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Information on actual consumptive water use and water productivity of wine grape vineyards grown with high-wire cordon (HWC) and vertical shoot position (VSP) trellis systems is limited, but it is critical to inform the selection of resource-efficient grapevine training systems and irrigation water management practices. This article describes an applied-research study conducted in the Central Valley of Chile to determine the actual evapotranspiration (ETa), actual crop coefficients (Ka), water productivity (WP), and water footprint (WFP) of microirrigated wine grape vineyards operated for commercial production with HWC and VSP trellis systems. ETa and Ka were determined using the residual of the energy balance (REB) method from micrometeorological measurements collected at the study vineyards with a combination of surface renewal and eddy covariance equipment. Field measurements of other biophysical parameters were also collected at each study site to characterize the soil water status in multiple locations across the vineyards at various soil depths using moisture tension–monitoring units, vine water status using midday stem water potential (ΨSTEM) , and fraction of photosynthetically active radiation (fPAR) intercepted by the vine canopy at different times during the growing season. Finally, the fruit yield was determined from grape samples collected at the HWC and VSP vineyard blocks during commercial harvest operations. The study was conducted over the course of two consecutive growing seasons (2019–2020 and 2020–2021). A reduction of 37% in the available water supply occurred during the 2019–2020 season with respect to the average water supply. Findings from the research study showed that when the water supply was less limited, the HWC trellis had 12% higher seasonal cumulative ETa than the VSP trellis, whereas the HWC system appeared more affected by water stress than the VSP trellis during the water-limited season. The analysis of the data sets also showed that the HWC enabled wine grape growers to achieve significantly higher fruit yield and water productivity, and lower water footprint per unit of wine grapes produced during the water-limited season. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Proximal sensing is being integrated into vineyard management as it provides rapid assessments of spatial variability of soils' and plants' features. The electromagnetic induction (EMI) technology is used to measure soil apparent electrical conductivity (ECa) with proximal sensing and enables to appraise soil characteristics and their possible effects on plant physiological responses. This study was conducted in a micro irrigated Cabernet Sauvignon (Vitis vinifera L.) vineyard to investigate the technical feasibility of appraising plant water status and its spatial variability using soil ECa and must carbon isotope ratio analysis (δ13C). Soil temperature and soil water content were monitored in-situ using time domain reflectometry (TDR) sensors. Soil ECa was measured with EMI at two depths [0–1.5 m (deep ECa) and 0–0.75 m (shallow ECa)] over the course of the crop season to capture the temporal dynamics and changes. At the study site, the main physical and chemical soil characteristics, i.e. soil texture, gravel, pore water electrical conductivity (ECe), organic carbon, and soil water content at field capacity, were determined from samples collected auguring the soil at equidistant points that were identified using a regular grid. Midday stem water potential (Ψstem) and leaf gas exchange, including stomatal conductance (gs), net carbon assimilation (An), and intrinsic water use efficiency (WUEi) were measured periodically in the vineyard. The δ13C of produced musts was measured at harvest. The results indicated that soil water content (relative importance = 24%) and texture (silt: relative importance = 22.4% and clay: relative importance = 18.2%) were contributing the most towards soil ECa. Deep soil ECa was directly related to Ψstem (r2 = 0.7214) and gs (r2 = 0.5007). Likewise, δ13C of must was directly related to Ψstem (r2 = 0.9127), gs (r2 = 0.6985), and An (r2 = 0.5693). Results from this work provided relevant information on the possibility of using spatial soil ECa sensing and δ13C analysis to infer plant water status and leaf gas exchange in micro irrigated vineyards. [ABSTRACT FROM AUTHOR]

