Search

Seasonal management of plant water status and the accompanying physiological responses are critical aspects of viticultural production. Presently, grapevine (Vitis vinifera, L.) water status is measured via in-season measurements of stem water potential or post-season analysis of must carbon isotope ratios, with the former limited by reliance on laborious measurements and the latter providing information post-season. Therefore, there is a gap in reliable, real-time measurements of plant water status. Technological advances in surface renewal measurement in vineyards have provided an economical and reliable method for measuring actual evapotranspiration of a vineyard. This experiment utilized surface renewal calculations to derive a novel index of grapevine water stress, the Priestly-Taylor index (β-index), and related it to measurements of stem water potential, leaf-gas exchange, and must carbon isotopes from three vineyards with differing irrigation strategies over two growing seasons. The sensible heat flux, latent heat flux and net radiation varied across these vineyards and affected the actual vineyard evapotranspiration measured. Likewise, the β-index was different across these vineyards and ranged from 1.7 to 2.1 in the Sacramento Valley of California to 0.5 to 1.2 in the Napa Valley of California. The β-index was related to stem water potential, net carbon assimilation and stomatal conductance (r2 = 0.42, r2 = 0.45, r2 = 0.33, respectively). Results indicated that the β-index was an indicator of real-time vineyard water status and a proxy for physiological responses in vineyards. The coupling of atmospheric controls on evapotranspiration with plant physiological responses makes β a powerful tool for irrigation management in large scale agrosytems.

The efficiency of irrigation, as well as optimization of nutrients, affect spinach yield in all growth stages. In this study, the sensitivity of spinach (early and mature yields) to shallow saline groundwater and the effect of fertigation treatments on mature yield were experimentally investigated. The sprinkler irrigation experiments were conducted on 0.47 ha of silty clay soil at the University of California Desert Research and Extension Center (DREC) in Imperial Valley, California. Twelve beds in the experimental field were chosen randomly to investigate the effect of three fertigation treatments on spinach yield. Three rates of urea ammonium nitrate (UAN-32) fertilizer; T1: 200 kg ha−1 (150%), T2: 133.3 kg ha−1 (100%), and T3: 66.7 kg ha−1 (50%) in four replicates were applied. Soil samples to depths of up to 120 cm were collected at baby leaves and mature harvesting dates (17th October and 19th November 2019, respectively) for salinity measurements. Additionally, soil matric potential through the 120 cm soil depth was measured and groundwater levels in five observation wells were recorded during the growing season. Results showed that average soil salinity at baby leaves harvesting stage through the top 60 cm active root zone depth ranged from 0.61 to 1.48 dS m−1, which is lower than the spinach salinity threshold limit (2 dS m−1), while the average groundwater depth was 1.90 m with salinity ranging from 6.35 to 10.60 dS m−1. Correlation analysis showed that the baby spinach leaves yield was weakly correlated (r = 0.40) to the average soil salinity in the top 60 cm soil depth. Although groundwater and top 60 cm soil salinity showed an increase at the mature yield harvesting stage, the mature yield was weakly correlated to soil salinity (p = 0.116). As the UAN-32 rate increased, the mature spinach yield increased. The mature spinach yields were 17.31, 14.00, and 12.54 ton ha−1 for T1, T2, and T3 fertigation treatments, respectively. However, only a 10% reduction in yield occurred in T3 treatment corresponding to a 50% reduction in UAN-32 rate by 66.7 kg ha−1. Based on the results of this study, shallow saline groundwater has little impact on spinach yield. In addition, the 50% increase in UAN-32 rate had a significant impact on mature spinach yield. The 150% UAN-32 rate resulted in an increase in spinach yield and could be used in arid and semiarid regions with similar conditions to the Imperial Valley but additional measures to minimize the leaching of nitrate from the root zone and to reduce the load of nitrogen in drainage water are needed to minimize the potential negative impact of over-fertigation on the environment.

HighlightsSubsurface drip irrigation (SDI) has continued to expand in irrigation area within the U.S. during the last 15 years.Research with SDI continues for multiple crop types (fiber, grain and oilseed, horticultural, forage, and turf).SDI usage on many crops has matured through research and development of appropriate strategies and technologiesDespite some persistent challenges to successful use of SDI, important opportunities exist for further adoption.Abstract. Subsurface drip irrigation (SDI) offers several advantages over alternative irrigation systems when it is designed and installed correctly and when best management practices are adopted. These advantages include the ability to apply water and nutrients directly and efficiently within the crop root zone. Disadvantages of SDI in commercial agriculture relative to alternative irrigation systems include greater capital cost per unit land area (except for small land parcels), unfamiliar management and maintenance protocols that can exacerbate the potential for emitter clogging, the visibility of system attributes (components and design characteristics) and performance, and the susceptibility to damage (i.e., rodents and tillage) of the subsurface driplines. Despite these disadvantages, SDI continues to be adopted in commercial agriculture in the U.S., and research efforts to evaluate and develop SDI systems continue as well. This article summarizes recent progress in research (2010 to 2020) and the status of commercial adoption of SDI, along with a discussion of current challenges and future opportunities. Keywords: Drip Irrigation, Irrigation, Irrigation systems, Microirrigation, SDI, Water management.

