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The Western Boreal Plain of north‐central Alberta is prone to water‐deficit conditions and is hydrologically sensitive to changes in climate, natural resource extraction and disturbance. Accurate measurement and modelling of the main components of the water balance are important for ecosystem and reclamation management; however, the lack of hydro‐meteorological instrumentation found within different land cover types makes quantification of changes to the water balance difficult over large areas. Remote sensing data can provide spatial estimates of land cover distribution and leaf area index (LAI) used as inputs into land surface models. However, land surface models can often suffer from inaccuracies as a result of spatial (coarse pixel) and temporal (discrete acquisition) resolutions, mis‐classification and inaccurate representation of LAI using remote sensing data. This study uses high‐resolution (1 m × 1 m) Light Detection and Ranging‐derived vegetation parameters (land cover type, LAI and 3D vegetation frictional influences on air movement) as inputs into the Penman–Monteith evapotranspiration (ET) model along with measured hydro‐meteorological variables. Comparison with eddy covariance (EC) measurements indicated that spatially explicit ET estimates at 1 m resolution (over a 5 km × 5 km study area) provided better estimates compared with bulk average ET estimates per land cover type. ET estimates scaled using spatially variable vegetation inputs only underestimated measured fluxes by 2% and 3% at 22·5 and 3 m EC instrumentation towers, respectively. Bulk averaged ET estimates underestimated measured ET by 5% at the 3 m tower and overestimated EC by 7% at the 22·5 m EC tower. Over coarser scales, the error associated with bulk input parameters can lead to error in overall water balance estimation. Copyright © 2014 John Wiley & Sons, Ltd.

We developed a method to measure hemoglobin synthesis rate (SynHb) in humans, assuming that free glycine in the red blood cell (RBC) represents free glycine in bone marrow for hemoglobin synthesis. The present rat study examines this assumption of the method and quantifies SynHb in rats. Sprague-Dawley rats (n = 9) were studied, [2-13 C]glycine was intravenously infused over 24 h (2.5 mg kg −1 h −1 ), blood was drawn for glycine and heme isolation, and bone marrow was harvested for glycine isolation. Isotopic enrichments of glycine and heme were measured, fractional hemoglobin synthesis rate (fSynHb% day −1 ) was calculated, and from this a value for SynHb (mg g −1 day −1 ) was derived. Mean body weight was 446 ± 10 g (mean ± SE) and hemoglobin concentration was 14 ± 0.5 g dl −1 . At 24 h, the mean isotopic enrichment, atom percentage excess (APE), of the RBC free glycine (1.56 ± 0.18 APE) was similar to the bone marrow (1.68 ± 0.15 APE). The rate of incorporation of 13 C into heme increased over time from 0.0004 APE/h between 6 and 12 h, to 0.0014 APE/h between 12 and 18 h, and 0.0024 APE/h between 18 and 24 h. Consequently, fSynHb (1.19 ± 0.32, 2.92 ± 0.66, and 4.22 ± 0.56% day −1 , respectively) and SynHb (0.11 ± 0.03, 0.28 ± 0.05, and 0.42 ± 0.05 mg g −1 day −1 , respectively) showed similar patterns over the 24-h study period. We conclude that (1) enrichment of free glycine in the circulating RBC approximates enrichment of bone marrow free glycine for heme formation and (2) this pattern of hemoglobin synthesis rate is reflecting the characteristic release and gradual maturation of reticulocytes in the circulation. Keywords hemoglobin synthesis; anemia; glycine; bone marrow; rats Hemoglobin metabolism is likely to be adversely affected in nutritional anemias and blood diseases of genetic or nongenetic origin. Many attempts have been made to obtain basic information about blood diseases by estimating the life span of the red blood cell (RBC

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Over the last several decades the hydrologically sensitive Boreal Plains ecoregion of Western Canada has experienced significant warming and drying. To better predict implications of land cover changes on evapotranspiration (ET) and future water resources in this region we used high resolution light detection and ranging and energy balance data to spatially parameterise the Penman-Monteith ET model. Within a 5 km x 5 km area of peatland ecosystems, riparian boundaries, and upland mixedwood forests, the influence of land cover heterogeneity on the accuracy of modelled ET is examined at pixel sizes of 1, 10, 25, 250, 500 and 1000 m, representing resolutions common to popular satellite products (SPOT, Landsat and MODIS). Modelled ET was compared with tower-based eddy covariance measurements using a weighted flux footprint model. Errors range from 10% to 36% of measured fluxes and results indicate that sensors with small pixel sizes (1 m) offer significantly better accuracy in large heterogeneous flux footprints, while a wider range of pixel sizes (<25 m) can be suitably applied to smaller homogeneous footprints. Mid (250 m) and coarse (>500 m) pixel sizes offered significantly less accuracy, although changes in pixel size within this range offered comparable results.