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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Exploiting the Spur of the Moment to Enhance Healthy Consumption: Verbal Prompting to Increase Fruit Choices in a Self-Service Restaurant
Kleef, E. van; Broek, O. van den; Trijp, J.C.M. van - \ 2015
Applied Psychology : Health and Well-Being 7 (2015)2. - ISSN 1758-0846 - p. 149 - 166.
safety-belt use - field-experiment - vegetable intake - strategies - consumers - children - behavior - sales - risk
Background: People often have good intentions to eat healthily, but these inten- tions may get overruled by temporary moments of temptation. The current study examined the effectiveness of “verbal prompting” as a nudge to increase fruit salad sales in a natural setting. Methods: A ¿eld experiment was conducted in a self- service restaurant during breakfast time. After an initial baseline period, the inter- vention involved four different prompts suggesting ordering a side dish (i.e. orange juice, fruit salad, pancakes) given by cashiers to visitors. The intervention phase lasted 13 weeks. Cash register and observational data were obtained. In addition, a sample of visitors (N = 393) responded to a survey. Results: A signi¿cant increase in sales of orange juice was observed during the orange juice verbal prompts intervention periods (35–42% of all breakfasts sold) compared to baseline (20% of all breakfasts sold). Similarly, sales of fruit salad (9%) and pancakes (3%) rose to a small but signi¿cant extent compared to baseline sales (3% and 1%, respectively). Survey results showed that customers did not feel pressurised into purchasing a side dish. Conclusion: Together, ¿ndings suggest that verbal prompts involving healthy side dishes are a potential useful nudge to implement in other food service settings. Keywords: choice architecture, fruit consumption, nudge, nudging, suggestive selling, verbal prompting
Experimental evidence for inherent Lévy search behaviour in foraging animals
Kölzsch, A. ; Alzate, A. ; Bartumeus, F. ; Jager, M. de; Weerman, E.J. ; Hengeveld, G.M. ; Naguib, M. ; Nolet, B.A. ; Koppel, J. van de - \ 2015
Proceedings of the Royal Society. B: Biological Sciences 282 (2015)1807. - ISSN 0962-8452 - 9 p.
correlated-random-walks - environmental complexity - wandering albatrosses - movement patterns - marine predator - flight - strategies - success - evolve - scale
Recently, Lévy walks have been put forward as a new paradigm for animal search and many cases have been made for its presence in nature. However, it remains debated whether Lévy walks are an inherent behavioural strategy or emerge from the animal reacting to its habitat. Here, we demonstrate signatures of Lévy behaviour in the search movement of mud snails (Hydrobia ulvae) based on a novel, direct assessment of movement properties in an experimental set-up using different food distributions. Our experimental data uncovered clusters of small movement steps alternating with long moves independent of food encounter and landscape complexity. Moreover, size distributions of these clusters followed truncated power laws. These two findings are characteristic signatures of mechanisms underlying inherent Lévy-like movement. Thus, our study provides clear experimental evidence that such multi-scale movement is an inherent behaviour rather than resulting from the animal interacting with its environment.
Intensive groundwater use and (in)equity: Processes and governance challenges
Hoogesteger van Dijk, J.D. ; Wester, P. - \ 2015
Environmental Science & Policy 51 (2015). - ISSN 1462-9011 - p. 117 - 124.
water - policies - india - sustainability - organizations - irrigation - strategies - management - highlands - depletion
Groundwater forms the basis for millions of rural and urban livelihoods around the world. Building on insights from the theory of access, in this article we present how groundwater development has brought much well-fare in many parts of the world; and how resulting intensive groundwater use is leading to ill-fare through aquifer overexploitation and processes of water accumulation and dispossession. We show the difficulty of state regulation and the modest achievements of other governance approaches that aim to solve existing groundwater problems. To study these processes we propose a framework of analysis that is based on the study of hydrosocial-networks, the political economy of groundwater and the domains and discourses that define groundwater access. Such analysis highlights the challenges of devising policies and modes of governance that contribute to social and environmental sustainability in intensively used aquifers. These we argue should build on an analysis of equity that scrutinizes the discourses, actors, powers and procedures that define groundwater access. By inciting debates on equity a first and fundamental step can be made toward advancing more inclusive groundwater governance that crucially engages the marginalized and addresses their groundwater problems, concerns and needs.
