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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Agricultural nitrogen and phosphorus emissions to water and their mitigation options in the Haihe Basin, China
Zhao, Zhanqing ; Qin, Wei ; Bai, Zhaohai ; Ma, Lin - \ 2019
Agricultural Water Management 212 (2019). - ISSN 0378-3774 - p. 262 - 272.
Crop-livestock system - Haihe Basin - Nitrogen - NUFER - Phosphorus - Water pollution

Agricultural nitrogen (N) and phosphorus (P) emissions to water bodies remain largely unknown in China, mainly due to the lack of reliable data sources and quantification tools. In this study, we constructed a grid-based NUFER (NUtrient Flow in food chains, Environment and Resources use) model in order to quantify a high-resolution agricultural N and P emissions to water bodies in Haihe Basin in 2012, based on data collected from county-level statistics, farm interview, and spatial data of topography, climate, soil texture, and land use. We also explored the mitigation strategies in 2030 via scenario analysis. The results showed that total agricultural N emission to water bodies in Haihe Basin was 1079 Gg N in 2012, of which cropland contributed 54%; total agricultural P emission to water bodies was 208 Gg P, livestock contributed 78%. There were large spatial variations in agricultural N and P emissions. Overall, the plain areas accounted for around 80% of the total agricultural N and P emissions to water in 2012. The highest N and P emission intensities were 10 t N km−2 and 2 t P km−2, respectively. N and P emissions were significantly related to anthropogenic factors (such as the livestock density and cropland) in the plain areas; whereas in mountainous areas, both anthropogenic and natural factors (e.g., slope deviation and soil texture) significantly affected N and P emissions. Our scenario analysis suggests that agricultural N and P emissions can be reduced by up to 45% and 77%, respectively for N and P in 2030, via improved agricultural and environmental policies, technologies and managements. The prohibition of direct animal manure discharge to the water system seems to be the most effective measure to mitigate the emissions. Our study provided a high-resolution agricultural N and P emissions to the water bodies of Haihe Basin and identified the most effective options to reduce these emissions in highly intensified agricultural areas.

Modeling nutrients in Lake Dianchi (China) and its watershed
Li, Xiaolin ; Janssen, Annette B.G. ; Klein, Jeroen J.M. de; Kroeze, Carolien ; Strokal, Maryna ; Ma, Lin ; Zheng, Yi - \ 2019
Agricultural Water Management 212 (2019). - ISSN 0378-3774 - p. 48 - 59.
Critical loading - MARINA nutrient model - Mining - PCLake ecosystem model - River export of nutrients

Lake Dianchi suffered from severe eutrophication for decades. Past efforts to reduce the eutrophication were not very effective. The objective of this study is to improve our understanding of nitrogen (N) and phosphorus (P) loadings and to analyze to what extent they exceed critical nutrient loadings of Lake Dianchi. To this end, we applied the nutrient MARINA model and the ecosystem model PCLake. Results show that river export of dissolved N and P was high in 2012. About 6 209 ton of total dissolved N (TDN) was exported to the lake (i.e. 23.6 kg ha−1), of which more than two-thirds in the form of dissolved inorganic N. For total dissolved P, this export was about 413 ton (i.e. 1.6 kg ha−1), of which 75% dissolved inorganic P. Urban sewage is a major source of nutrients in rivers in the northern sub-basins. In southern sub-basins, agriculture is an important source of both N and P, while P mining and processing is a major source of dissolved inorganic P. Nutrient inputs to the lake are particularly high from urbanization sub-basins draining into the northern part of the lake (Caohai). Critical nutrient loadings for the northern part of the lake (Caohai) are 0.34 mg P m−2d−1 (3.06 mg N m−2d−1) and for the southern part (Waihai) 0.38 mg P m−2d−1 (3.42 mg N m−2d−1). Actual loadings exceed the critical nutrient loadings by 82 times and 17 times of Caohai and Waihai, respectively. Our study illustrates how linking MARINA with PCLake helped to quantify the causes of lake eutrophication and to identify critical loadings for N and P in the lake. Our study can assist local authorities to formulate management options to reduce nutrient pollution in Lake Dianchi in the future.

