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Recording of Low-Oxygen Stress Response Using Chlorophyll Fluorescence Kinetics in Apple Fruit
(2023)
Long-term storage of apples (Malus x domestica, Borkh.) is increasingly taking place under Dynamic Controlled Atmosphere (DCA). The oxygen level is lowered to ≤ 1 kPa O2 and the apples are stored just above the Lower Oxygen Limit (LOL). Low oxygen stress during controlled atmosphere storage can lead to fermentation in apples if oxygen levels are too low. Chlorophyll fluorescence can be used to detect low-oxygen stress at an early stage during storage. The currently available non-imaging fluorescence systems often use the minimal fluorescence (Fo) parameter. In contrast, the use of chlorophyll fluorescence kinetics is insufficiently described. Therefore, this study aimed to gain more knowledge about the response of chlorophyll fluorescence kinetics to low oxygen stress in apples using a fluorescence imaging system. The results show that the kinetic fluorescence curves differ under aerobic and fermentation conditions. The fermentative conditions initiated a decrease in fluorescence intensity upon application of the saturation pulses during exposure to actinic light. This result was made at 18 °C and 2 °C ambient temperatures. Interestingly, the kinetic curve changed at 2 °C before fermentation products accumulated in the apples. Non-photochemical quenching (NPQ) decreased under fermentation conditions in the dark phase after relaxation. Upon entering the dark relaxation phase after Kautsky induction, ɸPSII began to increase. Under atmospheric oxygen conditions, ɸPSII reached values of 0.81 to 0.76, while under fermentation, ɸPSII values ranged from 0.57 to 0.44.
Hyperhydricity (HH) is one of the most important physiological disorders that negatively affects various plant tissue culture techniques. The objective of this study was to characterize optical features to allow an automated detection of HH. For this purpose, HH was induced in two plant species, apple and Arabidopsis thaliana, and the severity was quantified based on visual scoring and determination of apoplastic liquid volume. The comparison between the HH score and the apoplastic liquid volume revealed a significant correlation, but different response dynamics. Corresponding leaf reflectance spectra were collected and different approaches of spectral analyses were evaluated for their ability to identify HH-specific wavelengths. Statistical analysis of raw spectra showed significantly lower reflection of hyperhydric leaves in the VIS, NIR and SWIR region. Application of the continuum removal hull method to raw spectra identified HH-specific absorption features over time and major absorption peaks at 980 nm, 1150 nm, 1400 nm, 1520 nm, 1780 nm and 1930 nm for the various conducted experiments. Machine learning (ML) model spot checking specified the support vector machine to be most suited for classification of hyperhydric explants, with a test accuracy of 85% outperforming traditional classification via vegetation index with 63% test accuracy and the other ML models tested. Investigations on the predictor importance revealed 1950 nm, 1445 nm in SWIR region and 415 nm in the VIS region to be most important for classification. The validity of the developed spectral classifier was tested on an available hyperspectral image acquisition in the SWIR-region.
Dairy farming has been the subject of public debate on animal welfare for a number of years now. Animal welfare discussions on dairy farming often include the demand for more nature connectedness in this area. This study focuses on the divergent perspectives of consumers and scientists on the importance of more nature connectedness for animal welfare strategies in German dairy farming. Within Europe, Germany is the main producer of cow’s milk and an important industry in many rural areas in Germany is dairy farming. The insights presented are based on qualitative interviews with dairy farming and livestock researchers from Germany and Austria. A key finding of this study is that we need to look more closely at the actual content of nature claims in animal welfare debates. The scientists interviewed tend to see idealized conditions in animal welfare discussions with images of nature which in fact seldom lead to improved conditions in dairy farming and, even then, only to a limited extent. The scientists interviewed rate calls for more nature connectedness in dairy farming from the nonagricultural public as anti-modern, complexity-reducing, and normative. Nevertheless, some of the scientists interviewed did have valuable insights into the nonagricultural public’s criticism of dairy farming practices. These scientists argued, however, that animal welfare needs to differentiate between nature connectedness and the innate needs of cattle when it comes to animal welfare strategies. An important conclusion of the study is that more discussion formats are needed to promote the exchange of ideas between different social groups attempting to understand animal welfare in dairy farming.
