EVALUATING WATER USE STRATEGIES IN OLIVE TREES GROWN UNDER DIFFERENT WATER AVAILABILITY REGIMES THROUGH AN INTEGRATED APPROACH OF SAP FLOW AND HIGH RESOLUTION STEM GROWTH ANALYSIS

2009 ◽  
pp. 151-158
Author(s):  
A. Giovannelli ◽  
M.L. Traversi ◽  
L. Sebastiani ◽  
R. Tognetti ◽  
R. d'Andria ◽  
...  
Keyword(s):  
High Resolution ◽  
Water Use ◽  
Water Availability ◽  
Sap Flow ◽  
Growth Analysis ◽  
Integrated Approach ◽  
Stem Growth ◽  
Olive Trees

THE IMPORTANCE OF SAP FLOW MEASUREMENTS TO ESTIMATE ACTUAL WATER USE OF MESKI OLIVE TREES UNDER DIFFERENT IRRIGATION REGIMES IN TUNISIA

2012 ◽  
Vol 61 (5) ◽  
pp. 645-656 ◽  
Author(s):  
Maurits W. Vandegehuchte ◽  
Mohamed Braham ◽  
Raoul Lemeur ◽  
Kathy Steppe
Keyword(s):  
Water Use ◽  
Sap Flow ◽  
Flow Measurements ◽  
Irrigation Regimes ◽  
Olive Trees ◽  
Sap Flow Measurements

scholarly journals Effect of Long-Term vs. Short-Term Ambient Ozone Exposure on Radial Stem Growth, Sap Flux and Xylem Morphology of O3-Sensitive Poplar Trees

Forests ◽  
2019 ◽  
Vol 10 (5) ◽  
pp. 396 ◽  
Author(s):  
Alessio Giovannelli ◽  
Maria Laura Traversi ◽  
Monica Anichini ◽  
Yasutomo Hoshika ◽  
Silvano Fares ◽  
...  
Keyword(s):  
Water Use ◽  
Sap Flow ◽  
Stem Growth ◽  
Ozone Exposure ◽  
Compensatory Mechanisms ◽  
Planted Forests ◽  
Evaporative Demand ◽  
Huber Value ◽  
Stem Water

High ozone (O3) pollution impairs the carbon and water balance of trees, which is of special interest in planted forests. However, the effect of long-term O3 exposure on tree growth and water use, little remains known. In this study, we analysed the relationships of intra-annual stem growth pattern, seasonal sap flow dynamics and xylem morphology to assess the effect of long term O3 exposure of mature O3-sensitive hybrid poplars (‘Oxford’ clone). Rooted cuttings were planted in autumn 2007 and drip irrigated with 2 liters of water as ambient O3 treatment, or 450 ppm ethylenediurea (N-[2-(2-oxo-1-imidazolidinyl)ethyl]-N0-phenylurea, abbreviated as EDU) solution as O3 protection treatment over all growing seasons. During 2013, point dendrometers and heat pulses were installed to monitor radial growth, stem water relations and sap flow. Ambient O3 did not affect growth rates, even if the seasonal culmination point was 20 days earlier on average than that recorded in the O3 protected trees. Under ambient O3, trees showed reduced seasonal sap flow, however, the lower water use was due to a decrease of Huber value (decrease of leaf area for sapwood unit) rather than to a change in xylem morphology or due to a direct effect of sluggish stomatal responses on transpiration. Under high evaporative demand and ambient O3 concentrations, trees showed a high use of internal stem water resources modulated by stomatal sluggishness, thus predisposing them to be more sensitive water deficit during summer. The results of this study help untangle the compensatory mechanisms involved in the acclimation processes of forest species to long-term O3 exposure in a context of global change.

scholarly journals Environmental Drivers of Water Use for Caatinga Woody Plant Species: Combining Remote Sensing Phenology and Sap Flow Measurements