Implications of crop model ensemble size and composition for estimates of adaptation effects and agreement of recommendations
Rodríguez, A. ; Ruiz-Ramos, M. ; Palosuo, T. ; Carter, T.R. ; Fronzek, S. ; Lorite, I.J. ; Ferrise, R. ; Pirttioja, N. ; Bindi, M. ; Baranowski, P. ; Buis, S. ; Cammarano, D. ; Chen, Y. ; Dumont, B. ; Ewert, F. ; Gaiser, T. ; Hlavinka, P. ; Hoffmann, H. ; Höhn, J.G. ; Jurecka, F. ; Kersebaum, K.C. ; Krzyszczak, J. ; Lana, M. ; Mechiche-Alami, A. ; Minet, J. ; Montesino, M. ; Nendel, C. ; Porter, J.R. ; Ruget, F. ; Semenov, M.A. ; Steinmetz, Z. ; Stratonovitch, P. ; Supit, I. ; Tao, F. ; Trnka, M. ; Wit, A. de; Rötter, R.P. - \ 2018
Agricultural and Forest Meteorology (2018). - ISSN 0168-1923 - 12 p.
Climate change - Decision support - Outcome confidence - Response surface - Uncertainty - Wheat adaptation

Climate change is expected to severely affect cropping systems and food production in many parts of the world unless local adaptation can ameliorate these impacts. Ensembles of crop simulation models can be useful tools for assessing if proposed adaptation options are capable of achieving target yields, whilst also quantifying the share of uncertainty in the simulated crop impact resulting from the crop models themselves. Although some studies have analysed the influence of ensemble size on model outcomes, the effect of ensemble composition has not yet been properly appraised. Moreover, results and derived recommendations typically rely on averaged ensemble simulation results without accounting sufficiently for the spread of model outcomes. Therefore, we developed an Ensemble Outcome Agreement (EOA) index, which analyses the effect of changes in composition and size of a multi-model ensemble (MME) to evaluate the level of agreement between MME outcomes with respect to a given hypothesis (e.g. that adaptation measures result in positive crop responses). We analysed the recommendations of a previous study performed with an ensemble of 17 crop models and testing 54 adaptation options for rainfed winter wheat (Triticum aestivum L.) at Lleida (NE Spain) under perturbed conditions of temperature, precipitation and atmospheric CO2 concentration. Our results confirmed that most adaptations recommended in the previous study have a positive effect. However, we also showed that some options did not remain recommendable in specific conditions if different ensembles were considered. Using EOA, we were able to identify the adaptation options for which there is high confidence in their effectiveness at enhancing yields, even under severe climate perturbations. These include substituting spring wheat for winter wheat combined with earlier sowing dates and standard or longer duration cultivars, or introducing supplementary irrigation, the latter increasing EOA values in all cases. There is low confidence in recovering yields to baseline levels, although this target could be attained for some adaptation options under moderate climate perturbations. Recommendations derived from such robust results may provide crucial information for stakeholders seeking to implement adaptation measures.

Biological treatment of produced water coupled with recovery of neutral lipids
Sudmalis, D. ; Silva, P. da; Temmink, H. ; Bijmans, M.M. ; Pereira, M.A. - \ 2018
Water Research 147 (2018). - ISSN 0043-1354 - p. 33 - 42.
Alkane biodegradation - Biological treatment - Neutral lipids production - Produced water

Produced water (PW) is the largest waste stream generated by oil and gas industry. It is commonly treated by physical-chemical processes due to high salt content and poor biodegradability of water insoluble compounds, such as n-alkanes. N-alkanes can represent a major fraction of organic contaminants within PW. In this study the possibility of simultaneous n – alkane biodegradation and production of neutral lipids in a concentrated PW stream with A. borkumenis SK2 as the sole reactor inoculum was investigated. N-alkane removal efficiency up to 99.6%, with influent alkane COD of 7.4 g/L, was achieved in a continuously operated reactor system. Gas chromatography results also showed that the majority of other non-polar compounds present in the PW were biodegraded. Biodegradation of n-alkanes was accompanied by simultaneous production of neutral lipids, mostly wax ester (WE)-alike compounds. We demonstrate, that under nutrient limited conditions and 108.9 ± 3.3 mg/L residual n-alkane concentration the accumulation of extracellular WE-alike compounds can be up to 12 times higher compared to intracellular, reaching 3.08 grams per litre of reactor volume (g/Lreactor) extracellularly and 0.28 g/Lreactor intracellularly. With residual n-alkane concentration of 311.5 ± 34.2 mg/L accumulation of extracellular and intracellular WE-alike compounds can reach up to 6.15 and 0.91 g/Lreactor, respectively. To the best of our knowledge simultaneous PW treatment coupled with production of neutral lipids has never been demonstrated before.