Iron deficiency is still widespread as a major health problem even in countries with adequate food supply. It mainly affects women but also vegans, vegetarians, and athletes and can lead to various clinical pictures. Biofortification of vitamin C-rich vegetables with iron may be one new approach to face this nutritional challenge. However, so far, little is known about the consumer acceptance of iron-biofortified vegetables, particularly in developed countries. To address this issue, a quantitative survey of 1000 consumers in Germany was conducted. The results showed that depending on the type of vegetable, between 54% and 79% of the respondents were interested in iron-biofortified vegetables. Regression analysis showed a relationship between product acceptance, gender, and area of residence. In addition, relationships were found between consumer preferences for enjoyment, sustainability, and naturalness. Compared to functional food and dietary supplements, 77% of respondents would prefer fresh iron-rich vegetables to improve their iron intake. For a market launch, those iron-rich vegetables appear especially promising, which can additionally be advertised with claims for being rich in vitamin C and cultivated in an environmentally friendly way. Consumers were willing to pay EUR 0.10 to EUR 0.20 more for the iron-biofortified vegetables.
Background
The current development of sensor technologies towards ever more cost-effective and powerful systems is steadily increasing the application of low-cost sensors in different horticultural sectors. In plant in vitro culture, as a fundamental technique for plant breeding and plant propagation, the majority of evaluation methods to describe the performance of these cultures are based on destructive approaches, limiting data to unique endpoint measurements. Therefore, a non-destructive phenotyping system capable of automated, continuous and objective quantification of in vitro plant traits is desirable.
Results
An automated low-cost multi-sensor system acquiring phenotypic data of plant in vitro cultures was developed and evaluated. Unique hardware and software components were selected to construct a xyz-scanning system with an adequate accuracy for consistent data acquisition. Relevant plant growth predictors, such as projected area of explants and average canopy height were determined employing multi-sensory imaging and various developmental processes could be monitored and documented. The validation of the RGB image segmentation pipeline using a random forest classifier revealed very strong correlation with manual pixel annotation. Depth imaging by a laser distance sensor of plant in vitro cultures enabled the description of the dynamic behavior of the average canopy height, the maximum plant height, but also the culture media height and volume. Projected plant area in depth data by RANSAC (random sample consensus) segmentation approach well matched the projected plant area by RGB image processing pipeline. In addition, a successful proof of concept for in situ spectral fluorescence monitoring was achieved and challenges of thermal imaging were documented. Potential use cases for the digital quantification of key performance parameters in research and commercial application are discussed.
Conclusion
The technical realization of “Phenomenon” allows phenotyping of plant in vitro cultures under highly challenging conditions and enables multi-sensory monitoring through closed vessels, ensuring the aseptic status of the cultures. Automated sensor application in plant tissue culture promises great potential for a non-destructive growth analysis enhancing commercial propagation as well as enabling research with novel digital parameters recorded over time.
Primary Liver Cancers : Connecting the Dots of Cellular Studies and Epidemiology with Metabolomics
(2023)
Liver cancers are rising worldwide. Between molecular and epidemiological studies, a research gap has emerged which might be amenable to the technique of metabolomics. This review investigates the current understanding of liver cancer’s trends, etiology and its correlates with existing literature for hepatocellular carcinoma (HCC), cholangiocarcinoma (CCA) and hepatoblastoma (HB). Among additional factors, the literature reports dysfunction in the tricarboxylic acid metabolism, primarily for HB and HCC, and point mutations and signaling for CCA. All cases require further investigation of upstream and downstream events. All liver cancers reported dysfunction in the WNT/β-catenin and P13K/AKT/mTOR pathways as well as changes in FGFR. Metabolites of IHD1, IDH2, miRNA, purine, Q10, lipids, phosphatidylcholine, phosphatidylethanolamine, acylcarnitine, 2-HG and propionyl-CoA emerged as crucial and there was an attempt to elucidate the WNT/β-catenin and P13K/AKT/mTOR pathways metabolomically.