This article presents findings from a field research study conducted in the San Joaquin Valley of California in 2016–2018 to appraise the effects of soil salinity and sodicity on evapotranspiration and energy balance components of micro-irrigated pistachio orchards. Actual evapotranspiration (ETa) and tree physiologic parameters were measured during consecutive growing seasons in mature orchards grown on non-saline and saline/sodic soils. Salinity and sodicity decreased pistachio water use by about 30%, with ETa reductions varying along the growing season. Accurate information on the dynamics of ETa and energy balance components along the growing season can improve water management for nut orchards exposed to long-term saline-sodic conditions. Results show that the main driver of ETa was the net radiation (Rn), which supplied most of the energy to vaporize water, irrespective of the growth period and level of salinity/sodicity. Field observations revealed that Rn was lower for salt-affected trees due to smaller canopies, which intercepted less light than non-saline trees. Secondarily, the exchange of sensible heat (H) between the ambient air and tree canopies was affected by the interaction between salinity–sodicity and seasonality. Early in the season, salinity and sodicity affected ETa mainly through the reduced canopy growth, which decreased the available energy (Rn–G) for ETa and reduced the water uptake as a result of the lower soil water potential. Late in the season, an increase in H and a decrease in the contribution of the aerodynamic component (β coefficient) to the latent heat flux (LE) occurred, which determined a further reduction of ETa due to a physiological response. The decrease in the β coefficient during the late season was associated with a direct impact of ion accumulation on leaf functionality. Collecting data on the contribution of the aerodynamic component to LE offers a low-cost method to detect and quantify physiological stress, while providing useful information for managing irrigation in salt-affected orchards. The results presented in this article provide insights to improve irrigation management of salt-affected pistachio through integration of weather measurements, energy balance components, and plant-based parameters. [ABSTRACT FROM AUTHOR]

Background: Preventing dementia onset is one of the global public health priorities: around 35% of dementia cases could be attributable to modifiable risk factors. These estimates relied on secondary data and did not consider the concurrent effect of non-modifiable factors and death. Here, we aimed to estimate the potential reduction of dementia incidence due to modifiable risk factors elimination, controlling for non-modifiable risk factors and for the competing risk of death. Methods: Participants from the InveCe.Ab population-based prospective cohort (Abbiategrasso, Italy) without a baseline dementia diagnosis and attending at least one follow-up visit were included (N = 1100). Participants underwent multidimensional assessment at baseline and after 2, 4, and 8 years, from November 2009 to January 2019. Modifiable risk factors were low education, obesity, hypertension, diabetes, depression, smoking, physical inactivity, hearing loss, loneliness, heart disease, stroke, head injury, and delirium. Non-modifiable risk factors were age, sex, and APOE ε4 genotype. The primary endpoint was dementia diagnosis within the follow-up period (DSM-IV criteria). We performed competing risk regression models to obtain sub-hazard ratio (SHR) for each exposure, with death as competing risk. The exposures associated with dementia were included in a multivariable model to estimate their independent influence on dementia and the corresponding population attributable fraction (PAF). Results: Within the study period (mean follow-up, 82.3 months), 111 participants developed dementia (10.1%). In the multivariable model, APOE ε4 (SHR = 1.89, 95% CI 1.22–2.92, p = 0.005), diabetes (SHR = 1.56, 95% CI 1.00–2.39, p = 0.043), heart disease (SHR = 1.56, 95% CI 1.03–2.36, p = 0.037), stroke (SHR = 2.31, 95% CI 1.35–3.95, p = 0.002), and delirium (SHR = 8.70, 95% CI 3.26–23.24, p < 0.001) were independently associated with increased dementia risk. In the present cohort, around 40% of dementia cases could be attributable to preventable comorbid diseases. Conclusions: APOE ε4, diabetes, heart disease, stroke, and delirium independently increased the risk of late-life dementia, controlling for the competing risk of death. Preventive intervention addressed to these clinical populations could be an effective approach to reduce dementia incidence. Further studies on different population-based cohort are needed to obtain more generalizable findings of the potential of dementia prevention in the real-world setting. Trial registration: ClinicalTrials.gov, NCT01345110. [ABSTRACT FROM AUTHOR]

