scholarly journals Partitioning of evaporation into transpiration, soil evaporation and interception: a comparison between isotope measurements and a HYDRUS-1D model

2012 ◽  
Vol 16 (8) ◽  
pp. 2605-2616 ◽  
Author(s):  
S. J. Sutanto ◽  
J. Wenninger ◽  
A. M. J. Coenders-Gerrits ◽  
S. Uhlenbrook
Keyword(s):  
Mass Balance ◽  
Temporal Resolution ◽  
Soil Evaporation ◽  
High Temporal Resolution ◽  
Total Evaporation ◽  
Resolution Analysis ◽  
1D Model ◽  
Isotope Mass Balance ◽  
Hydrus 1D ◽  
Isotope Measurements

Abstract. Knowledge of the water fluxes within the soil-vegetation-atmosphere system is crucial to improve water use efficiency in irrigated land. Many studies have tried to quantify these fluxes, but they encountered difficulties in quantifying the relative contribution of evaporation and transpiration. In this study, we compared three different methods to estimate evaporation fluxes during simulated summer conditions in a grass-covered lysimeter in the laboratory. Only two of these methods can be used to partition total evaporation into transpiration, soil evaporation and interception. A water balance calculation (whereby rainfall, soil moisture and percolation were measured) was used for comparison as a benchmark. A HYDRUS-1D model and isotope measurements were used for the partitioning of total evaporation. The isotope mass balance method partitions total evaporation of 3.4 mm d−1 into 0.4 mm d−1 for soil evaporation, 0.3 mm d−1 for interception and 2.6 mm d−1 for transpiration, while the HYDRUS-1D partitions total evaporation of 3.7 mm d−1 into 1 mm d−1 for soil evaporation, 0.3 mm d−1 for interception and 2.3 mm d−1 for transpiration. From the comparison, we concluded that the isotope mass balance is better for low temporal resolution analysis than the HYDRUS-1D. On the other hand, HYDRUS-1D is better for high temporal resolution analysis than the isotope mass balance.

scholarly journals Partitioning of evaporation into transpiration, soil evaporation and interception: a combination of hydrometric measurements and stable isotope analyses

2012 ◽  
Vol 9 (3) ◽  
pp. 3657-3690 ◽  
Author(s):  
S. J. Sutanto ◽  
J. Wenninger ◽  
A. M. J. Coenders-Gerrits ◽  
S. Uhlenbrook
Keyword(s):  
Water Balance ◽  
Best Practice ◽  
Soil Evaporation ◽  
Total Evaporation ◽  
Relative Contribution ◽  
Security Problem ◽  
1D Model ◽  
Use Efficiency ◽  
Monteith Equation ◽  
Hydrus 1D

Abstract. Best practice agriculture is the key to overcome the food security problem through improvement of water use efficiency. Therefore, knowledge of the water fluxes within the soil-vegetation-atmosphere system is crucial. Many studies have tried to quantify these fluxes, but they encountered difficulties in quantifying the relative contribution of evaporation and transpiration. In this study, we compared four different methods to estimate evaporation fluxes during simulated summer conditions in a grassland lysimeter in the UNESCO-IHE laboratory. Only two of these methods can be used to partition total evaporation into transpiration, soil evaporation and interception. A water balance calculation (whereby rainfall, soil moisture and percolation was measured) and the Penman-Monteith equation were applied to determine total evaporation. A HYDRUS-1D model and isotope measurements were used for the partitioning of total evaporation. The average total evaporation was 3.2 mm d−1 calculated with the water balance, 3.4 mm d−1 for the Penman-Monteith equation, 3.4 mm d−1 calculated with HYDRUS-1D, and 3.1 mm d−1 with the isotope mass balance. By use of the isotopes, we separated the total evaporation on average into 2.4 mm d−1 transpiration (77.7%), 0.4 mm d−1 soil evaporation (12.2%), and 0.3 mm d−1 interception (10.1%).

scholarly journals Revealing the time course of laser evoked potential habituation by high temporal resolution analysis

2021 ◽  
Author(s):  
D. Kersebaum ◽  
S.‐C. Fabig ◽  
M. Sendel ◽  
A. C. Muntean ◽  
R. Baron ◽  
...  
Keyword(s):  
Temporal Resolution ◽  
Time Course ◽  
Evoked Potential ◽  
High Temporal Resolution ◽  
Resolution Analysis

High-temporal-resolution analysis demonstrates that ICAM-1 stabilizes WEHI 274.1 monocytic cell rolling on endothelium

2003 ◽  
Vol 285 (1) ◽  
pp. C112-C118 ◽  
Author(s):  
Christopher G. Kevil ◽  
John H. Chidlow ◽  
Daniel C. Bullard ◽  
Dennis F. Kucik
Keyword(s):  
Temporal Resolution ◽  
High Temporal Resolution ◽  
Leukocyte Rolling ◽  
Wild Type ◽  
Monocytic Cell ◽  
Monocytic Cell Line ◽  
Rolling Velocity ◽  
Tnf Α ◽  
Resolution Analysis ◽  
Adhesive Interactions