Economic trade-offs of biomass use in crop-livestock systems: Exploring more sustainable options in semi-arid Zimbabwe
Homann Kee, S. ; Valbuena Vargas, D.F. ; Masikati, P. ; Descheemaeker, K.K.E. ; Nyamangara, J. ; Claessens, L.F.G. ; Erenstein, O. ; Rooyen, A.F. van; Nkomboni, D. - \ 2015
Agricultural Systems 134 (2015). - ISSN 0308-521X - p. 48 - 60.
conservation agriculture - smallholder farmers - intensification - productivity - challenges - strategies - countries - benefits - tropics - africa
In complex mixed crop-livestock systems with limited resources and biomass scarcity, crop residues play an important but increasingly contested role. This paper focuses on farming systems in the semi-arid areas of Zimbabwe, where biomass production is limited and farmers integrate crop and livestock activities. Conservation Agriculture (CA) is promoted to intensify crop production, emphasizing the retention of surface mulch with crop residues (CR). This paper quantifies the associated potential economic tradeoffs and profitability of using residues for soil amendment or as livestock feed, and explores alternative biomass production options. We draw on household surveys, stakeholder feedback, crop, livestock and economic modeling tools. We use the Trade-Off Analysis Model for Multi Dimensional Impact Assessment (TOA-MD) to compare different CR use scenarios at community level and for different farm types: particularly the current base system (cattle grazing of maize residues) and sustainable intensification alternatives based on a CA option (mulching using maize residues ± inorganic fertilizer) and a maize– mucuna (Mucuna pruriens) rotation. Our results indicate that a maize–mucuna rotation can reduce trade-offs between CR uses for feed and mulch, providing locally available organic soil enhancement, supplementary feed and a potential source of income. Conservation Agriculture without fertilizer application and at non-subsidized fertilizer prices is not financially viable; whereas with subsidized fertilizer it can benefit half the farm population. The poverty effects of all considered alternative biomass options are however limited; they do not raise income sufficiently to lift farmers out of poverty. Further research is needed to establish the competitiveness of alternative biomass enhancing technologies and the socio-economic processes that can facilitate sustainable intensification of mixed crop-livestock systems, particularly in semi-arid environments.
Navigating the obesogenic environment: How psychological sensitivity to the food environment and self-regulatory competence are associated with adolescent unhealthy snacking
Stok, F.M. ; Vet, E. de; Wardle, J. ; Chu, M.T. ; Wit, J.B.F. ; Ridder, D.T.D. de - \ 2015
Eating Behaviors 17 (2015). - ISSN 1471-0153 - p. 19 - 22.
health consequences - obesity - gratification - strategies - overweight - worldwide - autonomy - children - adults - scale
Purpose: Living in an obesogenic environment may not affect all adolescents to the same extent, depending on their psychological sensitivity to the food environment and their self-regulatory competence. The purpose of the current study was to examine associations of these two factors with unhealthy snacking among adolescents. We also investigated whether self-regulatory competence could attenuate the negative effects of being sensitive to the food environment. Methods: A survey was completed by 11,392 European adolescents (10–17 years old). The survey measured psychological sensitivity to the food environment, self-regulatory competence and self-reported unhealthy snack intake. Results: Higher food environment sensitivity and lower self-regulatory competence were associated with more unhealthy snacking. The two factors also interacted, with self-regulatory competence attenuating the influence of high food environment sensitivity. Discussion: Adolescentswho are sensitive to the food environment reported higher unhealthy snack intake.More frequent use of self-regulation strategies on the other hand was associated with lower unhealthy snack intake. Moreover, self-regulatory competence was found to moderate the influence of psychological sensitivity to the food environment on unhealthy snacking, although the effect size was small. Fostering adolescents' self-regulatory competence can help enable them to better navigate the obesogenic environment.