Objective: Hearing loss is a common chronic condition in elderly people. The prevalence of disabling hearing loss among the elderly worldwide is 33% and in Italy ranges from 0.6% (profound hearing loss) to 39% (mild hearing loss). We investigated the relationship between self-reported hearing disability and clinician-evaluated hearing status, and its longitudinal consequences in relation to cognitive impairment and functional decline. We hypothesised that subjects who report that they have a hearing disability have a worse functional and cognitive profile than people who do not report having a hearing disability.Methods: We analysed 1171 participants in the InveCe.Ab study, a longitudinal population-based study. We evaluated whether self-reported hearing disability was consistent with clinician-evaluated hearing status (using the Whispered Voice Test; WVT), categorizing this variable as: unaware of hearing loss (UHL), aware of hearing loss (AHL), only subjective hearing loss (OSHL), without hearing loss (noHL). We also examined its relationship with various population characteristics, and its long-term effects on functional and cognitive performance and depressive symptoms.Results: At baseline, hearing loss was found in 13.6% (95% CI: 11.7-15.7) of the participants [17.6% (95% CI: 12.0-24.4) AHL; 82.4% (95% CI: 75.6-88) UHL], while 2.3% (95% CI: 1.4-3.4) of the subjects with normal WVT hearing status had OSHL. Male gender, age, functional and cognitive performance, and depressive symptoms were associated with consistency between self-reported hearing disability and WVT hearing status. Longitudinal analysis revealed worsening functional performance and selective attention, global cognitive deterioration, and depressive symptoms in the AHL group.Conclusions: Our results showed that awareness of hearing disability in the elderly has adverse cognitive and functional consequences over time. When clinicians inform those who are unaware of their hearing problems, they should arrange for prompt referral not only for audiometric evaluation but also for counselling in order to prevent a negative impact of awareness of hearing loss. [ABSTRACT FROM AUTHOR]

This paper investigates the association between work trajectories and frailty in later life in four ageing contexts (AAI index): Czech Republic, Denmark, Italy and Poland. Data of the Survey of Health, Ageing and Retirement in Europe (SHARE) is used to create the frailty index and linear regression models are applied to assess the association between frailty condition and work trajectories of 6187 women and men, aged between 50 and 74 years old. The findings underline that women experience worse frailty than men in all countries. Having precarious work trajectories is detrimental to individuals' health everywhere, but it becomes even worse for Danish men and Polish men and women. The ageing context (AAI index) is not associated with health inequalities in older people. We suggest that further research should explore more in detail the mechanisms linking job insecurity to psycho-social risks as possible determinants of frailty, taking into account differences at the national level. [ABSTRACT FROM AUTHOR]

Innovative irrigation practices can enhance water efficiency, gaining an economic advantage while also reducing environmental burdens. In some cases the necessary knowledge has been provided by extension services, helping farmers to adapt and implement viable solutions, thus gaining more benefits from irrigation technology. Often investment in technological improvements has incurred higher water prices, however, without gaining the full potential benefits through water efficiency. Farmers generally lack adequate means and incentives to know crops’ water use, actual irrigation applications, crops’ yield response to different water management practices, and thus current on-farm water-efficiency levels. Those general difficulties are illustrated by our two case studies investigating options, stimuli and difficulties to improve water-efficient practices. The two areas have strong stimuli for improvement but lack a knowledge-exchange system to help farmers and resource managers identify scope for improvements. Partly for this reason, farmers’ responsibility for efficient water management has been displaced to hypothetical prospects, e.g. extra supplies from reuse of treated wastewater or a long-term low water pricing. In both cases a displaced responsibility complements the default assumption that farmers’ irrigation practices already have adequate water-use efficiency. Under current circumstances, agricultural water management will maintain the unknown water-efficiency level and farmers will have weaker incentives to make efforts for more efficient practices. A continuous knowledge-exchange is necessary so that all relevant stakeholders can share greater responsibility across the entire water-supply chain. On this basis, more water-efficient management could combine wider environmental benefits with economic advantage for farmers. [ABSTRACT FROM AUTHOR]

