Effects of the Structure of Water Rights on Agricultural Production During Drought: A Spatiotemporal Analysis of California\u27s Central Valley

California’s Central Valley region has been called the “bread-basket” of the United States. The region is home to one of the most productive agricultural systems on the planet. Such high levels of agricultural productivity require large amounts of fresh water for irrigation. However, the long-term availability of water required to sustain high levels of agricultural production is being called into question following the latest drought in California. In this paper, we use Bayesian multilevel spatiotemporal modeling techniques to examine the influence of the structure of surface water rights in the Central Valley on agricultural production during the recent drought. California is an important place to study these dynamics as it is the only state to recognize the two dominant approaches to surface water management in the United States: riparian and appropriative rights. In this study, Bayesian spatiotemporal modeling is employed to account for spatial processes that have the potential to influence the effects of water right structures on agricultural production. Results suggest that, after accounting for spatiotemporal dependencies in the data, seniority in surface water access significantly improves crop health and productivity on cultivated lands, but does not independently affect the ability to maintain cultivated extent. In addition, agricultural productivity in watersheds with more junior surface water rights show less sensitivity to cumulative drought exposure than other watersheds, however the extent of cultivation in these same watersheds is relatively more sensitive to cumulative drought exposure

Stacked crop rotations and cultural practices for canola and flax yield and quality

Canola (Brassica napus L.) and flax (Linum usitatissimum L.) are important oilseed crops, but improved management practices to enhance their yields and quality are needed. We studied the effect of stacked versus alternate‐year crop rotations and traditional versus improved cultural practices on canola and flax growth, seed yield, oil concentration, and N‐use efficiency from 2006 to 2011 in the northern Great Plains, USA. Stacked rotations were durum (Triticum turgidum L.)‐durum‐canola‐pea (Pisum sativum L.) (DDCP) and durum‐durum‐flax‐pea (DDFP). Alternate‐year rotations were durum‐canola‐durum‐pea (DCDP) and durum‐flax‐durum‐pea (DFDP). The traditional cultural practice included a combination of conventional tillage, recommended seed rate, broadcast N fertilization, and reduced stubble height. The improved cultural practice included a combination of no‐tillage, increased seed rate, banded N fertilization, and increased stubble height. Canola stand count was 36–123% greater with the improved than the traditional cultural practice in 2006, 2009, 2010, and 2011. Canola pod number and oil concentration were 3–36% greater in the improved than the traditional practice in 2007 and 2010, but trends reversed by 5–19% in 2008. Flax stand count was 28% greater with DFDP than DDFP in 2007 and 56% greater in the improved than the traditional practice in 2010. Flax pod number, seed weight, seed yield, N content, N‐use efficiency, and N‐removal index varied with crop rotations, cultural practices, and years. Canola growth and oil concentration increased with the improved cultural practice as well as flax growth, yield, and quality enhanced with alternate‐year crop rotation and the improved cultural practice in wet years

Transition pathways to sustainable agricultural water management: A review of integrated modeling approaches

Agricultural water management (AWM) is an interdisciplinary concern, cutting across traditional domains such as agronomy, climatology, geology, economics, and sociology. Each of these disciplines has developed numerous process-based and empirical models for AWM. However, models that simulate all major hydrologic, water quality, and crop growth processes in agricultural systems are still lacking. As computers become more powerful, more researchers are choosing to integrate existing models to account for these major processes rather than building new cross-disciplinary models. Model integration carries the hope that, as in a real system, the sum of the model will be greater than the parts. However, models based upon simplified and unrealistic assumptions of physical or empirical processes can generate misleading results which are not useful for informing policy. In this article, we use literature and case studies from the High Plains Aquifer and Southeastern United States regions to elucidate the challenges and opportunities associated with integrated modeling for AWM and recommend conditions in which to use integrated models. Additionally, we examine the potential contributions of integrated modeling to AWM - the actual practice of conserving water while maximizing productivity. Editor's note: This paper is part of the featured series on Optimizing Ogallala Aquifer Water Use to Sustain Food Systems. See the February 2019 issue for the introduction and background to the series.Peer reviewedPlant and Soil Science

Disparities exist between National food group recommendations and the dietary intakes of women

<p>Abstract</p> <p>Background</p> <p>Preconception and pregnancy dietary intakes can influence the health of future generations. In this study we compared the food intakes of reproductive-aged women by pregnancy status, to current Australian recommendations.</p> <p>Methods</p> <p>Data are from the Australian Longitudinal Study on Women's Health, younger cohort aged 25-30 years in 2003, with self-reported status as pregnant (n = 606), trying to conceive (n = 454), given birth in the last 12 months (n = 829) or other (n = 5597). Diet was assessed using a validated 74-item food frequency questionnaire. Food group servings and nutrient intakes were compared to the Australian Guide to Healthy Eating (AGHE) and Australian Nutrient Reference Values (NRVs).</p> <p>Results</p> <p>No women met all AGHE food group recommendations. Highest adherence rates [mean (95% CI) servings/day] were for meat [85%, 1.9(1.8-1.9)], fruit [44%, 2.1(2.1-2.2)] and dairy [35%, 1.8(1.8-1.9)], with < 14% meeting remaining recommendations. Women who achieved NRVs (folate, iron, calcium, zinc, fibre) for pregnancy, breastfeeding and adult life stages were 1.5%, 3.3% and 13.7%, respectively. Compared to AGHE, women consumed more servings of fruit (4.9 vs 4.0;<it>P </it>= 0.034) and dairy (3.4 vs 2.0;<it>P </it>= 0.006) to achieve pregnancy NRVs; more dairy (2.9 vs 2.0;<it>P </it>= 0.001), less fruit (3.9 vs 5.0;<it>P </it>< .001) and vegetables (3.4 vs 7.0;<it>P </it>< .001) to achieve breastfeeding NRVs; more fruit (3.6 vs 3.0;<it>P </it>< .001), dairy (2.5 vs 2.0;<it>P </it>< .001), meat (1.8 vs 1.5;<it>P </it>= 0.015), less vegetables (3.6 vs 5.0;<it>P </it>< .001) to achieve adult NRVs.</p> <p>Conclusions</p> <p>The AGHE does not align with contemporary diets of Australian women or enable them to meet all NRVs. Current tools to guide food consumption by women during pregnancy require revision.</p