Modulation of plant-mediated interactions between herbivores of different feeding guilds : Effects of parasitism and belowground interactions
Vaello, Teresa ; Sarde, Sandeep J. ; Marcos-García, Mª Ángeles ; Boer, Jetske G. de; Pineda, Ana - \ 2018
Scientific Reports 8 (2018)1. - ISSN 2045-2322

Herbivory affects subsequent herbivores, mainly regulated by the phytohormones jasmonic (JA) and salicylic acid (SA). Additionally, organisms such as soil microbes belowground or parasitoids that develop inside their herbivorous hosts aboveground, can change plant responses to herbivory. However, it is not yet well known how organisms of trophic levels other than herbivores, below- and above-ground, alter the interactions between insect species sharing a host plant. Here, we investigated whether the parasitoid Aphidius colemani and different soil microbial communities (created through plant-soil feedbacks) affect the JA and SA signalling pathways in response to the aphid Myzus persicae and the thrips Frankliniella occidentalis, as well as subsequent thrips performance. Our results show that the expression of the JA-responsive gene CaPINII in sweet pepper was more suppressed by aphids than by parasitised aphids. However, parasitism did not affect the expression of CaPAL1, a biosynthetic gene of SA. Furthermore, aphid feeding enhanced thrips performance compared with uninfested plants, but this was not observed when aphids were parasitised. Soils where different plant species were previously grown, did not affect plant responses or the interaction between herbivores. Our study shows that members of the third trophic level can modify herbivore interactions by altering plant physiology.

Investigating the thermal stability of TT-OSL main source trap
Faershtein, Galina ; Guralnik, Benny ; Lambert, Renske ; Matmon, Ari ; Porat, Naomi - \ 2018
Radiation Measurements 119 (2018). - ISSN 1350-4487 - p. 102 - 111.
Kinetic parameters - Thermal stability - TT-OSL

Thermally-Transferred Optically Stimulated Luminescence (TT-OSL) from quartz is an extended-range luminescence dating technique, with an assumed potential to date sediments as old as early Pleistocene (0.8–2.6 Ma). However, one of the main drawbacks of the TT-OSL signal is its relatively low thermal stability. The few and scattered estimates in the literature of the relatively low thermal stability highlight the possibility that some reported TT-OSL ages are thermal artefacts (i.e. minimum ages only). In this study, we rigorously investigate the thermal stability of the main TT-OSL source trap, using a combination of laboratory and analytical techniques (varying heating rates, isothermal decay, alongside several models) on multiple aliquots of a modern sand sample from the eastern Mediterranean coastal plain. The varying heating rates method constrains the Arrhenius parameters of the TT-OSL main trap to E = 1.50 ± 0.06 eV and s = 1012.8±0.6 s−1; these values translate into a trap lifetime of 3.2−1.9 +4.8 Ma at 10 °C. Isothermal decay data further exhibits significant departures from first-order kinetic behavior, which can be well captured by either the general order kinetics model, or a Gaussian distribution of first-order systems. However, extrapolations of these models to geological timescales are at odds with a large volume of observations, thus suggesting that the deviation from first-order kinetics may be a laboratory artefact. Overall, our study reinforces the concern, that thermal loss progressively affects the TT-OSL signal in the Ma-scale age range, and that some previously reported results may be “minimum ages” only.