Leukocyte rolling, adhesion, and migration on vascular endothelium involve several sets of adhesion molecules that interact simultaneously. Each of these receptor-ligand pairs may play multiple roles. We examined the role of ICAM-1 in adhesive interactions with mouse aortic endothelial cells (MAECs) in an in vitro flow system. Average rolling velocity of the monocytic cell line WEHI 274.1 was increased on ICAM-1-deficient MAECs compared with wild-type MAECs, both with and without TNF-α stimulation. High-temporal-resolution analysis provided insights into the underlying basis for these differences. Without TNF-α stimulation, average rolling velocity was slower on wild-type than on ICAM-1-deficient endothelium because of brief (<1 s) pauses. On TNF-α-stimulated ICAM-1-deficient endothelium, cells rolled faster because of transient accelerations, producing “jerky” rolling. Firm adhesion to ICAM-1-deficient MAECs was significantly reduced compared with wild-type MAECs, although the number of rolling cells was similar. These results demonstrate directly that ICAM-1 affects rolling velocity by stabilizing leukocyte rolling.

Isotope labeling experiment to infer ecohydrological travel times

2020 ◽  
Author(s):  
David Mennekes ◽  
Michael Rinderer ◽  
Stefan Seeger ◽  
Hugo de Boer ◽  
Natalie Orlowski ◽  
...  
Keyword(s):  
Soil Water ◽  
Water Uptake ◽  
Temporal Resolution ◽  
Water Vapor Pressure ◽  
Root Water Uptake ◽  
Field Conditions ◽  
High Temporal Resolution ◽  
Travel Times ◽  
Isotope Measurements

&lt;p&gt;Stable water isotopes are promising tracers to study soil-tree interactions and root water uptake. Traditionally, destructive sampling techniques are applied to measure the isotopic signature in soils and plant tissues but these methods are limited in their temporal resolution. For calculating ecohydrological travel times from soil water to transpiration, high frequent isotope measurements are required. Recently, in-situ water isotope probes have been successfully applied in beech trees to yield high-frequent isotope measurements under field conditions but the complexity and heterogeneity of natural field conditions can make a systematical method testing difficult. Here, we test whether the new probes are capable of capturing tree species-specific differences in root water uptake and associated travel times.&lt;br&gt;We test this in a controlled experiment using large pots with three 4-6 meter high and 20 year old coniferous and deciduous trees: &lt;em&gt;Pinus pinea&lt;/em&gt;, &lt;em&gt;Alnus&lt;/em&gt; &lt;em&gt;x spaethii&lt;/em&gt; and &lt;em&gt;Quercus&lt;/em&gt; &lt;em&gt;suber&lt;/em&gt; that are expected to have different water uptake strategies. We applied deuterated irrigation water to the homogeneous soils in the pots and traced the water flux from the soils through the trees with in-situ isotope probes in high temporal resolution.&lt;br&gt;This contribution presents preliminary results on ecohydrological travel times in relation to environmental parameters such as sap flow, photosynthetic activity, matrix potential, soil water content, water vapor pressure deficit and solar radiation.&lt;br&gt;Our in-situ isotope probes were capable to capture the breakthrough of the isotope tracer in all trees. The calculated travel times were shorter for the Pinus and Alnus compared to the Quercus which suggests differences in root water uptake. Detailed results from such controlled experiments are fundamental for testing new measurement techniques such as the in-situ isotope probes. Such results are important to better interpret results measured under natural and therefore more complex and heterogeneous field conditions.&lt;/p&gt;

Multidetector-row Computed Tomography in the Assessment of Coronary Artery Disease – New Techniques and Insights

2010 ◽  
Vol 6 (2) ◽  
pp. 43 ◽  
Author(s):  
Andreas H Mahnken ◽  
Keyword(s):  
Computed Tomography ◽  
Coronary Artery Disease ◽  
Coronary Artery ◽  
Data Acquisition ◽  
Temporal Resolution ◽  
High Temporal Resolution ◽  
Multidetector Row ◽  
Ct Scanners ◽  
Artery Disease ◽  
Cardiac Mdct

Over the last decade, cardiac computed tomography (CT) technology has experienced revolutionary changes and gained broad clinical acceptance in the work-up of patients suffering from coronary artery disease (CAD). Since cardiac multidetector-row CT (MDCT) was introduced in 1998, acquisition time, number of detector rows and spatial and temporal resolution have improved tremendously. Current developments in cardiac CT are focusing on low-dose cardiac scanning at ultra-high temporal resolution. Technically, there are two major approaches to achieving these goals: rapid data acquisition using dual-source CT scanners with high temporal resolution or volumetric data acquisition with 256/320-slice CT scanners. While each approach has specific advantages and disadvantages, both technologies foster the extension of cardiac MDCT beyond morphological imaging towards the functional assessment of CAD. This article examines current trends in the development of cardiac MDCT.

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