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- ItemThinning efficacy of metamitron on young 'RoHo 3615' (Evelina®) apple(Amsterdam [u.a.] : Elsevier Science, 2020) Penzel, Martin; Kröling, ChristianTo achieve a high quantity of premium class fruit, chemical thinning is an important component of crop load management in apples. For this purpose, the triazine-type photosynthetic inhibitor metamitron was registered for fruit thinning in Germany. Frequent studies demonstrated consistent thinning effects of metamitron on trees of different apple and pear cultivars. In the present study, the efficacy of metamitron applied at a low concentration (165 g ha−1) was investigated in 2016 and 2017 on young 'RoHo3615' apple trees, planted in 2014. The highest fruit set reduction was achieved when metamitron was applied twice. Single application, in contrast, led to variable results and pointed out the strong dependence of the thinning efficacy of metamitron on favourable weather conditions. Adding citric acid or the growth regulator prohexadione-Ca in combination with ammonium sulphate did not affect the thinning efficacy of metamitron. The fruit quality was high in any treatment and no effects of thinning treatment on fruit colouration or percentage of skin russeting were observed. Consequently, metamitron is an effective fruit thinning agent for young apple trees, which can be additionally used in combination with the mentioned substances, while maintaining a high fruit quality
- ItemParticulate matter emissions during field application of poultry manure - The influence of moisture content and treatment(Amsterdam [u.a.] : Elsevier Science, 2021) Kabelitz, Tina; Biniasch, Oliver; Ammon, Christian; Nübel, Ulrich; Thiel, Nadine; Janke, David; Swaminathan, Senthilathiban; Funk, Roger; Münch, Steffen; Rösler, Uwe; Siller, Paul; Amon, Barbara; Aarnink, André J. A.; Amon, ThomasAlong with industry and transportation, agriculture is one of the main sources of primary particulate matter (PM) emissions worldwide. Bioaerosol formation and PM release during livestock manure field application and the associated threats to environmental and human health are rarely investigated. In the temperate climate zone, field fertilization with manure seasonally contributes to local PM air pollution regularly twice per year (spring and autumn). Measurements in a wind tunnel, in the field and computational fluid dynamics (CFD) simulations were performed to analyze PM aerosolization during poultry manure application and the influence of manure moisture content and treatment. A positive correlation between manure dry matter content (DM) and PM release was observed. Therefore, treatments strongly increasing the DM of poultry manure should be avoided. However, high manure DM led to reduced microbial abundance and, therefore, to a lower risk of environmental pathogen dispersion. Considering the findings of PM and microbial measurements, the optimal poultry manure DM range for field fertilization was identified as 50–70%. Maximum PM10 concentrations of approx. 10 mg per m3 of air were measured during the spreading of dried manure (DM 80%), a concentration that is classified as strongly harmful. The modeling of PM aerosolization processes indicated a low health risk beyond a distance of 400 m from the manure application source. The detailed knowledge about PM aerosolization during manure field application was improved with this study, enabling manure management optimization for lower PM aerosolization and pathogenic release into the environment.
- ItemVisible-NIR ‘point’ spectroscopy in postharvest fruit and vegetable assessment: The science behind three decades of commercial use(Amsterdam [u.a.] : Elsevier Science, 2020) Walsh, Kerry B.; Blasco, José; Zude-Sasse, Manuela; Sun, XudongThe application of visible (Vis; 400–750 nm) and near infrared red (NIR; 750–2500 nm) region spectroscopy to assess fruit and vegetables is reviewed in context of ‘point’ spectroscopy, as opposed to multi- or hyperspectral imaging. Vis spectroscopy targets colour assessment and pigment analysis, while NIR spectroscopy has been applied to assessment of macro constituents (principally water) in fresh produce in commercial practice, and a wide range of attributes in the scientific literature. This review focusses to key issues relevant to the widespread implementation of Vis-NIR technology in the fruit sector. A background to the concepts and technology involved in the use of Vis-NIR spectroscopy is provided and instrumentation for in-field and in-line applications, which has been available for two and three decades, respectively, is described. A review of scientific effort is made for the period 2015 - February 2020, in terms of the application areas, instrumentation, chemometric methods and validation procedures, and this work is critiqued through comparison to techniques in commercial use, with focus to wavelength region, optical geometry, experimental design, and validation procedures. Recommendations for future research activity in this area are made, e.g., application development with consideration of the distribution of the attribute of interest in the product and the matching of optically sampled and reference method sampled volume; instrumentation comparisons with consideration of repeatability, optimum optical geometry and wavelength range). Recommendations are also made for reporting requirements, viz. description of the application, the reference method, the composition of calibration and test populations, chemometric reporting and benchmarking to a known instrument/method, with the aim of maximising useful conclusions from the extensive work being done around the world.