A methodology to assess performance of pressurized irrigation distribution networks is presented, which is based on generation of flow configurations from simulated delivery scenarios, and on subsequent analysis of network operation and delivery achievements. The rationale of the methodology entails simulating the peak-demand flow configurations in the pipe network through a deterministic-stochastic combined agro-hydrological model, and forecasting the delivery performance by means of a hydraulic simulation model and of some specific performance indicators. The agro-hydrological model generates disaggregated information on soil water deficits for all the cropped fields downstream from the delivery hydrants, and forecasts the demand flow hydrographs and irrigation deliveries for the entire service area during peak-demand periods. The simulated-demand flow configurations are then passed on to the hydraulic simulation model, which evaluates the hydraulic performance achievable by the pipe network. The performance analysis is then refined using additional indicators specifically adapted to pressurized irrigation networks. The proposed methodology was applied to a large-scale pressurized irrigation system of southern Italy that is in need of modernization. Results proved the usefulness of the combined use of simulation tools as components of an analytical framework to address modernization and re-engineering of existing irrigation delivery networks, on the basis of targeted delivery performance. [ABSTRACT FROM AUTHOR]

A deterministic-stochastic combined model named HydroGEN was developed, as described in a companion paper (Part I: Model development), to enable the simulation of demanded daily volumes and hourly flow rates during peak periods in pressurized irrigation delivery networks. The model was applied to a pilot large-scale irrigation system located in southern Italy for calibration and for testing its reliability in analyzing the operation of large-scale pressurized delivery systems through the simulated flow configurations. Daily input data on rainfall, temperature, solar radiation, wind speed and relative humidity were gathered from a meteorological station located within the study area, whereas information on local irrigation management practices were collected through interviews with farmers and from extension specialists. The model was tested at different management levels, from district to sector and hydrants. The model testing was supported by the use of high-resolution remote-sensing imagery acquired on a single overpass date in 2006 and then classified and recoded following a ground-truthing campaign conducted during the same year. Simulations were performed to identify the 10-day peak-demand period and to generate the hydrographs of daily volumes and of hourly flow rates. Results from the different simulations were compared with historical datasets of irrigation volumes and discharges recorded during the 2008 and 2009 seasons at the upstream end of the irrigation network under study, at a sector level during the 2007 season and at selected delivery hydrants during the 2005 season. Some discrepancies between simulated and recorded data were noted that can be related to small errors in estimating crop and soil parameters, application efficiency at field level, as well as to large variability in irrigation management practices followed by local farmers. Overall, the results from testing showed that the model is capable of forecasting with good accuracy the timing of peak-demand periods, the irrigation volumes demanded during the season, as well as the hydrographs of daily volumes and hourly flow rates withdrawn by farmers during these peak-demand periods, especially when it is applied to large multi-cropped command areas. [ABSTRACT FROM AUTHOR]

This study describes a model named HydroGEN that was conceived for simulating hydrographs of daily volumes and hourly flow rates during peak-demand periods in pressurized irrigation delivery networks with on-demand operation. The model is based on a methodology consisting of deterministic and stochastic components and is composed of a set of input parameters to reproduce the crop irrigation management practices followed by farmers and of computational procedures enabling to simulate the soil water balance and the irrigation events for all cropped fields supplied by each delivery hydrant in a distribution network. The input data include values of weather, crop, and soil parameters, as well as information on irrigation practices followed by local farmers. The resulting model outputs are generated flow hydrographs during the peak-demand period, which allow the subsequent analysis of performance achievable under different delivery scenarios. The model can be applied either for system design or re-design, as well as for analysis of operation and evaluation of performance achievements of on-demand pressurized irrigation delivery networks. Results from application of HydroGEN to a real pressurized irrigation system at different scales are presented in a companion paper (Part II: model applications). [ABSTRACT FROM AUTHOR]

