Water balance complexities in ephemeral catchments with different land uses: Insights from monitoring and distributed hydrologic modeling

Although ephemeral catchments are widespread in arid and semiarid climates, the relationship of their water balance with climate, geology, topography, and land cover is poorly known. Here we use 4 years (2011–2014) of rainfall, streamflow, and groundwater level measurements to estimate the water balance components in two adjacent ephemeral catchments in south-eastern Australia, with one catchment planted with young eucalypts and the other dedicated to grazing pasture. To corroborate the interpretation of the observations, the physically based hydrological model CATHY was calibrated and validated against the data in the two catchments. The estimated water balances showed that despite a significant decline in groundwater level and greater evapotranspiration in the eucalypt catchment (104–119% of rainfall) compared with the pasture catchment (95–104% of rainfall), streamflow consistently accounted for 1–4% of rainfall in both catchments for the entire study period. Streamflow in the two catchments was mostly driven by the rainfall regime, particularly rainfall frequency (i.e., the number of rain days per year), while the downslope orientation of the plantation furrows also promoted runoff. With minimum calibration, the model was able to adequately reproduce the periods of flow in both catchments in all years. Although streamflow and groundwater levels were better reproduced in the pasture than in the plantation, model-computed water balance terms confirmed the estimates from the observations in both catchments. Overall, the interplay of climate, topography, and geology seems to overshadow the effect of land use in the study catchments, indicating that the management of ephemeral catchments remains highly challenging

The striatal dopamine transporter in first-episode, drug-naive schizophrenic patients: evaluation by the new SPECT-ligand[99mTc]TRODAT-1

Following the current hypothesis that acute schizophrenic psychotic illness is associated with a triatal ‘hyperdopaminergic state’, presynaptic integrity and dopamine transporter (DAT) density in first-episode, neuroleptic-naive schizophrenic patients was measured by single-photonemission- tomography (SPECT) and compared with that in healthy control subjects. A new SPECT-ligand for assessment of the striatal DAT, the Technetium-99m-labelled tropane TRODAT-1 ([99mTc]TRODAT-1), was used. Ten inpatients suffering from a first acute schizophrenic episode and 10 age- and sex-matched healthy control subjects underwent SPECT with [99mTc]TRODAT-1. On the day of SPECT, psychopathological ratings were performed with the Brief Psychiatric Rating Scale (BPRS), the Positive and Negative Syndrome Scale (PANSS) and Schedule for Assessment of Negative Symptoms (SANS). Patients had not previously received any neuroleptic or antidepressant medication. Mean specific TRODAT-1 binding in the striatum did not differ significantly between the patient and the age- and sex-matched control group (1.25 vs. 1.28). Variance was significantly higher in the patient group. The data obtained with the new ligand in first-episode, drug-naive schizophrenic patients are in line with the PET results from the group of Laakso et al. in a comparable patient sample. [99mTc]TRODAT-1 seems to be a valuable new SPECTligand in the evaluation of the presynaptic site of the striatal dopaminergic synapse in schizophrenia

Use of laser-scan technology to analyse topography and flow in a weir pool

The development of laser-scan techniques provides opportunity for detailed terrain analysis in hydrologic studies. Ground based scans were used to model the ground surface elevation in the area of a stream gauge weir over an area of 240 m<sup>2</sup> at a resolution of 0.05 m. The terrain model was used to assess the possibility of flow bypassing the weir and to calculate stream flow during filling of the weir pool, prior to flow through the weir notch. The mapped surface shows a subtle low-lying area at the south end of the structure where flow could bypass the weir. The flow calculations quantify low-flows that do not reach the weir notch during small rain events and flow at the beginning of larger events in the ephemeral stream