- ItemThe impact of atmospheric boundary layer, opening configuration and presence of animals on the ventilation of a cattle barn(Amsterdam [u.a.] : Elsevier Science, 2020) Nosek, Štěpán; Kluková, Zuzana; Jakubcová, Michaela; Yi, Qianying; Janke, David; Demeyer, Peter; Jaňour, ZbyněkNaturally ventilated livestock buildings (NVLB) represent one of the most significant sources of ammonia emissions. However, even the dispersion of passive gas in an NVLB is still not well understood. In this paper, we present a detailed investigation of passive pollutant dispersion in a model of a cattle barn using the wind tunnel experiment method. We simulated the pollution of the barn by a ground-level planar source. We used the time-resolved particle image velocimetry (TR-PIV) and the fast flame ionisation detector (FFID) to study the flow and dispersion processes at high spatial and temporal resolution. We employed the Proper Orthogonal Decomposition (POD) and Oscillating Patterns Decomposition (OPD) methods to detect the coherent structures of the flow. The results show that the type of atmospheric boundary layer (ABL) and sidewall opening height have a significant impact on the pollutant dispersion in the barn, while the presence of animals and doors openings are insignificant under conditions of winds perpendicular to the sidewall openings. We found that the dynamic coherent structures, developed by the Kelvin-Helmholtz instability, contribute to the pollutant transport in the barn. We demonstrate that in any of the studied cases the pollutant was not well mixed within the barn and that a significant underestimation (up to by a factor 3) of the barn ventilation might be obtained using, e.g. tracer gas method. © 2020 The Authors
- ItemWhat makes soil landscape robust? Landscape sensitivity towards land use changes in a Swiss southern Alpine valley(Amsterdam [u.a.] : Elsevier Science, 2022) Bettoni, Manuele; Maerker, Michael; Sacchi, Roberto; Bosino, Alberto; Conedera, Marco; Simoncelli, Laura; Vogel, SebastianLandscape sensitivity is a concept referring to the likelihood that changes in land use may affect in an irreversible way physical and chemical soil properties of the concerned landscape. The objective of this study is to quantitatively assess the sensitivity of the southern Alpine soil landscape regarding land use change-induced perturbations. Alpine soil landscapes can be considered as particularly sensitive to land use changes because their effects tend to be enhanced by frequent extreme climatic and topographic conditions as well as intense geomorphologic activity. In detail, the following soil key properties for soil vulnerability were analysed: (i) soil texture, (ii) bulk density, (iii) soil organic carbon (SOC), (iv) saturated hydraulic conductivity (Ksat), (v) aggregate stability and (vi) soil water repellency (SWR). The study area is characterized by a steep, east-west oriented valley, strongly anthropized in the last centuries followed by a progressive abandonment. This area is particularly suitable due to constant lithological conditions, extreme topographic and climatic conditions as well as historic land use changes. The analysis of land use change effects on soil properties were performed through a linear mixed model approach due to the nested structure of the data. Our results show a generally high stability of the assessed soils in terms of aggregate stability and noteworthy thick soils. The former is remarkable, since aggregate stability, which is commonly used for detecting land use-induced changes in soil erosion susceptibility, was always comparably high irrespective of land use. The stability of the soils is mainly related to a high amount of soil organic matter favouring the formation of stable soil aggregates, decreasing soil erodibility and hence, reducing soil loss by erosion. However, the most sensitive soil property to land use change was SWR that is partly influenced by the amount of soil organic carbon and probably by the quality and composition of SOM.
