Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

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    The European Journal of Soil Biology: A catalyst for soil biodiversity research
    Geisen, S.A. ; Hartmann, M. ; Tebbe, Christoph C. - \ 2021
    European Journal of Soil Biology 102 (2021). - ISSN 1164-5563
    Adapting Yet Not Adopting? Conservation Agriculture in Central Malawi
    Bouwman, T.I. ; Andersson, J.A. ; Giller, K.E. - \ 2021
    Agriculture, Ecosystems and Environment 307 (2021). - ISSN 0167-8809 - p. 1 - 1.
    Conservation Agriculture (CA) has been widely promoted as a pathway to sustainably intensify agriculture in sub-Saharan Africa (SSA). Yet despite decades of promotion, CA uptake in SSA remains sparse with only few analyses of its impacts on farming and rural livelihoods. This study, which focuses on areas in Central Malawi considered to have a relatively high uptake of CA, uses analyses of satellite images, field observations, interviews with farmers, extension workers and other people involved in CA promotion, as well as a household survey, to
    investigate how CA has been adapted. We find that the three CA principles – (1) continuous minimum tillage, e.g. no-ridging, (2) permanent ground cover, and (3) crop rotation/intercropping – were not practiced as intended.
    First, one-third of non-ridged land was tilled during the growing season, and half was again ridged in the following season. Second, unless crop residues were added, the soil’s surface of non-ridged plots was usually bare at planting, causing weed control problems, and an increased risk of erosion. Most farmers added large volumes of crop residues to their non-ridged plots. They collected these from the surrounding fields, but this practice severely restricted the size of these plots. Third, crop rotation/intercropping was practiced less when farmers
    stopped ridging. Thus overall, very few farmers practised all of the three CA principles simultaneously. CA promotion appeared to only increase yields on plots where mulch was added, but this practice is not scalable. CA promotiondoes not seem to have provided substantial benefits for overall farm productivity, labour-savings or soil conservation.
    Urbanization: an increasing source of multiple pollutants to rivers in the 21st century
    Strokal, Maryna ; Bai, Zhaohai ; Franssen, Wietse ; Hofstra, Nynke ; Koelmans, Bart ; Ludwig, Fulco ; Ma, Lin ; Puijenbroek, Peter van; Spanier, Emiel ; Vermeulen, Lucie C. ; Vliet, Michelle T.H. van; Wijnen, Jikke van; Kroeze, Carolien - \ 2021
    Wageningen University & Research
    Africa - World - Scenarios - Rivers - Pollutants - Urban areas
    In this research, we quantify combined point-source inputs of nutrients, microplastics, a chemical (triclosan) and a pathogen (Cryptosporidium) to 10,226 rivers in 2010, 2050 and 2100, and show how pollutants are related. In the future, 80% of the global population could be living in urbanized areas where waters are polluted with multiple pollutants. We could formulate scenarios where future water pollution from growing cities is avoided by advanced waste water treatment in many world regions, but not in Africa.
    Governance prospects for maritime spatial planning in the tropical atlantic compared to EU case studies
    Guerreiro, José ; Carvalho, Ana ; Casimiro, Daniela ; Bonnin, Marie ; Calado, Helena ; Toonen, Hilde ; Fotso, Philippe ; Ly, Ibrahima ; Silva, Osvaldina ; Silva, Solange Teles da - \ 2021
    Marine Policy 123 (2021). - ISSN 0308-597X
    Institutional framework - Legal framework - Maritime governance - Maritime spatial planning - Tropical Atlantic

