Abstract Food wastage represents the loss of both economic and resource investments. Incorporation of recovered food and food scraps, defined as the potentially edible organic matter left over from the preparation, sale, and consumption of food, into animal feed is a potential strategy to reduce food wastage and recover some of the embedded resources within the residual food material. There is a need to align recovered food and food scraps’ nutritional quality, chemical and biological safety with scalable and feasible processing requirements that dovetail with the nutritional requirements of food animals. This review examines the feasibility of incorporating treated post-consumer food scraps into poultry feed, which currently represent the most consumed animal protein on the planet. The review summarizes the broad nutritional composition of post-consumer food scraps, toxicological considerations associated with incorporating food scraps into poultry feed, food scrap pre-treatments related to feed applications and feeding studies that incorporated post-consumer food scraps into animal feed rations. Research appears to indicate that sterilization through heat treatment is sufficient to control pathogenic microorganism contamination in recovered food. Other contaminants such as mycotoxins, heavy metals, microplastics, biogenic amines, antinutritional factors cannot always be removed from recovered food and subsequently, infrastructure to survey levels of contamination in recovered food to be used in concert with developing technologies to better remove these contaminants is recommended. Subsequently, the review illustrates that pre-treatments in concert with surveillance of incoming recovered food and food scraps may be used to ensure the safety of incorporating such material into poultry feed. Studies show large variability in the nutritional composition of consumer food scraps, but on average, lipid and fiber levels are higher in recovered food scraps compared to maize and soybean meal, while protein levels are higher than in maize and lower than in soybean meal. Feeding studies suggest an incorporation level of up to approximately 20% is associated with positive or neutral impacts on growth performance indicators
Small breweries have been growing in number and volume share in the US marketplace. Brewing is water- and energy-intensive, especially for small brewers who do not benefit from the same economies of scale as large brewers. A systematic approach to characterizing the water and energy flows in small breweries will help researchers and process owners identify opportunities for efficiency improvement by reducing waste. The information from such analysis yields granular information about where water and energy (electrical and thermal) are embedded into beer. It also contextualizes a small brewery's specific water and energy consumption relative to peer breweries, providing a quantitative basis for decision-making that ultimately impacts economic competitiveness. In the present work, a case study is performed on a microbrewery in northern California. Visualization tools are provided that delineate how water and energy flow through the brewery. Specific electrical energy consumption was 183.7 MJ per US beer barrel (bbl) (1.6 MJ/L) packaged in the first half of 2018, thermal energy 489.4 MJ/bbl (4.2 MJ/L), water 12.8 bbl consumed/bbl (12.8 L/L), and wastewater 10.8 bbl discharged/bbl (10.8 L/L). These specific resource consumptions are placed into context relative to other small breweries. The metrics are high due to general inefficiency relative to peer facilities, reverse economies of scale in small breweries, and associated utility costs impacted by geographic location. Overall utility costs were $26.95 per bbl packaged vs. $16.01 for similar-sized breweries. This analysis sheds light on the virtuous cycle of how reducing one input in the beer-water-energy nexus will often lead to other resources being conserved as well, due to the overlapping nature of their embedment in the final product.
Attachment of the plant pathogen Agrobacterium tumefaciens to host plant cells is an early and necessary step in plant transformation and agroinfiltration processes. However, bacterial attachment behavior is not well understood in complex plant tissues. Here we developed an imaging-based method to observe and quantify A. tumefaciens attached to leaf tissue in situ. Fluorescent labeling of bacteria with nucleic acid, protein, and vital dyes was investigated as a rapid alternative to generating recombinant strains expressing fluorescent proteins. Syto 16 green fluorescent nucleic acid stain was found to yield the greatest signal intensity in stained bacteria without affecting viability or infectivity. Stained bacteria retained the stain and were detectable over 72 h. To demonstrate in situ detection of attached bacteria, confocal fluorescent microscopy was used to image A. tumefaciens in sections of lettuce leaf tissue following vacuum-infiltration with labeled bacteria. Bacterial signals were associated with plant cell surfaces, suggesting detection of bacteria attached to plant cells. Bacterial attachment to specific leaf tissues was in agreement with known leaf tissue competencies for transformation with Agrobacterium. Levels of bacteria attached to leaf cells were quantified over time post-infiltration. Signals from stained bacteria were stable over the first 24 h following infiltration but decreased in intensity as bacteria multiplied in planta. Nucleic acid staining of A. tumefaciens followed by confocal microscopy of infected leaf tissue offers a rapid, in situ method for evaluating attachment of A. tumefaciens' to plant expression hosts and a tool to facilitate management of transient expression processes via agroinfiltration.