Semi-natural grasslands (SNGs) are an essential part of European cultural landscapes. They are an important habitat for many animal and plant species and offer a variety of ecological functions. Diverse plant communities have evolved over time depending on environmental and management factors in grasslands. These different plant communities offer multiple ecosystem services and also have an effect on the forage value of fodder for domestic livestock. However, with increasing intensification in agriculture and the loss of SNGs, the biodiversity of grasslands continues to decline. In this paper, we present a method to spatially classify plant communities in grasslands in order to identify and map plant communities and weed species that occur in a semi-natural meadow. For this, high-resolution multispectral remote sensing data were captured by an unmanned aerial vehicle (UAV) in regular intervals and classified by a convolutional neural network (CNN). As the study area, a heterogeneous semi-natural hay meadow with first- and second-growth vegetation was chosen. Botanical relevés of fixed plots were used as ground truth and independent test data. Accuracies up to 88% on these independent test data were achieved, showing the great potential of the usage of CNNs for plant community mapping in high-resolution UAV data for ecological and agricultural applications.
Advances in high-throughput DNA sequencing have propelled research into the human microbiome and its link to metabolic health. We explore microbiome analysis methods, specifically emphasizing metabolomics, how dietary choices impact the production of microbial metabolites, providing an overview of studies examining the connection between enterotypes and diet, and thus, improvement of personalized dietary recommendations. Acetate, propionate, and butyrate constitute more than 95% of the collective pool of short-chain fatty acids. Conflicting data on acetate’s effects may result from its dynamic signaling, which can vary depending on physiological conditions and metabolic phenotypes. Human studies suggest that propionate has overall anti-obesity effects due to its well-documented chemistry, cellular signaling mechanisms, and various clinical benefits. Butyrate, similar to propionate, has the ability to reduce obesity by stimulating the release of appetite-suppressing hormones and promoting the synthesis of leptin. Tryptophan affects systemic hormone secretion, with indole stimulating the release of GLP-1, which impacts insulin secretion, appetite suppression, and gastric emptying. Bile acids, synthesized from cholesterol in the liver and subsequently modified by gut bacteria, play an essential role in the digestion and absorption of dietary fats and fat-soluble vitamins, but they also interact directly with intestinal microbiota and their metabolites. One study using statistical methods identified primarily two groupings of enterotypes Bacteroides and Ruminococcus. The Prevotella-dominated enterotype, P-type, in humans correlates with vegetarians, high-fiber and carbohydrate-rich diets, and traditional diets. Conversely, individuals who consume diets rich in animal fats and proteins, typical in Western-style diets, often exhibit the Bacteroides-dominated, B-type, enterotype. The P-type showcases efficient hydrolytic enzymes for plant fiber degradation but has limited lipid and protein fermentation capacity. Conversely, the B-type features specialized enzymes tailored for the degradation of animal-derived carbohydrates and proteins, showcasing an enhanced saccharolytic and proteolytic potential. Generally, models excel at predictions but often struggle to fully elucidate why certain substances yield varied responses. These studies provide valuable insights into the potential for personalized dietary recommendations based on enterotypes
Die Autoren präsentieren einen innovativen Ansatz für Circular Economy (CE)-Strategien mit hohem Umweltpotenzial. Dieser Ansatz betont Verweigerung, Umdenken und Reduzieren, indem die Perspektive vom Verbraucher auf soziale Praktiken verschoben wird. Dabei wird Suffizienz als Schlüsselkonzept eingeführt, das entscheidend ist, um Umweltbelastungen durch CE zu reduzieren und die Transformation des Produktions- und Konsumsystems zu fördern. Die Autoren betonen, dass nachhaltige Kreislaufwirtschaft ohne Suffizienz nicht möglich ist.
Die Studie berichtet über einen Fall, in dem die Über-Verfügbarkeit durch das Konzept der Genügsamkeit ersetzt wurde. Die Autoren beobachten, wie Suffizienz in die Lebensstile der Teilnehmer integriert wird, insbesondere durch einen Farmboxing-Ansatz. Obwohl die Verallgemeinerung des Falls begrenzt ist, zeigt die Studie das Potenzial niedrigschwelliger Einführungen von Suffizienz, wie beispielsweise öffentlicher Raum für gärtnerische Aktivitäten.
