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Objective: To support school foods programs by evaluating the relationship between nutritional quality, cost, student consumption, and the environmental impacts of menus. Design: Using linear programing and data from previously served menu items, the relationships between the nutritional quality, cost, student consumption, and the environmental impacts of lunch menus were investigated. Optimized lunch menus with the maximum potential student consumption and nutritional quality and lowest costs and environmental impacts were developed and compared to previously served menus (baseline). Setting: Boston Public Schools, Boston Massachusetts, United States of America. Participants: Menu items served on the 2018-2019 Boston Public School lunch menu (n=142). Results: Using single-objective models, tradeoffs were observed between most interests, but the use of multi-objective models minimized these tradeoffs. Compared to the current weekly menus offered, multi-objective models increased potential caloric intake by up to 27% and healthy eating index scores by up to 19%, and reduced costs and environmental impacts by up to 13% and 71%, respectively. Improvements were made by reducing the frequency of beef and cheese entrées and increasing the frequency of fish and legume entrées on weekly menus. Conclusions: This work can be extrapolated to monthly menus to provide further direction for school districts, and the methods can be employed with different recipes and constraints. Future research should test the implementation of optimized menus in schools and consider the broader implications of implementation.

Although research has demonstrated the positive nutritional value and environmental benefits associated with edible insect consumption, several factors challenge the growth and development of the edible insect industry for human consumption in the US and Canada. Cultural and psychological factors account for much of the aversion US and Canadian consumers display. The absence of specific regulation also constitutes a structural barrier to more widespread production and sale of edible insects. Compared to the US, the European Union has a more developed edible insect industry and has enacted legislation that removes some of the barriers. As consumer awareness of the putative health benefits of edible insects increases, more comprehensive regulations may emerge to keep pace with the growth of this industry. Overall, a multi-disciplinary approach that addresses both benefits and barriers to consumption is needed to facilitate a robust market for edible insects in the US and Canada.

Altering dietary patterns is essential to ameliorating the environmental impacts of the world food system. The U.S. National School Lunch Program shapes the consumption of America’s children and adolescents, providing a meaningful opportunity to reduce dietary environmental impacts. Here, we collate life cycle inventories relevant to the National School Lunch Program and assess the environmental impacts of a representative sample of lunches served in the U.S. during the 2014–2015 school year to inform school meal policy. The mean ± SE impact per lunch was 1.5 ± 0.03 kg CO2 eq. climate change, 1.8 ± 0.03 m2a crop eq. land use, 0.055 ± 0.00 m3 water consumption, and 0.24 ± 0.05 g phosphorus eq. freshwater and 3.1 ± 0.00 g nitrogen eq. marine eutrophication. Meat products contributed the most (28–67%) to total impacts for all impact categories. Lunches in the top quintile of impacts contributed an outsized proportion to total impacts (~40%) suggesting that policy changes related to these lunches should be prioritized. To reduce the environmental impacts of the National School Lunch Program, our results support increasing whole grain requirements and providing serving size or frequency limits for beef.

This study evaluated the nutritional, economic, and environmental impacts of a Meatless Monday (MM) National School Lunch Program (NSLP) in a large urban US school district. After averaging the nut...

Understanding environmental impacts on crop growth and quality is essential in developing sustainable agricultural practices with climate change. Shifts are expected in precipitation, an essential ...

Objective:Navajo Nation residents experience extreme rates of poverty, food insecurity and diet-related diseases. While many residents travel far to shop at grocery stores, there are small stores closer to home that could provide more healthy options, like fruits and vegetables (F&V). Little is known from the perspective of store owners and managers regarding the barriers and facilitators to offering F&V; the present study contributes to filling that gap.Design:Data were collected through structured interviews from a sampling frame of all store owners or managers in the setting (n 29).Setting:Small stores in Navajo Nation, New Mexico, USA. Navajo Nation is predominantly rural and the largest federally recognized Native American tribe in the USA.Participants:Sixteen managers and six owners at twenty-two stores.Results:When asked about the types of foods that were most commonly purchased at their stores, most participants reported snacks and drinks (82 and 68 %, respectively). Many participants reported they would like to offer more fresh F&V. However, barriers included varying perceived customer demand, limited F&V choices from distributors and (for some managers) limited authority over product selection.Conclusions:Findings contribute to the discussion on engaging store owners and managers in providing quality, healthy foods close to home in low-income, rural regions.

What is the role of Northeastern agricultural products in the US food system? This paper presents a typology that categorizes where agricultural production and distribution of a specific geographic area, in this case a multi-state region, fits within the US food system. The place of each food is defined based on its production volume, scope of distribution, market timing and agro-ecological niche. Six distinct roles that a region might play in supplying food are identified: (a) the region is a national production center, (b) the region is a seasonally important supplier, (c) regional production and distribution is the primary scale for supplying a food, (d) the product occupies an agro-ecological niche, (e) a product is a co-product of another industry in the region, and (f) the product is marketed explicitly for its geographic provenance as a local or regional product. Illustrative examples of each role are provided from the research of the Enhancing Food Security in the Northeast (EFSNE) regional food systems project. The examples draw from a variety of methodological approaches including regional self-reliance analysis, product case studies, supply chain models, and examination of spatial and temporal patterns in crop and livestock production and marketing. While presented in the context of the Northeast, the typology would likely be valuable for characterizing other regions of the country. We need such a typology to better understand and communicate the value of geographically dispersed agricultural production to creating a resilient food system, thereby improving our decisions of how to respond to future agricultural challenges

Crop yield maps are valuable for many applications in precision agriculture, but are often inaccessible to growers and researchers wishing to better understand yield determinants and improve site-specific management strategies. A method for mapping sub-field crop yields from remote sensing imagery could increase the availability of crop yield maps. A variation of the scalable crop yield mapping approach (SCYM, Lobell et al. in Remote Sensing of Environment 164:324–333, 2015) was developed and tested for estimating sub-field maize (Zea mays L.) yields at 10–30 m without the use of site-specific input data. The method was validated using harvester yield monitor records for 21 site-years for irrigated and rainfed fields in eastern Nebraska, USA. Prediction error ranged greatly across site-years, with relative RMSE scores of 10.8 to 38.5%, and R2 values of 0.003 to 0.37. Significant proportional bias was detected in the predictions, but could be corrected with a small amount of ground truth data. Crop yield prediction accuracies without calibration were suitable for some precision applications such as mapping relative yields and delineating management zones, but model improvements or calibration datasets are needed for applications requiring absolute yield estimates.