    Maritime spatial planning (MSP) is a governance approach that has been applauded for its promise to reconcile human uses and conservation, and is now widely implemented in member states of the European Union (EU), as well as in other countries in the Global North, like Canada, the United States and Australia. Five years ago, very few countries in the Global South seemed to be engaged in MSP. The Atlantic Ocean assumes the status of a major ecosystem and has geopolitical importance in the context of EU and is even more strengthened by the long-term political cooperation with the Tropical Atlantic countries regarding maritime affairs. The PADDLE project (EU RISE) aims to assess, in a north-south context, precisely how countries on the “Atlantic Boarder”, namely Senegal, Cape Verde and Brazil, encompass this trend towards MSP within their legal, institutional and political frameworks, following blue economy options and blue growth strategies. This contribution is an updated output of an international PADDLE project expert assessment, held in Brazil in February 2019, following two years of research. It intends to summarize the main conclusions on the state of the art and MSP prospects in the Tropical Atlantic, also referring to the ongoing MSP process in several EU countries. Political, legal and institutional frameworks enhancing MSP were presented and future trends for tropical MSP governance discussed.

    DNA barcoding of mosquitoes collected through a nationwide survey in 2011 and 2012 in Malawi, Southeast Africa
    Maekawa, Yoshihide ; Pemba, Dylo ; Kumala, Justin ; Gowelo, Steve ; Higa, Yukiko ; Futami, Kyoko ; Sawabe, Kyoko ; Tsuda, Yoshio - \ 2021
    Acta Tropica 213 (2021). - ISSN 0001-706X
    COI - GenBank - mosquitoes - neighbor-joining - phylogenetics - taxonomy

    We conducted a nationwide survey of mosquito distribution in Malawi from November 2011 to April 2012, and from July to September 2012. Using dried specimens of mosquito adults collected during the survey, we analyzed their cytochrome c oxidase subunit I (COI) gene sequences, prepared specimens, and registered the genetic information (658 bp) of 144 individuals belonging to 51 species of 10 genera in GenBank. Using the obtained genetic information, we analyzed the degree of intraspecific variation and investigated the various species from morphological and genetic perspectives. Moreover, we conducted phylogenetic analysis of the medically important species distributed from Africa to Asia and explored their geographical differentiation. Results showed that individuals morphologically classified as Culex univittatus complex included a individual of Cx. perexiguus which, to date, have not been reported in southern Africa. Furthermore, Mansonia uniformis, distributed in Africa and Asia, was revealed to belong to genetically distinct populations, with observed morphological differences of the samples suggesting that they are separate species. The results of genetic analysis further suggested that Cx. ethiopicus is not a synonym of Cx. bitaeniorhynchus, but that it is an independent species; although, in this study, the only definite morphological difference observed was in the shape of the wing scales. Further morphological and genetic investigation of individuals of these species, including larvae, is highly recommended.

    The impact of mussel seed fishery on the dynamics of wild subtidal mussel beds in the western Wadden Sea, The Netherlands
    Smaal, A.C. ; Craeymeersch, J.A. ; Stralen, M.R. van - \ 2021
    Journal of Sea Research 167 (2021). - ISSN 1385-1101
    Beyond baci-design - Fishery - Mussel stocks - Time series

    For the cultivation of mussels, wild stocks of juveniles are harvested to collect mussel seed as starting material for the culture. These wild stocks are found in the sublittoral western Wadden Sea (NL). After summer spat fall, fisheries in Autumn on newly formed beds is carried out in areas that have the risk of washing away due to storms, or are vulnerable for starfish predation. These wild beds are considered as relatively unstable. On remaining more stable wild beds, seed fishery is carried out in next Spring. As the Wadden Sea is a nature conservation area, mussel seed fisheries is only allowed if no negative impacts on the nature management objectives can be expected. Seed fishery impacts were addressed in an extensive study including effects on sediment composition, macrobenthos and epifauna. In this paper we describe the effects of mussel seed fisheries on the development of the mussel stocks with and without fisheries in 39 pairwise studied impact and control plots. Stocks on seed beds in areas of the sublittoral Western Wadden Sea that are known as unstable, show a large decline within one year after settlement, also when there is no seed fishery. Harvesting seed on more stable beds in Spring results in a statistical significant reduction in stock size, which lasts for a period of two years after the first fishery. For the longer term, there is a gradual decline of the mussel stocks on all studied plots. On three out of the 39 plots, mussel biomass showed a large increase, both on control and impact parts. Also these mussel beds declined and eventually disappeared. A difference in life expectancy of fished and unfished beds was not demonstrated. It is concluded that sublittoral beds gradually disappear, also without fisheries. As a consequence, new recruitment is of critical importance for the long-term survival of sublittoral mussel beds. As we found no significant difference between recruitment on fished and control parts, there are no indications for negative impacts of seed fishery on new recruitment.

