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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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. - \ 2019
Agricultural and Forest Meteorology 264 (2019). - ISSN 0168-1923 - p. 351 - 362.
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.

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. - \ 2019
Ticks and Tick-borne Diseases 10 (2019)1. - ISSN 1877-959X - p. 128 - 131.
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.

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.

The EU food and drink industry use of domestic raw material
Logatcheva, K. ; Galen, M.A. van - \ 2018
Den Haag : Wageningen Economic Research (Fact sheet Wageningen Economic Research 2018-086) - 8 p.
European training consortium public health and health promotion : 27 years achieving the IUHPE competencies
Bonmati, A. ; Vaandrager, L. ; Contu, P. ; Massanoti, G. ; Kennedy, L. ; Lindström, B. ; Ortiz, G. ; Alvarez-Dardet, C. ; Poccetta, G. ; Boonekamp, G. ; Hofmeister, Arnd ; Fosse, Elisabeth ; Wrzesinska, M. ; Juvinya, Dolors ; Breton, Eric ; Pavlekovic, G. ; Koelen, M.A. - \ 2018
Exploring practice based theories for health promotion among families with low socio-economic status
Hogeling, L. ; Crijns-Lammers, Christianne ; Vaandrager, L. ; Koelen, M.A. - \ 2018
Dry fractionation of quinoa sweet varieties Atlas and Riobamba for sustainable production of protein and starch fractions
Opazo Navarrete, M.A. ; Tagle Freire, Danny ; Boom, R.M. ; Janssen, A.E.M. ; Schutyser, M.A.I. - \ 2018
Journal of Food Composition and Analysis 74 (2018). - ISSN 0889-1575 - p. 95 - 101.
Dry milling and subsequent sieving were evaluated as an alternative to the conventional wet extraction of quinoa (Chenopodium quinoa Willd.) proteins and starch. Specifically, quinoa sweet varieties have the potential to be dry fractionated. Dry fractionation of quinoa is an alternative and more sustainable route for producing protein-enriched and starch fractions than conventionally wet fractionation. Quinoa seeds were subjected to coarse grinding and subsequently sieved using different sizes of sieves to obtain fractions enriched in protein and starch. The protein-enriched fractions contained ∼32% proteins (32 g/100 g dry solids) while the starch-rich fractions contained 86–89% starch (86–89 g/100 g dry solids). The quinoa fractions were characterised and compared to wet-isolated starch and protein. The gelatinization temperature of the starch-rich fraction was influenced by the residual presence of proteins. The starch-rich fraction also had different pasting properties than starch isolate. The unheated protein-enriched fractions showed high water retention capacity and solubility, which could be potentially interesting to apply in gluten-free products.
Dynamics of the Phanerochaete carnosa transcriptome during growth on aspen and spruce
Jurak, E. ; Suzuki, H. ; Erven, G. van; Gandier, J.A. ; Wong, P. ; Chan, K. ; Ho, C.Y. ; Gong, Y. ; Tillier, E. ; Rosso, M.N. ; Kabel, M.A. ; Miyauchi, S. ; Master, E.R. - \ 2018
BMC Genomics 19 (2018)1. - ISSN 1471-2164
Carbohydrate active enzymes - Hydrophobins - Lignocellulose conversions - Loosenins - Phanerochaete carnosa - Transcriptomics

BACKGROUND: The basidiomycete Phanerochaete carnosa is a white-rot species that has been mainly isolated from coniferous softwood. Given the particular recalcitrance of softwoods to bioconversion, we conducted a comparative transcriptomic analysis of P. carnosa following growth on wood powder from one softwood (spruce; Picea glauca) and one hardwood (aspen; Populus tremuloides). P. carnosa was grown on each substrate for over one month, and mycelia were harvested at five time points for total RNA sequencing. Residual wood powder was also analyzed for total sugar and lignin composition. RESULTS: Following a slightly longer lag phase of growth on spruce, radial expansion of the P. carnosa colony was similar on spruce and aspen. Consistent with this observation, the pattern of gene expression by P. carnosa on each substrate converged following the initial adaptation. On both substrates, highest transcript abundances were attributed to genes predicted to encode manganese peroxidases (MnP), along with auxiliary activities from carbohydrate-active enzyme (CAZy) families AA3 and AA5. In addition, a lytic polysaccharide monooxygenase from family AA9 was steadily expressed throughout growth on both substrates. P450 sequences from clans CPY52 and CYP64 accounted for 50% or more of the most highly expressed P450s, which were also the P450 clans that were expanded in the P. carnosa genome relative to other white-rot fungi. CONCLUSIONS: The inclusion of five growth points and two wood substrates was important to revealing differences in the expression profiles of specific sequences within large glycoside hydrolase families (e.g., GH5 and GH16), and permitted co-expression analyses that identified new targets for study, including non-catalytic proteins and proteins with unknown function.

