scholarly journals Erratum to “Construction of Minirhizotron Facilities for Investigating Root Zone Processes” and “Parameterization of Root Water Uptake Models Considering Dynamic Root Distributions and Water Uptake Compensation”

2018 ◽  
Vol 17 (1) ◽  
pp. 170201 ◽  
Author(s):  
Gaochao Cai ◽  
Shehan Morandage ◽  
Jan Vanderborght ◽  
Andrea Schnepf ◽  
Harry Vereecken
Keyword(s):  
Water Uptake ◽  
Root Zone ◽  
Root Water Uptake ◽  
Root Distributions

scholarly journals Modelling the Impact on Root Water Uptake and Solute Return Flow of Different Drip Irrigation Regimes with Brackish Water

Water ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 425 ◽  
Author(s):  
Fairouz Slama ◽  
Nessrine Zemni ◽  
Fethi Bouksila ◽  
Roberto De Mascellis ◽  
Rachida Bouhlila
Keyword(s):  
Water Content ◽  
Soil Water ◽  
Soil Water Content ◽  
Water Uptake ◽  
Brackish Water ◽  
Deficit Irrigation ◽  
Root Zone ◽  
Root Water Uptake ◽  
Return Flows ◽  
Semi Arid

Water scarcity and quality degradation represent real threats to economic, social, and environmental development of arid and semi-arid regions. Drip irrigation associated to Deficit Irrigation (DI) has been investigated as a water saving technique. Yet its environmental impacts on soil and groundwater need to be gone into in depth especially when using brackish irrigation water. Soil water content and salinity were monitored in a fully drip irrigated potato plot with brackish water (4.45 dSm−1) in semi-arid Tunisia. The HYDRUS-1D model was used to investigate the effects of different irrigation regimes (deficit irrigation (T1R, 70% ETc), full irrigation (T2R, 100% ETc), and farmer’s schedule (T3R, 237% ETc) on root water uptake, root zone salinity, and solute return flows to groundwater. The simulated values of soil water content (θ) and electrical conductivity of soil solution (ECsw) were in good agreement with the observation values, as indicated by mean RMSE values (≤0.008 m3·m−3, and ≤0.28 dSm−1 for soil water content and ECsw respectively). The results of the different simulation treatments showed that relative yield accounted for 54%, 70%, and 85.5% of the potential maximal value when both water and solute stress were considered for deficit, full. and farmer’s irrigation, respectively. Root zone salinity was the lowest and root water uptake was the same with and without solute stress for the treatment corresponding to the farmer’s irrigation schedule (273% ETc). Solute return flows reaching the groundwater were the highest for T3R after two subsequent rainfall seasons. Beyond the water efficiency of DI with brackish water, long term studies need to focus on its impact on soil and groundwater salinization risks under changing climate conditions.

scholarly journals Water and salt transport in daily irrigated root zone.

1987 ◽  
Vol 35 (3) ◽  
pp. 395-406
Author(s):  
C. Dirksen
Keyword(s):  
Soil Water ◽  
Water Uptake ◽  
Gamma Ray ◽  
Root Zone ◽  
Root Water Uptake ◽  
Salt Transport ◽  
Soil Water Retention ◽  
Transport Models ◽  
Leaching Fraction ◽  
Water Contents

With closed, high-frequency irrigation systems, the water supply can be tailored to the instant needs of plants. To be able to do this optimally, it is necessary to understand how plants interact with their environment. To study water uptake under a variety of non-uniform conditions in the root zone, lucerne was grown in laboratory soil columns with automated gamma ray attenuation, tensiometer and salinity sensor equipment to measure soil water contents, pressure potentials and osmotic potentials, respectively. The columns were irrigated with water of different salinity at various frequencies and leaching fractions. This paper presents results obtained in a column irrigated daily with water of conductivity 0.33 S/m (h0 = -13.2 m) at a target leaching fraction of 0.08. This includes the drying and wetting patterns under daily irrigations in deficit and excess of evapotranspiration, respectively. After 230 days the salination of the column had still not reached a steady state. Salinity increased rapidly with depth and root water uptake was shallow for the deep-rooting lucerne. Water and salt transport under daily irrigation cannot be described without taking hysteresis of soil water retention into account. The data presented are suitable for testing various water uptake models, once numerical water and salt transport models of the required complexity are operational. (Abstract retrieved from CAB Abstracts by CABI’s permission)

scholarly journals Towards understanding tree root profiles: simulating hydrologically optimal strategies for root distribution

