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1. Garnet crystallization does not drive oxidation at arcs

   https://doi.org/10.1126/science.ade3418  

   Holycross, Megan; Cottrell, Elizabeth (May 2023, Science)

   Garnet formation cannot be the main reason for some important features of arc lavas. 

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2. Chaos does not drive lower synchrony for intrinsically-induced population fluctuations

   https://doi.org/10.1016/j.ecolmodel.2022.110203  

   Grosklos, Guenchik; Zhao, Jia (January 2023, Ecological Modelling)
3. Insights from watershed simulations around the world: Watershed service-based restoration does not significantly enhance streamflow

   https://doi.org/10.1016/j.gloenvcha.2019.101938  

   Dennedy-Frank, P. James; Gorelick, Steven M. (September 2019, Global Environmental Change)
4. Nonlinear Riparian Interactions Drive Changes in Headwater Streamflow

   https://doi.org/10.1029/2023WR034870  

   Newcomb, Sarah K.; Godsey, Sarah E. (September 2023, Water Resources Research)

   Abstract As drought and wildfire frequency increase across the western United States, our ability to predict how water resources will respond to these disturbances depends on our understanding of the feedbacks that maintain watershed function and streamflow. Previous studies of non‐perennial headwater streams have ranked drivers of low‐flow conditions; however, there is a limited understanding of the interactions between these drivers and the processes through which these interactions affect streamflow. Here, we use stream water level, soil moisture, sap flow, and vapor pressure deficit data to investigate ecohydrological interactions along a mountainous headwater stream. Correlation and cross‐correlation analyses of these variables show that ecohydrological interactions are (a) nonlinear and (b) interconnected, suggesting that analyses assuming linearity and independence of each driver are inadequate for quantifying these interactions. To account for these issues and investigate causal linkages, we use convergent cross‐mapping (CCM) to characterize the feedbacks that influence non‐perennial streamflow. CCM is a nonlinear, dynamic method that has only recently been applied to hydrologic systems. CCM results reveal that atmospheric losses associated with local sap flow and vapor pressure deficit are driving changes in soil moisture and streamflow (p < 0.01) and that atmospheric losses influence stream water more directly than shallow soil moisture. These results also demonstrate that riparian processes continue to affect subsurface flows in the channel corridor even after stream drying. This study proposes a nonlinear framework for quantifying the ecohydrologic interactions that may determine how headwater streams respond to disturbance. 

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5. Exploring Environmental Factors That Drive Diel Variations in Tree Water Storage Using Wavelet Analysis

   https://doi.org/10.3389/frwa.2021.682285  

   Harmon, Ryan E.; Barnard, Holly R.; Day-Lewis, Frederick D.; Mao, Deqiang; Singha, Kamini (August 2021, Frontiers in Water)

   Internal water storage within trees can be a critical reservoir that helps trees overcome both short- and long-duration environmental stresses. We monitored changes in internal tree water storage in a ponderosa pine on daily and seasonal scales using moisture probes, a dendrometer, and time-lapse electrical resistivity imaging (ERI). These data were used to investigate how patterns of in-tree water storage are affected by changes in sapflow rates, soil moisture, and meteorologic factors such as vapor pressure deficit. Measurements of xylem fluid electrical conductivity were constant in the early growing season while inverted sapwood electrical conductivity steadily increased, suggesting that increases in sapwood electrical conductivity did not result from an increase in xylem fluid electrical conductivity. Seasonal increases in stem electrical conductivity corresponded with seasonal increases in trunk diameter, suggesting that increased electrical conductivity may result from new growth. On the daily scale, changes in inverted sapwood electrical conductivity correspond to changes in sapwood moisture. Wavelet analyses indicated that lag times between inverted electrical conductivity and sapflow increased after storm events, suggesting that as soils wetted, reliance on internal water storage decreased, as did the time required to refill daily deficits in internal water storage. We found short time lags between sapflow and inverted electrical conductivity with dry conditions, when ponderosa pine are known to reduce stomatal conductance to avoid xylem cavitation. A decrease in diel amplitudes of inverted sapwood electrical conductivity during dry periods suggest that the ponderosa pine relied on internal water storage to supplement transpiration demands, but as drought conditions progressed, tree water storage contributions to transpiration decreased. Time-lapse ERI- and wavelet-analysis results highlight the important role internal tree water storage plays in supporting transpiration throughout a day and during periods of declining subsurface moisture. 

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