This study was conducted on an irrigated area of southern Italy to analyze the current operation of a large-scale irrigation delivery system and the effects of the operation procedures on crop irrigation management and aquifer salinity increase. The area is characterized by relatively high levels of groundwater salinity in the summer that are probably due to intensive groundwater pumping by farmers during periods of peak irrigation demand, with the resulting seawater intrusion. Two alternative delivery schedules, namely the rotation delivery schedule and the flexible delivery schedule, referred to as RDS and FDS, respectively, were simulated using a soil-water balance model under different combinations of crop, soil and climatic conditions. The first set of simulations concerned the farm irrigation management constrained by the rotational delivery used by the local water management organization. The second scenario simulated the farm irrigation schedule most commonly used by growers in the area for maximizing crop yields. Based on crop irrigation management under RDS and FDS, two alternative operational scenarios were also developed at the scheme level and then compared for evaluation. Winter and summer salinity maps of the aquifer were developed by interpolating salinity measurements of the groundwater samples collected during the 2006 irrigation season. From these maps, a close relationship can be inferred among delivery schedule, aquifer exploitation and salinity increase, which justifies the need for implementing FDS that might reduce the groundwater demand for irrigation. [ABSTRACT FROM AUTHOR]

The article deals with the need for sustainable management of water resources in line with the problem of global warming. An overview of how electrical energy can lead to improved management of annually renewable water is presented. The benefits from better management of renewable water resources such as precipitation, groundwater and streamflow are discussed. A comparison of the potential of hydropower and wind power is outlined.

There is an urgent need to understand the consequences of the Covid-19 pandemics on older people's lives. However, conducting qualitative research is challenging, because of the shortage of guidelines and methodological research on how to recruit and interview participants during biological disasters, such as pandemics. This paper documents the procedures we adopted to recruit and interview 40 older people living in a rural area of Northern Italy that was subject to the first full lockdown in Europe. Despite the challenges arising when qualitatively researching the old age population in pandemic times, our study has shown that it is feasible to recruit and interview older people remotely. Specifically, community engagement and tailoring video-interviews according to older people's needs and ICT skills are the key aspects to consider when designing these types of studies. [ABSTRACT FROM AUTHOR]

California farmers who use reduced-disturbance tillage and winter cover cropping can boost production and improve soil health. However, some farmers are hesitant to try these conservation practices due to uncertainty about whether planting winter cover crops will deplete soil moisture in already drought-stricken regions. Our study addresses these concerns by looking at how long-term reduced-disturbance tillage and winter cover cropping, compared to fallowed soils with standard tillage, affected soil moisture. Although we found a statistical difference in total soil water content, the difference was only about 0.3 inches of water per foot of soil. On average, the soil water content of the top 0-96 inches was highest for the reduced-disturbance fields with winter cover crops. This was especially evident during our driest field season, from November 1, 2017, to March 15, 2018, when cumulative rainfall was only 1.9 inches. Our findings show that winter cover cropping and reduced-disturbance tillage can improve soil without depleting soil water levels in row crops. [ABSTRACT FROM AUTHOR]