Fitness consequences of indirect plant defence in the annual weed, Sinapis arvensis
Gols, R. ; Wagenaar, R. ; Poelman, E.H. ; Kruidhof, H.M. ; Loon, J.J.A. van; Harvey, J.A. - \ 2015
Functional Ecology 29 (2015)8. - ISSN 0269-8463 - p. 1019 - 1025.
pieris-brassicae - herbivory - tolerance - evolution - volatiles - insects - parasitoids - strategies - selection - ecology
Plant traits that enhance the attraction of the natural enemies of their herbivores have been postulated to function as an 'indirect defence'. An important underlying assumption is that this enhanced attraction results in increased plant fitness due to reduced herbivory. This assumption has been rarely tested. We investigated whether there are fitness consequences for the charlock mustard Sinapis arvensis, a short-lived outcrossing annual weedy plant, when exposed to groups of large cabbage white (Pieris brassicae) caterpillars parasitized by either one of two wasp species, Hyposoter ebeninus and Cotesia glomerata, that allow the host to grow during parasitism. Hyposoter ebeninus is solitary and greatly reduces host growth compared with healthy caterpillars, whereas C. glomerata is gregarious and allows the host to grow approximately as large as unparasitized caterpillars. Both healthy and parasitized P. brassicae caterpillars initially feed on the foliage, but later stages preferentially consume the flowers. In a garden experiment, plants damaged by parasitized caterpillars produced more seeds than conspecific plants damaged by unparasitized caterpillars. Reproductive potential (germination success multiplied by total seed number) was similar for plants that were not exposed to herbivory and those that were damaged by parasitized caterpillars and lower for plants that were damaged by healthy unparasitized caterpillars. However, these quantitative seed traits negatively correlated with the qualitative seed traits, individual seed size and germination success, suggesting a trade-off between these two types of traits. We show that parasitism of insect herbivores that feed on reproductive plant tissues may have positive fitness consequences for S. arvensis. The extent to which plant fitness may benefit depends on parasitoid lifestyle (solitary or gregarious), which is correlated with the amount of damage inflicted on these tissues by the parasitized host
Climate change impact and adaptation research requires integrated assessment and farming systems analysis: a case study in the Netherlands
Reidsma, P. ; Wolf, J. ; Kanellopoulos, A. ; Schaap, B.F. ; Mandryk, M. ; Verhagen, J. ; Ittersum, M.K. van - \ 2015
Environmental Research Letters 10 (2015)4. - ISSN 1748-9326
european-union - crop yields - agriculture - responses - models - wheat - variability - improvement - strategies - scenarios
Rather than on crop modelling only, climate change impact assessments in agriculture need to be based on integrated assessment and farming systems analysis, and account for adaptation at different levels. With a case study for Flevoland, the Netherlands, we illustrate that (1) crop models cannot account for all relevant climate change impacts and adaptation options, and (2) changes in technology, policy and prices have had and are likely to have larger impacts on farms than climate change. While crop modelling indicates positive impacts of climate change on yields of major crops in 2050, a semiquantitative and participatory method assessing impacts of extreme events shows that there are nevertheless several climate risks. A range of adaptation measures are, however, available to reduce possible negative effects at crop level. In addition, at farm level farmers can change cropping patterns, and adjust inputs and outputs. Also farm structural change will influence impacts and adaptation. While the 5th IPCC report is more negative regarding impacts of climate change on agriculture compared to the previous report, also for temperate regions, our results show that when putting climate change in context of other drivers, and when explicitly accounting for adaptation at crop and farm level, impacts may be less negative in some regions and opportunities are revealed. These results refer to a temperate region, but an integrated assessment may also change perspectives on climate change for other parts of the world.
Does temperament affect learning in calves?
Webb, L.E. ; Reenen, C.G. van; Jensen, M.B. ; Schmitt, O. ; Bokkers, E.A.M. - \ 2015
Applied Animal Behaviour Science 165 (2015). - ISSN 0168-1591 - p. 33 - 39.