Global DNA Compaction in Stationary-Phase Bacteria Does Not Affect Transcription
Janissen, Richard ; Arens, Mathia M.A. ; Vtyurina, Natalia N. ; Rivai, Zaïda ; Sunday, Nicholas D. ; Eslami-Mossallam, Behrouz ; Gritsenko, Alexey A. ; Laan, Liedewij ; Ridder, Dick de; Artsimovitch, Irina ; Dekker, Nynke H. ; Abbondanzieri, Elio A. ; Meyer, Anne S. - \ 2018
Cell 174 (2018)5. - ISSN 0092-8674 - p. 1188 - 1199.e14.
DNA condensation - Dps - magnetic tweezers - nucleoid - RNA polymerase - single-molecule biophysics - stationary phase - stress response - transcription

In stationary-phase Escherichia coli, Dps (DNA-binding protein from starved cells) is the most abundant protein component of the nucleoid. Dps compacts DNA into a dense complex and protects it from damage. Dps has also been proposed to act as a global regulator of transcription. Here, we directly examine the impact of Dps-induced compaction of DNA on the activity of RNA polymerase (RNAP). Strikingly, deleting the dps gene decompacted the nucleoid but did not significantly alter the transcriptome and only mildly altered the proteome during stationary phase. Complementary in vitro assays demonstrated that Dps blocks restriction endonucleases but not RNAP from binding DNA. Single-molecule assays demonstrated that Dps dynamically condenses DNA around elongating RNAP without impeding its progress. We conclude that Dps forms a dynamic structure that excludes some DNA-binding proteins yet allows RNAP free access to the buried genes, a behavior characteristic of phase-separated organelles. Despite markedly condensing the bacterial chromosome, the nucleoid-structuring protein Dps selectively allows access by RNA polymerase and transcription factors at normal rates while excluding other factors such as restriction endonucleases.

First records of Hyalomma rufipes and Ixodes neitzi (Acari : Ixodidae) found on large carnivores in South Africa
Baauw, Anna H. ; Heyne, Heloise ; Williams, Kathryn S. ; Hill, Russell A. ; Heitkönig, Ignas M.A. ; Williams, Samual T. - \ 2018
Ticks and Tick-borne Diseases (2018). - ISSN 1877-959X - 4 p.
Brown hyena - Hyalomma rufipes - Ixodes neitzi - Leopard

Ixodid ticks (Acari: Ixodidae) are important disease vectors for large carnivores, but the composition of the tick communities that parasitize carnivores is poorly understood. We collected ticks from leopards (Panthera pardus) and brown hyenas (Hyaena brunnea) in the Soutpansberg Mountains, South Africa, to determine which species feed on these carnivores. We identified a total of eight tick species belonging to six genera, and recorded Ixodes neitzi and Hyalomma rufipes on P. pardus for the first time.

Changes in work practices for safe use of formaldehyde in a university-based anatomy teaching and research facility
Scheepers, Paul T.J. ; Graumans, Martien H.F. ; Beckmann, Gwendolyn ; Dael, Maurice van; Anzion, Rob B.M. ; Melissen, Maarten ; Pinckaers, Nicole ; Wel, Luuk van; Werdt, Laurie M.A. de; Gelsing, Vera ; Linge, Albert van - \ 2018
International Journal of Environmental Research and Public Health 15 (2018)9. - ISSN 1661-7827
Carcinogenicity - Exposure assessment - Occupational hygiene - Risk assessment - Risk management

Anatomy teaching and research relies on the use of formaldehyde (FA) as a preservation agent for human and animal tissues. Due to the recent classification of FA as a carcinogen, university hospitals are facing a challenge to (further) reduce exposure to FA. The aim of this study was to reduce exposure to FA in the anatomy teaching and research facility. Workers participated in the development of improved work practices, both technical and organizational solutions. Over a period of 6 years mitigating measures were introduced, including improvement of a down-flow ventilation system, introduction of local exhaust ventilation, collection of drain liquid from displayed specimens in closed containers and leak prevention. Furthermore, some organizational changes were made to reduce the number of FA peak exposures. Stationary and personal air sampling was performed in three different campaigns to assess the effect of these new work practices on inhalation exposure to FA. Samples were collected over 8 h (full shift) and 15 min (task-based) to support mitigation of exposure and improvement of work practices. Air was collected on an adsorbent coated with 2,4-dinitrophenylhydrazine (DNPH) and analyzed by HPLC-UV. Geometric mean (GM) concentrations of FA in the breathing zone over a work-shift were 123 µg/m3 in 2012 and 114 µg/m3 in 2014, exceeding the workplace standard of 150 µg/m3 (8 h time-weighted average, TWA) on 46% of the workdays in 2012 and 38% of the workdays in 2014. This exposure was reduced to an average of 28.8 µg/m3 in 2017 with an estimated probability of exceeding the OEL of 0.6%. Task-based measurements resulted in a mean peak exposures of 291 µg/m3 in 2012 (n = 19) and a mean of 272 µg/m3 in 2014 (n = 21), occasionally exceeding the standard of 500 µg/m3 (15 min TWA), and were reduced to a mean of 88.7 µg/m3 in 2017 (n = 12) with an estimated probability of exceeding the OEL of 1.6%.