In California, daily crop evapotranspiration (ETc) is commonly estimated using near-real-time, standardized reference evapotranspiration (ETo) calculated from ground-based meteorological data and crop coefficient (Kc) values that adjust for the difference between ETo and ETc. However, using ETo calculated from forecast rather than near-real-time meteorological data provides more timely information to growers, farm managers, urban water users, irrigation practitioners, and water purveyors to anticipate water demand for the upcoming days. This is particularly important for water allocation and delivery planning and for irrigation scheduling decisions. Forecast ETo is also relevant for scientific research for developing methods and tools enabling more resource-efficient water use for agricultural production and urban landscapes. Verifying the reliability of ETo forecast models for various climatic conditions is crucial for promoting the broad adoption and use of ETo predictions for weather-based adaptive water management and prospective irrigation scheduling. The US National Weather Service (NWS) has released a product called forecast reference evapotranspiration (FRET) that provides ETo forecasts at a 2.5-km grid resolution for the entire continental US. In this study, comparisons were made between ETo forecasts from FRET and observed ETo values from the California Irrigation Management Information System (CIMIS) for a total of 78 days during the peak irrigation water demand period of 2019, which corresponded to the midseason period for major crops. FRET ETo forecasts and CIMIS ETo observations (calculated from measured weather parameters) were compared for 15 CIMIS station locations to represent a variety of weather conditions of some major agricultural production and urban areas in California. Air temperature, dew point temperature, wind speed, and solar radiation data were collected from NWS and CIMIS and analyzed to assess the accuracy of predicted weather variables and FRET ETo forecasts. The FRET data consisted of 1, 3, 5, and 7-day forecasts of weather parameters and calculated ETo values; these were compared with the corresponding observed daily weather and ETo data from CIMIS in order to statistically evaluate FRET performance. The comparison among forecast and measured weather variables revealed a good match for maximum air temperature (R2 between 0.98 and 1.00), minimum air temperature (R2 > 0.91), dew point temperature (R2 between 0.7 and 1.00), and wind speed (R2 between 0.66 and 0.99); less accurate results were obtained for solar radiation (R2 between 0.21 and 0.87). The analysis also showed a good correlation between FRET ETo forecast data and observed CIMIS ETo data (R2 between 0.93 and 1.00 and root mean square error (RMSE) was less than 1 mm · day−1) for the majority of the selected stations, with some differences that were likely due to the climatic conditions of specific locations. This suggests that FRET ETo forecasts provide reliable information for predicting near-future water demand and improving irrigation water management in California. The comparisons showed a good match for most of the 15 CIMIS stations, and the FRET model may potentially provide accurate ETo forecasts in similar semiarid and subhumid areas elsewhere. Weekly irrigation schedule examples are provided in the Appendix to illustrate the use of FRET ETo forecasts in combination with site-specific information on soil hydraulic properties and irrigation system performance for prospective irrigation scheduling of some specialty crops and urban landscapes. The information provided in this article can help improve the water management efficiency of high-frequency agricultural irrigation systems and urban sprinkler systems in California and other locations with similar climates. It also offers a less expensive method to obtain ETo data in countries that do not have ETo station networks, because it offers an alternative to installing and maintaining ETo stations in agricultural and urban areas where it is difficult to find acceptable surfaces for developing reliable ETo information.

Canal seepage losses can contribute significantly to groundwater aquifers in arid and semi-arid regions worldwide. In addition, surface water evaporation and evapotranspiration from adjacent riparian vegetation directly affect surface water availability across these regions. This study aims to evaluate interactions between irrigation canals and the Nile Delta groundwater aquifer in Egypt under four operational scenarios: (i) decreased stream flows in the four main diversion canals associated with upper Nile diversions and climate change, (ii) concrete lining of irrigation canals, (iii) combined lining and use of Photo-Voltaic (PV) Solar Panel covers on canals and (iv) enclosure of the canals in closed conduits. We investigated the effects of these scenarios on regional groundwater supplies and levels using MODFLOW and water budget analyses. Decreased streamflow (scenario 1) resulted in decreased aquifer recharge (from 732 910 to 483 800 m3 day−1) and lower groundwater levels as compared to the base case (present) conditions. Moreover, groundwater flows from the aquifer to the four main canals noticeably increased from 23 176 to 79 364 m3 day−1. Water budget analyses associated with canal lining scenarios (2, 3, & 4) indicated that canal leakage to the aquifer accounted for 146 582, 146 582, and 73 291 m3 day−1 respectively. The changes in canal efficiencies reached 29.3%, 67.1%, 75.3%, and 91.8% while the changes in aquifer recharge efficiencies were 66%, 20%, 20%, and 10% for the four scenarios, respectively. Overall, we found that canals lining is likely the most suitable solution for managing water resources in the Nile Delta. Further aspects to be considered in future studies include the loss of biodiversity along streams embankments due to channel lining.