2020 ◽  
Vol 13 (1) ◽  
pp. 75
Author(s):  
Rennan A. Paloschi ◽  
Desirée Marques Ramos ◽  
Dione J. Ventura ◽  
Rodolfo Souza ◽  
Eduardo Souza ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Soil Moisture ◽  
Soil Water ◽  
Plant Species ◽  
Water Use ◽  
Water Availability ◽  
Sap Flow ◽  
Vegetation Index ◽  
Environmental Drivers ◽  
Near Surface

We investigated the water use of Caatinga vegetation, the largest seasonally dry forest in South America. We identified and analysed the environmental phenological drivers in woody species and their relationship with transpiration. To monitor the phenological evolution, we used remote sensing indices at different spatial and temporal scales: normalized difference vegetation index (NDVI), soil adjusted vegetation index (SAVI), and green chromatic coordinate (GCC). To represent the phenology, we used the GCC extracted from in-situ automated digital camera images; indices calculated based on sensors included NDVI, SAVI and GCC from Sentinel-2A and B satellites images, and NDVI products MYD13Q1 and MOD13Q1 from a moderate-resolution imaging spectroradiometer (MODIS). Environmental drivers included continuously monitored rainfall, air temperature, soil moisture, net radiation, and vapour pressure deficit. To monitor soil water status and vegetation water use, we installed soil moisture sensors along three soil profiles and sap flow sensors for five plant species. Our study demonstrated that the near-surface GCC data played an important role in permitting individual monitoring of species, whereas the species’ sap flow data correlated better with NDVI, SAVI, and GCC than with species’ near-surface GCC. The wood density appeared to affect the transpiration cessation times in the dry season, given that species with the lowest wood density reach negligible values of transpiration earlier in the season than those with high woody density. Our results show that soil water availability was the main limiting factor for transpiration during more than 80% of the year, and that both the phenological response and water use are directly related to water availability when relative saturation of the soil profile fell below 0.25.

Water Availability--The Connection Between Water Use and Quality

Fact Sheet ◽  
2008 ◽  
Author(s):  
Robert M. Hirsch ◽  
Pixie A. Hamilton ◽  
Timothy L. Miller ◽  
Donna N. Myers
Keyword(s):  
Water Use ◽  
Water Availability

High-Resolution Climate Change Impact Analysis on Expected Future Water Availability in the Upper Jordan Catchment and the Middle East

2014 ◽  
Vol 15 (4) ◽  
pp. 1517-1531 ◽  
Author(s):  
Gerhard Smiatek ◽  
Harald Kunstmann ◽  
Andreas Heckl
Keyword(s):  
Climate Change ◽  
High Resolution ◽  
Water Availability ◽  
Impact Analysis ◽  
River Flow ◽  
Climate Model ◽  
Mesoscale Model ◽  
Global Climate Model ◽  
Full Range ◽  
The Impact

Abstract The impact of climate change on the future water availability of the upper Jordan River (UJR) and its tributaries Dan, Snir, and Hermon located in the eastern Mediterranean is evaluated by a highly resolved distributed approach with the fifth-generation Pennsylvania State University–NCAR Mesoscale Model (MM5) run at 18.6- and 6.2-km resolution offline coupled with the Water Flow and Balance Simulation Model (WaSiM). The MM5 was driven with NCEP reanalysis for 1971–2000 and with Hadley Centre Coupled Model, version 3 (HadCM3), GCM forcings for 1971–2099. Because only one regional–global climate model combination was applied, the results may not give the full range of possible future projections. To describe the Dan spring behavior, the hydrological model was extended by a bypass approach to allow the fast discharge components of the Snir to enter the Dan catchment. Simulation results for the period 1976–2000 reveal that the coupled system was able to reproduce the observed discharge rates in the partially karstic complex terrain to a reasonable extent with the high-resolution 6.2-km meteorological input only. The performed future climate simulations show steadily rising temperatures with 2.2 K above the 1976–2000 mean for the period 2031–60 and 3.5 K for the period 2070–99. Precipitation trends are insignificant until the middle of the century, although a decrease of approximately 12% is simulated. For the end of the century, a reduction in rainfall ranging between 10% and 35% can be expected. Discharge in the UJR is simulated to decrease by 12% until 2060 and by 26% until 2099, both related to the 1976–2000 mean. The discharge decrease is associated with a lower number of high river flow years.