    Design of a reference architecture for developing smart warehouses in industry 4.0
    Geest, Maarten van; Tekinerdogan, Bedir ; Catal, Cagatay - \ 2021
    Computers in Industry 124 (2021). - ISSN 0166-3615
    Case study research - Reference architecture - Smart warehouses - Software architecture

    Smart warehousing aims at increasing the overall service quality, productivity, and efficiency while minimizing the costs and failures. For designing the reference architecture, we apply a domain-driven architecture design approach and use the architecture design knowledge as presented in the software architecture design literature. We first provide the results of a thorough domain analysis process to smart warehouses to identify the key concerns that shape the architecture of smart warehouses. The domain model is presented using feature diagrams that show the common and variant features of smart warehouses. The domain analysis process is followed by the architecture design process, whereby we have used architecture viewpoints for modeling the reference architecture. Different businesses require different kinds of smart warehouses. Therefore, we present the generic business process model for both traditional warehouses and smart warehouses. The business modeling process is followed by the architecture design process, whereby we have used architecture viewpoints for modeling the reference architecture. Once the reference architecture is designed, a case study has been used to evaluate the proposed reference architecture. The case study has been conducted at a large warehouse in the food industry and illustrates the overall design method and presents the lessons learned.

    The effects of management practices on soil organic carbon stocks of oil palm plantations in Sumatra, Indonesia
    Rahman, Niharika ; Giller, Ken E. ; Neergaard, Andreas de; Magid, Jakob ; Ven, Gerrie van de; Bruun, Thilde Bech - \ 2021
    Journal of Environmental Management 278 (2021). - ISSN 0301-4797
    Best management practices - Residue management - Smallholder - SOC stock - Yield

    The rapid increase in global production of and demand for palm oil has resulted in large-scale expansion of oil palm monoculture in the world's tropical regions, particularly in Indonesia. This expansion has led to the conversion of carbon-rich land-use types to oil palm plantations with a range of negative environmental impacts, including loss of carbon from aboveground biomass and soil. Sequestration of soil organic carbon (SOC) in existing oil palm plantations is an important strategy to limit carbon losses. The aim of this study was to investigate SOC stocks of oil palm plantations under different management systems. Soil samples were collected from three different management systems (best management practices (BMP), current management practices typical of large plantations (CMP) and smallholder management practices (SHMP)) in north Sumatra, Indonesia. Plantations were divided into four management zones that were sampled separately with four replicate profiles in the weeded circle, frond stack, harvesting path and interrow zones. All the soil samples were collected from five (0–5, 5–15, 15–30, 30–50 and 50–70 cm) soil depths. Soil samples were analysed for concentration of SOC, soil texture, soil bulk density and pH. Calculations of SOC stocks in the soils were undertaken according to the fixed-depth and equivalent soil mass approaches. Results showed that SOC stocks of plantations under BMP (68 t ha−1) were 31% and 18% higher than under CMP (57 t ha−1) and SHMP (46 t ha−1) respectively. In the BMP system, soils under the interrow zone that received enriched mulch and frond stack positions stored significantly more SOC than the harvesting path of the BMP system (77, 73 and 57 t ha−1 respectively). BMP also had a 33% higher fresh fruit bunch yield compared to the SHMP system. This study shows that residue incorporation or retention as a part of BMP could be an effective strategy for increasing SOC stocks of oil palm plantations and confirms that these management practices could improve yields from SHMP systems.