individual coping characteristics - different rooting materials - double demand curves - inbred rat strains - cross-point - animal preferences - yearling horses - heifer calves - pigs - strategies
The aim of the study was to investigate how temperament affects learning ability in calves.Nine two-month-old Holstein-Friesian bull calves were subjected to four challenge tests:novel object (NOT), novel environment (NET), social isolation (SIT), and social isolationwith a novel environmental cue (SI/E). During these tests, hypothesised temperament vari-ables were recorded. Hypothesised learning variables were recorded during training on anoperant task.Principal component analysis (PCA) was conducted on temperament variables and learn-ing variables separately. Principal components (PCs) hypothesised to reflect underlyingtemperament and learning traits were extracted from these two PCAs using the Kaiserrule. Spearman’s rank correlations were carried out to determine relationships betweentemperament and learning PC scores.Four temperament PCs were extracted from the PCA on temperament variables, andthese were proposed to reflect fearfulness, activity, exploration, and attention towards theenvironment. These hypothesised underlying temperamental traits were consistent withfindings of previous studies using larger numbers of calves. Two learning PCs were extractedfrom the PCA on learning variables, and these were proposed to reflect feed motivationand working speed. A single correlation was found between temperament and learning PCscores: high activity was associated with low feed motivation. This preliminary exploratorystudy suggests that temperament, as assessed during challenge tests, may affect learningan operant conditioning task in calves. Understanding how temperament affects learningin calves can help with the training of calves on novel automated feeding apparatuses oron novel feed components, and can thus help improve calf health and welfare.
Organizing Products with Complements versus Substitutes: Effects on Store Preferences as a Function of Effort and Assortment Perceptions
Diehl, K. ; Herpen, E. van; Lamberton, C. - \ 2015
Journal of Retailing 91 (2015)1. - ISSN 0022-4359 - p. 1 - 18.
consumer choice - price sensitivity - purchase - variety - behavior - too - organization - recognition - elasticity - strategies
Retailers often organize at least part of their assortment by displaying complementary products from different product categories together (e.g., a pair of pants with a shirt) rather than grouping items by product type (e.g., a pair of pants with other pants). However, little is known about how retailers should choose between complement-based and substitute-based organizations. The present paper shows that consumers’ preferences for such store organizations are a function of the effort and assortment perceptions cued by these organizational formats. Holding the underlying assortment constant, complement-based organizations are always more effortful than substitute-based organizations. This difference in effort can create downward pressure on complement-based store choice. Moreover, the effects of organization format on assortment perception depend on whether consumers hold a hedonic or utilitarian focus. When consumers have a highly hedonic focus, complement-based based stores create more positive assortment perceptions than substitute-based stores. Such positive assortment perceptions can, in turn, raise complement-based store choice. However, as consumers’ utilitarian focus increases, substitute-based assortments are seen as both easier and more attractive, leading to a strong advantage in store choice. Our findings provide actionable guidance for retailers considering various store organizations and suggest opportunities for future research.
Evolutionary engineering to enhance starter culture performance in food fermentations
Bachmann, H. ; Pronk, J.T. ; Kleerebezem, M. ; Teusink, B. - \ 2015
Current Opinion in Biotechnology 32 (2015). - ISSN 0958-1669 - p. 1 - 7.
yeast saccharomyces-cerevisiae - adaptive evolution - lactococcus-lactis - hyperosmotic conditions - selection - growth - population - strategies - phenotypes - stability
Microbial starter cultures are essential for consistent product quality and functional properties such as flavor, texture, pH or the alcohol content of various fermented foods. Strain improvement programs to achieve desired properties in starter cultures are diverse, but developments in next-generation sequencing lead to an increased interest in evolutionary engineering of desired phenotypes. We here discuss recent developments of strain selection protocols and how computational approaches can assist such experimental design. Furthermore the analysis of evolved phenotypes and possibilities with complex consortia are highlighted. Studies carried out with mainly yeast and lactic acid bacteria demonstrate the power of evolutionary engineering to deliver strains with novel phenotypes as well as insight into underlying mechanisms.
Dark green electricity comes from the sea: Capitalizing on ecological merits of offshore wind power?