Die Autoren betonen jedoch die Notwendigkeit weiterer empirischer Arbeit, um die Bedeutung von Suffizienz in verschiedenen sozialen Praktiken zu verstehen. Sie schlagen vor, dass der Zeitpunkt für solche Forschungen günstig ist, angesichts aktueller globaler Entwicklungen und der steigenden Nachfrage nach Strategien zur Ressourcenverringerung.
Die Studie identifiziert Herausforderungen, darunter unklare Faktoren, die nicht berücksichtigt wurden, wie die Rolle des sozialen Umfelds und die Übertragbarkeit der Ergebnisse auf andere Lebensbereiche. Die Autoren planen bereits eine Folgestudie mit quantitativen und qualitativen Analysen sowie Lebenszyklusanalysen.
Abschließend schlagen die Autoren vor, klare Definitionen für Wiederverwendung, Umdenken und Reduzierung zu entwickeln, basierend auf empirischen Daten und Beispielen sozialer Praktiken. Sie fordern auch dazu auf, Theorien sozialer Praktiken auf andere CE-Strategien anzuwenden, da soziale Praktiken nicht auf privaten Konsum beschränkt sind.
The BBI is a first step toward putting biodiversity conservation into practice in the OHC context. The results are consistent with studies related to nutrition However, the results also show that there is room for improvement and that there are further areas to be addressed. It is also clear that commercial kitchens currently have only limited room for maneuver. If OHC is to become more biodiversity-friendly, greater transparency is needed in terms of origin labels and species/variety identifiers, and a wide range of options will also be required in terms of procurement. That being the case, it is essential to focus on the entire value chain. Furthermore, in addition to the initial recommendations, much more knowledge is required about the impacts of farming methods and heritage varieties and species, as well as about the use of fish, other marine animals and game meat. In principle, however, the BBI can already be implemented in commercial kitchens by identifying recipe optimizations that kitchens can feasibly implement, that align with their budgets, and that maintain acceptance among patrons. In addition, this approach has the potential to be integrated into the assessment framework of the NAHGAST calculator, making it readily accessible and free for OHC facilities to use. In the OHC context in particular, this could be leveraged to drive sustainable change in the food system.
Leftovers lovers vs. haters: A latent class analysis on dinner leftover management behaviours
(2023)
Die Studie untersucht die Heterogenität im Umgang mit Speiseresten in Haushalten, insbesondere unter Verwendung von Mahlzeitensets mit angepassten Portions- und Zutatengrößen. Durch eine latenten Klassenanalyse werden Verbrauchersegmente identifiziert, wobei die positive Einstellung zu Essensresten und bewusster Umgang damit untersucht werden. Die Studie analysiert auch die Auswirkungen von Emotionen, persönlichen Normen, Intentionen und Essensbeschaffungsroutinen auf die Zugehörigkeit zu einem Resteverwertungssegment. Daten von 868 Haushalten aus sechs Ländern zeigen fünf Verbrauchersegmente mit Unterschieden in der Menge der Essensreste. Mahlzeitensets haben heterogene Auswirkungen, indem sie in einigen Segmenten die Menge der Essensreste verringern, in anderen jedoch nicht. Die Ergebnisse bieten neue Erkenntnisse über die Vielfalt im Umgang mit Speiseresten und liefern Implikationen für Theorie und Politik zur Reduzierung von Lebensmittelverschwendung im Haushalt.
