. Phenotypic variability is more often studied in riparian trees, yet riparian shrubs are key elements of riparian systems and may differ from trees in phenotypic variability and environmental responses. Methods We tested whether individuals of a clonal, riparian shrub, Pluchea sericea, collected from provenances spanning a temperature gradient differed in their phenotypes and responses to inundation and to what degree any differences were related to genotype. Plants were subjected to different inundation depths and a subset genotyped. Variables related to growth and resource acquisition were measured and analyzed using hierarchical, multivariate Bayesian linear regressions. Results Individuals from different provenances differed in their phenotypes, but not in their response to inundation. Phenotypes were not related to provenance temperature but were partially governed by genotype. Growth was more strongly influenced by inundation, while resource acquisition was more strongly controlled by genotype. Conclusions Growth and resource acquisition responses in a clonal, riparian shrub are affected by changes to inundation and plant demographics in unique ways. Shrubs appear to differ from trees in their responses to environmental change. Understanding environmental effects on shrubs separately from those of trees will be a key part of evaluating impacts of environmental change on riparian ecosystems.

show abstract

Combined effects of biological control of an invasive shrub and fluvial processes on riparian vegetation dynamics

Cited by 13 publications

References 53 publications

Riparian Area Changes in Greenness and Water Use on the Lower Colorado River in the USA from 2000 to 2020

Riparian Area Changes in Greenness and Water Use on the Lower Colorado River in the USA from 2000 to 2020

Effect of Restoration on Plant Greenness and Water Use in Relation to Drought in the Riparian Corridor of the Colorado River Delta

Provenance, genotype, and flooding influence growth and resource acquisition characteristics in a clonal, riparian shrub

Contact Info

Product

Resources

About