    Why pathogens matter for meeting the united nations’ sustainable development goal 6 on safely managed water and sanitation
    Mraz, Alexis L. ; Tumwebaze, Innocent K. ; McLoughlin, Shane R. ; McCarthy, Megan E. ; Verbyla, Matthew E. ; Hofstra, Nynke ; Rose, Joan B. ; Murphy, Heather M. - \ 2021
    Water Research 189 (2021). - ISSN 0043-1354

    Water and wastewater utilities, water and sanitation hygiene (WASH) practitioners, and regulating bodies, particularly in developing nations, rely heavily on indicator microorganisms, as opposed to pathogens, for much of their regulatory decisions. This commentary illustrates the importance of considering pathogens and not relying only on indicator organisms when making decisions regarding water and sanitation, especially with respect to meeting the current targets of the Sustainable Development Goal (SDG) 6. We use quantitative microbial risk assessment (QMRA) to present three common scenarios that WASH and public health practitioners encounter to illustrate our point. These include 1) chlorination of surface water for drinking, 2) land application of latrine waste as a fertilizer, and 3) recreation/domestic use of surface waters impacted by wastewater discharge. We show that the calculated probabilities of risk of infection are statistically significantly higher when using treatment/survival information for pathogens versus using indicator species data. Thus, demonstrating that relying solely on indicators for sanitation decision making is inadequate if we truly want to achieve the SDG6 targets of safely managed water and sanitation services.

    Quantification of bovine α-lactalbumin in infant milk formula using LC-MS
    Kleinnijenhuis, Anne J. ; Gool, Martine P. van; Holthoon, Frédérique L. van; Noort, Maarten van den; Huppertz, Thom - \ 2021
    International Dairy Journal 113 (2021). - ISSN 0958-6946
    α-Lactalbumin (α-la) provides essential amino acids to the diet and is therefore of nutritional importance. Bovine α-la is routinely supplemented to infant formulas, which makes it essential to obtain quantitative data of its content. In this study a quantitative, internally standardised Liquid Chromatography-Mass Spectrometry (LC-MS) method for bovine α-la in infant formula was validated, with good accuracy (90–110%) and precision (RSDRint < 7%). The specificity was high because the bovine α-la calibration samples were prepared with goat milk-based infant formula to avoid background of the endogenous bovine target peptide (CEVFR). Additionally, the method includes the qualitative monitoring of (i) a second confirmative tryptic peptide from the bovine α-la sequence (VGINYWLAHK), (ii) glycation of adjacent lysine residues and (iii) the presence of goat α-la adulteration in bovine infant milk formula. The methodology will be of importance to the dairy and infant formula industry in supporting bovine α-la label claims.
    Sequential adsorption and interfacial displacement in emulsions stabilized with plant-dairy protein blends
    Hinderink, E.B.A. ; Sagis, L.M.C. ; Schroen, C.G.P.H. ; Berton-Carabin, C.C. - \ 2021
    Journal of Colloid and Interface Science 583 (2021). - ISSN 0021-9797 - p. 704 - 713.
    Interfacial displacement - Interfacial rheology - Animal-plant protein mixture - Interfacial structure - Competitive adsorption - Food emulsions - Protein-stabilized emulsions - Oil-water interface
    Hypothesis: Many traditional or emergent emulsion products contain mixtures of proteins, resulting in complex, non-equilibrated interfacial structures. It is expected that protein displacement at oil-water interfaces depends on the sequence in which proteins are introduced during emulsion preparation,
    and on its initial interfacial composition.
    Experiments: We produced emulsions with whey, pea or a whey-pea protein blend and added extra protein post-emulsification. The surface load was measured indirectly via the continuous phase, or directly via the creamed phase. The interfacial composition was monitored over a three-day period using SDSPAGE
    densitometry. We compared these findings with results obtained using an automated drop tensiometer with bulk-phase exchange to highlight the effect of sequential protein adsorption on interfacial tension and dilatational rheology.
    Findings: Addition of a second protein increased the surface load; especially pea proteins adsorbed to pre-adsorbed whey proteins, leading to thick interfacial layers. The addition of whey proteins to a pea
    Protist taxonomic and functional diversity in soil, freshwater and marine ecosystems
    Singer, David ; Seppey, Christophe V.W. ; Lentendu, Guillaume ; Dunthorn, Micah ; Bass, David ; Belbahri, Lassâad ; Blandenier, Quentin ; Debroas, Didier ; Groot, G.A. De; Vargas, Colomban De; Domaizon, Isabelle ; Duckert, Clément ; Izaguirre, Irina ; Koenig, Isabelle ; Mataloni, Gabriela ; Schiaffino, M.R. ; Mitchell, Edward A.D. ; Geisen, Stefan ; Lara, Enrique - \ 2021
    Environment International 146 (2021). - ISSN 0160-4120
    Protists dominate eukaryotic diversity and play key functional roles in all ecosystems, particularly by catalyzing carbon and nutrient cycling. To date, however, a comparative analysis of their taxonomic and functional diversity that compares the major ecosystems on Earth (soil, freshwater and marine systems) is missing. Here, we present a comparison of protist diversity based on standardized high throughput 18S rRNA gene sequencing of soil, freshwater and marine environmental DNA. Soil and freshwater protist communities were more similar to each other than to marine protist communities, with virtually no overlap of Operational Taxonomic Units (OTUs) between terrestrial and marine habitats. Soil protists showed higher γ diversity than aquatic samples. Differences in taxonomic composition of the communities led to changes in a functional diversity among ecosystems, as expressed in relative abundance of consumers, phototrophs and parasites. Phototrophs (eukaryotic algae) dominated freshwater systems (49% of the sequences) and consumers soil and marine ecosystems (59% and 48%, respectively). The individual functional groups were composed of ecosystem- specific taxonomic groups. Parasites were equally common in all ecosystems, yet, terrestrial systems hosted more OTUs assigned to parasites of macro-organisms while aquatic systems contained mostly microbial parasitoids. Together, we show biogeographic patterns of protist diversity across major ecosystems on Earth, preparing the way for more focused studies that will help understanding the multiple roles of protists in the biosphere.
    Fractionation platform for target identification using off-line directed two-dimensional chromatography, mass spectrometry and nuclear magnetic resonance
    Laan, Tom van der; Elfrink, Hyung ; Azadi-Chegeni, Fatemeh ; Dubbelman, Anne Charlotte ; Harms, Amy C. ; Jacobs, Doris M. ; Braumann, Ulrich ; Velders, Aldrik H. ; Duynhoven, John van; Hankemeier, Thomas - \ 2021
    Analytica Chimica Acta 1142 (2021). - ISSN 0003-2670 - p. 28 - 37.
    Food - Identification - Mass spectrometry - Metabolomics - Nuclear magnetic resonance spectroscopy - Two-dimensional chromatography