In a protein reduction feeding trial (Study 1) on a commercial broiler farm in northern Germany, it was attempted to be shown that research results from station tests on protein reduction can be transferred to agricultural practice. In a second study, the limits of the N reduction were tested in a research facility. In Study 1, commercial standard feeds were fed to the control group (variant 1:210,000 animals; n = 5 barns). In the test group (variant 2:210,000 animals; n = 5 barns), the weighted mean crude protein (CP) content was moderately reduced by 0.3%. The nitrogen reduction in the feed did not affect performance (feed intake (FA), daily gain (DG), feed conversion (FCR)), but nitrogen conversion rate increased from approx. 61% to approx. 63%. The solid litter weight was reduced by 12% and nitrogen excretion by 9% (p < 0.05). Significantly healthier footpads were due to lower water intake (−4%; p < 0.05) and a numerically drier bedding. In Study 2, responses of treatments (1250 broiler per variant; n = 5) showed that sharper N-lowering (−1.5% CP; weighted average) did not impair performance either, but N-conversion improved and N-excretions decreased significantly. Converted to a protein reduction of one percentage point, the N excretions were able to be reduced by 22% in Study 1 and 18% in Study 2. Feeding trials in the commercial sector, such as the present Study 1, should convince feed mills and farmers to allow the latest scientific results to be used directly and comprehensively in commercial ration design.
Duckweed is gaining attention in animal nutrition and is considered as a potential alternative protein source for broiler chickens. In order to evaluate the nutritional value of duckweed, three individual batches were investigated. They consisted of a mixture of Lemna minuta and Lemna minor (A, 17.5% crude protein), Spirodela polyrhiza (B, 24.6% crude protein) and Lemna obscura (C, 37.0% crude protein). Treatment diets contained 50% batch A, 50% batch B, and 25, 50 and 75% of batch C. All diets were fed to broiler chickens (Ross 308) from an age of 21 to 27 days. Diets with a share of 50 and 75% of batch C led to decreased feed intake (109.3 and 74.9 g/day, respectively) compared to the control. Standardized ileal digestibility of crude protein and amino acids differed significantly between duckweed batches, at values for methionine between 49.9 and 90.4%. For all amino acids, batch A consistently had the lowest and batch C the highest digestibility. Batches had different tannin contents of 2943, 2890 and 303 mg/kg for batches A, B and C, respectively. The apparent ileal digestibility of phosphorus differed significantly between all batches (50.8–78.9%). Duckweed can be used as a protein feed for broiler chickens. However, a defined and stable biomass composition optimized for the requirements of broiler chickens is needed.
The present study aims to compare the effects of maternal and offspring treatment with 25-hydroxycholecalciferol (25-OHD3) and vitamin D3 on vitamin D status, mineral homoeostasis, bone metabolism and locomotion in the offspring. Either vitamin D3 (50 μg/kg diet) or 25-OHD3 (50 μg/kg diet) was supplemented to the gestation and lactation diets of 49 multiparous sows and/or to the diets of their growing offspring. Treatment of the sows did not affect plasma concentrations of 25-OHD3 of the offspring. Pigs fed 25-OHD3 had higher plasma concentrations of 25-OHD3 than pigs that received vitamin D3 during rearing and fattening. However, neither plasma concentrations of calcium, phosphate and bone markers during the observation period nor bone ash and bone mineral density at slaughter were clearly affected by the treatment. Maternal and offspring treatment with 25-OHD3 instead of vitamin D3 resulted in a slight reduction in the prevalence of leg swelling. In addition, more pigs walked with even steps and normal stride length. Further studies are needed to test whether the slight effects observed in the present experiment are reproducible and of relevance for animal health and welfare. In that case, the underlying mechanisms should be revealed in order to take advantage of potentially beneficial influences especially under certain feeding regimes.
Background
The aim of this qualitative study was to identify a practice level model that could explain a sustained change in nutritional behavior.
Methods
The study used three data inputs from four interviewees, one merged input from a married couple, as narrative interviews. The interviews were analyzed using grounded theory.
Results
Coexistence of a certain suffering and a triggering episode lead to the decision to change nutritional life-style by all interviewed. Maintenance of the self-determined newly learned nutritional behavior was supported by subject-related intrinsic motivation, the ability to reflect, and a low expectation of success from the behavioral change. Environment-related factors were identified as support from life-partner and peers. Subjects reported that the sustained nutritional behavior change impacted their holistic health through subject-perceived improved life quality, increase in the number of social contacts, and a change in personal attitudes and perception. The analysis remains limited, and at best hypothesis generating, in that only three data inputs from four interviewees were used.