To meet the requirements of California’s Sustainable Groundwater Management Act, there is a critical need for crop production strategies with less reliance on irrigation from surface and groundwater sources. One strategy for improving agricultural water use efficiency is reducing tillage and maintaining residues on the soil surface. We evaluated high residue no-till versus standard tillage in the San Joaquin Valley with and without cover crops on the yields of two crops, garbanzo and sorghum, for 4 years. The no-till treatment had no primary or secondary tillage. Sorghum yields were similar in no-till and standard tillage systems while no-till garbanzo yields matched or exceeded those of standard tillage, depending on the year. Cover crops had no effect on crop yields. Soil cover was highest under the no-till with cover crop system, averaging 97% versus 5% for the standard tillage without cover crop system. Our results suggest that garbanzos and sorghum can be grown under no-till practices in the San Joaquin Valley without loss of yield. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Background: Doll therapy is a non-pharmacological intervention for people with dementia aimed to reduce distressing behaviours. Reliable results on the efficacy of Doll therapy for people with dementia are needed. The concept of attachment theorised by Bowlby has been proposed to explain the Doll therapy process, but it has not been proven to influence the response to doll presentation.Methods/design: This single-blind, randomised controlled trial will involve people with dementia living in nursing homes of the Canton Ticino (Switzerland). Participants will be randomised to one of two interventions: Doll Therapy Intervention or Sham Intervention with a non-anthropomorphic object, using a 1:1 allocation ratio. The two interventions will consist of 30 daily sessions lasting an hour at most, led by a trained nurse for an hour at most. We will enrol 64 participants per group, according to power analysis using an estimated medium effect size (f = 0.25), an alpha level of 0.05, and a power of 0.8. The primary goal is to test the efficacy of the Doll Therapy Intervention versus the Sham Intervention as the net change in the following measures from baseline to 30 days (blinded outcomes): the Neuropsychiatric Inventory-Nursing Home administered by a trained psychologist blinded to group assignment, the professional caregivers' perceived stress scale of the Neuropsychiatric Inventory-Nursing Home, patients' physiological indices of stress (salivary cortisol, blood pressure and heart rate) and interactive behaviours. The secondary goal is to assess the relationship between attachment styles of people with dementia (detected by means of the Adult Attachment Interview to the patients' offspring) and their caregiving behaviours shown during the Doll Therapy Intervention.Discussion: This is the first single-blind, randomised controlled trial on the efficacy of Doll therapy for dementia and an explanatory model of the response of people with dementia to doll presentation.Trial Registration: ClinicalTrials.gov, ID: NCT03224143. Retrospectively registered on 21 July 2017. [ABSTRACT FROM AUTHOR]

The uncertainty of water resources availability is a growing problem in California as agricultural industrialization, population growth, and climate change affect water resources. The intense manipulation of the hydrological regime has led to the depletion of the water resources in the state and the subsequent use of various adaptive management strategies to cope with environmental conditions and social concerns. The historical imbalance between water pumping and replenishment in Pajaro Valley has led to overdrafted aquifers, seawater intrusion, and salinization. The objective of this study is to estimate the sustainable carrying capacity of agricultural land in Pajaro Valley while preventing groundwater overdraft. A groundwater box model was built and calibrated using historical data to represent current and future hydrology and water management strategies. An optimization model maximized the economic profit using the agricultural acreage as the decision variable with a set of constraints aimed at determining the sustainable carrying capacity of the groundwater basin. Model constraints include total land and water availability, crop acreage, agricultural water use, and historical demand. In the Pajaro Valley, agricultural operations must use less water more efficiently, which means changes in crop types, size of activities, and fallowing land in parts of the basin. Results of the optimal scenario over 25 years show a 15% reduction of total agricultural acreage, 8.5% reduction in food production, average profit loss of 4%, and a 79% reduction in aquifer depletion. This study provides an overall vision of what can be accomplished with coordinated land use planning using strategies that harmonize individual decisions and shared natural resources. [ABSTRACT FROM AUTHOR]

• A user-friendly simulator for estimating tree PAR interception under different latitudes, canopy dimensions, leaf densities, tree spacing, and row orientations. • Predicting the solar radiation interception by mechanically pruned citrus trees. • PAR interception by citrus trees based on the canopy geometry and its shading patterns. • To inform irrigation planning and management decisions for different site-specific conditions. Diurnal and seasonal patterns of photosynthetically active radiation (PAR) intercepted by tree canopies in production orchards have an important role for eco-physiological processes that determine tree water use and productivity. Under well-watered conditions, PAR intercepted by trees is a reliable predictor of crop consumptive water use, which is regulated by tree spacing, tree row orientation, and by the tree canopy dimensions and geometry. Despite its advantages, only rare attempts have been made by the scientific and fruit production communities to develop canopy PAR interception simulators that rely on analytical principles to inform irrigation planning and management decisions. In this article, a novel model is presented that simulates PAR interception by citrus trees based on the canopy geometry and its shading patterns. The article also illustrates preliminary field testing and validation of the model with data collected in commercial citrus production orchards located in the San Joaquin Valley of California. The testing and validation could enable citrus growers and orchard managers to predict the net radiation for mature, micro-irrigated Navel orange and Page mandarin orchards grown with north–south and east–west tree row orientations and different tree densities. Results from the simulations and field validation showed that the canopy PAR light interception contributed 58.8 (± 0.02) and 71.1 (± 1.60) percent to the overall net radiation for the Navel orange orchards during the periods around summer solstice and autumnal equinox, respectively, whereas for the Page mandarin orchards, PAR light interception contributed 63.0 (± 5.60) and 85.7 (± 18.87) percent to the overall net radiation during the same time periods. Good correlations were found between daily values of PAR and net radiation for these citrus production orchards grown with the two alternative row orientations, which suggest that the proposed model could be used to inform irrigation planning and management decisions for different site-specific citrus orchard features and growing conditions. [ABSTRACT FROM AUTHOR]