Primed acclimation of cultivated peanut (Arachis hypogaea L.) through the use of deficit irrigation timed to crop developmental periods

Water-deficits and high temperatures are the predominant factors limiting peanut production across the U.S., either because of regional aridity or untimely rainfall events during crucial crop developmental periods. In the southern High Plains of west Texas and eastern New Mexico, low average annual rainfall (450. mm) and high evaporative demand necessitates the use of significant irrigation in production systems. In this west Texas study, the primary objective was to develop irrigation schemes that maximized peanut yield and grade while reducing overall water consumption. Therefore, a large-scale field experiment was established in 2005 and 2006 that utilized 15 treatment combinations of differing rates of irrigation (50, 75, and 100% of grower applied irrigation) applied at different periods of peanut development (early, middle, and late season). Precipitation patterns and ambient temperatures showed greater stress levels in 2006 which likely reduced yields across all treatments in comparison to 2005. Yields were reduced 26 (2005) and 10% (2006) in the lowest irrigation treatment (50% full season) compared with full irrigation (100% full season); but early-season water deficit (50 and 75% in the first 45. days after planting) followed by 100% irrigation in the mid- and late-seasons were successful at sustaining yield and/or crop value. Root growth was significantly enhanced at 50% irrigation compared with 100% irrigation, through greater root length, diameter, surface area, and depth, suggesting greater access to water during mid- and late-season periods. These results suggest that early to mid-season deficit irrigation has the potential to maintain peanut yield without altering quality, and to substantially reduce water use in this semi-arid environment

Soil type influences crop mineral composition in Malawi

Food supply and composition data can be combined to estimate micronutrient intakes and deficiency risks among populations. These estimates can be improved by using local crop composition data that can capture environmental influences including soil type. This study aimed to provide spatially resolved crop composition data for Malawi, where information is currently limited. Six hundred and fifty-two plant samples, representing 97 edible food items, were sampled from N150 sites in Malawi between 2011 and 2013. Samples were analysed by ICP-MS for up to 58 elements, including the essential minerals calcium (Ca), copper (Cu), iron (Fe), magnesium (Mg), selenium (Se) and zinc (Zn). Maize grain Ca, Cu, Fe, Mg, Se and Zn concentrations were greater from plants grown on calcareous soils than those from the more widespread low-pH soils. Leafy vegetables from calcareous soils had elevated leaf Ca, Cu, Fe and Se concentrations, but lower Zn concentrations. Several foods were found to accumulate high levels of Se, including the leaves of Moringa, a crop not previously been reported in East African food composition data sets. New estimates of national dietary mineral supplies were obtained for non-calcareous and calcareous soils. High risks of Ca (100%), Se (100%) and Zn (57%) dietary deficiencies are likely on non-calcareous soils. Deficiency risks on calcareous soils are high for Ca (97%), but lower for Se (34%) and Zn (31%). Risks of Cu, Fe and Mg deficiencies appear to be low on the basis of dietary supply levels

Participatory Women's Groups with Cash Transfers Can Increase Dietary Diversity and Micronutrient Adequacy during Pregnancy, whereas Women's Groups with Food Transfers Can Increase Equity in Intrahousehold Energy Allocation.

Background: There is scarce evidence on the impacts of food transfers, cash transfers, or women's groups on food sharing, dietary intakes, or nutrition during pregnancy, when nutritional needs are elevated. Objective: This study measured the effects of 3 pregnancy-focused nutrition interventions on intrahousehold food allocation, dietary adequacy, and maternal nutritional status in Nepal. Methods: Interventions tested in a cluster-randomized controlled trial (ISRCTN 75964374) were "Participatory Learning and Action" (PLA) monthly women's groups, PLA with transfers of 10 kg fortified flour ("Super Cereal"), and PLA plus transfers of 750 Nepalese rupees (∼US$7.5) to pregnant women. Control clusters received usual government services. Primary outcomes were Relative Dietary Energy Adequacy Ratios (RDEARs) between pregnant women and male household heads and pregnant women and their mothers-in-law. Diets were measured by repeated 24-h dietary recalls. Results: Relative to control, RDEARs between pregnant women and their mothers-in-law were 12% higher in the PLA plus food arm (log-RDEAR coefficient = 0.12; 95% CI: 0.02, 0.21; P = 0.014), but 10% lower in the PLA-only arm between pregnant women and male household heads (-0.11; 95% CI: -0.19, -0.02; P = 0.020). In all interventions, pregnant women's energy intakes did not improve, but odds of pregnant women consuming iron-folate supplements were 2.5-4.6 times higher, odds of pregnant women consuming more animal-source foods than the household head were 1.7-2.4 times higher, and midupper arm circumference was higher relative to control. Dietary diversity was 0.4 food groups higher in the PLA plus cash arm than in the control arm. Conclusions: All interventions improved maternal diets and nutritional status in pregnancy. PLA women's groups with food transfers increased equity in energy allocation, whereas PLA with cash improved dietary diversity. PLA alone improved diets, but effects were mixed. Scale-up of these interventions in marginalized populations is a policy option, but researchers should find ways to increase adherence to interventions. This trial was registered at www.controlled-trials.com as ISRCTN 75964374