Toonen, H.M. ; Lindeboom, H.J. - \ 2015
Renewable and Sustainable Energy Reviews 42 (2015). - ISSN 1364-0321 - p. 1023 - 1033.
sustainable fisheries - energy - policy - farms - governance - management - strategies - responses - impacts - germany
European consumers are willing to pay more for “green” electricity, as they highly value renewable energy sources for the contribution to combating climate change. There is a push for getting higher levels of sustainability, leading to a differentiation of Europe‘s electricity market. In this differentiation, the large potential of wind energy is recognized. More specifically, North Sea countries prefer to plan wind arrays (far) out at sea. This article offers a review of the main arguments for offshore wind energy, described in comparison with its onshore counterpart. It is stated that offshore wind farms (OWFs) generate “dark green” electricity as they mitigate greenhouse gas emissions and contribute to the protection of (some) marine life. Applying an informational governance framework, this article further assesses whether this dark green message has been exploited through further differentiation of the electricity market, and provides an analysis of why this is not (yet) the case. It is concluded that the dominant discourse in onshore wind power development hinders a favorable ecological differentiation toward offshore wind power.
The impact of domestic energy efficiency retrofit schemes on householder attitudes and behaviours
Long, T.B. ; Young, W. ; Webber, P. ; Gouldson, A. ; Harwatt, H. - \ 2015
Journal of Environmental Planning and Management 58 (2015)10. - ISSN 0964-0568 - p. 1853 - 1876.
sustainable consumption - uk households - cold homes - conservation - policy - strategies - spillover - barriers - savings - agenda
Retrofitting existing housing stock to improve energy efficiency is often required to meet climate mitigation, public health and fuel poverty targets. Increasing uptake and effectiveness of retrofit schemes requires understanding of their impacts on householder attitudes and behaviours. This paper reports results of a survey of 500 Kirklees householders in the UK, where the Kirklees Warm Zone scheme took place. This was a local government led city scale domestic retrofit programme that installed energy efficiency measures at no charge in over 50,000 houses. The results highlight key design features of the scheme, socio-economic and attitudinal factors that affected take-up of energy efficiency measures and impacts on behaviour and energy use after adoption. The results emphasise the role that positive feedback plays in reinforcing pro-environmental attitudes and behaviours of participants and in addressing concerns of non-participants. Our findings have implications for the design and operation of future domestic energy efficiency retrofit schemes.
Rescaling spatial planning: spatial planning reforms in Denmark, England, and the Netherlands
Roodbol-Mekkes, P.H. ; Brink, A. van den - \ 2015
Environment and Planning C. Government and Policy 33 (2015)1. - ISSN 0263-774X - p. 184 - 198.
local-government modernization - sustainable development - english regions - governance - space - rethinking - strategies - growth - europe - scale
Following a wave of spatial planning reforms at the beginning of the 21st century, a second wave of reforms has recently swept through several European countries. In this study we investigate the significance of these latest developments by analysing the reforms in Denmark, England, and the Netherlands from the perspective of rescaling, the process of redividing tasks, and responsibilities between the various tiers of government. We show that the reasoning behind the new planning systems and the philosophy they were based on were remarkably similar. Typical catchphrases, such as ‘closer to the citizen’ and ‘development-oriented spatial planning’, were used in each of the countries under study. Although the second wave of changes is legitimised by much of the same wording, the changes are significantly different because comprehensive visions on the integrated spatial development at the national and regional level have been almost completely abandoned. The loss of this ‘something more’ seems to impact the core of spatial planning.
National prevalence and associated risk factors of hypertension and prehypertension among Vietnamese adults
Ha, Do T.P. ; Geleijnse, J.M. ; Le, M.B. ; Kok, F.J. ; Feskens, E.J.M. - \ 2015
American Journal of Hypertension 28 (2015)1. - ISSN 0895-7061 - p. 89 - 97.
blood-pressure - double burden - population - awareness - health - prevention - nutrition - countries - consumption - strategies
BACKGROUND Hypertension has recently been identified as the leading risk factor for global mortality. This study aims to present the national prevalence of hypertension and prehypertension and, their determinants in Vietnamese adults. METHODS Nationally representative data were obtained from the National Adult Overweight Survey 2005. This one visit survey included 17,199 subjects aged 25–64 years, with a mean body mass index (BMI) of 20.7kg/m2. RESULTS The overall census-weighted JNC7 (the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure) defined prevalence of hypertension was 20.7% (95% confidence interval (CI) = 19.4–22.1); the prevalence of prehypertension was 41.8% (95% CI = 40.4–43.1). Hypertension and prehypertension were more prevalent in men. Higher age, overweight, alcohol use (among men), and living in rural areas (among women) were independently associated with a higher prevalence of hypertension, whereas higher physical activity and education level were inversely associated. Age, BMI, and living in rural areas were independently associated with an increased prevalence of prehypertension. Among the hypertensives, 25.9% were aware of their hypertension, 12.2% were being treated, and 2.8% had their blood pressure under control; among the treated hypertensives, 32.4% had their blood pressure controlled.