Large, ground-mounted photovoltaic solar farms (GPVs) are expanding worldwide to support climate change mitigation and the transition towards a low-carbon economy. Few studies have explored the ecological impacts of tracking GPVs and maintenance activities for utility-scale operations on microclimate and vegetation patterns. Here, we explored the ecological impacts of a single-axis, tracking GPV and regular mowing in the Great Central Valley of California, United States. First, we developed an experimental framework of five unique "micro-patches" that characterize the heterogeneity of the dynamic microclimate and vegetation zones created by a single-axis, tracking GPV. Across these five micro-patch types, we evaluated nine above- and below-ground microclimate variables and 16 vegetation properties. We found that the micro-patches under PV panels reduced photosynthetic active radiation and wind speed by 90% and 46%, respectively, compared to open spaces along the facility perimeter. In contrast, soil surfaces in the open spaces were warmer and experienced faster soil moisture loss than micro-patches near or within array footprints during drought seasons. We found no significant difference in air temperature, relative humidity, and vapor pressure deficit across all micro-patches daily. We identified 37 plant species, of which 86% were exotic. Fully exposed to higher incoming solar radiation, plant communities in the open spaces experienced senescence the earliest compared to other micro-patches. We discuss the implications of our results for managing single-axis, tracking GPVs, particularly activities seeking to achieve enhanced control of the noxious weeds and other ecologically beneficial outcomes.
Large, ground-mounted photovoltaic solar projects (GPVs) are expanding rapidly worldwide, driven by their essential role in climate change mitigation and the transition to a low-carbon economy. With the global market for tracking systems projected to increase annually by 32% in capacity by 2050, understanding their ecological impacts, including those from their operation and management (O&M), is critical but understudied. This study presents the first comprehensive evaluation of microclimate and vegetation mosaics within a conventional, single-axis GPV managed through regular mowing. In the state of California’s Great Central Valley (United States), we developed a novel experimental framework to characterize five distinct “micro-patches” that capture the full spectrum of microclimate and vegetation zones modulated by the tracking PV system and O&M. Over a 12-month period, we monitored nine above- and belowground microclimate variables and 16 plant ecology metrics across these micro-patches. Beneath PV panels, photosynthetically active radiation decreased by 89%, and wind speed slowed by 46%, while open spaces within the GPV footprint exhibited greater soil surface temperatures (+2.4°C) and accelerated moisture loss (+8.5%) during drought periods. Furthermore, PV panel rotation influenced shading patterns throughout the day, creating temporal variability in air temperature and vapor pressure deficit. Plant surveys identified 37 species, 86% of which were non-native. Marked differences in vegetation across micro-patches indicated that GPVs drive changes in plant community composition, structure, and productivity. Compared to open spaces, vegetation near and within the PV array footprint displayed greater species richness (+8.4%), taller maximum height (+21%), reduced coverage of sun-loving plants (−71%), and less dead biomass accumulation (−26%), from shade-driven effects. These findings suggest the consideration of micro-patch-specific maintenance strategies and nature-based solutions to control invasive, exotic plant species, conferring opportunities to enhance operational, ecological, and socioeconomic sustainability while redressing the twin crises of climate change and biodiversity loss simultaneously.