2001 ◽  
Vol 5 (4) ◽  
pp. 629-644 ◽  
Author(s):  
M. T. van Wijk ◽  
W. Bouten
Keyword(s):  
Water Uptake ◽  
Root Distribution ◽  
Root Zone ◽  
Evolutionary Game ◽  
Optimal Strategies ◽  
Single Root ◽  
Root Interactions ◽  
Model Configuration ◽  
The One ◽  
Root Distributions

Abstract. In this modelling study differences in vertical root distributions measured in four contrasting forest locations in the Netherlands were investigated. Root distributions are seen as a reflection of the plant’s optimisation strategy, based on hydrological grounds. The "optimal" root distribution is defined as the one that maximises the water uptake from the root zone over a period of ten years. The optimal root distributions of four forest locations with completely different soil physical characteristics are calculated using the soil hydrological model SWIF. Two different model configurations for root interactions were tested: the standard model configuration in which one single root profile was used (SWIF-NC), and a model configuration in which two root profiles compete for the same available water (SWIF-C). The root profiles were parameterised with genetic algorithms. The fitness of a certain root profile was defined as the amount of water uptake over a simulation period of ten years. The root profiles of SWIF-C were optimised using an evolutionary game. The results showed clear differences in optimal root distributions between the various sites and also between the two model configurations. Optimisation with SWIF-C resulted in root profiles that were easier to interpret in terms of feasible biological strategies. Preferential water uptake in wetter soil regions was an important factor for interpretation of the simulated root distributions. As the optimised root profiles still showed differences with measured profiles, this analysis is presented, not as the final solution for explaining differences in root profiles of vegetation but as a first step using an optimisation theory to increase understanding of the root profiles of trees. Keywords: forest hydrology, optimisation, roots

Root length density and water uptake in cereals and grain legumes: how well are they correlated

1987 ◽  
Vol 38 (3) ◽  
pp. 513 ◽  
Author(s):  
AP Hamblin ◽  
D Tennant
Keyword(s):  
Water Uptake ◽  
Root Length ◽  
Root Zone ◽  
Root Length Density ◽  
Genotypic Variation ◽  
Root Water Uptake ◽  
Grain Legumes ◽  
Rooting Depth ◽  
Rates Of Change ◽  
Axial Resistance

Total root length per unit ground area (La) is often considered to be directly related to the amount and rate of water uptake. Experiments were conducted to compare the water use of spring wheat, barley, lupin (L. angustifolius) and field pea on four differing soil types in drought-stressed conditions. The La values of cereals were consistently five to ten times as large as those of grain legumes, whereas the aboveground biomass was sim~iar and never greater than twice that of the grain legumes. Growing-season water loss (WL) from the soil profile was very similar for wheat and lupins, despite this big difference in root length. Soil evaporation may have been greater under lupins, but when crop water uptake was compared for the period when leaf area was greatest, rates of change in soil water content within the root zone were still similar and were not well correlated with La. Specific root water uptake (Ur) was consistently greater for lupin than wheat. Maximum rooting depth was better correlated with WL than was La in all cases. Higher Ur values in lupin and pea may be related to their large and abundant metaxylem vessels, which give much lower axial resistance than in cereals. These results provide strong evidence for genotypic variation in root morphology, density and root extension between dicotyledenous and monocotyledenous species. They also indicate that La is not necessarily the root morphological characteristic most responsible for efficiency of water uptake in drought-stressed environments.

Simulation of soil water dynamics in structured heavy soils with respect to root water uptake

Biologia ◽  
2006 ◽  
Vol 61 (19) ◽  
Author(s):  
David Zumr ◽  
Michal Dohnal ◽  
Miroslav Hrnčíř ◽  
Milena Císlerová ◽  
Tomáš Vogel ◽  
...  
Keyword(s):  
Water Uptake ◽  
Nitrogen Fertilization ◽  
Drip Irrigation ◽  
Soil Profile ◽  
Water Regime ◽  
Root Zone ◽  
Root Water Uptake ◽  
Water Dynamics ◽  
Preferential Pathways ◽  
The Impact