Estimating enteric methane emissions from Chilean beef fattening systems using a mechanistic model
Arias, R.A. ; Catrileo, A. ; Larraín, R. ; Vera, R. ; Velásquez, A. ; Toneatti, M. ; France, J. ; Dijkstra, J. ; Kebreab, E. - \ 2015
The Journal of Agricultural Science 153 (2015)1. - ISSN 0021-8596 - p. 114 - 123.
dairy-cows - feedlot cattle - rumen - supplementation - fermentation - performance - management - monensin - strategies - prediction
A mechanistic model (COWPOLL) was used to estimate enteric methane (CH4) emissions from beef production systems in Chile. The results expressed as a proportion of gross energy intake (GEI) were compared with enteric fermentation data reported in the last Chilean greenhouse gases inventory, which utilized an earlier the Intergovernmental Panel on Climate Change Tier 2 approach. The simulation analysis was based on information from feedstuffs, dry matter intake (DMI), body weight (BW) and average daily gain (ADG) of steers raised and finished at two research facilities located in Central and Southern Chile, as well as three simulated scenarios for grass-based finishing systems in Southern Chile. Data for feedlot production systems in the central region were assessed by considering steers fed a forage : concentrate ratio of 23 : 77 using maize silage and wheat straw as roughage sources during the stages of backgrounding and fattening. Average DMI were 7·3±0·62 and 9·2±0·55 kg/day per steer for backgrounding and fattening, respectively, whereas ADG were 1·1±0·22 and 1·3±0·37 kg/day for backgrounding and fattening. For the Southern Chilean fattening production systems, the forage : concentrate ratio was 56 : 44 with ryegrass pasture as the sole forage source. In this case, average DMI was 9·97±0·51 and ADG was 1·1±0·24 kg/day per steer. Two of the grass-based scenarios used the same initial BW information as that used for the Central and Southern Chilean systems, but feedlot diets were replaced by ryegrass pasture. The third grass-based scenario used an initial BW of 390 kg. In all the grass-based scenarios an ADG of 0·90 kg/day, with maximum DMI estimated as a proportion of BW (0·01 of NDF, kg/kg BW), was assumed. The results of the simulation analysis showed that emission factors (Ym; fraction of GEI) ranged from 0·062 to 0·079 of GEI. Smaller values were associated with finishing systems that included a lower proportion of forage in the diet due to higher propionate production, which serves as a sink for hydrogen in the rumen. Cattle finished in feedlot systems had an average of 0·062 of GEI lost as CH4, whereas grass-based cattle had losses of 0·079 of GEI. Enteric CH4 emissions for the systems using grass-based and concentrate diets were 261 and 159 g/kg weight gain, respectively. The Chilean CH4 inventory employs a fixed Ym of 0·060 to estimate enteric fermentation for all cattle. This value is lower than the average Ym obtained in the current simulation analysis (0·071 of GEI), which results in underestimation of enteric CH4 emissions from beef cattle. However, these results need to be checked against field measurements of CH4 emissions. Implementation of mechanistic models in the preparation of national greenhouse gas inventories is feasible if appropriate information is provided, allowing dietary characteristics and regional particularities to be taken into consideration.
Spatial Sampling Design for Estimating Regional GPP With Spatial Heterogeneities
Wang, J.H. ; Ge, Y. ; Heuvelink, G.B.M. ; Zhou, C.H. - \ 2014
IEEE Geoscience and Remote Sensing Letters 11 (2014)2. - ISSN 1545-598X - p. 539 - 543.
optimization - geostatistics - strategies - maize
The estimation of regional gross primary production (GPP) is a crucial issue in carbon cycle studies. One commonly used way to estimate the characteristics of GPP is to infer the total amount of GPP by collecting field samples. In this process, the spatial sampling design will affect the error variance of GPP estimation. This letter uses geostatistical model-based sampling to optimize the sampling locations in a spatial heterogeneous area. The approach is illustrated with a real-world application of designing a sampling strategy for estimating the regional GPP in the Babao river basin, China. By considering the heterogeneities in the spatial distribution of the GPP, the sampling locations were optimized by minimizing the spatially averaged interpolation error variance. To accelerate the optimization process, a spatial simulated annealing search algorithm was employed. Compared with a sampling design without considering stratification and anisotropies, the proposed sampling method reduced the error variance of regional GPP estimation.