Limited research has examined the rapid growth of farm to school (FTS) programs in the US. Qualitative interviews (n = 24) framed by Diffusion of Innovations theory were used to explore FTS program...

Plants often experience multiple sources of stress simultaneously, yet little is known about interactive effects of multiple stressors on plant metabolic responses. Plants are well known to respond to both drought and insect herbivory through the induced production of secondary metabolites. However, severe drought stress limits photosynthesis and may therefore inhibit the production of induced secondary metabolites in response to herbivory due to carbon limitation. On the other hand, drought-stressed plants may be primed to respond more strongly to herbivory due to hormonal crosstalk or redundancy of metabolites that are produced in response to drought and herbivory. We tested the interactive effects of drought and simulated herbivory in tea plants (Camellia sinensis (L.) Kuntze var. sinensis) grown in the field under varying rainfall interception treatments and then exposed to an exogenous methyl jasmonate (MeJA) treatment. We show that severe drought generally inhibits the induction of secondary metabolites by exogenous MeJA (simulated herbivory). However, a few volatile metabolites, including methyl salicylate, are more strongly induced by MeJA in severely drought-stressed plants compared to moderately stressed plants, possibly due to priming by drought stress. Our approach of using multiple levels of drought stress and a targeted/untargeted approach to measuring volatile metabolites was essential to discovering these patterns of induction. In addition to having implications for plant-herbivore interactions in the presence of abiotic stress, these results have important implications for tea quality.

Public concern about the environmental consequences of our diets is growing and regional food systems have emerged as one strategy to reduce these impacts. However, the potential environmental benefits of regional food systems are still largely untested and more empirical evidence is needed. Land and water are critical inputs to agriculture, but natural resource requirements and associated environmental impacts are highly dependent crop production location. This study used statistical analyses of crop yield and water footprint data to examine regional variability in land and water requirements and location‐specific tradeoffs between these resources. Regional land requirements and water requirements differed among most of the 17 fruit and vegetable crops we examined. Our results also showed inverse relationships between land and irrigation water requirements for eight crops, indicating that location‐specific tradeoffs between land and water resources exist for these crops. Understanding these regional differences and tradeoffs in natural resource requirements can help us evaluate the environmental implications of a more regionalized food system.

Food systems lie squarely at the intersection of several overarching goals of the UN and member states, as embodied in the Sustainable Development Goals, including eliminating poverty, hunger, and malnutrition in all its forms, achieving good health and well-being, while promoting environmental sustainability. The need for radical transformation of current food systems is inescapable if the world is to achieve one, let alone all, of these goals. Meeting this challenge will inevitably be disruptive to current food systems, carry costs, and be politically onerous. But the projected benefits far outweigh these difficulties. This commentary spells out the complexity of issues that need to be tackled to design and implement food systems that improve diets, nutrition, and health in an equitable fashion, while simultaneously respecting planetary boundaries. Six critical domains are identified that must be addressed for the successful transformation of food systems: 1) reinvent agriculture, 2) transform food environments for healthy diets, 3) mitigate climate change, 4) productively engage the private sector, 5) influence public policy priorities, and 6) establish true cost accounting of food. Because science is crucial for each of these domains, a research-driven strategy, emphasizing a collaborative process, is outlined. Bold, new, but technically and politically feasible actions are needed to effectively transform current food systems.

Pastures and rangelands are a dominant portion of global agricultural land and have the potential to sequester carbon (C) in soils, mitigating climate change. Management intensive grazing (MIG), or high density grazing with rotations through paddocks with long rest periods, has been highlighted as a method of enhancing soil C in pastures by increasing forage production. However, few studies have examined the soil C storage potential of pastures under MIG in the northeastern United States, where the dairy industry comprises a large portion of agricultural use and the regional agricultural economy. Here we present a 12-year study conducted in this region using a combination of field data and the denitrification and decomposition (DNDCv9.5) model to analyze changes in soil C and nitrogen (N) over time, and the climate impacts as they relate to soil carbon dioxide (CO

Agricultural production on farms and ranches in the U.S. contributes to the food supply and the food system on local, regional, national, and global scales. Increasing production at the regional scale—the focus of this research—depends on accurately estimating current production and understanding the mechanisms and resource requirements of production shifts. The Produc­tion Team of the EFSNE Project undertook seven studies that focused on current and poten­tial production in the U.S. Northeast region, which includes nearly one-quarter of the popula­tion but only about 3% of national cropland. Here we summarize the results from these studies that: (1) estimate the regional self-reliance of primary crop, livestock products, and livestock feeds; (2) develop and implement a method to delineate urban, peri-urban, and rural zones around cities and analyze the distribution of food chain businesses across these zones; (3) assess crop yield trajectories to refine potential production increases associated with agricultural expansion into different land categories; and (4) model climate change and dietary impacts on yields and land use. The regional self-reliance of food crops varies widely, and the predominant agricultural use of land is for the production of animal feeds. The peri-urban zones contain significant agricultural production and concentrations of supply chain businesses. The potential to expand regional output via yield increases varies by crop and by land category and is strongly influenced by climate change. The diverse disciplines represented on the Production Team, along with significant leader­ship from graduate students and post-doctoral researchers, contributed to the broad array of studies completed.