Effect of soil management on soil erosion on sloping farmland during crop growth stages under a large-scale rainfall simulation experiment
Wang, Linhua ; Wang, Yafeng ; Saskia, Keesstra ; Artemi, Cerdà ; Ma, Bo ; Wu, Faqi - \ 2018
Journal of Arid Land 10 (2018)6. - ISSN 1674-6767 - p. 921 - 931.
crop growth stages - hoeing tillage - Loess Plateau - simulated rainfall - soil erosion

Soil erosion on farmland is a critical environmental issue and the main source of sediment in the Yellow River, China. Thus, great efforts have been made to reduce runoff and soil loss by restoring vegetation on abandoned farmland. However, few studies have investigated runoff and soil loss from sloping farmland during crop growth season. The objective of this study was to investigate the effects of soil management on runoff and soil loss on sloping farmland during crop growth season. We tested different soybean growth stages (i.e., seedling stage (R1), initial blossoming stage (R2), full flowering stage (R3), pod bearing stage (R4), and initial filling stage (R5)) and soil management practice (one plot applied hoeing tillage (HT) before each rainfall event, whereas the other received no treatment (NH)) by applying simulated rainfall at an intensity of 80 mm/h. Results showed that runoff and soil loss both decreased and infiltration amount increased in successive soybean growth stages under both treatments. Compared with NH plot, there was less runoff and higher infiltration amount from HT plot. However, soil loss from HT plot was larger than that from NH plot in R1–R3, but lower in R4 and R5. In the early growth stages, hoeing tillage was effective for reducing runoff and enhancing rainfall infiltration. By contrast, hoeing tillage enhanced soil and water conservation during the late growth stages. The total soil loss from HT plot (509.0 g/m2) was 11.1% higher than that from NH plot (457.9 g/m2) in R1–R5. However, the infiltration amount from HT plot (313.9 mm) was 18.4% higher than that from NH plot (265.0 mm) and the total runoff volume from HT plot was 49.7% less than that from NH plot. These results indicated that crop vegetation can also act as a type of vegetation cover and play an important role on sloping farmland. Thus, adopting rational soil management in crop planting on sloping farmland can effectively reduce runoff and soil loss, as well as maximize rainwater infiltration during crop growth period.

Analysis of drought and vulnerability in the North Darfur region of Sudan
Mohmmed, Alnail ; Zhang, Ke ; Kabenge, Martin ; Keesstra, Saskia ; Cerdà, Artemi ; Reuben, Makomere ; Elbashier, Mohammed M.A. ; Dalson, Twecan ; Ali, Albashir A.S. - \ 2018
Land Degradation and Development (2018). - ISSN 1085-3278
drought - meteorology - North Darfur region - remote sensing - vulnerability index

North Darfur of Sudan is located on the edge of the Sahara Desert and endures frequent droughts due to water shortages and high summer temperatures. Monitoring and understanding drought characteristics are essential for integrated drought risk mitigation and prevetion of land degradation. This study evaluates drought conditions in North Darfur by analyzing the spatiotemporal distribution of drought using three drought indices (Standardized Precipitation Index, Vegetation Condition Index, and Soil Moisture Content Index) and their combined drought index (CDI) from 2004 to 2013. Biophysical and socioeconomic indicators are further used to measure vulnerability to drought risk and its three components (exposure, sensitivity, and adaptive capacity) through a comprehensive risk assessment framework. The results show that most of North Darfur has experienced prolonged droughts during the study period, especially from 2007 to 2011. There is also a significant correlation between the monsoon season CDI and annual crop yield anomaly. The results confirm the validity of the CDI index, which provides a comprehensive description of the drought situation by combing four drought indices quantifying different drought aspects. The vulnerability results show that the majority of this region is highly exposed and sensitive to drought risks. In particular, the northern zone of the region is highly vulnerable, which is categorized by less-crop diversity, higher land degradation, frequent droughts, and high-poverty levels. This study provides valuable information for coping with climate change-induced drought risk in this region and demonstrates that there is still a large room for enhancing the adaptation capacity in this region.