scholarly journals High-Resolution Spatiotemporal Water Use Mapping of Surface and Direct-Root-Zone Drip-Irrigated Grapevines Using UAS-Based Thermal and Multispectral Remote Sensing

2021 ◽  
Vol 13 (5) ◽  
pp. 954
Author(s):  
Abhilash K. Chandel ◽  
Lav R. Khot ◽  
Behnaz Molaei ◽  
R. Troy Peters ◽  
Claudio O. Stöckle ◽  
...  
Keyword(s):  
High Resolution ◽  
Water Use ◽  
Root Zone ◽  
Lateral Roots ◽  
Irrigation Treatment ◽  
Crop Coefficient ◽  
Spatiotemporal Resolution ◽  
Site Specific ◽  
Canopy Transpiration ◽  
Irrigation Treatments

Site-specific irrigation management for perennial crops such as grape requires water use assessments at high spatiotemporal resolution. In this study, small unmanned-aerial-system (UAS)-based imaging was used with a modified mapping evapotranspiration at high resolution with internalized calibration (METRIC) energy balance model to map water use (UASM-ET approach) of a commercial, surface, and direct-root-zone (DRZ) drip-irrigated vineyard. Four irrigation treatments, 100%, 80%, 60%, and 40%, of commercial rate (CR) were also applied, with the CR estimated using soil moisture data and a non-stressed average crop coefficient of 0.5. Fourteen campaigns were conducted in the 2018 and 2019 seasons to collect multispectral (ground sampling distance (GSD): 7 cm/pixel) and thermal imaging (GSD: 13 cm/pixel) data. Six of those campaigns were near Landsat 7/8 satellite overpass of the field site. Weather inputs were obtained from a nearby WSU-AgWeatherNet station (1 km). First, UASM-ET estimates were compared to those derived from soil water balance (SWB) and conventional Landsat-METRIC (LM) approaches. Overall, UASM-ET (2.70 ± 1.03 mm day−1 [mean ± std. dev.]) was higher than SWB-ET (1.80 ± 0.98 mm day−1). However, both estimates had a significant linear correlation (r = 0.64–0.81, p < 0.01). For the days of satellite overpass, UASM-ET was statistically similar to LM-ET, with mean absolute normalized ET departures (ETd,MAN) of 4.30% and a mean r of 0.83 (p < 0.01). The study also extracted spatial canopy transpiration (UASM-T) maps by segmenting the soil background from the UASM-ET, which had strong correlation with the estimates derived by the standard basal crop coefficient approach (Td,MAN = 14%, r = 0.95, p < 0.01). The UASM-T maps were then used to quantify water use differences in the DRZ-irrigated grapevines. Canopy transpiration (T) was statistically significant among the irrigation treatments and was highest for grapevines irrigated at 100% or 80% of the CR, followed by 60% and 40% of the CR (p < 0.01). Reference T fraction (TrF) curves established from the UASM-T maps showed a notable effect of irrigation treatment rates. The total water use of grapevines estimated using interpolated TrF curves was highest for treatments of 100% (425 and 320 mm for the 2018 and 2019 seasons, respectively), followed by 80% (420 and 317 mm), 60% (391 and 318 mm), and 40% (370 and 304 mm) of the CR. Such estimates were within 5% to 11% of the SWB-based water use calculations. The UASM-T-estimated water use was not the same as the actual amount of water applied in the two seasons, probably because DRZ-irrigated vines might have developed deeper or lateral roots to fulfill water requirements outside the irrigated soil volume. Overall, results highlight the usefulness of high-resolution imagery toward site-specific water use management of grapevines.

scholarly journals How downstream sub-basins depend on upstream inflows to avoid scarcity: typology and global analysis of transboundary rivers