Soil health is essential for agricultural sustainability and environmental quality yet may be degraded by intensive cropping practices. Improved cropping systems and management practices may greatly enhance soil properties associated with soil heath. Four different potato cropping systems, designed to address specific management goals of soil conservation (SC), soil improvement (SI), disease suppression (DS), and a status quo standard rotation (SQ), along with a non-rotation (PP) control, were evaluated for their effects on soil physical, chemical, and biological properties in field trials in Maine, USA. The purpose of the study was to determine how and to what extent these different cropping system approaches and practices would affect soil properties. Cropping systems were established in 2004 and actively managed through 2010, with potato crops also planted in subsequent years (2011−12) to examine residual effects. Cropping system significantly affected many parameters associated with soil health, with effects generally increasing over time as well as having lasting residual effects. All rotations increased aggregate stability, water availability, microbial biomass C, and total C and N compared to no rotation (PP), and 3-yr systems (SI, SC, DS) increased aggregate stability relative to the 2-yr system (SQ). The 3-yr systems with reduced tillage (SI and SC) also increased water availability and reduced bulk density relative to the other systems. However, the SI system, which included yearly compost amendments, resulted in greater increases in total and particulate organic matter (POM) C and N, active C, microbial biomass C, water availability, CEC, concentrations of P, K, Ca, Mg, and S, and lower bulk density than all other rotations. Cropping systems that incorporate management practices such as increased rotation length and the use of cover crops, green manures, reduced tillage, and, particularly, organic amendments, can improve soil physical, chemical, and biological properties associated with soil health.

ObjectiveTo examine the comparability of fruit and vegetable (F&V) intake data in the USA from 2001 to 2014 between data acquired from two national data collection programmes.DesignCross-sectional analysis. Linear regression models estimated trends in daily per capita intake of total F&V. Pooled differences in intake of individual F&V (n 109) were examined by processing form (fresh, frozen, canned, dried and juice).SettingWhat We Eat in America (WWEIA, 2001–2014) and Loss-Adjusted Food Availability data series (LAFA, 2001–2014).ResultsNo temporal trends were observed in daily per capita intake of total F&V from 2001 to 2014 using WWEIA and LAFA. Modest differences between WWEIA and LAFA were observed in mean pooled intake of most individual F&V.ConclusionsWWEIA and LAFA produced similar estimates of F&V intake. However, WWEIA may be best suited for monitoring intake at the national level because it allows for the identification of individual F&V in foods with multiple ingredients, and it is structured for sub-population analysis and covariate control. LAFA does retain advantages for other research protocols, specifically by providing the only nationally representative estimates of food losses at various points in the food system, which makes it useful for examining the adequacy of the food supply at the agricultural, retail and consumer levels.

One widely recognized strategy to meet future food needs is reducing the amount of arable land used to produce livestock feed. Of all livestock products, beef is the largest land user per unit output. Whether beef production results in feed-food competition or a net positive contribution to the food supply, however, may depend largely on whether marginal land is used to grow forage. The land use ratio (LUR) was developed by van Zanten et al. (2016a) to identify livestock systems that produce more animal source food than would be produced by converting their associated feed land to food crop production – a perspective that is not addressed within life cycle assessment (LCA). van Zanten et al. (2016a) used country-specific and farm-level land suitability data, the latter of which is not available in many countries. To assess the LUR of beef systems in the USA, which may use large grassland areas of potentially varying quality across scales, an intermediate approach between farm and country-scale estimation is needed. In this paper, we enhanced the LUR by integrating geospatial data for crop suitability and yield estimation at multiple scales. By doing so, the LUR will also become more widely applicable for other studies. We applied our enhanced LUR for a grass-fed beef (GF) system and a dairy beef (DB) system in the Northeastern USA, including multiple scenarios limiting land conversion. All systems had LURs greater than one, indicating they produce less protein than conversion of their suitable feed land base to food cropping would. Because a large fraction of the forage land used in the GF system was suitable for crop production and moderately productive, its LUR was 3–6 times larger (less efficient land use from a food supply perspective) than the DB system. Future research should explore mechanisms to reduce the LUR and life cycle environmental burdens of both regional production systems.

Opportunities for alternative swine production and marketing are emerging across the value chain. Given the developing nature of the differentiated pork industry, measurements of niche performance and success are not yet fully known. For this reason, the objectives of this study were to determine performance metrics across all major life phases for niche pork production and compare such metrics with national averages of conventional commodity pork production. Additionally, this study aimed to quantify producers’ reasoning and barriers to successfully raising niche swine. Niche meat producers in the USA self-identified for this study (n = 176); their swine production had alternative characteristics that included small- to mid-sized farms, farrow-to-finish operations, heritage breeds, housing with bedding and outdoor or pasture access, no use of antibiotics (sub-therapeutic for growth promotion or no antibiotics ever), vegetarian feed, diverse agricultural enterprises and alternative marketing avenues. This study focused on the metric categories regarding reproduction, mortality, culling and growth characteristics. The niche system produced approximately 15% fewer weaned piglets per bred sow per year than the conventional system due to fewer breeding cycles, smaller litters and higher piglet mortality in alternative production. Similarly, niche production finished 12% fewer hogs per bred sow per year than conventional production. Regarding age benchmarks of finishing and breeding, the niche system averaged 18 additional days to finish hogs at a standardized market weight of 124 kg. Likewise, niche production gilts were first bred at 283 days, whereas conventional production breeds gilts at 225 days. All directly comparable metrics were found to be statistically significant with 95% confidence for the one-sample test of means. Regarding farmer attitudes toward niche pork, survey participants shared personal reasons for raising swine and barriers to successful niche production. Choosing niche over commodity swine, participants’ reasons were grouped into three intra-related categories: (1) farm and producer viability, (2) animal and environmental welfare, and (3) consumer preference and taste. Despite these benefits, participants were faced with numerous challenges, which were organized into four intra-related categories: (1) alternative production requirements, restrictions and knowledge; (2) access and affordability of credit and inputs; (3) alternative supply chain for processing, marketing and customers; and (4) non-niche production competition and governmental policies. In sum, the success of these niche pork operations equates to high welfare for the pigs, economic viability for the operation, personal enjoyment for the farmer, customer satisfaction with meat flavor and quality, and responsible environmental practices, inclusive of many components of an alternative food system.