Effects of exercise on brain plasticity, cognition and foraging behaviour in Atlantic salmon
Mes, Daan ; Palstra, A.P. ; Henkel, C.V. ; Vindas, M.A. ; Mayer, I. - \ 2018
Brechas de rendimeinto en el cultivo de palma de aceite: una revision cuantitativa de factores determinantes
Woittiez, L.S. ; Wijk, Mark T. van; Slingerland, M.A. ; Noordwijk, M. van; Giller, K.E. - \ 2018
- p. 16 - 68.
Environmental and taxonomic controls of carbon and oxygen stable isotope composition in Sphagnum across broad climatic and geographic ranges
Granath, Gustaf ; Rydin, Håkan ; Baltzer, Jennifer L. ; Bengtsson, Fia ; Boncek, Nicholas ; Bragazza, Luca ; Bu, Zhao Jun ; Caporn, Simon J.M. ; Dorrepaal, Ellen ; Galanina, Olga ; GaÅka, Mariusz ; Ganeva, Anna ; Gillikin, David P. ; Goia, Irina ; Goncharova, Nadezhda ; Hájek, Michal ; Haraguchi, Akira ; Harris, Lorna I. ; Humphreys, Elyn ; Jiroušek, Martin ; KajukaÅo, Katarzyna ; Karofeld, Edgar ; Koronatova, Natalia G. ; Kosykh, Natalia P. ; Lamentowicz, Mariusz ; Lapshina, Elena ; Limpens, Juul ; Linkosalmi, Maiju ; Ma, Jin Ze ; Mauritz, Marguerite ; Munir, Tariq M. ; Natali, Susan M. ; Natcheva, Rayna ; Noskova, Maria ; Payne, Richard J. ; Pilkington, Kyle ; Robinson, Sean ; Robroek, Bjorn J.M. ; Rochefort, Line ; Singer, David ; Stenøien, Hans K. ; Tuittila, Eeva Stiina ; Vellak, Kai ; Verheyden, Anouk ; Michael Waddington, James ; Rice, Steven K. - \ 2018
Biogeosciences 15 (2018)16. - ISSN 1726-4170 - p. 5189 - 5202.

Rain-fed peatlands are dominated by peat mosses (Sphagnum sp.), which for their growth depend on nutrients, water and CO2 uptake from the atmosphere. As the isotopic composition of carbon (12,13C) and oxygen (16,18O) of these Sphagnum mosses are affected by environmental conditions, Sphagnum tissue accumulated in peat constitutes a potential long-term archive that can be used for climate reconstruction. However, there is inadequate understanding of how isotope values are influenced by environmental conditions, which restricts their current use as environmental and palaeoenvironmental indicators. Here we tested (i) to what extent C and O isotopic variation in living tissue of Sphagnum is species-specific and associated with local hydrological gradients, climatic gradients (evapotranspiration, temperature, precipitation) and elevation; (ii) whether the C isotopic signature can be a proxy for net primary productivity (NPP) of Sphagnum; and (iii) to what extent Sphagnum tissue δ18O tracks the δ18O isotope signature of precipitation. In total, we analysed 337 samples from 93 sites across North America and Eurasia using two important peat-forming Sphagnum species (S. magellanicum, S. fuscum) common to the Holarctic realm. There were differences in δ13C values between species. For S. magellanicum δ13C decreased with increasing height above the water table (HWT, R2 =17%) and was positively correlated to productivity (R2 = 7%). Together these two variables explained 46% of the between-site variation in δ13C values. For S. fuscum, productivity was the only significant predictor of δ13C but had low explanatory power (total R2 = 6%). For δ18O values, approximately 90% of the variation was found between sites. Globally modelled annual δ18O values in precipitation explained 69% of the between-site variation in tissue δ18O. S. magellanicum showed lower δ18O enrichment than S. fuscum (-0.83 ‰ lower). Elevation and climatic variables were weak predictors of tissue δ18O values after controlling for δ18O values of the precipitation. To summarize, our study provides evidence for (a) good predictability of tissue δ18O values from modelled annual δ18O values in precipitation, and (b) the possibility of relating tissue δ13C values to HWT and NPP, but this appears to be species-dependent. These results suggest that isotope composition can be used on a large scale for climatic reconstructions but that such models should be species-specific.