Item does not contain fulltext OBJECTIVE: Palliative pelvic exenteration (PPE) is a technically complex operation with high morbidity and mortality rates, considered in patients with limited life expectancy. There is little evidence to guide practice. We performed a systematic review to evaluate the impact of PPE on symptom relief and quality of life (QoL). METHODS: A systematic review was conducted according to the PRISMA guidelines using Ovid MEDLINE, EMBASe, and PubMed databases for studies reporting on outcomes of PPE for symptom relief or QoL. Descriptive statistics were used on pooled patient cohorts. RESULTS: Twenty-three historical cohorts and case series were included, comprising 509 patients. No comparative studies were found. Most malignancies were of colorectal, gynaecological and urological origin. Common indications for PPE were pain, symptomatic fistula, bleeding, malodour, obstruction and pelvic sepsis. The pooled median postoperative morbidity rate was 53.6% (13-100%), the median in-hospital mortality was 6.3% (0-66.7%), and median OS was 14 months (4-40 months). Some symptom relief was reported in a median of 79% (50-100%) of the patients, although the magnitude of effect was poorly measured. Data for QoL measures were inconclusive. Five studies discouraged performing PPE in any patient, while 18 studies concluded that the procedure can be considered in highly selected patients. CONCLUSION: Available evidence on PPE is of low-quality. Morbidity and mortality rates are high with a short median OS interval. While some symptom relief may be afforded by this procedure, evidence for improvement in QoL is limited. A highly selective individualised approach is required to optimise the risk:benefit equation.

There is evidence that children with neurodevelopmental disorders may exhibit atypical responses to stress and alterations in concentrations and diurnal secretion of stress hormones. We assessed diurnal profiles and stress responses of salivary cortisol and alpha-amylase (sAA) in children with attention-deficit hyperactivity disorder (ADHD), autism spectrum disorder (ASD) and specific learning disorder (SLD) compared to typically developing children (TD). A total of 157 children of both sexes, aged between 6 and 12 years old, took part in the study distributed into four groups: ADHD (N = 34), ASD (N = 56), SLD (N = 43) and TD (N = 24). Salivary samples were collected at three time points during a day, as well as before and 5 min after an academic performance test and a moral cognition task. ADHD children had lower evening and diurnal sAA levels, adjusted for age. Also, ASD children showed lower diurnal sAA secretion, adjusted for age. The mean percentage change for salivary cortisol and sAA after both tests did not differ between the groups. In conclusion, we demonstrated alterations in diurnal autonomic functioning in children with ADHD and ASD, while hypothalamic–pituitary–adrenal axis functioning did not differ between the clinical and the comparison groups. © 2020 John Wiley & Sons Ltd.

No abstract available

Agricultural drainage plays an important role worldwide in food production and conservation of soil resources, while safeguarding investments in agricultural production and irrigation projects. It can improve crop yields and land productivity, especially on poorly drained soils and in cases of prolonged waterlogging. Both the subsurface drainage materials and the installation techniques used have a long history dating to prehistoric times. Over time, new subsurface drainage materials, installation techniques and modernized equipment were being developed continuously to take advantage of technological advances provided through research and development, while the planning and organization of the implementation process were improved. Today’s new materials and improved installation methods can offer solutions to problems still unsolved, while sometimes creating new ones. This paper considers the evolution of basic subsurface drainage materials and their installation techniques as they developed and adapted over time as well as possible future trends in drainage system design and application.

Evapotranspiration is the transfer of water from the earth's surface to the atmosphere. It comprises the sum of water losses to atmosphere due to the processes of evaporation of moisture from soil, water bodies and wet plant canopies, and the transpiration of water from plants. Forecasts of this crucial component of the hydrologic cycle can be very valuable for growers, farm managers, irrigation practitioners, water resource planners and managers, and reservoir operators for their planning, allocation, delivery and scheduling decisions, as well as to hydrologic scientists for research purposes. Verifying the reliability of models’ forecasts is among the critical tasks for development and performance evaluation of physical models. In fact, the verification allows understanding the models’ behavior, and evaluating their applicability and dependability. The US National Weather Service (NWS) has released a product that provides forecasts of reference evapotranspiration (FRET) at 2.5-km grid resolution for the entire continental US. In this study, a comparison is made between ETo estimates from FRET and ETo values calculated by the California Irrigation Management Information System (CIMIS) for 68 days during summer 2019. Both the FRET forecasts and ETo values were obtained from NWS and CIMIS, respectively, on the basis of 15 CIMIS locations that are representative of different climatic conditions in California. In addition, air temperature, dew point temperature, relative humidity, wind speed, and vapor pressure deficit (VPD) data were also collected/calculated from the NWS and CIMIS websites to analyze the sensitivity of FRET forecasts to predictions of these parameters. All FRET forecasts were performed with timescales of 1, 3, 5 and 7 days. Statistical indices were calculated to assess the dependability of FRET values. They showed a good correlation of the FRET model outputs with CIMIS ETo data, with some differences depending on the climatic characteristics of selected weather stations’ locations, suggesting that FRET data could be valuable for anticipating near-future water demand and improve irrigation management in California.