Innovative strategies are needed to improve the sustainability of beef production and consumption systems. Increasing reliance on regional or local food systems may improve resilience, and consumer demand for such foods is high. In the Northeastern U.S., the dairy sector may provide beef at a low environmental cost relative to other systems due to multi-functionality (i.e., milk and meat outputs). Additionally, landscape and market factors indicate suitability and demand for regional grass-fed beef. We used ISO-compliant life cycle assessment (LCA) to quantify the environmental burdens of grass-fed beef with management-intensive grazing (GF) and confinement dairy beef (DB) production systems in the Northeastern U.S. The impact scope included global warming potential, eutrophication and acidification potential, fossil fuel and water depletion, and agricultural land use. The foundation of the production system models was a herd-level, life cycle livestock feed requirements model, which we adapted and applied for the first time within LCA. Per kg carcass weight beef produced, DB had lower global warming potential, eutrophication potential, acidification potential, and agricultural land use than GF with higher fossil fuel depletion and water depletion. Calculating eutrophication and acidification per hectare agricultural land resulted in lower impacts for GF compared to DB. Maintaining the breeding herd accounted for over half of GF (60%) and DB (52%) impacts on average across categories. Sensitivity analyses indicated potential pasture carbon sequestration and lower enteric methane emissions under management-intensive grazing may substantially reduce the carbon footprint of GF (though not lower than DB), which should be explored with further research. Future research should also examine holistic strategies to reduce regional GF and DB system footprints, such as substituting food waste for traditional feeds and accounting for ecosystem services provided by pasture-based farming systems within LCA.

White mold or Sclerotinia stem rot (Sclerotinia sclerotiorum (Lib) de-Bary) was first observed on soybean varieties in a variety trial at the Maine Agricultural and Forest Experiment Station, Presque Isle, and in commercial soybean fields in late July and August 1997. Symptoms and signs included stem bleaching, fluffy white mycelial growth on soybean stems and foliage, and presence of sclerotia typical of white mold. Disease assessment, based on symptoms, was conducted on the varieties in the trial in the experiment station. Field observations on disease occurrence were also conducted in commercial soybean fields in northern Maine. In the variety trial experiment, mean incidence (%) of white mold ranged from 0 to 6.8% on Lambert, APK007, P9092, P9132, and Stine varieties. No white mold was detected on P9071, P9007, Korada, Bravor, Ugo, APK020, and Aquillon varieties. Of the infected varieties, incidence of white mold was detected in 10 of 33 fields examined. This is the first report of the occurrence of white mold on soybean in Maine. Because of large-scale commercial potato production in the region, and previous occurrence of white mold on potato, it is likely that the pathogen is present in soils of various commercial potato fields in Maine. Precautions should, therefore, be taken in introducing resistant varieties and ensuring proper rotation and cropping sequences as soybean production increases in Maine.

To support food security for current and future generations, there is a need to understand the relation between sustainable diets and the health of a population. In recent years, a number of studies have investigated and compared different dietary patterns to better understand which foods and eating patterns have less of an environmental impact while meeting nutritional needs and promoting health. This systematic review (SR) of population-level dietary patterns and food sustainability extends and updates the SR that was conducted by the 2015 US Dietary Guidelines Advisory Committee, an expert committee commissioned by the federal government to inform dietary guidance as it relates to the committee's original conclusions. In the original SR, 15 studies met the criteria for inclusion; since then, an additional 8 studies have been identified and included. The relations between dietary intake patterns and both health and environmental outcomes were compared across studies, with methodologies that included modeling, life cycle assessment, and land use analysis. Across studies, consistent evidence indicated that a dietary pattern higher in plant-based foods (e.g., vegetables, fruits, legumes, seeds, nuts, whole grains) and lower in animal-based foods (especially red meat), as well as lower in total energy, is both healthier and associated with a lesser impact on the environment. This dietary pattern differs from current average consumption patterns in the United States. Our updated SR confirms and strengthens the conclusions of the original US Dietary Guidelines Advisory Committee SR, which found that adherence to several well-characterized dietary patterns, including vegetarian (with variations) diets, dietary guidelines-related diets, Mediterranean-style diets, the Dietary Approaches to Stop Hypertension (DASH) diet, and other sustainable diet scenarios, promotes greater health and has a less negative impact on the environment than current average dietary intakes.

Soilborne potato diseases and soil microbial community characteristics were evaluated over 8 years in different potato cropping systems designed to address specific management goals of soil conservation, soil improvement and disease suppression. Results were compared to a standard rotation and non‐rotation control in field trials in Maine. Standard rotation consisted of barley underseeded with red clover, followed by potato (2‐year). Soil‐conserving system (SC) featured an additional year of forage grass and reduced tillage (3‐year, barley/timothy–timothy–potato). Soil‐improving system (SI) added yearly compost amendments to SC, and the disease‐suppressive system (DS) featured crops with known disease‐suppressive capability (3‐year, mustard/rapeseed–sudangrass/rye–potato). Systems were established in 2004, evaluated with and without irrigation, and actively managed until 2010, with potato also planted in 2011 and 2012 to examine residual effects. All rotations reduced soilborne diseases black scurf and common scab, and increased yield after one rotation cycle (3 years), but diseases increased overall after two rotation cycles. DS maintained lower soilborne disease levels than all other rotations, as well as high yields, throughout the study. Cropping system effects became more pronounced after multiple cycles. SI system and irrigation both resulted in higher yields, but also higher levels of soilborne disease. Cropping system and irrigation effects were significant even after systems were no longer maintained. Soil microbial community data showed significant changes associated with cropping system, and differences increased over time. Cropping system strategy had significant and lasting effects on soil microbiology and soilborne diseases, and can be used to effectively enhance potato production.