Designing Vulnerable Zones of Nitrogen and Phosphorus Transfers to Control Water Pollution in China
Bai, Zhaohai ; Lu, Jie ; Zhao, Hao ; Velthof, Gerard L. ; Oenema, Oene ; Chadwick, Dave ; Williams, John R. ; Jin, Shuqin ; Liu, Hongbin ; Wang, Mengru ; Strokal, Maryna ; Kroeze, Carolien ; Hu, Chunsheng ; Ma, Lin - \ 2018
Environmental Science and Technology 52 (2018)16. - ISSN 0013-936X - p. 8987 - 8988.
Rethinking the Use of Seabed Sediment Temperature Profiles to Trace Submarine Groundwater Flow
Kurylyk, B.L. ; Irvine, D.J. ; Mohammed, A.A. ; Bense, V.F. ; Briggs, M.A. ; Loder, J.W. ; Geshelin, Y. - \ 2018
Water Resources Research 54 (2018)7. - ISSN 0043-1397 - p. 4595 - 4614.
continental slope - heat as a groundwater tracer - ocean hydrogeology - offshore groundwater - submarine groundwater discharge - submarine hydrogeology

Submarine groundwater fluxes across the seafloor facilitate important hydrological and biogeochemical exchanges between oceans and seabed sediment, yet few studies have investigated spatially distributed groundwater fluxes in deep-ocean environments such as continental slopes. Heat has been previously applied as a submarine groundwater tracer using an analytical solution to a heat flow equation assuming steady state conditions and homogeneous thermal conductivity. These assumptions are often violated in shallow seabeds due to ocean bottom temperature changes or sediment property variations. Here heat tracing analysis techniques recently developed for terrestrial settings are applied in concert to examine the influences of groundwater flow, ocean temperature changes, and seabed thermal conductivity variations on deep-ocean sediment temperature profiles. Temperature observations from the sediment and bottom ocean water on the Scotian Slope off eastern Canada are used to demonstrate how simple thermal methods for tracing groundwater can be employed if more comprehensive techniques indicate that the simplifying assumptions are valid. The spatial distribution of the inferred groundwater fluxes on the slope suggests a downward groundwater flow system with recharge occurring over the upper-middle slope and discharge on the lower slope. We speculate that the downward groundwater flow inferred on the Scotian Slope is due to density-driven processes arising from underlying salt domes, in contrast with upward slope systems driven by geothermal convection. Improvements in the design of future submarine hydrogeological studies are proposed for thermal data collection and groundwater flow analysis, including new equations that quantify the minimum detectable flux magnitude for a given sensor accuracy and profile length.

Beached bachelors: An extensive study on the largest recorded sperm whale Physeter macrocephalus mortality event in the North Sea
IJsseldijk, Lonneke L. ; Neer, Abbo van; Deaville, Rob ; Begeman, Lineke ; Bildt, Marco van de; Brand, Judith M.A. van den; Brownlow, Andrew ; Czeck, Richard ; Dabin, Willy ; Doeschate, Mariel ten; Herder, Vanessa ; Herr, Helena ; IJzer, Jooske ; Jauniaux, Thierry ; Jensen, Lasse Fast ; Jepson, Paul D. ; Jo, Wendy Karen ; Lakemeyer, Jan ; Lehnert, Kristina ; Leopold, Mardik F. ; Osterhaus, Albert ; Perkins, Matthew W. ; Piatkowski, Uwe ; Prenger-Berninghoff, Ellen ; Pund, Ralf ; Wohlsein, Peter ; Gröne, Andrea ; Siebert, Ursula - \ 2018
PLoS One 13 (2018)8. - ISSN 1932-6203