2018 ◽  
Vol 22 (5) ◽  
pp. 2795-2809 ◽  
Author(s):  
Hafsa Ahmed Munia ◽  
Joseph H. A. Guillaume ◽  
Naho Mirumachi ◽  
Yoshihide Wada ◽  
Matti Kummu
Keyword(s):  
Water Stress ◽  
Water Use ◽  
Water Availability ◽  
Water Scarcity ◽  
Management Practices ◽  
Global Analysis ◽  
Water Shortage ◽  
River Basins ◽  
Analytical Framework ◽  
Available Water

Abstract. Countries sharing river basins are often dependent upon water originating outside their boundaries; meaning that without that upstream water, water scarcity may occur with flow-on implications for water use and management. We develop a formalisation of this concept drawing on ideas about the transition between regimes from resilience literature, using water stress and water shortage as indicators of water scarcity. In our analytical framework, dependency occurs if water from upstream is needed to avoid scarcity. This can be diagnosed by comparing different types of water availability on which a sub-basin relies, in particular local runoff and upstream inflows. At the same time, possible upstream water withdrawals reduce available water downstream, influencing the latter water availability. By developing a framework of scarcity and dependency, we contribute to the understanding of transitions between system regimes. We apply our analytical framework to global transboundary river basins at the scale of sub-basin areas (SBAs). Our results show that 1175 million people live under water stress (42 % of the total transboundary population). Surprisingly, the majority (1150 million) of these currently suffer from stress only due to their own excessive water use and possible water from upstream does not have impact on the stress status – i.e. they are not yet dependent on upstream water to avoid stress – but could still impact on the intensity of the stress. At the same time, 386 million people (14 %) live in SBAs that can avoid stress owing to available water from upstream and have thus upstream dependency. In the case of water shortage, 306 million people (11 %) live in SBAs dependent on upstream water to avoid possible shortage. The identification of transitions between system regimes sheds light on how SBAs may be affected in the future, potentially contributing to further refined analysis of inter- and intrabasin hydro-political power relations and strategic planning of management practices in transboundary basins.

scholarly journals Modelling global water stress of the recent past: on the relative importance of trends in water demand and climate variability

2011 ◽  
Vol 15 (12) ◽  
pp. 3785-3808 ◽  
Author(s):  
Y. Wada ◽  
L. P. H. van Beek ◽  
M. F. P. Bierkens
Keyword(s):  
Water Stress ◽  
Climate Variability ◽  
Water Use ◽  
Extreme Events ◽  
Water Availability ◽  
Water Scarcity ◽  
Water Demand ◽  
Developing Economies ◽  
Blue Water ◽  
Global Population

Abstract. During the past decades, human water use has more than doubled, yet available freshwater resources are finite. As a result, water scarcity has been prevalent in various regions of the world. Here, we present the first global assessment of past development of water stress considering not only climate variability but also growing water demand, desalinated water use and non-renewable groundwater abstraction over the period 1960–2001 at a spatial resolution of 0.5°. Agricultural water demand is estimated based on past extents of irrigated areas and livestock densities. We approximate past economic development based on GDP, energy and household consumption and electricity production, which are subsequently used together with population numbers to estimate industrial and domestic water demand. Climate variability is expressed by simulated blue water availability defined by freshwater in rivers, lakes, wetlands and reservoirs by means of the global hydrological model PCR-GLOBWB. We thus define blue water stress by comparing blue water availability with corresponding net total blue water demand by means of the commonly used, Water Scarcity Index. The results show a drastic increase in the global population living under water-stressed conditions (i.e. moderate to high water stress) due to growing water demand, primarily for irrigation, which has more than doubled from 1708/818 to 3708/1832 km3 yr−1 (gross/net) over the period 1960–2000. We estimate that 800 million people or 27% of the global population were living under water-stressed conditions for 1960. This number is eventually increased to 2.6 billion or 43% for 2000. Our results indicate that increased water demand is a decisive factor for heightened water stress in various regions such as India and North China, enhancing the intensity of water stress up to 200%, while climate variability is often a main determinant of extreme events. However, our results also suggest that in several emerging and developing economies (e.g. India, Turkey, Romania and Cuba) some of past extreme events were anthropogenically driven due to increased water demand rather than being climate-induced.

Sign in / Sign up

Export Citation Format

Share Document