    The unambiguous identification of unknown compounds is of utmost importance in the field of metabolomics. However, current identification workflows often suffer from error-sensitive methodologies, which may lead to incorrect structure annotations of small molecules. Therefore, we have developed a comprehensive identification workflow including two highly complementary techniques, i.e. liquid chromatography (LC) combined with mass spectrometry (MS) and nuclear magnetic resonance spectroscopy (NMR), and used it to identify five taste-related retention time and m/z features in soy sauce. An off-line directed two-dimensional separation was performed in order to purify the features prior to the identification. Fractions collected during the first dimension separation (reversed phase low pH) were evaluated for the presence of remaining impurities next to the features of interest. Based on the separation between the feature and impurities, the most orthogonal second dimension chromatography (hydrophilic interaction chromatography or reversed phase high pH) was selected for further purification. Unknown compounds down to tens of micromolar concentrations were tentatively annotated by MS and structurally confirmed by MS and NMR. The mass (0.4–4.2 μg) and purity of the isolated compounds were sufficient for the acquisition of one and two-dimensional NMR spectra. The use of a directed two-dimensional chromatography allowed for a fractionation that was tailored to each feature and remaining impurities. This makes the fractionation more widely applicable to different sample matrices than one-dimensional or fixed two-dimensional chromatography. Five proline-based 2,5-diketopiperazines were successfully identified in soy sauce. These cyclic dipeptides might contribute to taste by giving a bitter flavour or indirectly enhancing umami flavour.