Experiences in deriving and implementing Specific Protection Goal options in the EFSA Aquatic Guidance Document
Brock, T.C.M. - \ 2018
In: Summary Report of Joint VKM and EFSA Symposium on risk assessment and risk management cooperation on environmental protection goals / Finne, M.A., Wendell, M., EFSA (EFSA Supporting Publications 4) - p. 14 - 15.
The Norwegian Scientific Committee for Food and Environment in collaboration with the European Food Safety Authority organised a symposium on risk assessment and risk management cooperation on environmental protection goals in Oslo in October 2017. The Symposium gather together more than 155 academics, risk assessors, risk managers, representatives from governmental agencies, industry, and NGOs from all over Europe. Maintaining biodiversity is one of the key protection goals referred to in different legislative frameworks. Biodiversity is, however, a very broad term when considered in a risk assessment and subsequent risk management context. Specifying particular components of biodiversity that need protection, for example specific species or ecological processes, will define the framework in which risk assessors operate when performing Environmental Risk Assessments (ERAs), and provide more practical, specific protection goals (SPGs) for risk managers. In 2016, EFSA issued guidance on how to derive SPGs for use in ERAs. The aim of the guidance is to provide a harmonised methodological framework using the ecosystem services (ES) concept to derive practical, specific environmental protection goals, regardless of the regulated product or organism that is being assessed. It is imperative that risk assessors and risk managers are encouraged to be in close dialogue when defining SPGs, because setting the level of protection involves normative considerations that cannot be accounted for by risk assessors alone. The symposium aimed to facilitate and encourage dialogue and cooperation on protection goals between risk assessors and risk managers, and to present the EFSA guidance to develop protection goals options for use in ERA. This publication reports on the presentations, discussions and recommendations made during the symposium.
Movement patterns of African Elephants (Loxodonta africana) in a Semi-arid Savanna suggest that they have information on the location of dispersed water sources
Wato, Yussuf A. ; Prins, Herbert H.T. ; Heitkönig, Ignas M.A. ; Wahungu, Geoffrey M. ; Ngene, Shadrack M. ; Njumbi, Steve ; Langevelde, Frank van - \ 2018
Frontiers in Ecology and Evolution 6 (2018)OCT. - ISSN 2296-701X
Conservation - Directionality - Movement - Savanna - Step length - Tsavo - Wildlife

Water is a scarce resource in semi-arid savannas where over half of the African elephants (Loxodonta africana) populations occur and may therefore influence their movement pattern. A random search is expected for an animal with no information on the location of the target resource, else, a direction-oriented walk is expected. We hypothesized that elephants movement patterns show a stronger directional orientation toward water sources in the dry season compared to the wet season. We investigated the movement paths of four male and four female elephants with hourly GPS fixes in Tsavo National Park, Kenya in 2012-2013. Consistent with our predictions, the movement paths of elephants had longer step lengths, longer squared net displacements, and were directed toward water sources in the dry season as compared to the wet season. We argue that African elephants know the location of dispersed water resources, enabling them to survive with scarce resources in dry savannas. These results can be used in conservation and management of wildlife, through for instance, protection of preferred water sources.

