02567nas a2200337   4500008004100000245010300041210006900144260001200213300000900225490000700234520158600241653001601827653001201843653001401855653001901869653001801888100002401906700002201930700002401952700002001976700002101996700002102017700002502038700002102063700002102084700001902105700002102124700001702145700002102162856004602183       2023                        eng d00aThe distribution of surface soil moisture over space and time in eastern Taylor Valley, Antarctica0 adistribution of surface soil moisture over space and time in eas  c06/2023  a31700 v153 a<p>Available soil moisture is thought to be the limiting factor for most ecosystem processes in the cold polar desert of the McMurdo Dry Valleys (MDVs) of Antarctica. Previous studies have shown that microfauna throughout the MDVs are capable of biological activity when sufficient soil moisture is available (~2&ndash;10% gravimetric water content), but few studies have attempted to quantify the distribution, abundance, and frequency of soil moisture on scales beyond that of traditional field work or local field investigations. In this study, we present our work to quantify the soil moisture content of soils throughout the Fryxell basin using multispectral satellite remote sensing techniques. Our efforts demonstrate that ecologically relevant abundances of liquid water are common across the landscape throughout the austral summer. On average, the Fryxell basin of Taylor Valley is modeled as containing 1.5 &plusmn; 0.5% gravimetric water content (GWC) across its non-fluvial landscape with ~23% of the landscape experiencing an average GWC &gt; 2% throughout the study period, which is the observed limit of soil nematode activity. These results indicate that liquid water in the soils of the MDVs may be more abundant than previously thought, and that the distribution and availability of liquid water is dependent on both soil properties and the distribution of water sources. These results can also help to identify ecological hotspots in the harsh polar Antarctic environment and serve as a baseline for detecting future changes in the soil hydrological regime.</p>10aDry valleys10aecology10ahydrology10aremote sensing10asoil moisture1 aSalvatore, Mark, R.1 aBarrett, John, E.1 aFackrell, Laura, E.1 aSokol, Eric, R.1 aLevy, Joseph, S.1 aKuentz, Lily, C.1 aGooseff, Michael, N.1 aAdams, Byron, J.1 aPower, Sarah, N.1 aKnightly, Paul1 aMatul, Haley, M.1 aSzutu, Brian1 aDoran, Peter, T.  uhttps://www.mdpi.com/2072-4292/15/12/317002175nas a2200229   4500008004100000022001400041245022200055210006900277260001200346300001400358490000700372520135100379653001501730653001601745653001901761653001601780653001201796100002101808700002101829700002401850856007101874       2022                        eng d  a1523-043000aTiming and duration of ephemeral Antarctic water tracks and wetlands using high temporal–resolution satellite imagery, high spatial–resolution satellite imagery, and ground-based sensors in the McMurdo Dry Valleys0 aTiming and duration of ephemeral Antarctic water tracks and wetl  c12/2022  a538 - 5610 v543 a<p>Antarctic water tracks and ephemeral wetlands are a primary location for biogeochemical soil processes driving cold desert soil formation. Though the spatial extent of water tracks and wetted soils has been mapped in the McMurdo Dry Valleys (MDV) on the basis of mapping darkened pixels in high-resolution commercial satellite imagery, the timescale over which water tracks and wetlands form and the duration of these biogeochemically active environments remain unknown. Here, we determine the start date and end dates and the duration of wetted soils at ten sites located across the MDV using a combination of in situ soil sensors and two complementary remote imaging platforms (Planet and WorldView) to understand the hydroclimatic processes that drive water track and wetland formation. Our remote sensing employs a terrain correction workflow that removes the contribution of differential direct illumination and small-scale shadowing on pixel brightness, reducing false positives (soils identified as wetted when in fact they are shadowed or darkened as a consequence of high phase angle). Our findings extend the water track and wetland hydroperiod by over a month, showing darkening occurring from November to March, suggesting hydrological contributions from ground ice thaw, snowmelt, and salt deliquescence and soil brine growth.</p>10aAntarctica10ahydroperiod10aremote sensing10awater track10awetland1 aKuentz, Lily, C.1 aLevy, Joseph, S.1 aSalvatore, Mark, R.  uhttps://www.tandfonline.com/doi/full/10.1080/15230430.2022.2123858