AbstractIn agricultural lands has the soil moisture uptake from the root system a significant effect on the water regime of the soil profile. In texturally heavy soils, where preferential pathways are present, infiltrated precipitation and irrigation water with diluted fertilizers quickly penetrate to a significant depth and often reach an under-root zone or even the ground-water level. Such a scenario is likely to happen during long summer periods without rain followed by heavy precipitation events, when a part of the water may flow through desiccated cracks.Since 2001 the effects of drip irrigation and nitrogen fertilization of potatoes (Solanum tuberosum L., cultivar Agria) have been monitored within the frame of a research project at the experimental site Valecov (Czech Republic). Based upon the measured data an attempt has been made to simulate the water regime of the soil profile at a selected experimental plot, considering the impact of preferential flow and root water uptake. The dual-permeability simulation model S_1D_Dual (VOGEL et al., 2000) was used for the simulation. The soil hydraulic parameters were inversely determined using Levenberg-Marquardt method. Measured and simulated pressure heads were utilized in the optimization criterion. The scaling approach was applied to simplify the description of the spatial variability of the soil profile.The results of simulations demonstrate that during particular rainfall events the water reaches significant depths of the soil profile via preferential pathways. The effect of the root zone is dominant during dry periods, when capillary water uptake from the layers below roots becomes important. This should be taken in account into the optimization of the drip irrigation and nitrogen fertilization schedule.

scholarly journals Parameterization of Root Water Uptake Models Considering Dynamic Root Distributions and Water Uptake Compensation

2017 ◽  
Vol 17 (1) ◽  
pp. 160125 ◽  
Author(s):  
Gaochao Cai ◽  
Jan Vanderborght ◽  
Valentin Couvreur ◽  
Cho Miltin Mboh ◽  
Harry Vereecken
Keyword(s):  
Water Uptake ◽  
Root Water Uptake ◽  
Root Distributions

scholarly journals Water Footprint and Crop Water Usage of Oil Palm (Eleasis guineensis) in Central Kalimantan: Environmental Sustainability Indicators for Different Crop Age and Soil Conditions

Water ◽  
2018 ◽  
Vol 11 (1) ◽  
pp. 35 ◽  
Author(s):  
Lisma Safitri ◽  
Hermantoro Hermantoro ◽  
Sentot Purboseno ◽  
Valensi Kautsar ◽  
Satyanto Saptomo ◽  
...  
Keyword(s):  
Water Uptake ◽  
Oil Palm ◽  
Environmental Sustainability ◽  
Water Footprint ◽  
Root Zone ◽  
Root Water Uptake ◽  
Soil Types ◽  
Soil Conditions ◽  
Water Usage ◽  
Central Kalimantan

Various issues related to oil palm production, such as biodiversity, drought, water scarcity, and water and soil resource exploitation, have become major challenges for environmental sustainability. The water footprint method indicates that the quantity of water used by plants to produce one biomass product could become a parameter to assess the environmental sustainability for a plantation. The objective of this study is to calculate the water footprint of oil palm on a temporal scale based on root water uptake with a specific climate condition under different crop age and soil type conditions, as a means to assess environmental sustainability. The research was conducted in Pundu village, Central Kalimantan, Indonesia. The methodology adopted in carrying out this study consisted of monitoring soil moisture, rainfall, and the water table, and estimating reference evapotranspiration (ETo), root water uptake, and the oil palm water footprint. Based on the study, it was shown that the oil palm water usage in the observation area varies with different crop ages and soil types from 3.07–3.73 mm/day, with the highest contribution of oil palm water usage was in the first root zone which correlates to the root density distribution. The total water footprint values obtained were between 0.56 and 1.14 m3/kg for various plant ages and soil types. This study also found that the source of green water from rainfall on the upper oil palm root zone delivers the highest contribution to oil palm root water uptake than the blue water from groundwater on the bottom layer root zone.

Efficacy of Nonlinear Root Water Uptake Model for a Multilayer Crop Root Zone

2013 ◽  
Vol 139 (11) ◽  
pp. 898-910 ◽  
Author(s):  
Rohitashw Kumar ◽  
Vijay Shankar ◽  
Mahesh Kumar Jat
Keyword(s):  
Water Uptake ◽  
Root Zone ◽  
Root Water Uptake ◽  
Crop Root
Sign in / Sign up

Export Citation Format

Share Document