Recent prolonged droughts in California have emphasized the urgent need to implement more efficient water management practices for high value tree crops. Accurate estimation of evapotranspiration (ET), a main component of consumptive water use, is critical for improving management of micro-irrigated pistachio orchards grown in the San Joaquin Valley of California. We estimated ET of three mature commercial pistachio orchards on non-saline and increasingly saline soils in 2015 and 2016, using the Mapping Evapotranspiration at high Resolution with Internalized Calibration (METRIC) method and Landsat 8 satellite observations. Based on a comparison with field observations at 8 sites, we modified the parameterizations of the momentum roughness length and net radiation for pistachio tree crops and reduced the uncertainty of daily ET estimates. When compared with field data, the recalibrated METRIC ET estimates had an R 2 of 0.59, a mean absolute error of 1.1 mm/day, and a RMSE of 1.4 mm/day during Landsat overpass dates (n = 72). The METRIC ET map captured the temporal dynamics and spatial heterogeneity both within and among the orchards. The mean annual crop season estimated ET (mid-March to mid-October in 2016) with remote sensing decreased by 32% from 1064 ± 99 mm in the non-salt affected control orchard to 725 ± 82 mm in the orchard with the highest level of soil-water salinity. The ET reduction was consistent with canopy volume differences among the study orchards, as shown by summer Normalized Difference Vegetation Index (NDVI) from Landsat observations, e.g., 0.72 ± 0.06 in the control vs. 0.52 ± 0.06 in the most saline orchard. The available energy was controlled mostly by canopy features and explained 64% of daily ET variation among all Landsat pixels and satellite overpass days. The normalized differenced water index (NDWI) could be considered as an important parameter to capture the partitioning of available energy for ET (R 2  = 0.38), suggesting that the lower soil osmotic potential in saline orchards further reduced crop ET. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

California growers face challenges with water shortages and there is a strong need to use the least amount of water while optimizing yield. Timely information on evapotranspiration (ET), a dominant component of crop consumptive water use, is critical for growers to tailor irrigation management based on in-field spatial variability and in-season variations. We evaluated the performance of a remote sensing-based approach, Mapping Evapotranspiration at high Resolution with Internalized Calibration (METRIC), in mapping ET over an almond orchard in California, driven by Landsat satellite observations. Reference ET from a network of weather stations over well-watered grass (ETo) was used for the internal calibration and for deriving ET at daily and extended time period, instead of alfalfa based reference evapotranspiration (ETr). Our study showed that METRIC daily ET estimates during Landsat overpass dates agreed well with the field measurements. During 2009–2012, a root mean square error (RMSE) of 0.53 mm/day and a coefficient of determination (R2) of 0.87 were found between METRIC versus observed daily ET. Monthly ET estimates had a higher accuracy, with a RMSE of 12.08 mm/month, a R2 of 0.90, and a relatively small relative mean difference (RMD) of 9.68% during 2009–2012 growing seasons. Net radiation and Normalized Difference Vegetation Index (NDVI) from remote sensing observations were highly correlated with spatial and temporal ET estimates. An empirical model was developed to estimate daily ET using NDVI, net radiation (Rn), and vapor pressure deficit (VPD). The validation showed that the accuracy of this easy-to-use empirical method was slightly lower than that of METRIC but still reasonable, with a RMSE of 0.71 mm/day when compared to ground measurements. The remote sensing based ET estimate will support a variety of State and local interests in water use and irrigation management, for both planning and regulatory/compliance purposes, and it provides the farmers observation-based guidance for site-specific and time-sensitive irrigation management [ABSTRACT FROM AUTHOR]