Yield and production functions of sunflower (Helianthus annuus) were evaluated under full and deficit irrigation practices with the presence of shallow saline groundwater in a semi-arid region in the Imperial Valley of southern California, USA. A growing degree day (GDD) model was utilized to estimate the various growth stages and schedule irrigation events throughout the growing season. The crop was germinated and established using overhead irrigation prior to the use of a subsurface drip irrigation (SDI) system for the remainder of the growing season. Four irrigation treatments were implemented: full irrigation (100% full sunflower crop evapotranspiration, ETC), two reduced irrigation scenarios (95% ETC and 80% ETC), and a deficit irrigation scenario (65% ETC). The salinity of the irrigation water (EC) (Colorado River water) was nearly constant at 1.13 dS&middot, m&minus, 1 during the growing season. The depth to groundwater and groundwater salinity (ECGW) were continuously monitored in five 3 m deep observation wells. Depth to groundwater fluctuated slightly under the full and reduced irrigation treatments, but drastically increased under deficit irrigation, particularly toward the end of the growing season. Estimates of ECGW ranged from 7.34 to 12.62 dS&middot, 1. The distribution of soil electrical conductivity (ECS) and soil matric potential were monitored within the active root zone (120 cm) at selected locations in each of the four treatments. By the end of the experiment, soil salinity (ECS) across soil depths ranged from 1.80 to 6.18 dS&middot, 1. The estimated groundwater contribution to crop evapotranspiration was 9.03 cm or approximately 16.3% of the ETC of the fully irrigated crop. The relative yields were 91.8%, 82.4%, and 83.5% for the reduced (95% and 80% ETC) and deficit (65% ETC) treatments, respectively, while the production function using applied irrigation water (IW) was: yield = 0.0188 &times, (IW)2 &minus, 15.504 &times, IW + 4856.8. Yield reduction in response to water stress was attributed to a significant reduction in both seed weight and the number of seed produced resulting in overall average yields of 2048.9, 1879.9, 1688.1, and 1710.3 kg&middot, ha&minus, 1 for the full, both reduced, and deficit treatments, respectively. The yield response factor, ky, was 0.63 with R2 = 0.745 and the irrigation water use efficiencies (IWUE) were 3.70, 3.57, 3.81, and 4.75 kg&middot, 1&middot, mm&minus, 1 for the full, reduced, and deficit treatments, respectively. Our results indicate that sunflowers can sustain the implemented 35% deficit irrigation with root water uptake from shallow groundwater in arid regions with a less than 20% reduction in yield.

International audience; The Ukrainian crisis of November 2013 has led to the proclamation of independence of the Republic of Crimea in March 2014, and its attachment to Russia. This attachment, recognised by Russia and contested by a large number of Western countries, triggered an international crisis between the Russian Federation and the West (European Union, United States of America, et cetera). As a means of applying pressure on Russia, Western countries decided to launch a set of international sanctions. This paper’s goal is to assess on sanctions effects on Russian and European economies. Thus, a country structural vector autoregressive (CSVAR) model is used in order to witness the impact of a sanction shock on considered economies. To our best knowledge, this paper is the first to use a CSVAR model to study the economic growth effects of anti-Russian sanctions on the considered economies. The economic conflict repercussions are revealed on the Euro Area (19 countries), on the six biggest trade partners of Russia as a lone entity, and finally on the six biggest trade partners of Russia separately. Results witness that the shock’s effects are quite different whether a sum of GDP is used or not. In addition, results reveal that Russia is the most impacted by sanctions with a quarter-on-quarter GDP growth decrease of 3.25% after 3 quarters. Yet, European economies are also negatively impacted by sanctions, even if the impact is much weaker: -0.075% for Finland, -0.025% for France, -0.0125% for Germany, -0.012% for Italy, and -0.063% for Poland. As a consequence, we can say that the own coercive measures of European countries have a negative impact on their economies.

The ability to monitor the flocculation, aggregation and settling of micro and nano-sized particles is important for many environmental, chemical, biological and biomedical processes. However, standard approaches such as dynamic light scattering or absorption spectroscopy require sample dilution for characterization of highly concentrated samples. In this model study a new method using total internal reflection (TIR) is demonstrated to directly detect aggregates in highly-concentrated, strongly-absorbing samples of aqueous gold nanoparticles without sample dilution or pretreatment. Aggregation of the gold nanoparticles is induced by changing solution pH or by increasing ionic strength. Results obtained using the new sensor with no dilution agree with the post-dilution results obtained by absorption spectroscopy, dynamic light scattering, and zeta potential measurements. This validation of the sensor by standard methodologies is important because earlier work with sensitive detection of aggregates in non-absorbing polystyrene nanoparticles precluded the use of standard methodologies.