Conclusion
In this hypothesis-generating narrative interview study of four study subjects, volition, personal decision making, and long-term motivation (though not external determination) seemed to sustain a change in newly learned nutritional behavior.
Farmland bird populations are in a deep crisis across Europe. Agri-environment schemes (AES) were implemented by the European Union to stop and reverse the general decline of biodiversity in agricultural landscapes. In Germany, flower strips are one of the most common AES. Establishing high-quality perennial wildflower strips (WFS) with species-rich native forb mixtures from regional seed propagation is a recent approach, for which the effectiveness for birds has not yet been sufficiently studied. We surveyed breeding birds and vegetation on 40 arable fields with WFS (20 with single and 20 with aggregated WFS) and 20 arable fields lacking WFS as controls across Saxony-Anhalt (Germany). Additionally, vegetation composition, WFS quantity and landscape structure (e.g. distance to nearest woody element) were considered in our analyses. All WFS were established with species-rich native seed mixtures (30 forbs) in agricultural practice as AES. Arable fields with WFS had a higher species richness and territory density of birds than controls, confirming the effectiveness of this AES. A forb-rich vegetation was the main driver promoting birds. Flower strip quantity at the landscape level had positive effects only on bird densities, but also single WFS achieved benefits. A short distance from WFS to woody elements increased total bird species richness. However, the density of farmland birds, which are target species of these AES, were negatively affected by the proximity and proportion of woody elements in the vicinity. The effect of the proportion of non-intensively used open habitats and overall habitat richness was unexpectedly low in the otherwise intensively farmed landscape. Species-rich perennial WFS significantly promoted breeding birds. Successful establishment of WFS, resulting in high-quality habitats, a high flower strip quantity as well as implementation in open landscapes were shown to maximise the effectiveness for restoring declining and AES target farmland birds.
Adventitious root (AR) formation is the basis of vegetative propagation in rose, be it via stem cuttings or via stenting. During this process, wounding plays a pivotal role since cell reprogramming takes place at the tissue adjacent to the wound. We investigated the effects of wounding on AR formation on leafy single-node stem cuttings of the rose rootstock R. canina ‘Pfänder’ (codes R02-3 and R02-6) and the cut rose cultivar Rosa ‘Tan09283’ (Registration name ‘Beluga’). Laser wounding treatments were based on the assisted removal of tissue layers located in the bark. The positioning of wounding was studied based on two marking directions: along the cutting base (strip pattern) and around the cutting base (ring pattern). Additionally, the effects of external supply of indole-butyric acid (IBA 1 mg L-1) on rootingwere analyzed. Results showedthat inorder toremovespecific tissue layers, the calculation of the laser energy density (J cm-2) in terms of cutting diameter was necessary. Interestingly, the application of energy densities from 2.5 J cm-2 up to approximately 8.5 J cm-2 were sufficient to expose the tissue layers of epidermis up to regions of phloem. Regarding AR formation for R. canina ‘Pfänder’, characterized by a low rooting response, an increase in the rooting percentage was registered when the laser treatment eliminated the tissue up to phloem proximities. Analysis of the nodal position showed that bud location was a preferential place for AR formation independently of wounding treatment. In case of Rosa ‘Tan09283’, laser treatments did not reduce its high rooting capacity, but an apparent reduction in rooting quality due to an investment in tissue healing was observed when wounding reached deeper layers such as parenchyma and sclerenchyma. Results also showeda strongARformation directly fromwounded regions in case of Rosa ‘Tan09283’ specifically when the woundwas located below the axillary bud. In conclusion, wounding by assisted-elimination of layers by laser can induce positive effects on AR formation of single-node stemcuttings of the rose if energy applied is able to expose phloemproximities,a longitudinalorientation, and relative position to the axillary bud are considered.
Background
Spinach is a nitrogen (N) demanding crop with a weekly N uptake of up to 60 kg ha–1. Consequently, a high N supply is required, which can temporarily lead to high quantities of nitrate (NO3–) being at risk of leaching.