- ItemCold atmospheric pressure plasma and low energy electron beam as alternative nonthermal decontamination technologies for dry food surfaces: A review(Amsterdam [u.a.] : Elsevier Science, 2018) Hertwig, Christian; Meneses, Nicolas; Mathys, AlexanderBackground: Dry food products are often highly contaminated, and dry stress-resistant microorganisms, such as certain types of Salmonella and bacterial spores, can be still viable and multiply if the product is incorporated into high moisture food products or rehydrated. Traditional technologies for the decontamination of these products have certain limitations and drawbacks, such as alterations of product quality, environmental impacts, carcinogenic potential and/or lower consumer acceptance. Cold atmospheric pressure plasma (CAPP) and low energy electron beam (LEEB) are two promising innovative technologies for microbial inactivation on dry food surfaces, which have shown potential to solve these certain limitations. Scope and approach: This review critically summarizes recent studies on the decontamination of dry food surfaces by CAPP and LEEB. Furthermore, proposed inactivation mechanisms, product-process interactions, current limitations and upscaling potential, as well as future trends and research needs for both emerging technologies, are discussed. Key findings and conclusions: CAPP and LEEB are nonthermal technologies with a high potential for the gentle decontamination of dry food surfaces. Both technologies have similarities in their inactivation mechanisms. Due to the limited penetration depth of both technologies, product-process interactions can be minimized by maintaining product quality. A first demonstrator with Technology Readiness Level (TRL) 7 for LEEB has already been introduced into the food industry for the decontamination of herbs and spices. Compared with LEEB, CAPP is at the advanced development stage with TRL 5, for which further work is essential to design systems that are scalable to industrial requirements. © 2018 The Authors
- ItemComparison of ammonia emissions related to nitrogen use efficiency of livestock production in Europe(Amsterdam [u.a.] : Elsevier Science, 2019) Groenestein, C.M.; Hutchings, N.J.; Haenel, H.D.; Amon, B.; Menzi, H.; Mikkelsen, M.H.; Misselbrook, T.H.; van Bruggen, C.; Kupper, T.; Webb, J.The increasing global demand for food and the environmental effects of reactive nitrogen losses in the food production chain, increase the need for efficient use of nitrogen (N). Of N harvested in agricultural plant products, 80% is used to feed livestock. Because the largest atmospheric loss of reactive nitrogen from livestock production systems is ammonia (NH3), the focus of this paper is on N lost as NH3 during the production of animal protein. The focus of this paper is to understand the key factors explaining differences in Nitrogen Use Efficiency (NUE) of animal production among various European countries. Therefore we developed a conceptual framework to describe the NUE defined as the amount of animal-protein N per N in feed and NH3–N losses in the production of milk, beef, pork, chicken meat and eggs in The Netherlands, Switzerland, United Kingdom, Germany, Austria and Denmark. The framework describes how manure management and animal-related parameters (feed, metabolism) relate to NH3 emissions and NUE. The results showed that the animal product with the lowest NUE had the largest NH3 emissions and vice versa, which agrees with the reciprocal relationship between NUE and NH3 within the conceptual framework. Across animal products for the countries considered, about 20% of the N in feed is lost as NH3. The significant smallest proportion (12%) of NH3–N per unit of Nfeed is from chicken production. The proportions for other products are 17%, 19%, 20% and 22% for milk, pork, eggs and beef respectively. These differences were not significantly different due to the differences among countries. For all countries, NUE was lowest for beef and highest for chicken. The production of 1 kg N in beef required about 5 kg N in feed, of which 1 kg N was lost as NH3–N. For the production of 1 kg N in chicken meat, 2 kg N in feed was required and 0.2 kg was lost as NH3. The production of 1 kg N in milk required 4 kg N in feed with 0.6 kg NH3–N loss, the same as pork and eggs, but those needed 3 and 3.5 kg N in feed per kg N in product respectively. Except for beef, the differences among these European countries were mainly caused by differences in manure management practices and their emission factors, rather than by animal-related factors including feed and digestibility influencing the excreted amount of ammoniacal N (TAN). For beef, both aspects caused important differences. Based on the results, we encourage the expression of N losses as per N in feed or per N in product, in addition to per animal place, when comparing production efficiency and NUE. We consider that disaggregating emission factors into a diet/animal effect and a manure management effect would improve the basis for comparing national NH3 emission inventories. © 2018 The Authors
- ItemModelling the effect of feeding management on greenhouse gas and nitrogen emissions in cattle farming systems(Amsterdam [u.a.] : Elsevier Science, 2021) Ouatahar, Latifa; Bannink, André; Lanigan, Gary; Amon, BarbaraFeed management decisions are an important element of managing greenhouse gas (GHG) and nitrogen (N) emissions in livestock farming systems. This review aims to a) discuss the impact of feed management practices on emissions in beef and dairy production systems and b) assess different modelling approaches used for quantifying the impact of these abatement measures at different stages of the feed and manure management chain. Statistical and empirical models are well-suited for practical applications when evaluating mitigation strategies, such as GHG calculator tools for farmers and for inventory purposes. Process-based simulation models are more likely to provide insights into the impact of biotic and abiotic drivers on GHG and N emissions. These models are based on equations which mathematically describe processes such as fermentation, aerobic and anaerobic respiration, denitrification, etc. and require a greater number of input parameters. Ultimately, the modelling approach used will be determined by a) the activity input data available, b) the temporal and spatial resolution required and c) the suite of emissions being studied. Simulation models are likely candidates to be able to better explain variation in on-farm GHG and N emissions, and predict with a higher accuracy for a specific mitigation measure under defined farming conditions, due to the fact that they better represent the underlying mechanisms causal for emissions. Integrated farm system models often make use of rather generic values or empirical models to quantify individual emissions sources, whereas combining a whole set of process-based models (or their results) that simulates the variation in GHG and N emissions and the associated whole farm budget has not been used. The latter represents a valuable approach to delineate underlying processes and their drivers within the system and to evaluate the integral effect on GHG emissions with different mitigation options.