Genetic and antigenetic charactersation of serotype a FMD viruses from East Africa to select new vaccine strains.
Bari, F.D. ; Parida, S. ; Tekleghiorghis, T. ; Dekker, A. ; Sangula, A. ; Reeve, R. ; Haydon, D.T. ; Paton, D.J. - \ 2014
Vaccine 32 (2014)44. - ISSN 0264-410X - p. 5794 - 5800.
mouth-disease virus - middle-east - foot - sites - identification - conservation - strategies - protection - evolution - spread
Vaccine strain selection for emerging foot-and-mouth disease virus (FMDV) outbreaks in enzootic countries can be addressed through antigenic and genetic characterisation of recently circulating viruses. A total of 56 serotype A FMDVs isolated between 1998 and 2012, from Central, East and North African countries were characterised antigenically by virus neutralisation test using antisera to three existing and four candidate vaccine strains and, genetically by characterising the full capsid sequence data. A Bayesian analysis of the capsid sequence data revealed the viruses to be of either African or Asian topotypes with subdivision of the African topotype viruses into four genotypes (Genotypes I, II, IV and VII). The existing vaccine strains were found to be least cross-reactive (good matches observed for only 5.4–46.4% of the sampled viruses). Three bovine antisera, raised against A-EA-2007, A-EA-1981 and A-EA-1984 viruses, exhibited broad cross-neutralisation, towards more than 85% of the circulating viruses. Of the three vaccines, A-EA-2007 was the best showing more than 90% in-vitro cross-protection, as well as being the most recent amongst the vaccine strains used in this study. It therefore appears antigenically suitable as a vaccine strain to be used in the region in FMD control programmes.
Mud, muddle and models in the knowledge value-chain to action on tropical peatland conservation
Noordwijk, M. van; Matthews, R.B. ; Agus, F. ; Farmer, J. ; Verchot, L. ; Hergoualc’h, K. ; Persch, S. ; Tata, H.L. ; Lusiana, B. ; Widayati, A. ; Dewi, S. - \ 2014
Mitigation and Adaptation Strategies for Global Change 19 (2014)6. - ISSN 1381-2386 - p. 887 - 905.
greenhouse-gas emissions - hydrological restoration - central kalimantan - carbon-dioxide - climate-change - decomposition - strategies - management - indonesia - soils
Tropical peatlands are known not only for their high, area-based, carbon emissions in response to land-use change but also as hot spots of debate about associated data uncertainties. Perspectives are still evolving on factors underlying the variability and uncertainty. Debate includes the ways of reducing emissions through rewetting, reforestation and agroforestry. A knowledge value-chain that is long and complex links (a) fundamental understanding of peat and peatland processes leading to sciencebased quantification and default values, (b) willingness and (c) ability to act towards emission reduction, and ultimately (d) to local, national and global actions that effectively provide rules, incentives and motivation to conserve peat and reduce emissions. We discuss this value chain, its stakeholders and issues that still remain partially unresolved.We conclude that, to shorten the denial and conspiracy-theory stages of debate that otherwise slow down steps B and C, networks of international and national scientists have to be involved at the early stage of identifying policysensitive environmental issues. Models span part of the knowledge value-chain but transition of analysis units requires specific attention, from soil volumes through area and commodity flows to opportunities for reductions. While drainage of peatlands triggers landscape-scale increases in emissions, factors beyond drainage depth, including nutrient supply, may have a major influence on decomposition rates. Attempts to disentangle the contributions of plant and peat-based respiration in surface flux measurements involve assumptions that cannot be easily verified in comparisons between land uses. With progress on A leading to new internationally accepted defaults and with resistance on step B reduced, the reality of C and lack of working solutions for D is currently constraining further progress.