Nitrogen (N) accounts for more than 80% of the total mineral nutrients absorbed by plants and it is the most widely limiting element for crop production, particularly under water deficit conditions. For a comprehensive understanding of sunflower Helianthus annuus N uptake under deficit irrigation conditions, experimental and numerical simulation studies were conducted for full (100% ETC) and deficit (65% ETC) irrigation practices under the semi-arid conditions of the Imperial Valley, California, USA. Plants were established with overhead sprinkler irrigation before transitioning to subsurface drip irrigation (SDI). Based on pre-plant soil N testing, 39 kg ha&minus, 1 of N and 78 kg ha&minus, 1 of P were applied as a pre-plant dry fertilizer in the form of monoammonium phosphate (MAP) and an additional application of 33 kg ha&minus, 1 of N from urea ammonium nitrate (UAN-32) liquid fertilizer was made during the growing season. Soil samples at 15-cm depth increments to 1.2 m (8 layers, 15 cm each) were collected prior to planting and at three additional time points from two locations each in the full and deficit irrigation treatments. We used HYDRUS/2D for the simulation in this study and the model was calibrated for the soil moisture parameters (&theta, s and &theta, r), the rate constant factors of nitrification (the sensitive parameter) in the liquid and solid states (&mu, w,3, and &mu, s,3). The HYDRUS model predicted cumulative root water uptake fluxes of 533 mm and 337 mm for the 100% ETC and 65% ETC, respectively. The simulated cumulative drainage depths were 23.7 mm and 20.4 mm for the 100% ETC and 65% ETC which represented only 4% and 5% of the applied irrigation water, respectively. The soil wetting profile after SDI irrigation was mostly around emitters for the last four SDI irrigation events, while the maximum values of soil moisture in the top 30 cm of the soil profile were 0.262 cm3 cm&minus, 3 and 0.129 cm3 cm&minus, 3 for 100% ETC and 65% ETC, respectively. The 16.5 kg ha&minus, 1 (NH2)2CO (50% of the total N) that was applied during the growing season was completely hydrolyzed to NH4+ within 7 days of application, while 4.36 mg cm&minus, 1 cumulative decay was achieved by the end of the 98-day growing season. We found that 86% of NH4+ (74.25 mg cm&minus, 1) was nitrified to NO3&minus, while 14% remained in the top 50 cm of the soil profile. The denitrification and free drainage of NO3&minus, were similar for 100% ETC and 65% ETC, and the maximum nitrate was drained during the sprinkler irrigation period. By the end of the growing season, 30.8 mg cm&minus, 1 of nitrate was denitrified to N2 and the reduction of nitrate plant uptake was 17.1% for the deficit irrigation section as compared to the fully irrigated side (19.44 mg cm&minus, 1 vs. 16.12 mg cm&minus, 1). This reduction in N uptake due to deficit irrigation on sunflower could help farmers conserve resources by reducing the amount of fertilizer required if deficit irrigation practices are implemented due to the limited availability of irrigation water.

Author(s): Long, Rachael; Gulya, Tom; Light, Sarah; Bali, Khaled; Mathesius, Konrad; Meyer, Roland D | Abstract: California's Sacramento Valley is world renowned as a premier location for sunflower seed production. Hybrid sunflower seed production must follow strict standards to meet California state export mandates for all certified sunflower fields. These include crop rotation, weed and disease control, simultaneous bloom of male and female lines, and field isolation in time and space to ensure varietal purity.This publication addresses all aspects of production for growing certified seed including:Land Selection, Crop Rotation, Seedling Rate and Timing, Pollination, Soil Fertility and FertilizersIrrigation, Pest Management, Abiotic Disorders, Harvesting and Processing, Cleaning, Grading, and Marketing

Author(s): Long, Rachael; Leinfelder-Miles, Michelle; Mathesius, Konrad; Bali, Khaled; Light, Sarah; Galla, Mariano; Mueller, Shannon; Fulton, Allan; Clark, Nicholas; Meyer, Roland D | Abstract: In California, garbanzos are grown primarily as a high-end specialty product for the canning industry. To meet this market demand, canning-quality garbanzo beans must be creamy colored, have a large, uniform seed size, and maintain firmness after canning with no seed splitting or skin peeling. There is also a market for the large seeded, dry-packaged garbanzo beans. California’s Mediterranean climate provides ideal growing conditions for this market segment. This publication covers production from seed selection to harvesting and markets.

This study was carried out to develop a model to explore the economic viability of subsurface drip irrigation (SDI) for alfalfa production in the major alfalfa production regions of California. Data from previously published studies on alfalfa under drip irrigation were applied to establish the relationship between hay yield and seasonal water use. A correction factor was defined to adjust the potential impacts of SDI due to regional differences in yield potential. A partial economic analysis was developed to assess economic benefits of SDI in alfalfa. The model predicted an additional 7.9 Mg ha−1 yield as a result of switching from surface flood irrigation to SDI, averaged across the principal alfalfa-growing counties and regions in California. The hay yield improvements predicted by the model are in good agreement with the preliminary reports of improved hay yields from the 12 commercial farmers who have implemented SDI in Sacramento Valley, Low Desert, and Southern San Joaquin Valley regions. While the proposed model illustrated the potential profitability of SDI in alfalfa in several regions, further on-farm experience and analysis would be required to confirm these results in practice. Copyright © 2016 John Wiley & Sons, Ltd.