    Variability in lag duration of Listeria monocytogenes strains in half Fraser enrichment broth after stress affects the detection efficacy using the ISO 11290-1 method
    Bannenberg, Jasper W. ; Abee, Tjakko ; Zwietering, Marcel H. ; Besten, Heidy M.W. den - \ 2021
    International Journal of Food Microbiology 337 (2021). - ISSN 0168-1605
    Detection - Enrichment - Half Fraser broth - ISO 11290-1:2017 - Listeria monocytogenes

    A collection of 23 Listeria monocytogenes strains of clinical and food origin was tested for their ability to recover and grow out in half Fraser enrichment broth following the ISO 11290-1:2017 protocol. Recovery of sub-lethally heat-injured cells in half Fraser broth was compared to reference cells with no stress pre-treatment. The enrichments were followed over time by plate counts and the growth parameters were estimated with the 3-phase model which described the data best. The reference cells without stress pre-treatment showed a short lag duration, which ranged from 1.4 to 2.7 h. However, significant variation in the ability to recover after 60 °C heat stress was observed among the tested strains and resulted in a lag duration from 4.7 to 15.8 h. A subset of strains was also exposed to low-temperature acid stress, and the lag duration showed to be also stress dependent. Scenario analyses and Monte Carlo simulations were carried out using the growth parameters obtained in the enrichments. This demonstrated that when starting with one cell, the detection threshold for efficient transfer of at least one cell to the secondary enrichment step, i.e. 2 log10 CFU/ml, was not reached by 11 of 23 strains tested (48%) after exposure to 60 °C heat stress. Increasing the incubation time from 24 to 26 h and the transfer volume from 0.1 to 1.0 ml can increase the average probability to transfer at least one cell to the secondary enrichment step from 79.9% to 99.0%. When optimizing enrichment procedures, it is crucial to take strain variability into account as this can have a significant impact on the detection efficacy.