Ecosystem Services and Opportunity Costs Shift Spatial Priorities for Conserving Forest Biodiversity
Schroter, M. ; Rusch, G.M. ; Barton, D.N. ; Blumentrath, S. ; Nordén, B. - \ 2014
PLoS One 9 (2014)11. - ISSN 1932-6203 - 12 p.
protected areas - trade-offs - rich forests - conservation - landscapes - strategies - payments - benefits - science - norway
Inclusion of spatially explicit information on ecosystem services in conservation planning is a fairly new practice. This study analyses how the incorporation of ecosystem services as conservation features can affect conservation of forest biodiversity and how different opportunity cost constraints can change spatial priorities for conservation. We created spatially explicit cost-effective conservation scenarios for 59 forest biodiversity features and five ecosystem services in the county of Telemark (Norway) with the help of the heuristic optimisation planning software, Marxan with Zones. We combined a mix of conservation instruments where forestry is either completely (non-use zone) or partially restricted (partial use zone). Opportunity costs were measured in terms of foregone timber harvest, an important provisioning service in Telemark. Including a number of ecosystem services shifted priority conservation sites compared to a case where only biodiversity was considered, and increased the area of both the partial (+36.2%) and the non-use zone (+3.2%). Furthermore, opportunity costs increased (+6.6%), which suggests that ecosystem services may not be a side-benefit of biodiversity conservation in this area. Opportunity cost levels were systematically changed to analyse their effect on spatial conservation priorities. Conservation of biodiversity and ecosystem services trades off against timber harvest. Currently designated nature reserves and landscape protection areas achieve a very low proportion (9.1%) of the conservation targets we set in our scenario, which illustrates the high importance given to timber production at present. A trade-off curve indicated that large marginal increases in conservation target achievement are possible when the budget for conservation is increased. Forty percent of the maximum hypothetical opportunity costs would yield an average conservation target achievement of 79%.
Perceptions on healthy eating, physical activity and lifestyle advice: opportunities for adapting lifestyle interventions to individuals with low socioeconomic status
Bukman, A.J. ; Teuscher, D. ; Feskens, E.J.M. ; Baak, M.A. van; Meershoek, A. ; Renes, R.J. - \ 2014
BMC Public Health 14 (2014). - ISSN 1471-2458 - 22 p.
deprived neighborhoods - diabetes prevention - european countries - leisure-time - women - inequalities - food - strategies - behaviors - weight
Background Individuals with low socioeconomic status (SES) are generally less well reached through lifestyle interventions than individuals with higher SES. The aim of this study was to identify opportunities for adapting lifestyle interventions in such a way that they are more appealing for individuals with low SES. To this end, the study provides insight into perspectives of groups with different socioeconomic positions regarding their current eating and physical activity behaviour; triggers for lifestyle change; and ways to support lifestyle change. Methods Data were gathered in semi-structured focus group interviews among low SES (four groups) and high SES (five groups) adults. The group size varied between four and nine participants. The main themes discussed were perceptions and experiences of healthy eating, physical activity and lifestyle advice. Interviews were transcribed verbatim and a thematic approach was used to analyse the data. Results In general, three key topics were identified, namely: current lifestyle is logical for participants given their personal situation; lifestyle change is prompted by feedback from their body; and support for lifestyle change should include individually tailored advice and could profit from involving others. The perceptions of the low SES participants were generally comparable to the perceptions shared by the high SES participants. Some perceptions were, however, especially shared in the low SES groups. Low SES participants indicated that their current eating behaviour was sometimes affected by cost concerns. They seemed to be especially motivated to change their lifestyle when they experienced health complaints, but were rather hesitant to change their lifestyle for preventive purposes. Regarding support for lifestyle change, low SES participants preferred to receive advice in a group rather than on their own. For physical activities, groups should preferably consist of persons of the same age, gender or physical condition. Conclusions To motivate individuals with low SES to change their lifestyle, it may be useful to (visually) raise their awareness of their current weight or health status. Lifestyle interventions targeting individuals with low SES should take possible cost concerns into account and should harness the supportive effect of (peer) groups.
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