Evapotranspiration (ET) is a major hydrologic flux in water resources planning and irrigation management. While recent advances in remote sensing (RS) have enabled availability of high spatial and temporal resolution ET data, a lack of information related to error in the estimations has made it challenging to use this data for on-farm irrigation management decision making. In this study, three commonly used single-source RS based ET models (pySEBAL — a new version of the Surface Energy Balance Algorithm for Land; SEBS — Surface Energy Balance System algorithm; and METRIC — Mapping Evapotranspiration at High Resolution with Internalized Calibration) were used to estimate daily actual evapotranspiration (ETa) for almonds, processing tomatoes, and maize in the Central Valley of California. Model evaluation was conducted by comparing the predicted ETa from RS with in-situ measured ETa using surface renewal. Results indicated that the RS-based ETa estimations for all three models were within acceptable levels of uncertainty and agreed well with surface renewal estimates except for the underestimation by pySEBAL and METRIC during early season growth stages of processing tomatoes. This underestimation was attributed to the lack of accuracy when using single source ET models under lower vegetation cover condition (when ET is dominated by soil evaporation). Better estimates of ETa with pySEBAL and METRIC were detected at full cover, which explains the applicability of these two models to irrigation management during peak crop water demand. SEBS performed the best among the three RS-based models for daily ETa estimation for all crops. This suggests that SEBS-based ETa estimates can be adopted in operational irrigation management programs for farms that have not installed in field ETa sensors such as Tule Sensors (Tule Technologies Inc.). In addition, RS based ET is spatially distributed which can help to identity spatial variability between different irrigation zones.

Background:Functional limitation and inactivation are the most important problems in children with Juvenil Idiopatik Artrit (JIA).Objectives:The aim of this study was to link and allocate items of Childhood Health Assessment Questionnaire (CHAQ) with activity and participation based on International Classification of Functioning, Disability and Health (ICF). The other aim was to examine the relationship between the pain and activity and participation determined on the basis of CHAQ with Juvenil Idiopatik Artrit (JIA).Methods:Thirty-seven children and adolescents (26 girls, 11 boys, mean age=11.75±4.04 years) were included. The mean BMI of the participants was 19.61±4.52 kg / cm2. Inclusion criteria: To be diagnosed with JIA according to ILAR classification. Being in the 6-18 age range. To be stable in drug use for at least 3 months or longer. Exclusion criteria:The presence of another disease. Intraarticularsteroid injection or surgery in any joint in last 3 months. Evaluations were made by the same pediatric rheumatologist and physiotherapist (PT) by face to face interview method. Pain was evaluated by use of Numeric Rating Scale (NRS) (0=no, 10=worst) and disability by CHAQ. As CHAQ score increases, disability increases. CHAQ has 8 categories. The highest score for any question determines the score for that category. The items of CHAQ were linked with ICF codes and allocated with the ICF components by three PT. Original scoring of CHAQ allocated to ICF components was used in order to calculate scores of activity and participation in accordance with clinical data for 37 JIA. The 20th item in the “Reach” category is not included in the calculation as it contains the body function component of ICF. The data was analyzed using Pearson’s correlation coefficient.Results:Mean score of NRS was 3.52±2.34. Mean activity and participation score of CHAQ was 0.51±0.58, 0.70±1.10, respectively. Based on expert distinction, activity and participation categories of ICF were covered 24 and 5 items of CHAQ, respectively. Pain had moderate correlation with activity (r=0.595; p=0.002) and participation (r=0.604; p=0.001) for CHAQ. Activity had high correlation with participation (r=0.702; p=0.000).Conclusion:Pain in children and adolescents with JIA is an important parameter affecting activity and participation. Pain should be evaluated in all aspects due to the limitation of both activity and participation. CHAQ largely contains the activity component of ICF. The development of new questionnaire is needed to assess the participation of JIA children and adolescents in more detail.References:[1]Schanberg LE. Widespread pain in children: when is it pathologic? Arthritis Rheum 2003;48:2402-2405.Table 1.Linking and allocating items of CHAQItemsICF CodeICF ComponentDRESSING & GROOMINGDress, including tying shoelaces and doing buttons?d5402AShampoo his/her hair?d5100ARemove socks?d5403ACut fingernails?d520AARISINGStand up from a low chair or floor?d4103AGet in and out of bed or stand up in crib?d4100AEATINGCut his /her own meat?d550ALift a cup or glass to mouth?d4402AOpen a new cereal box?d440AWALKINGWalk outdoors on flat ground?d450AClimb up five steps?d4551AHYGIENEWash and dry entire body?d510ATake a tub bath?dd410AGet on and off the toilet or potty chair?d4103ABrush teeth?d5201AComb/brush hair?d5202AREACHReach and get down a heavy object from just above his/her head?d4452ABend down to pick up clothing or a piece of paper from the floor?d4105APull on a sweater over his/her head?d5400ATurn neck to look back over shoulder?b7101Body FunctionGRIPWrite or scribble with pen or pencil?d170AOpen car doors?d4450AOpen jars which have been previously opened?d4453ATurn faucets on and off?d4402APush open a door when he/she to turn a door knob?d4453AACTIVITIESRun errands and shop?d6200PGet in and out of car or toy car or school?d4702PRide bike or tricycle?d4750PDo household choresd6402PRun and play?d9201PA:Activity, P:ParticipationDisclosure of Interests:None declared