    Predicting soil properties in 3D: Should depth be a covariate?
    Ma, Yuxin ; Minasny, Budiman ; McBratney, Alex ; Poggio, Laura ; Fajardo, Mario - \ 2021
    Geoderma 383 (2021). - ISSN 0016-7061
    3D mapping - Average prediction interval - Digital soil mapping - Tree-based model
    Soil is a three-dimensional volume with property variability in all three dimensions. In Digital Soil Mapping (DSM), the variation of soil properties down a profile is usually harmonised by the use of the equal-area spline depth function approach. Soil observations at various depth intervals are harmonised to pre-determined depth intervals. To create maps of soil at the defined depth intervals, 2.5D model produces maps of individual depth intervals separately. Those maps can be reconstructed to produce a continuous depth function for each predicted location. More recently, several studies propose that soil property at any depth can be mapped using a model incorporating depth along with spatial covariates as predictor variables, creating a ‘3D’ model. The aim of this study is to evaluate the proposition that soil properties can be predicted at any depth. This study compares the 2.5D model and 3D model in two areas. The first test is on a 1500 km2 area in Edgeroi, New South Wales (NSW), Australia, mapping soil organic carbon (SOC, %), carbon storage (kg m−2), pH (H2O), clay content (%), and cation exchange capacity (CEC, mg/kg) based on depth-interval observations. The second study area in the Lower Hunter Valley has SOC observations at every 2 cm increment from a 210 km2 area. 2.5D and 3D models were tested in both study areas using four machine learning techniques: Cubist regression tree, Quantile Regression Forest (QRF), Artificial Neural Network (ANN), and 3D Generalised Additive Model (GAM). Results show that, in terms of R2 and RMSE, 2.5D and 3D models using different machine learning models produce comparable results on the validation of depth interval observations. The 3D tree-based models produce “stepped” prediction of properties with depth. Results on the Hunter Valley area with point observations show that the 3D model cannot replicate field point observations. 3D soil mapping on point depth observation has lower accuracy and larger uncertainty compared to the 2.5D model. For future DSM studies, 3D soil mapping with depth as a covariate requires caution with respect to the prediction method and the requirements of the results.
    Reducing greenhouse gas emissions of New Zealand beef through better integration of dairy and beef production
    Selm, Benjamin van; Boer, Imke J.M. de; Ledgard, Stewart F. ; Middelaar, Corina E. van - \ 2021
    Agricultural Systems 186 (2021). - ISSN 0308-521X
    Cattle - Dairy beef - Greenhouse gas - Life cycle assessment
    Integrating dairy and beef production offers opportunities to reduce greenhouse gas (GHG) emissions of beef production, which is dominated by emissions related to maintenance of the breeding cow. This study aims to quantify the GHG reduction potential of the New Zealand (NZ) beef sector when replacing beef breeding cows and their calves with dairy beef animals. To this end, we combined a cattle herd model of NZ beef and dairy production with GHG emission calculations of beef production. We computed GHG emissions (to farm-gate stage) of the current amount of beef produced, while increasing the number of dairy beef calves at the expense of the number of suckler-beef calves. GHG emissions were 29% lower per kg carcass weight for dairy beef animals compared to suckler-beef animals. The average emission intensity decreased from 21.3 to 16.7 kg CO2e per kg carcass weight (−22%) as the number of suckler-beef animals declined to zero and dairy beef animals increased. Integrating dairy and beef production would enable the NZ beef sector to reduce annual GHG emissions by nearly 2000 kt CO2e (i.e. 22% of the total sector's emissions), while the dairy sector would improve their social licence to operate by reducing the number of surplus dairy calves slaughtered from 4-days old.
    Critical success and risk factors for circular business models valorising agricultural waste and by-products
    Donner, Mechthild ; Verniquet, Anne ; Broeze, Jan ; Kayser, Katrin ; Vries, Hugo De - \ 2021
    Resources, Conservation and Recycling 165 (2021). - ISSN 0921-3449
    Agricultural waste valorisation - Bioeconomy - Business models - Circular economy - Success factors
    For a transition from a linear, ‘take-make-dispose’ economy to a sustainable usage of all constituents of renewable resources in cascading and circular pathways, new business models valorising streams that are currently considered as waste are needed. The aim of this article is to understand critical success and risk factors of eco-innovative business models that contribute to a circular economy via agricultural unavoidable waste or by-products valorisation. 39 cases were studied focusing on agricultural side stream conversion into valuable products. Semi-structured interviews were performed and secondary data collected. Cases were analysed according to types of initiatives, main objectives, resources and valorisation pathways, as well as external and internal factors that have influenced the businesses over time. Following success and risk factor categories are identified: (1) technical and logistic, (2) economic, financial and marketing, (3) organisational and spatial, (4) institutional and legal, (5) environmental, social and cultural. Herein, specific factors for the agricultural sector are innovative conversion technologies, flexible in and out logistics, joint investments in R&D, price competitiveness for bio-based products, partnerships with research organisations, space availability, subsidies, agricultural waste management regulations, local stakeholder involvement and acceptance of bio-based production processes. Insights from this study can help farmers and agribusiness managers by defining and adapting their strategies within their local contexts. They also show that for shifting from linear agro-food chains to a circular system, individual businesses need to evolve towards more dynamic and integrated business models, in which the macro-environment sets the boundary conditions for successful operations.
    Influence of lactose pre-crystallization on the storage stability of infant formula powder containing lactose and maltodextrin
    Saxena, Juhi ; Adhikari, Benu ; Brkljaca, Robert ; Huppertz, Thom ; Zisu, Bogdan ; Chandrapala, Jayani - \ 2021
    Food Hydrocolloids 111 (2021). - ISSN 0268-005X
    Hydrolyzed whey protein - Infant formula - Lactose pre-crystallization - Maltodextrin - Surface free fat - XRD
    The effect of different proportions of pre-crystallized lactose (PCL; 0–31%) on the physico-chemical properties of fresh and aged infant formula (IF) containing lactose and maltodextrin was investigated. Fresh powders with a higher proportion of PCL had a larger particle size and higher surface free fat and water activity (aw). Powders with 7–24% PCL showed a lower rate of increase in aw and lactose crystallinity during storage at RH 54% compared to the control. Aw correlated linearly with the glass transition temperature (Tg) and the relative effect of storage temperature on Tg was lower in samples with 7–24% PCL at RH 33%. Significantly (p < 0.05) lower surface free fat, particle size and color changes were observed in samples with 18–24% PCL under all ageing conditions (RH 11–54% and 25–45 °C). The presence of maltodextrin was found to work in conjunction with PCL to improve physicochemical properties and storage stability of IF powders.
    Energy savings in greenhouses by transition from high-pressure sodium to LED lighting
    Katzin, David ; Marcelis, Leo F.M. ; Mourik, Simon van - \ 2021
    Applied Energy 281 (2021). - ISSN 0306-2619
    Greenhouses in high latitudes consume vast amounts of energy for heating and supplemental lighting. Light emitting diodes (LEDs) have been suggested as having great potential for reducing greenhouse energy use, as they are extremely efficient at converting electricity to light. However, LEDs emit very little heat, which must be compensated by the greenhouse heating system. Thus, it is unclear how much energy can be saved by LEDs when the need for extra heating is taken into account. This study presents a first analysis of the energy demands for greenhouses transitioning from high-pressure sodium (HPS) to LED lighting, providing a quantification of the total energy savings achieved by LEDs. Model simulations using GreenLight, an open source greenhouse model, were used to examine a wide range of climates, from subtropical China to arctic Sweden, and multiple settings for indoor temperature, lamp intensity, lighting duration, and insulation. In most cases, the total energy saving by transition to LEDs was 10–25%. This value was linearly correlated with the fraction of energy used for lighting before the transition, which was 40–80%. In all scenarios, LEDs reduced the energy demand for lighting but increased the demand for heating. Since energy for lighting and heating is often derived from different origins, the benefits of a transition to LEDs depend on the environmental and financial costs of the available energy sources. The framework provided here can be used to select lighting installations that make optimal use of available energy resources in the most efficient and sustainable manner.
    Phenology-based sample generation for supervised crop type classification
    Belgiu, Mariana ; Bijker, Wietske ; Csillik, Ovidiu ; Stein, Alfred - \ 2021
    International Journal of applied Earth Observation and Geoinformation 95 (2021). - ISSN 0303-2434
    Abstract