The production of livestock feed in the USA is geographically concentrated, which poses several risks. Extreme weather events and disease outbreaks have the potential to disrupt production in these areas, which could reduce the national output of meat, dairy and eggs. Additionally, geographically concentrated livestock and feed production systems have been observed to contribute excessive nutrient loads to surrounding soil and water bodies, thereby threatening environmental sustainability. Geographic relocation of production systems has been proposed as an adaptation strategy to increase system resilience and this could take the shape of more geographically dispersed livestock feed production. We estimate the degree to which the demand for meat, dairy and eggs in the Northeast region is met with current levels of regional feed and livestock production, a term that we refer to as regional self-reliance. We combine mean annual (2001–2010) data on Northeast regional land use; crop output; meat, dairy and egg output; and food consumption with a livestock feed requirements model. An annual mean of over 6.1 million ha of land in the Northeast was dedicated to livestock feed from 2001 to 2010, with nearly 80% located in just three states (Pennsylvania, New York and West Virginia). The region is a net importer of livestock feed (in terms of total digestible nutrients and crude protein), as well as meat, dairy and eggs (in terms of total human-edible energy and protein). This is the result of a confluence of long-term regional trends that include the movement of agricultural production out of the region with a concomitant increase in the regional population and an increase in the national demand for meat, dairy and eggs. Limited slaughter output in the region is a key limiting factor to increasing the region's self-reliance for livestock products.

Summary Background Evidence-based nutrition policy is a key mechanism to promote planetary health. In the USA, the Dietary Guidelines for Americans are the foundation of nutrition policy and guide more than US$80 billion in federal spending. Recent attempts have been made to incorporate sustainability into the development of the Dietary Guidelines. However, the sustainability of the 2015–20 Dietary Guidelines remains unclear; research has not yet assessed the environmental impacts of the distinct healthy patterns recommended by the policy. Methods In this modelling study done at the University of New Hampshire (Durham, NH, USA), we analysed the healthy US-style (US), healthy Mediterranean-style (MED), and healthy vegetarian (VEG) patterns recommended in the 2015–20 Dietary Guidelines for Americans. Food groups and subgroups consisted of 321 commonly consumed foods, with group composition predetermined by the US Department of Agriculture. We compiled and used multiple datasets to assign environmental burdens to foods, focusing on six impact categories of policy importance: global warming potential, land use, water depletion, freshwater and marine eutrophication, and particulate matter or respiratory organics. We did life cycle impact assessments for each of the three diet patterns and compared the six impact categories between the patterns. We also analysed the proportion contribution of the food groups to each impact category in each of the diet patterns. Findings The US and MED patterns had similar impacts, except for freshwater eutrophication. Freshwater eutrophication was 31% lower in the US pattern than the MED pattern, primarily due to increased seafood in the MED pattern. All three patterns had similar water depletion impacts, with fruits and vegetables as major contributors. For five of the six impacts, the VEG pattern had 42–84% lower burdens than both the US and MED patterns. Reliance on plant-based protein and eggs in the VEG pattern versus emphasis on animal-based protein in the other patterns was a key driver of differences, as was a lower overall protein foods recommendation in the VEG pattern. Interpretation The recommended patterns in the Dietary Guidelines for Americans might have starkly different impacts on the environment and other dimensions of human health beyond nutrition. Given the scale of influence of the Dietary Guidelines for Americans on food systems, incorporating sustainability into their development has the potential to have great benefit in terms of long-term food security. Funding None.

Plant-climate interactions affect the edible crop composition, impacting flavor, nutrition, and overall consumer liking. In this study, principal components analysis was used to assess the macro- and micronutrient metal concentrations in pre-monsoon (spring), monsoon (summer), and post-monsoon (autumn) tea (Camelia sinensis (L.) Kuntze) from Yunnan Province, China in 2014–2016. Statistical differences were observed (p = 1.35E-24). Fe, Ca, Mg, Mn, Al, and Ba concentrations were higher in June (monsoon) than in March (pre-monsoon) and September (post-monsoon) compared to Pb, K, Cu, Zn, and Na, which were higher in March and September. Although Fe, Ca, Mg, Mn, Al, and Ba concentrations increased during the monsoon season, sensory analysis did not detect metallic taste in either minimally processed or farmer-processed (commercial) teas. This finding shows the seasonal differences in flavor were due to striking differences in organic chemical composition and concentration.

Climate effects on crop quality at the molecular level are not well-understood. Gas and liquid chromatography–mass spectrometry were used to measure changes of hundreds of compounds in tea at different elevations in Yunnan Province, China. Some increased in concentration while others decreased by 100’s of percent. Orthogonal projection to latent structures-discriminant analysis revealed compounds exhibiting analgesic, antianxiety, antibacterial, anticancer, antidepressant, antifungal, anti-inflammatory, antioxidant, anti-stress, and cardioprotective properties statistically (p = 0.003) differentiated high from low elevation tea. Also, sweet, floral, honey-like notes were higher in concentration in the former while the latter displayed grassy, hay-like aroma. In addition, multivariate analysis of variance showed low elevation tea had statistically (p = 0.0062) higher concentrations of caffeine, epicatechin gallate, gallocatechin, and catechin; all bitter compounds. Although volatiles represent a small fraction of the total mass, this is the first comprehensive report illustrating how normal variations in temperature, 5 °C, due to elevational effects impact tea quality.

Seasonal variation in tea (Camellia sinensis (L.) Kuntze; Theaceae) chemistry was investigated using automated sequential, multidimensional gas chromatography/mass spectrometry (GC–GC/MS). Metabolite libraries were produced for teas harvested from the Bulang Mountains in Yunnan, China before and after the onset of the East Asian Monsoon. A total of 201 spring and 196 monsoon metabolites were identified, with 169 common and 59 seasonally unique compounds. An additional 163 metabolites were detected but their identity could not be confirmed. Spectral deconvolution of GC/MS data was used to measure the relative concentrations in the teas. Within each family individual metabolite concentrations increased, decreased and stayed the same. The major constituents in both teas were linalool (28%), geraniol (13%), α-terpineol (10%), hotrienol (4%) and nerol (3%). This work provides the foundation to monitor seasonal variations of tea chemistry.