Between the 8th January and the 25th February 2016, the largest sperm whale Physeter macrocephalus mortality event ever recorded in the North Sea occurred with 30 sperm whales stranding in five countries within six weeks. All sperm whales were immature males. Groups were stratified by size, with the smaller animals stranding in the Netherlands, and the largest in England. The majority (n = 27) of the stranded animals were necropsied and/ or sampled, allowing for an international and comprehensive investigation into this mortality event. The animals were in fair to good nutritional condition and, aside from the pathologies caused by stranding, did not exhibit significant evidence of disease or trauma. Infectious agents were found, including various parasite species, several bacterial and fungal pathogens and a novel alphaherpesvirus. In nine of the sperm whales a variety of marine litter was found. However, none of these findings were considered to have been the primary cause of the stranding event. Potential anthropogenic and environmental factors that may have caused the sperm whales to enter the North Sea were assessed. Once sperm whales enter the North Sea and head south, the water becomes progressively shallower (<40 m), making this region a global hotspot for sperm whale strandings. We conclude that the reasons for sperm whales to enter the southern North Sea are the result of complex interactions of extrinsic environmental factors. As such, these large mortality events seldom have a single ultimate cause and it is only through multidisciplinary, collaborative approaches that potentially multifactorial large-scale stranding events can be effectively investigated.

A linear sequence to facilitate curation of herbarium specimens of Annonaceae
Chatrou, Lars W. ; Turner, Ian M. ; Klitgaard, Bente B. ; Maas, Paul J.M. ; Utteridge, Timothy M.A. - \ 2018
Kew Bulletin 73 (2018)3. - ISSN 0075-5974
This paper provides a linear sequence of four subfamilies, 15 tribes and 106 genera of the magnoliid
family Annonaceae, based on state-of-the-art and stable phylogenetic relationships. The linear sequence facilitates
the organisation of Annonaceae herbarium specimens.
Using a system innovation's approach for stimulating agroforestry adoption
Cuperus, Fogelina ; Schoutsen, M.A. ; Sukkel, W. ; Selin Norén, Isabella ; Wijnands, F.G. - \ 2018
In: Agroforestry as sustainable land use. - - p. 35 - 39.
China’s livestock transition : Driving forces, impacts, and consequences
Bai, Zhaohai ; Ma, Wenqi ; Ma, Lin ; Velthof, Gerard L. ; Wei, Zhibiao ; Havlík, Petr ; Oenema, Oene ; Lee, Michael R.F. ; Zhang, Fusuo - \ 2018
Science Advances 4 (2018)7. - ISSN 2375-2548

China’s livestock industry has experienced a vast transition during the last three decades, with profound effects on domestic and global food provision, resource use, nitrogen and phosphorus losses, and greenhouse gas (GHG) emissions. We provide a comprehensive analysis of the driving forces around this transition and its national and global consequences. The number of livestock units (LUs) tripled in China in less than 30 years, mainly through the growth of landless industrial livestock production systems and the increase in monogastric livestock (from 62 to 74% of total LUs). Changes were fueled through increases in demand as well as, supply of new breeds, new technology, and government support. Production of animal source protein increased 4.9 times, nitrogen use efficiency at herd level tripled, and average feed use and GHG emissions per gram protein produced decreased by a factor of 2 between 1980 and 2010. In the same period, animal feed imports have increased 49 times, total ammonia and GHG emissions to the atmosphere doubled, and nitrogen losses to watercourses tripled. As a consequence, China’s livestock transition has significant global impact. Forecasts for 2050, using the Shared Socio-economic Pathways scenarios, indicate major further changes in livestock production and impacts. On the basis of these possible trajectories, we suggest an alternative transition, which should be implemented by government, processing industries, consumers, and retailers. This new transition is targeted to increase production efficiency and environmental performance at system level, with coupling of crop-livestock production, whole chain manure management, and spatial planning as major components.