    Crop type mapping is relevant to a wide range of food security applications. Supervised classification methods commonly generate these data from satellite image time-series. Yet, their successful implementation is hindered by the lack of training samples. Solutions like transfer learning, development of temporal-spectral signatures of the target classes, re-utilization of existing inventories, or crowdsourcing initiatives are commonly applied to generate samples for thematically coarser classifications. These methods are rarely used for generating crop types samples. In this study, we leverage the phenology information of existing data inventories using Time-Weighted Dynamic Time Warping (TWDTW) to address the problem of automatic crop sample generation in two target areas. Resulting labeled samples are refined using proximity measures obtained from Random Forests (RF). Sentinel-2 time-series are used to obtain phenology information from two study areas. The proposed methodology achieved promising results for classes with a reduced inter-classes similarity such as sugar beets (user’s accuracy, UA, of 98% and producer’s accuracy, PA, of 100%) or grains (UA of 98% and PA of 90%). The crops with a high inter-classes similarity yielded less satisfactory results. Potatoes, for example, obtained a high PA of 95%, but a UA of only 36% because of the spectral-temporal similarity with maize. The methodology works well for areas with balanced crop samples. Yet, it favors prevalent classes in areas with imbalanced crops at the expense of a low accuracy for the minority crops. Despite these shortcomings, the proposed methodology offers a viable option to generate crop samples in regions with few ground labels.
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