A sustainability transition will require a clear understanding of the environmental impacts of human food needs. To this end, accurate data on the feed requirements of livestock production are essential. Unfortunately, approaches used to estimate overall feed conversion ratios per unit output of livestock product vary and the reported values used in environmental analyses may be inconsistent. This paper presents a spreadsheet model for determining the aggregate, herd (flock) level feed needs of six major livestock commodities (beef, chicken, dairy, eggs, pork, and turkey) based on contemporary U.S. production practices. In this model, each system is represented as a set of stocks and flows, each of which is estimated based on performance metrics, such as reproduction and mortality rates. Parameter estimates were made primarily from U.S. government surveys or comparable peer-reviewed literature. Nutritional needs of livestock were based primarily from National Research Council reports. The model estimates the feed intake and ration composition for each life stage of each livestock system. Results were summarized as feed conversion ratios per unit output, herd (flock) average ration composition, and land use requirements for all feed ingredients. The findings confirm conventional wisdom that the total feed use efficiency of livestock products varies widely across livestock systems. However, the differences appear more subtle when the requirements for individual feed ingredients are considered. Similarly, the land requirements of livestock production also vary widely, but the differences are more nuanced when viewed in light of the land quality required to supply each feed ingredient. While the findings are consistent with some other past efforts to determine feed and land use efficiency of livestock production, greater transparency and consistency is needed in this area of research.

Farms producing similar products have become increasingly concentrated geographically over the past century in the United States (US). Due to the concentration of food production, a disruption in key production areas may reduce the availability of certain foods nationwide. For example, climate change poses such a threat, with projections of altered precipitation patterns, increased temperature and pest outbreaks, which may result in reduced crop yields and geographic shifts in crop adaptation. Analyses of the degree to which US regions can satisfy the food needs of their resident populations—a concept we refer to as regional self-reliance (RSR)—are therefore warranted. We focus on the Northeast region because of its high population density and declining agricultural landbase. Our objectives are to: (1) determine how agricultural land is used in the Northeast region; (2) determine the variety and amount of foods produced; and (3) analyze the relationship between food consumption and agricultural output. Annual (2001–2010) data on land area, yield and output of all crops and major livestock categories, as well as seafood landings, were catalogued. National annual (2001–2009) data on food availability were used as a proxy for estimates of food consumption, and these data were downscaled to a regional level and compared with regional production data in order to estimate RSR. In the Northeast region, approximately 65% of land in farms contributed directly to the food supply from 2001 to 2010, although this varied significantly across states. Just over one-half of all land in farms in the region was devoted to the production of livestock feed. The region produced >100 food crops annually from 2001 to 2009, and vegetables represented the majority of food crop production by weight. Chicken accounted for the largest weight of meat products produced. Compared to the Northeast region's share (~6%) of total land in farms in the nation, it accounted for disproportionately higher amounts of the national production of dairy (16%), eggs (13%), chicken (9%), lamb (7%) and vegetables (7%). However, the region accounted for ~22% of the national population and therefore produced a disproportionately low share of food on a per capita basis. RSR for plant-based foods was lowest for pulses (7%) and highest for vegetables (26%). There are four specific factors in the RSR in our analysis, each of which could result in substantial shifts (upward or downward) of the RSR in the future: land used for agriculture, crop (or animal) productivity, population and dietary preferences.

A session was convened at the ASN Nutrition 2018 annual meeting to discuss the scientific evidence on what makes individual foods and dietary patterns both sustainable and nutritious, and the role of various stakeholders in the actions needed to implement food systems that deliver “sustainable nutrition.” This commentary is a structured synthesis of the primary themes of the session, and concludes with a set of implications and research recommendations. Consumers are becoming increasingly aware of the environmental implications of what they eat, and there is growing momentum toward changes in the food system. However, ecological challenges persist, and although the literature is evolving, methodologic improvements are needed in the scientific approaches to address dietary patterns that meet nutrition needs in more holistically sustainable ways. The session concluded with encouraging evidence that consumers, businesses, scientists, and policy-makers are collectively “rising to the occasion,” with cross-sectoral partnerships to address these issues.

Organic dairy (OD) production is increasing in the Northeastern United States due to consumer demand. Some physicochemical properties of OD manure differ from conventional dairy (CD) manure, which could influence nutrient cycling and soil fertility differently when OD manure is applied as fertilizer to meet plant N demands. Effects of OD manure on activities of acid phosphomonoesterase (ACP), alkaline phosphomonoesterase (ALP), phosphodiesterase (PDE), available soil phosphorus (P), and plant growth were investigated in a greenhouse study, where sorghum-sudangrass (Sorghum bicolor subsp. drummondii) was fertilized with manures from 13 organic dairies in Maine, CD manure, or NH4NO3. Soil phosphatase activities and modified Morgan P were determined at planting and after 16 weeks of plant growth. Plant growth did not differ (P > 0.05) when fertilized with OD and CD manures or inorganic fertilizer. However, there was a wide range in growth with OD manure, which was negatively correlated to manure C:N and C:P (P 0.05). Of the three soil phosphatases, ACP activity was highest and increased with OD manure similarly to CD manure. There was a negative correlation (P < 0.01) between ACP activity and manure C:P ratio, suggesting that manure C content influences P cycling and may reduce P availability in soils amended with OD manure, in a manner similar to CD manure.