- ItemValidation study for measuring absorption and reduced scattering coefficients by means of laser-induced backscattering imaging(Amsterdam [u.a.] : Elsevier Science, 2019) Zude-Sasse, Manuela; Hashim, Norhashila; Hass, Roland; Polley, Nabarun; Regen, ChristianDecoupling of optical properties appears challenging, but vital to get better insight of the relationship between light and fruit attributes. In this study, nine solid phantoms capturing the ranges of absorption (μa) and reduced scattering (μs’) coefficients in fruit were analysed non-destructively using laser-induced backscattering imaging (LLBI) at 1060 nm. Data analysis of LLBI was carried out on the diffuse reflectance, attenuation profile obtained by means of Farrell's diffusion theory either calculating μa [cm−1] and μs’ [cm−1] in one fitting step or fitting only one optical variable and providing the other one from a destructive analysis. The nondestructive approach was approved when calculating one unknown coefficient non-destructively, while no ability of the method was found to analysis both, μa and μs’, non-destructively. Setting μs’ according to destructive photon density wave (PDW) spectroscopy and fitting μa resulted in root mean square error (rmse) of 18.7% in comparison to fitting μs’ resulting in rmse of 2.6%, pointing to decreased measuring uncertainty, when the highly variable μa was known. The approach was tested on European pear, utilizing destructive PDW spectroscopy for setting one variable, while LLBI was applied for calculating the remaining coefficient. Results indicated that the optical properties of pear obtained from PDW spectroscopy as well as LLBI changed concurrently in correspondence to water content mainly. A destructive batch-wise analysis of μs’ and online analysis of μa may be considered in future developments for improved fruit sorting results, when considering fruit with high variability of μs’. © 2019 The Authors
- ItemGreenhouse gas emissions from broiler manure treatment options are lowest in well-managed biogas production(Amsterdam [u.a.] : Elsevier Science, 2020) Kreidenweis, Ulrich; Breier, Jannes; Herrmann, Christiane; Libra, Judy; Prochnow, AnnetteThe production of broiler meat has increased significantly in the last decades in Germany and worldwide, and is projected to increase further in the future. As the number of animals raised increases, so too does the amount of manure produced. The identification of manure treatment options that cause low greenhouse gas emissions becomes ever more important. This study compares four treatment options for broiler manure followed by field spreading: storage before distribution, composting, anaerobic digestion in a biogas plant and production of biochar. For these options potential direct and indirect greenhouse gas emissions were assessed for the situation in Germany. Previous analyses have shown that greenhouse gas balances of manure management are often strongly influenced by a small number of processes. Therefore, in this study major processes were represented with several variants and the sensitivity of model results to different management decisions and uncertain parameters was assessed. In doing so, correlations between processes were considered, in which higher emissions earlier on in the process chain reduce emissions later. The results show that biogas production from broiler manure leads to the lowest greenhouse gas emissions in most of the analysed cases, mainly due to the emission savings related to the substitution of mineral fertilizers and the production of electricity. Pyrolysis of the manure and subsequent field spreading as a soil amendment can lead to similarly low emissions due to the long residence time of the biochar, and may even be the better option than poorly managed biogas production. Composting is the treatment option resulting in highest emissions of greenhouse gases, due to high ammonia volatilization, and is likely worse than untreated storage in this respect. These results are relatively insensitive to the length of transport required for field spreading, but high uncertainties are associated with the use of emission factors.