Mechanistic insight in the selective delignification of wheat straw by three white-rot fungal species through quantitative 13C-IS py-GC–MS and whole cell wall HSQC NMR
Erven, G. van; Nayan, Nazri ; Sonnenberg, A.S.M. ; Hendriks, W.H. ; Cone, J.W. ; Kabel, M.A. - \ 2018
Biotechnology for Biofuels 11 (2018). - ISSN 1754-6834 - 16 p.
Ceriporiopsis subvermispora - Lentinula edodes - pleurotus eryngii - Selectivity - Lignin degradation - Lignin quantification - Cα-oxidation - Ligninolytic enzymes
Background The white-rot fungi Ceriporiopsis subvermispora (Cs), Pleurotus eryngii (Pe), and Lentinula edodes (Le) have been shown to be high-potential species for selective delignification of plant biomass. This delignification improves polysaccharide degradability, which currently limits the efficient lignocellulose conversion into biochemicals, biofuels, and animal feed. Since selectivity and time efficiency of fungal delignification still need optimization, detailed understanding of the underlying mechanisms at molecular level is required. The recently developed methodologies for lignin quantification and characterization now allow for the in-depth mapping of fungal modification and degradation of lignin and, thereby, enable resolving underlying mechanisms. Results Wheat straw treated by two strains of Cs (Cs1 and Cs12), Pe (Pe3 and Pe6) and Le (Le8 and Le10) was characterized using semi-quantitative py-GC–MS during fungal growth (1, 3, and 7 weeks). The remaining lignin after 7 weeks was quantified and characterized using 13C lignin internal standard based py-GC–MS and whole cell wall HSQC NMR. Strains of the same species showed similar patterns of lignin removal and degradation. Cs and Le outperformed Pe in terms of extent and selectivity of delignification (Cs ≥ Le >> Pe). The highest lignin removal [66% (w/w); Cs1] was obtained after 7 weeks, without extensive carbohydrate degradation (factor 3 increased carbohydrate-to-lignin ratio). Furthermore, though after treatment with Cs and Le comparable amounts of lignin remained, the structure of the residual lignin vastly differed. For example, Cα-oxidized substructures accumulated in Cs treated lignin up to 24% of the total aromatic lignin, a factor two higher than in Le-treated lignin. Contrarily, ferulic acid substructures were preferentially targeted by Le (and Pe). Interestingly, Pe-spent lignin was specifically depleted of tricin (40% reduction). The overall subunit composition (H:G:S) was not affected by fungal treatment. Conclusions Cs and Le are both able to effectively and selectively delignify wheat straw, though the underlying mechanisms are fundamentally different. We are the first to identify that Cs degrades the major β-O-4 ether linkage in grass lignin mainly via Cβ–O–aryl cleavage, while Cα–Cβ cleavage of inter-unit linkages predominated for Le. Our research provides a new insight on how fungi degrade lignin, which contributes to further optimizing the biological upgrading of lignocellulose.
Occupancy strongly influences faecal microbial composition of wild lemurs
Umanets, Alexander ; Winter, Iris de; IJdema, Freek ; Ramiro-Garcia, Javier ; Hooft, Pim van; Heitkönig, Ignas M.A. ; Prins, Herbert H.T. ; Smidt, Hauke - \ 2018
FEMS Microbiology Ecology 94 (2018)3. - ISSN 0168-6496
Environment - Eulemur - Gastro-intestinal tract - Madagascar - Microbiota - Multivariate statistics

The microbiota of the mammalian gut is a complex ecosystem, the composition of which is greatly influenced by host genetics and environmental factors. In this study, we aim to investigate the influence of occupancy (a geographical area of habitation), species, age and sex on intestinal microbiota composition of the three lemur species: Eulemur fulvus, E. rubriventer and E. rufifrons. Faecal samples were collected from a total of 138 wild lemurs across Madagascar, and microbial composition was determined using next-generation sequencing of PCR-amplified 16S rRNA gene fragments. Consistent with reports from other primate species, the predominant phyla were Firmicutes (43 ± 6.4% [s.d.]) and Bacteroidetes (30.3 ± 5.3%). The microbial composition was strongly associated with occupancy in the E. fulvus population, with up to 19.9% of the total variation in microbial composition being explained by this factor. In turn, geographical differences observed in faecal microbiota of sympatric lemur species were less pronounced, as was the impact of the factors sex and age. Our findings showed that among the studied factors occupancy had the strongest influence on intestinal microbiota of congeneric lemur species. This suggests adaptation of microbiota to differences in forest composition, climate variations and correspondingly available diet in different geographical locations of Madagascar.

Bespuiting succesvol tegen maïsstengelboorder
Groten, Jos - \ 2018
Nutrient use efficiencies, losses, and abatement strategies for peri-urban dairy production systems
Wei, S. ; Bai, Z.H. ; Qin, W. ; Wu, Z.G. ; Jiang, R.F. ; Ma, L. - \ 2018
Journal of Environmental Management 228 (2018). - ISSN 0301-4797 - p. 232 - 238.
Dairy farms - Manure management - Nitrogen - NUFER model - Nutrient cycling - Phosphorus

Manure management is an important aspect of urban livestock production that has a profound impact on metropolitan living. Data were collected from 28 dairy farms in peri-urban Beijing and analysed to determine farm nitrogen and phosphorus flows and costs associated with various manure management options to reduce nutrient losses. Dairy production in peri-urban Beijing was characterized by its use of high protein diets (16.3–17.0% crude protein), high reliance on imported feeds (92–98%), and low manure recycling (3.0–10.8%). Farms of 900–2000 cattle showed lower use efficiencies than farms of <900 cattle. Costs of manure handling ranged from 0.1 to 1.0 Yuan kg−1 milk. Among various manure treatment options, biogas digesters with aerobic lagoons had the lowest N losses and costs, justifying their investments. In conclusion, peri-urban dairy production systems were contrasting with traditional systems and within their own systems in nutrient use efficiency and losses, which was mainly decided by their farm size. To improve the nutrient use efficiencies and reduce losses, farmers and managers of peri-urban dairy production system should have a full awareness of different feed intake and manure management.

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.

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