Four different potato cropping systems, designed to address specific management goals of soil conservation, soil improvement, disease suppression, and a status quo standard rotation control, were evaluated for their effects on soilborne diseases of potato and soil microbial community characteristics. The status quo system (SQ) consisted of barley underseeded with red clover followed by potato (2-year). The soil-conserving system (SC) featured an additional year of forage grass and reduced tillage (3-year, barley/timothy–timothy–potato). The soil-improving system (SI) added yearly compost amendments to the SC rotation, and the disease-suppressive system (DS) featured diverse crops with known disease-suppressive capability (3-year, mustard/rapeseed–sudangrass/rye–potato). Each system was also compared with a continuous potato control (PP) and evaluated under both irrigated and nonirrigated conditions. Data collected over three potato seasons following full rotation cycles demonstrated that all rotations reduced stem canker (10 to 50%) relative to PP. The SQ, SC, and DS systems reduced black scurf (18 to 58%) relative to PP; SI reduced scurf under nonirrigated but not irrigated conditions; and scurf was lower in DS than all other systems. The SQ, SC, and DS systems also reduced common scab (15 to 45%), and scab was lower in DS than all other systems. Irrigation increased black scurf and common scab but also resulted in higher yields for most rotations. SI produced the highest yields under nonirrigated conditions, and DS produced high yields and low disease under both irrigation regimes. Each cropping system resulted in distinctive changes in soil microbial community characteristics as represented by microbial populations, substrate utilization, and fatty acid methyl-ester (FAME) profiles. SI tended to increase soil moisture, microbial populations, and activity, as well result in higher proportions of monounsaturated FAMEs and the FAME biomarker for mycorrhizae (16:1 ω6c) relative to most other rotations. DS resulted in moderate microbial populations and activity but higher substrate richness and diversity in substrate utilization profiles. DS also resulted in relatively higher proportions of FAME biomarkers for fungi (18:2 ω6c), actinomycetes, and gram-positive bacteria than most other systems, whereas PP resulted in the lowest microbial populations and activity; substrate richness and diversity; proportions of monounsaturated and polyunsaturated FAME classes; and fungal, mycorrhizae, and actinomycete FAME biomarkers of all cropping systems. Overall, soil water, soil quality, and soilborne diseases were all important factors affecting productivity, and cropping systems addressing these constraints improved production. Cropping system approaches will need to balance these factors to achieve sustainable production and disease management.

Objective To determine predictors of fluid milk waste in a Breakfast in the Classroom School Breakfast Program. Design Cross-sectional with 3 repeated measures/classroom. Setting Elementary schools in a medium-sized, low-income, urban school district. Participants Twenty third- through fourth-grade classrooms across 6 schools. Main Outcomes Dependent variables include percentage of total and served milk wasted. Independent variables included observed daily menu offerings, program factors, and teacher and student behavior. Analysis Descriptive statistics were used to characterize variables across classrooms and schools. Multilevel mixed-effects models were used to test associations between predictors and outcomes of interest. P ≤ .05 was considered statistically significant. Results Total milk waste increased 12% when juice was offered and 3% for each additional carton of unserved milk. Teacher encouragement to take and/or consume breakfast was associated with a 5% and 9% increase in total and served milk waste, respectively. When students were engaged in other activities in addition to eating breakfast, total milk waste decreased 10%. Conclusions and Implications Beverage offerings were predictive of greater total milk waste. Teacher and student behavior also appeared to influence milk consumption. Findings suggest that specific changes to School Breakfast Program implementation policies and practices could have an important role in waste mitigation.

Proper management of manure nitrogen (N) requires the ability to match the rate and extent of manure N availability with crop needs. This includes recognizing the potential importance of N contributions from residual manure N that accumulates with repeated applications. Nitrogen availability relative to barley needs was assessed in plots with 13–16 years continuous histories of contrasting manure-based (solid-bedded beef) and fertilizer-based soil treatments in the Maine Potato Ecosystem Project. Soil and barley samples were collected every 7–14 days during 2003–2005, and once in 2006. Barley dry matter and N content were equivalent between the two systems. In the manure-based system, temporal patterns of N availability were more synchronous with early season crop needs than in the fertilizer-based system, but continued mineralization after harvest was also observed. In 2004–2006, samples were collected from subplots where manure/fertilizer was withheld to estimate the proportion of available N originating from current versus previous manure applications. Apparent N recovery of current years’ applications of manure organic N was 8–11% and less than predicted by a standard decay series model for beef manure (25%), highlighting the need to adjust manure N credits for crops with shorter growing seasons and lower N uptake capacities than corn. The relative contribution of residual manure N to total manure N uptake was greater than predicted from the decay series model, providing support for a residual N effect from repeated manure applications that is not accounted for in standard manure recommendations.

A reliable laboratory index ofN availability would be useful for making N recommendations, but no single approach has received broad acceptance across a wide range of soils. We compared several indices over a range of soil conditions to test the possibility of combining indices for predicting potentially mineralizable N (N 0 ). Soils (0-5 and 5-15 cm) from nine tillage studies across the southern USA were used in the evaluations. Long-term incubation data were fit to a first-order exponential equation to determine N 0 , k (mineralization rate), and N 0 * (N 0 estimated with a fixed k equal to 0.054 wk -1 ). Out of 13 indices, five [total C (TC), total N (TN), N mineralized by hot KCI (Hot_N), anaerobic N (Ana_N), and N mineralized in 24 d (Nmin_24)] were strongly correlated to N 0 (r > 0.85) and had linear regressions with r 2 > 0.60. None of the indices were good predictors ofk. Correlations between indices and N 0 * improved compared with N 0 , ranging from r = 0.90 to 0.95. Total N and Hush of CO 2 determined after 3 d (Fl_CO2) produced the best multiple regression for predicting N 0 (R 2 = 0.85) while the best combination for predicting N 0 * (R 2 = 0.94) included TN, Fl_CO2 Cold_N, and NaOH_N. Combining indices appears promising for predicting potentially mineralizable N, and because TN and Fl_CO2 are rapid and simple, this approach could be easily adopted by soil testing laboratories.