Aims
The objective of this study was to develop a N fertilization approach to reduce the risk of NO3– leaching in field-grown spinach production without adversely affecting crop yield and quality at an early and late harvest stage.
Methods
Ten fertilization trials were conducted to compare different base fertilization rates and splits of top dressings. For top dressings, granulated fertilizers or foliar sprays were used. In a further treatment, N supply was reduced by withholding the second top dressing of 50–70 kg ha−1.
Results
Nitrate concentration at risk of leaching was considerably reduced by decreasing the base fertilizer rate as well as by splitting the top dressing. However, at an early harvest stage, total aboveground dry mass was reduced by, on average, 6% by these measures across all seasons. In contrast, at a later harvest stage, spinach was less affected by the fertilizer schedule. Urea foliar sprays proved to be insufficient in promoting plant growth and caused leaf necrosis. A reduced N supply led to impaired plant growth and yellowish leaves in both spring and winter.
Conclusions
Base N fertilization of spinach is only required in spring, but not in other seasons. Despite slight yield reduction, the top dressing should be split to reduce the risk of NO3− leaching after an early harvest.
In open-field vegetable production, high quantities of soil mineral nitrogen (Nmin) and N-rich crop residues often remain in the field at harvest. After the harvest of crops in autumn, this N can lead to considerable nitrate (NO3−) losses during the subsequent winter leaching period. In four field trials, different tillage depths (3–4, 10, 30 cm) and dates (early autumn, late autumn, early spring) were investigated to reduce N losses after growing spinach in the autumn. In a further treatment, the nitrification inhibitor 3,4-Dimethylpyrazole phosphate (DMPP) was directly applied to the crop residues. Potential N losses were calculated by a balance sheet approach based on Nmin concentration (0–90 cm), measured N mineralization and N uptake by catch crops. By postponing the tillage date from early to late autumn or spring, resprouting spinach stubbles acted as a catch crop, reducing N losses by up to 61 kg ha−1. However, if the spinach biomass collapsed, the N losses increased by up to 33 kg ha−1 even without tillage. The application of DMPP as well as the tillage depth were less effective. Overall, postponing tillage to spring seems to be the most promising approach for reducing N losses during the off-season.
Dieser Artikel befasst sich mit dem bundesweiten Niveau der Treibhausgas (THG)-Emissionen und des Ressourcenverbrauchs in der deutschen Gemeinschaftsverpflegung im Segment "Business" und deren Einsparpotenziale durch verschiedene Szenarien der ungestützten und gestützten Rezeptüberarbeitung. Unter "ungestützt" verstehen wir in dieser Arbeit die intuitive Optimierung von Rezepten durch die Mitarbeiter von Betrieben der Gemeinschaftsverpflegung. Die "unterstützten" Ansätze mussten dagegen bestimmte Zielvorgaben erfüllen, zum Beispiel der Deutschen Gesellschaft für Ernährung; engl. Deutschen Gesellschaft für Ernährung oder das nachhaltige Niveau. Konkret Konkret wird getestet, wie sich (A) eine ungestützte Rezeptüberarbeitung, (B) eine Rezeptüberarbeitung auf Basis von Ernährungsempfehlungen und (C) eine Rezeptüberarbeitung mit wissenschaftlicher Begleitung die Umweltauswirkungen eines Gerichtes beeinflussen. Als methodischer Rahmen diente eine Online-Befragung von Unternehmen der Gemeinschaftsverpflegung sowie eine Szenarioanalyse auf Menüebene und auf nationaler Ebene durchgeführt. Die Ergebnisse basieren zum einen auf empirischen Daten und zum anderen auf Hochrechnungen. Die Ergebnisse zeigen, dass die die bundesweite Umsetzung der Rezepturüberarbeitung nach wissenschaftlichen Vorgaben - wie konkrete Zielvorgaben für die THG Emissionen pro Portion - bis zu 44% des Ressourcenverbrauchs in der deutschen Betriebsgastronomie einsparen kann (das entspricht 3,4 Millionen Tonnen Ressourcen pro Jahr) und bis zu 40 % der THG-Emissionen (0,6 Millionen Tonnen THG-Emissionen pro Jahr) einsparen.