Forest Biomass Observation: Current State and Prospective

With this article, we provide an overview of the methods, instruments and initiatives for forest biomass observation at a global scale. We focus on the freely available information provided by both remote and in-situ observations. The advantages and limitation of various space borne methods, including optical, radar (C, L and P band) and LiDAR, as well as respective instruments available on the orbit (MODIS, Proba-V, Landsat, Sentinel-1, Sentinel-2 , ALOS PALSAR, Envisat ASAR) or expecting (BIOMASS, GEDI, NISAR, SAOCOM-CS) are discussed. We emphasize the role of in-situ methods in the development of a biomass models, providing calibration and validation of remote sensing data. We focus on freely available forest biomass maps, databases and empirical models. We describe the functionality of Biomass.Geo-Wiki.org portal, which provides access to a collection of global and regional biomass maps in full resolution with unified legend and units overplayed with high-resolution imagery. The Forest-Observation-System.net is announced as an international cooperation to establish a global in-situ forest biomass database to support earth observation and to encourage investment in relevant field-based observations and science. Prospects of unmanned aerial vehicles in the forest inventory are briefly discussed. The work was partly supported by ESA IFBN project (contract 4000114425/15/NL/FF/gp)

Evaluation of Elevated Tritium Levels in Groundwater Downgradient from the 618-11 Burial Ground Phase I Investigations

This report describes the results of the preliminary investigation of elevated tritium in groundwater discovered near the 618-11 burial ground, located in the eastern part of the Hanford Site. Tritium in one well downgradient of the burial ground was detected at levels up to 8,140,000 pCi/L. The 618-11 burial ground received a variety of radioactive waste from the 300 Area between 1962 and 1967. The burial ground covers 3.5 hectare (8.6 acre) and contains trenches, large diameter caissons, and vertical pipe storage units. The burial ground was stabilized with a native sediment covering. The Energy Northwest reactor complex was constructed immediately east of the burial ground

Effect of Eucalyptus plantations, geology, and precipitation variability on water resources in upland intermittent catchments

Land-use change and climate variability have the potential to alter river flow and groundwater resources dramatically, especially by modifying actual evapotranspiration. Seven catchments with intermittent flow dominated by either winter-active perennial pastures (4 catchments) or Eucalyptus globulus plantations (3 catchments), located in 3 geologic settings of southeastern Australia, were studied for over 6 years to determine the primary controls on water resources. Groundwater levels in the pasture sites were stable through the 2011–2016 study period, while levels in the plantations declined in the same period. Streamflow occurred mainly during winter. Annual streamflow showed no difference clearly attributable to pasture versus plantation land use. The presence of grass buffers along streams enhances groundwater recharge and saturation-dependent overland flow, reducing the impacts of the plantations on streamflow. Site water balances indicated that the average annual actual evapotranspiration was 87–93% of precipitation for pasture catchments and 102–108% of precipitation for plantation catchments. Actual evapotranspiration greater than precipitation at the plantations was attributed to uptake of groundwater by the root system in parts of the catchments. Thus, change to groundwater storage is a critical component in the water balance. Actual evapotranspiration from pasture catchments was higher than previously estimated from global pasture and cropping data, instead matching global precipitation versus actual evapotranspiration curves for treed catchments

LACO-Wiki Mobile: An Open Source Application for In situ DataCollection and Land Cover Validation

LACO-Wiki Mobile is a smartphone application for in situ data collection, which is being developed as a freeand open source software project in the framework of the European Space Agency funded project CrowdVal. Themobile application works in tandem with the online land cover validation tool LACO-Wiki (https://www.laco-wiki.net), where users can generate a statistically robust sample for validation purposes. The land cover legend isread directly from the map uploaded to LACO-Wiki for generating the sample. The user must also indicate the typeof validation to be undertaken. Blind validation is where the user chooses the land cover type from a pre-definedlegend, plausibility validation is where users can see the land cover type from the map while on the ground andcan then choose to accept it as correct or not, while enhanced plausibility allows users to indicate the correct landcover type when it is incorrectly specified in the land cover map. This sample is then transferred to the mobileapplication, which directs users to specific locations on the ground to collect the validation data, i.e. operating in a‘directed’ mode. The user can see the locations of the points on the mobile phone, and as they approach a point, theuser is given the option to validate the land cover. These points can then be used in the accuracy assessment of theland cover map. The application also operates in ‘opportunistic’ mode, i.e. allowing the user to collect land coverat any location of their choice, e.g. while driving along a road. Such data collection can be useful for verifyingvisually interpreted samples or complementing training data for the development of land cover maps. Although theopen source application is still under development, a version will be openly accessible in github by the time of theconference