Crop and soil management may modify canopy and belowground microclimate, but their effects on potential development and control of early blight are not well documented. Several management systems (Status Quo, Soil Conserving, Soil Improving (SI), Disease Suppressive, and Continuous Potato) were evaluated for their effects on early blight potential under irrigated and rainfed conditions. In 2006 and 2007, microclimatic data at the canopy level were recorded with a data logger. Early blight incidence and severity was determined by visually assessing symptoms. Disease incidence and lesion numbers varied among cropping systems and between years. Disease incidence ranged from 31 to 64% (2006) and 12 to 43% (2007), and was significantly higher with the Continuous Potato system than with Disease Suppressive, Status Quo, Soil Conserving, and SI systems. The relationships of incidence and disease severity with microclimate varied and were mostly non-significant, suggesting that the chosen variables were not reflective of pathogen development. Incidence was significantly associated with cropping systems. Disease prediction based on the Tom-Cast model was not correlated with observed disease levels. This research demonstrated that early blight disease is enhanced through continuous potato production.

Delayed tillage and the inclusion of cover crops can substantially reduce erosion in intensively tilled potato systems. Both of these practices can potentially impact potato (Solanum tuberosum L.) yield and quality via changes in soil temperature and soil water status, and suppression or enhancement of soil-borne diseases. Research was conducted over six rotation cycles at two Maine locations to evaluate the effects of timing of primary tillage (fall vs. spring) and cover crop [none, red clover (Trifolium pratense L.), ryegrass (Lolium perenne L.), or winter rapeseed (Brassica napus L.)] on grain yield, ground cover, and tuber yield and quality within the context of 2-year barley (Hordeum vulgare L.)]–potato rotations. Delaying primary tillage until spring, immediately before planting potato, resulted in higher soil water content early in the growing season (before or immediately after planting) in some rotation cycles, and also provided nearly complete ground cover during potentially erosive periods in fall and early spring. The inclusion of clover or ryegrass cover crops had small, positive effects on the proportion of the soil surface covered by crop residue (determined by the line intercept method) in both tillage systems. A significant tillage effect on total tuber yield was seen in only one rotation cycle, when delaying tillage until spring reduced yield by about 12%. Cover crop treatments had no effect on total tuber yield, and neither tillage or cover crop affected the proportion of marketable tubers. Tillage did not affect black scurf (Rhizoctonia solani Kuhn) and common scab [Streptomyces scabiei (Thaxter) Lambert & Loria], which were significantly reduced by red clover in some rotation cycles. This research shows that conservation practices can be implemented, including delaying primary tillage until spring and including underseeded cover crops during the grain phase of the rotation, while maintaining potato yield.

A field study was conducted to determine nitrogen (N) mineralization from broiler litter (BL) in two Coastal Plain soils of differing texture, sandy (Tifton loamy sand) or clayey (Greenville sandy clay loam). These soils represented the broad range in surface textures commonly found in soils used for agricultural production in the southeastern Coastal Plain. Published protocols used for the study were designed by the ARS mineralization team. In addition to measuring ammonium (NH4-N) and nitrate (NO3-N) in the soil as a measure of N mineralization, both total C and total N were measured to determine the impact of a single BL amendment on C sequestration and N accumulation. Amounts of N in the soil from BL mineralization over 70 days were identical for both soils, 46.4 mg N kg-1 soil (0.046%), but differences occurred in timing of the mineralization processes. In the sandy Tifton soil, depletion of NH4-N and nitrification of the NH4-N to NO3-N occurred simultaneously. The NH4-N from the BL was depleted in 21 days while peak NO3-N concentrations in the soil were found at 28 days. In the clayey Greenville soil, NH4-N concentrations from BL mineralization increased for 21 days and then decreased until reaching background levels by 70 days. Nitrate concentrations never did increase in the BL amended Greenville soil, indicating both that the nitrification rate was much slower than the ammonification rate, and most likely, that what NO3-N was produced was lost from the soil by denitrification under wet conditions. The combination of soil textural and microclimate differences along with greater protection of the BL residues in the clayey soil than in the sandy soil are believed responsible for the observed N mineralization differences between the two soils. Previous research has shown that N mineralization rate is positively correlated with sand content and negatively correlated with clay content of soils, and the results of this study concurred with those findings. Measurements of total C and total N in both Coastal Plain soils showed that overall increases were small with a single BL amendment, and it was concluded that long-term studies are needed to investigate C sequestration and N accumulation. It was concluded from the study that there is a high probability that BL mineralization rates will be significantly slower on the more clayey Coastal Plain soils than on very sandy ones, and that farm managers should take these rates into consideration when planning timing and amounts of BL applications.

Efficiently controlling soil water content with irrigation is essential for water conservation and often improves potato yield. Volumetric soil water content (?v) in relation to irrigation, plant uptake, and yield in potato hills and replicated plots was studied to evaluate four water management options. Measurements of ?v using a hammer driven probe were used to derive a ?v index representing the relative ?v status of replicated plots positioned along a hill slope. Time series for ?v were determined using time domain reflectometry (TDR) probes at 5 and 15 cm depths at the center, shoulder, and furrow locations in potato hills. Sap flow was determined using flow collars in replicated field plots for four treatments: un-irrigated, sprinkler, surface drip, and sub-surface drip irrigation (40 cm depth). Irrigated yields were high/low as the ?v index was low/high suggesting ?v excess was a production problem in the wetter portions of the study area. The diurnal pattern of sap flow was reflected in the ?v fluctuation it induces at hill locations with appreciable uptake. Hill locations with higher plant uptake were drier as was the case for the 5 cm (dry) depth relative to the 15 cm (wet) depth and for locations in the hill (dry) relative to the furrow (wet). The surface drip system had the lowest water use requirement because it delivers water directly to the hill locations where uptake is greatest. The sub-surface drip system wetted the hill gradually (1�2 days). Measurement of the ?v index prior to experimental establishment could improve future experimental design for treatment comparisons