Winter cover crops could contribute to more sustainable agricultural production and increase resiliency to climate change; however, their adoption remains low in California. This paper seeks to understand barriers to winter cover crop adoption by monetizing their long-term economic and agronomic impacts on farm profitability in two of California's specialty crop systems: processing tomatoes and almonds. Our modeling effort provides a present, discounted valuation of the long-term use of winter cover crops through a cost-benefit analysis. A net present value model estimates the cumulative economic value of this practice. We then explore how the long-term trade-offs associated with winter cover crops can affect an operation's profits under a spectrum of hypothetical changes in California's agricultural landscape. Our analysis sheds light on the barriers to adoption by reporting benefit-cost ratios that indicate profitability across several scenarios; however, benefits and costs accrue differently over time and with long planning horizons. At the same time, a small portion of gained benefits are external to the grower. Findings from this study reveal that winter cover crops in California can be profitable in the long-term, but the extent of profit depends on the cropping system, extent of irrigation savings due to improved soil function, access to financial subsidies and climate change. Winter cover crops can return positive net benefits to growers who have flexible contractual obligations, can wait for the long-term return on investment and manage cover crops as closely as cash crops. This analysis contributes to the study of conservation agriculture practices by explaining possible reasons for low adoption through an economic valuation of the implications of soil management choices and policy counterfactuals. • Net present value models were used to understand winter cover crop adoption in California. • Winter cover cropping can increase baseline profits in specialty crop systems sometimes. • The value of winter cover crops accrues over many planting seasons. • Reduced irrigation and increased subsidies can increase adoption of cover crops. [ABSTRACT FROM AUTHOR]

• Bioclimatic indices can represent behavior of climatic features over space and time. • Bioclimatic information help identify trends and magnitude of bio-physical changes. • Spatio-temporal bioclimatic information revealed some increasing aridity for Apulia. • Use of the De Martonne index showed spatial and temporal patterns of aridity in Apulia. • Knowledge of bioclimatic features can inform resource planning and management policies. Bioclimatic indices combine atmospheric parameters to provide analytical indication of climatic features and their evolution in space and time that can directly relate with natural resource availability, distribution, and related bio-physical processes. The availability of bioclimatic information can provide natural resource managers with analytical means to assess the magnitude and temporal evolution of drought and climate change parameters that could affect the availability, demand and use of natural resources for various sectors. This paper presents a methodology to process bioclimatic data in the space and time domains for assessing the moisture/dryness level and water requirements of a region, and inform water resource planning and management decisions related to drought, climate variability and change. The methodology relies on a modular assembly of statistical tests and methods, and utilizes point scale measurements of meteorological data to perform the analysis of the spatial behavior of derived bioclimatic indicators at the continuous regional scale, and evaluate the significance of the temporal trends. Also, the article presents an application of the proposed methodology to a coastal area of southern Italy (the Apulia Region) that is characterized by recurring water supply limitations, involving the use of the popular De Martonne bioclimatic aridity index. The methodology allowed to obtain qualitative and quantitative information about the aridity level of the Apulia region, the identification of main bioclimatic zones, and the evaluation of spatial pattern and time evolution of aridity. The determination of bioclimatic zones showed that nearly 40% of the regional territory is characterized by dry sub-humid (Mediterranean) climate, about 30% by sub-humid climate, while nearly 10% and 20% are characterized by semi-arid and humid climates, respectively. The temporal analysis revealed that the Salento and the Ionian coastal zone are areas at risk of increasing aridity, with resulting impacts on the water supply and demand for irrigated agriculture. [ABSTRACT FROM AUTHOR]