What control the spatial patterns and predictions of runoff response over the contiguous USA?

Understanding the nonlinear relationship between hydrological response and key factors and the cause behind this relationship is vital for water resource management and earth system model.In this study,we undertook several steps to explore the relationship.Initially,we partitioned runoff response change(RRC)into multiple components associated with climate and catchment properties,and examined the spatial patterns and smoothness indicated by the Moran's Index of RRC across the contiguous United States(CONUS).Subsequently,we employed a machine learning model to predict RRC using catchment attribute predictors encompassing climate,topography,hydrology,soil,land use/cover,and geology.Additionally,we identified the primary factors influencing RRC and quantified how these key factors control RRC by employing the accumulated local effect,which allows for the representation of not only dominant but also secondary effects.Finally,we explored the relationship between ecoregion patterns,climate gradients,and the distribution of RRC across CONUS.Our findings indicate that:(1)RRC demonstrating significant connections between catchments tends to be well predicted by catchment attributes in space;(2)climate,hydrology,and topography emerge as the top three key attributes nonlinearly influencing the RRC patterns,with their second-order effects determining the heterogeneous patterns of RRC;and(3)local Moran's I signifies a collaborative relationship between the patterns of RRC and their spatial smoothness,climate space,and ecoregions.

Local temperature and El Niño Southern Oscillation influence migration phenology of East Asian migratory waterbirds wintering in Poyang,China

Temperature is a critical factor influencing avian phenology,due to its direct impact on food and water availability.Most previous studies have focused on the timing of spring migration and the arrival of birds at breeding grounds along the European and American flyways;little is known about migration ecology at the wintering sites along the Asian flyways.Using linear regression models,this study investigates how local temperature variation and EI Niño Southern Oscillation(ENSO)influences the arrival and departure timing of 9 waterbird species breeding in Mongolia or Siberia and overwintering in Poyang,China from 2002 to 2013.Birds mainly arrive at Poyang in October and depart for their breeding sites in March.Out of the 9 species,6 show a strong negative relationship between departure time and overwintering temperature in Poyang.Departure dates also show a negative association with overwintering ENSO and March ENSO for two species.Both local and large-scale climate indices show no influence on the arrival timing of waterbirds.We suggest that birds react to the annual variation of overwintering temperature:an earlier departure of waterbirds is facilitated by a warmer overwintering period and vice versa.The long-term accumulated temperature effect is more pronounced than ENSO and the short-term local temperature effect.Our findings could help quantify the potential impact of global warming on waterbirds.

Proton production,regulation and pathophysiological roles in the mammalian brain

The recent demonstration of proton signaling in C. elegans muscle contraction suggests a novel mechanism for proton-based intercellular communication and has stimulated enthusiasm for exploring proton signaling in higher organ- isms. Emerging evidence indicates that protons are produced and regulated in localized space and time. Furthermore, identification of proton regulators and sensors in the brain leads to the speculation that proton production and regulation may be of major importance for both physiological and pathological functions ranging from nociception to learning and memory. Extracellular protons may play a role in signal transmission by not only acting on adjacent ceils hut also af- fecting the cell from which they were released. In this review, we summarize the upstream and downstream pathways of proton production and regulation in the mammalian brain, with special emphasis on the proton extruders and sensors that are critical in the homeostatic regulation of pH, and discuss their potential roles in proton signaling under normal and pathophysiological conditions.