Background:In the literature, it was reported that children with with Familial Mediterranean fever (FMF) have lower functional capacity and muscle strength than healthy children. With reduced functional capacity, daily activities are negatively affected. The individual starts to adopt an inactive lifestyle and decreases in muscle strength are observed. A vicious circle occurs and results in exacerbation of symptoms and worse quality of life.Objectives:The aim of this study is to investigate the effect of gender on dynamic muscular endurance, physical activity and quality of life with FMF.Methods:Forty-eight children and adolescents (26 girls, 22 boys, mean age=12.43±3.04 years, age range=7-18 years) were included. Exclusion criteria:The presence of another disease. Intraarticularsteroid injection or surgery in any joint in the last 3 months. Evaluations were made by the same pediatric rheumatologist and physiotherapist by face to face interview method. Dynamic muscle endurance was evaluated by use of curl up test (30 sec), push up test (30 sec) and one-legged stationary hop test (15 sec); physical activity level by Physical Activity Questionnaire and quality of life by Pediatric Quality of Life Inventory (PedsQL) 3.0 Arthritis Module. Physical Activity Questionnaire contains nine items and evaluates physical activities in last seven days and frequency of these activities. As score increases, level of physical activity increases. In this study, child and parent forms of PedsQL were used to evaluate the quality of life. High scores mean high quality of life. Independent Samples Test was used in the analysis because the data fit the normal distribution.Results:Difference was significant in Physical Activity Questionnaire (p=0.028) in favor of girl gender whereas in child form (p=0.017) and parent form (p=0.040) of PedsQL (p=0.003) in favor of boy gender.Conclusion:We see that the physical activity are lower in children and adolescents with FMF who have a gender of girls and, accordingly, lower quality of life. Therefore, we believe that these individuals should increase their physical activities.References:[1]Gualano B, S´a Pinto AL, Perondi B, Leite Prado DM, Omori C, Almeida RT, Sallum AM, Silva CA. Evidence for prescribing exercise as treatment in pediatric rheumatic diseases. Autoimmun Rev 2010;9(8):569-573.[2]Alayli G, Durmus D, Ozkaya O, Sen HE, Nalcacioglu H, Bilgici A, Kuru O. Functional Capacity, Strength, and Quality of Life in Children and Youth With Familial Mediterranean Fever. Pediatric Physical Therapy 2014;26(3):347-352.Table 1.Demographic characteristicsVariablesGirls (n=26)Boys (n=22)M±SDM±SDAge (years)12.96±2.9111.86±3.24Body weight (kg)42.76±12.5540.17±11.89Height (m)1.50±0.131.48±0.15BMI (kg/m2)18.25±2.9017.85±3.39Age of onset (years)7.57±4.077.22±3.99Dose of colchicine (per day)1.18±0.601.63±0.68Duration of treatment (years)5.30±2.904.61±3.34C-reactive protein (mg/dl)0.88±2.281.25±2.91Pras et al severity score6.35±2.685.31±2.60n (%)n (%)FMF in the family (Yes/No)4(15.4)/16(61.5)12(54.5)/10(45.5)Arthritis (Yes/No)9(34.6)/17(65.4)6(27.3)/16 (72.7)Arthralgia (Yes/No)20(76.9)/6(23.1)14(63.6)/ 8(36.4)Knee (Yes/No)6(23.1)/20(76.9)7(31.8)/15 (68.2)Elbow (Yes/No)1(3.8)/25(96.2)0(0)/22(100)Ankle (Yes/No)6(23.1)/20(76.9)7(31.8)/15(68.2)Hand (Yes/No)1(3.8)/25(96.2)1(4.5)/21(95.5)Table 2.Comparison of data in terms of genderVariablesGirls (n=26)Boys (n=22)p*M±SDM±SDCurl Up Test (repeat)10.70±3.5812.80±3.660.075Push Up Test (repeat)10.55±5.0611.75±6.290.511One-legged Stationary Hop Test (repeat)37.60±12.7435.35±6.020.480Physical Activity Questionnaire16.93±5.7020.70±5.770.028PedsQL- child form19.15±13.4810.68±9.380.017PedsQL- parent form22.30±17.8513.04±11.060.040Disclosure of Interests:None declared

Author(s): Orloff, Steve; Putnam, Dan; Bali, Khaled | Abstract: Las condiciones de sequia requieren un enfoque completamente nuevo para la produccion de cultivos y eso incluye a la alfalfa. Conozca como mantener las perdidas de cultivos de alfalfa a un nivel minimo durante un regimen de agua limitada.

California is a global leader in the agricultural sector and produces more than 400 types of commodities. The state produces over a third of the country’s vegetables and two-thirds of its fruits and nuts. Despite being highly productive, current and future climate change poses many challenges to the agricultural sector. This paper provides a summary of the current state of knowledge on historical and future trends in climate and their impacts on California agriculture. We present a synthesis of climate change impacts on California agriculture in the context of: (1) historic trends and projected changes in temperature, precipitation, snowpack, heat waves, drought, and flood events; and (2) consequent impacts on crop yields, chill hours, pests and diseases, and agricultural vulnerability to climate risks. Finally, we highlight important findings and directions for future research and implementation. The detailed review presented in this paper provides sufficient evidence that the climate in California has changed significantly and is expected to continue changing in the future, and justifies the urgency and importance of enhancing the adaptive capacity of agriculture and reducing vulnerability to climate change. Since agriculture in California is very diverse and each crop responds to climate differently, climate adaptation research should be locally focused along with effective stakeholder engagement and systematic outreach efforts for effective adoption and implementation. The expected readership of this paper includes local stakeholders, researchers, state and national agencies, and international communities interested in learning about climate change and California’s agriculture.