B Vitamins Can Reduce Body Weight Gain by Increasing Metabolism-related Enzyme Activities in Rats Fed on a High-Fat Diet
Zheng, Ying ; Ma, A. ; Zheng, Ming C. ; Wang, Qiuzhen ; Liang, Hui ; Han, Xiuxia ; Schouten, Evert G. - \ 2018
Current Medical Science 38 (2018)1. - ISSN 2096-5230 - p. 174 - 183.
B vitamins - body weight gain - enzyme activities - obesity - rats

B vitamins are enzyme cofactors that play an important role in energy metabolism. The aim of this study was to elucidate whether B vitamin administration can reduce body weight (BW) gain by improving energy metabolism-related enzyme activities in rats fed on a highfat diet. Fifty rats were randomly assigned to one of the following five groups: control group (C), including rats fed on standard rat chow; four treatment groups (HO, HI, H2, and H3), in which rats were fed on a high-fat diet. Rats in the HI group were treated daily with 100 mg/kg BW thiamine (VB1), 100 mg/kg BW riboflavin (VB2), and 250 mg/kg BW niacin (VPP); rats in the H2 group were treated daily with 100 mg/kg BW pyridoxine (VB6), 100 mg/kg BW cobalamin (VB12), and 5 mg/kg BW folate (FA); and rats in the H3 group were treated daily with all of the B vitamins administered to the HI and H2 groups. After 12 weeks, the BW gains from the initial value were 154.5±58.4 g and 159.1±53.0 g in the HI and C groups, respectively, which were significantly less than the changes in the HO group (285.2±14.8 g, P<0.05). In the HO group, the plasma total cholesterol (CHO) and triglyceride (TG) levels were 1.59±0.30 mmol/L and 1,55±0.40 mmol/L, respectively, which were significantly greater than those in the HI group (1.19±0.18 mmol/L and 0.76±0.34 mmol/L, respectively, P<0.05). The activities of transketolase (TK), glutathione reductase, and Na+/K+ adenosine triphosphatase were significantly increased in the B vitamin-treated groups and were significantly greater than those in the HO group (P<0.05). Furthermore, the glucose-6-phosphate dehydrogenase, pyruvic acid kinase, and succinate dehydrogenase activities also were increased after treatment with B vitamins. Supplementation with B vitamins could effectively reduce BW gain and plasma levels of lipids by improving energy metabolism-related enzyme activities in rats, thus possibly providing potential benefits to humans.

Review: the energetic value of zooplankton and nekton species of the Southern Ocean
Schaafsma, Fokje L. ; Cherel, Yves ; Flores, Hauke ; Franeker, Jan Andries Van; Lea, M.A. ; Raymond, Ben ; De Putte, Anton P. Van - \ 2018
Marine Biology 165 (2018). - ISSN 0025-3162 - 39 p.
Understanding the energy flux through food webs is important for estimating the capacity of marine ecosystems to support stocks of living resources. The energy density of species involved in trophic energy transfer has been measured in a large number of small studies, scattered over a 40-year publication record. Here, we reviewed energy density records of Southern Ocean zooplankton, nekton and several benthic taxa, including previously unpublished data. Comparing measured taxa, energy densities were highest in myctophid fishes (ranging from 17.1 to 39.3 kJ g−1 DW), intermediate in crustaceans (7.1
to 25.3 kJ g−1 DW), squid (16.2 to 24.0 kJ g−1 DW) and other fish families (14.8 to 29.9 kJ g−1 DW), and lowest in jelly fish (10.8 to 18.0 kJ g−1 DW), polychaetes (9.2 to 14.2 kJ g−1 DW) and chaetognaths (5.0–11.7 kJ g−1 DW). Data reveals differences in energy density within and between species related to size, age and other life cycle parameters. Important taxa in Antarctic food webs, such as copepods, squid and small euphausiids, remain under-sampled. The variability in energy density of Electrona antarctica was likely regional rather than seasonal, although for many species with limited data it remains difficult to disentangle regional and seasonal variability. Models are provided to estimate energy density more quickly using a species’ physical parameters. It will become increasingly important to close knowledge gaps to improve the ability of bioenergetic and food web models to predict changes in the capacity of Antarctic ecosystems to support marine life.
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