In California, alfalfa is grown on a large area ranging between 325,000 and 410,000 hectares and ranks among the thirstiest crops. While the hay production industry is often scrutinized for the large usage of the state’s agricultural water, alfalfa is a crucial feed-supplier for the livestock and dairy sectors, which rank among the most profitable commodity groups in the state. Sub-surface drip irrigation (SDI), although only practiced on approximately 2% of the alfalfa production area in California, is claimed to have the potential to significantly increase hay yield (HY) and water productivity (WP) compared with surface irrigation (SI). In 2014–2016 we interviewed a number of growers pioneering SDI for alfalfa production in Central and Southern California who reported that yield improvements in the order of 10–30% and water saving of about 20–30% are achievable in SDI-irrigated fields compared with SI, according to their records and perceptions collected over few years of experience. Results from our research on SDI at the University of California, Davis, revealed significantly smaller yield gain (~5%) and a slight increase of water use (~2–3%) that are similar to findings from earlier research studies. We found that most of the interviewed alfalfa producers are generally satisfied with their SDI systems, yet face some challenges that call for additional research and educational efforts. Key limitations of SDI include high investment costs, use of energy to pressurize water, the need for more advanced irrigation management skills, and better understanding of soil-water dynamics by farm personnel. SDI-irrigated fields also need accurate water monitoring and control, attentive prevention and repair of rodent damages, and careful salinity management in the root zone. In this paper we attempt to evaluate the viability of the SDI technology for alfalfa production on the basis of preliminary results of our research and extension activities, with focus on its water and energy footprints within the context of resource efficiency.

— Nutrients, sediment and silt in drainage waters have been identified as the leading cause for water quality impairments in rivers and waterbodies in California. Approximately one-third of applied irrigation water leaves irrigated field as surface runoff and subsurface drainage. In this project, we implemented seven standard and improved irrigation and fertigation management practices on a commercial alfalfa field to reduce the load and concentration of phosphorus and sediment in drainage waters. Reducing the amount of surface runoff after the application of P fertilizer is a key factor in reducing the load of P in drainage waters. The loads of P in runoff waters were reduced by as much as 75% compared to normal irrigation and fertigation practices. Water-run application of P increased the concentration and load of P in runoff water by almost 100% compare to broadcast P applications. Avoiding water-run applications can reduce the load of P in runoff water by more than 50%.

Shallow groundwater contamination by nitrate is frequent in agricultural lands in Egypt because of the use of urea fertilizers. The urea transformation process in the vadose zone was simulated using a HYDRUS-2D model, Software package for simulations of 2D movement of water, heat, and multiple solutes in variably saturated media, for subsurface drip irrigation. The root water and nutrient uptake were assessed for three soil types (sandy loam, loam, and silty loam) with three emitter discharge levels (1.0 L h&minus, 1, 1.50 L h&minus, 1, and 2.0 L h&minus, 1), for a comparison of three fertigation strategies (A) at the beginning, (B) at the end, and (C) at the middle of the irrigation cycle. The extension of the wetted area mainly depends on soil hydraulic conductivity. The high emitter discharge with a short irrigation time is suitable for shallow-rooted crops. The cumulative flux was highest for silty loam soil and the lowest was for the sandy loam soil (1891, and 1824 cm3) for the 2 L h&minus, 1 emitter discharge within the 35 days simulation. The cumulative drainage significantly differs among soil types with little effect of emitter discharge. It recorded 1213, 295, 11.9 cm3 for sandy loam, loam, silty loam, respectively. Urea transformation is controlled by hydrolysis and nitrification as well as the adsorption coefficient of ammonium. Nitrate distribution is mainly governed by soil type rather than the emitter discharge where the sandy loam soil is more highly susceptible to nitrate leaching than to silty loam. Nitrate concentration has recorded the minimum possible level when applying the urea fertilizer at the beginning of the irrigation event for sandy loam and loam soil while for the silty loam soil, urea application at the middle of the irrigation event is more effective. Urea application at the end of the irrigation event gives the highest accumulated leached nitrate concentration below the root zone and should be avoided (the worst strategy).

A method is presented that uses continuous soil moisture measurements and hourly reference evapotranspiration data to estimate a soil hydraulic factor (β) for modeling soil evaporation. The β factor is used to assess the end of the energy limited soil evaporation phase (Stage 1) and the evaporation rate during the soil hydraulic limited phase (Stage 2) of a two-stage soil evaporation model. A previously developed and tested method to determine β uses an energy balance approach with sensible heat flux density estimated using the surface renewal method to obtain the continuous soil evaporation. A new method is presented, which uses a hydroprobe soil moisture measuring device to estimate the continuous soil evaporation. The estimation of evaporation with soil moisture sensors was simpler and less expensive when compared to the energy balance technique. The methods, evaluated in two field experiments, showed good agreement with evaporation data. Using the evaporation model and β derived from either method pro...