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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Poor urban neighbourhoods more vulnerable to extended effects of heat
Siderius, Christian ; Singh, Tanya - \ 2019
The need for bottom-up assessments of climate risks and adaptation in climate-sensitive regions
Conway, Declan ; Nicholls, Robert J. ; Brown, Sally ; Tebboth, Mark G.L. ; Adger, William Neil ; Ahmad, Bashir ; Biemans, Hester ; Crick, Florence ; Lutz, Arthur F. ; Campos, Ricardo Safra De; Said, Mohammed ; Singh, Chandni ; Zaroug, Modathir Abdalla Hassan ; Ludi, Eva ; New, Mark ; Wester, Philippus - \ 2019
Nature Climate Change 9 (2019)7. - ISSN 1758-678X - p. 503 - 511.

Studies of climate change at specific intervals of future warming have primarily been addressed through top-down approaches using climate projections and modelled impacts. In contrast, bottom-up approaches focus on the recent past and present vulnerability. Here, we examine climate signals at different increments of warming and consider the need to reconcile top-down and bottom-up approaches. We synthesise insights from recent studies in three climate-sensitive systems where change is a defining feature of the human-environment system. Whilst top-down and bottom-up approaches generate complementary insights into who and what is at risk, integrating their results is a much-needed step towards developing relevant information to address the needs of immediate adaptation decisions.

Two-dimensional solute transport with exponential initial concentration distribution and varying flow velocity
Thakur, C.K. ; Chaudhary, M. ; Zee, S.E.A.T.M. van der; Singh, M.K. - \ 2019
Pollution 5 (2019)4. - ISSN 2383-451X - p. 721 - 737.
The transport mechanism of contaminated groundwater has been a problematic issue for many decades, mainly due to the bad impact of the contaminants on the quality of the groundwater system. In this paper, the exact solution of two-dimensional advection-dispersion equation (ADE) is derived for a semi-infinite porous media with spatially dependent initial and uniform/flux boundary conditions. The flow velocity is considered temporally dependent in homogeneous media however, both spatially and temporally dependent is considered in heterogeneous porous media. First-order degradation term is taken into account to obtain a solution using Laplace Transformation Technique (LTT) for both the medium. The solute concentration distribution and breakthrough are depicted graphically. The effect of different transport parameters is studied through proposed analytical investigation. Advection-dispersion theory of contaminant mass transport in porous media is employed. Numerical solution is also obtained using Crank Nicholson method and compared with analytical result. Furthermore, accuracy of the result is discussed with root mean square error (RMSE) for both the medium. This study has developed a transport and prediction 2-D model that allows the early remediation and removal of possible pollutant in both the porous structures. The result may also be used as a preliminary predictive tool for groundwater resource and management.
High-density mapping of triple rust resistance in barley using DArT-seq markers
Dracatos, Peter M. ; Haghdoust, Rouja ; Singh, Ravi P. ; Huerta Espino, Julio ; Barnes, Charles W. ; Forrest, Kerrie ; Hayden, Matthew ; Niks, Rients E. ; Park, Robert F. ; Singh, Davinder - \ 2019
Frontiers in Plant Science 10 (2019). - ISSN 1664-462X
Barley - DArT-Seq markers - High-density linkage map - QTL - Rust resistance

The recent availability of an assembled and annotated genome reference sequence for the diploid crop barley (Hordeum vulgare L.) provides new opportunities to study the genetic basis of agronomically important traits such as resistance to stripe [Puccinia striiformis f. sp. hordei (Psh)], leaf [P. hordei (Ph)], and stem [P. graminis f. sp. tritici (Pgt)] rust diseases. The European barley cultivar Pompadour is known to possess high levels of resistance to leaf rust, predominantly due to adult plant resistance (APR) gene Rph20. We developed a barley recombinant inbred line (RIL) population from a cross between Pompadour and the leaf rust and stripe rust susceptible selection Biosaline-19 (B-19), and genotyped this population using DArT-Seq genotyping by sequencing (GBS) markers. In the current study, we produced a high-density linkage map comprising 8,610 (SNP and in silico) markers spanning 5957.6 cM, with the aim of mapping loci for resistance to leaf rust, stem rust, and stripe rust. The RIL population was phenotyped in the field with Psh (Mexico and Ecuador) and Ph (Australia) and in the greenhouse at the seedling stage with Australian Ph and Pgt races, and at Wageningen University with a European variant of Psh race 24 (PshWUR). For Psh, we identified a consistent field QTL on chromosome 2H across all South American field sites and years. Two complementary resistance genes were mapped to chromosomes 1H and 4H at the seedling stage in response to PshWUR, likely to be the loci rpsEm1 and rpsEm2 previously reported from the cultivar Emir from which Pompadour was bred. For leaf rust, we determined that Rph20 in addition to two minor-effect QTL on 1H and 3H were effective at the seedling stage, whilst seedling resistance to stem rust was due to QTL on chromosomes 3H and 7H conferred by Pompadour and B-19, respectively.

Patterns of outdoor exposure to heat in three South Asian cities
Jacobs, Cor ; Singh, Tanya ; Gorti, Ganesh ; Iftikhar, Usman ; Saeed, Salar ; Syed, Abu ; Abbas, Farhat ; Ahmad, Bashir ; Bhadwal, Suruchi ; Siderius, Christian - \ 2019
Science of the Total Environment 674 (2019). - ISSN 0048-9697 - p. 264 - 278.
Heat exposure - HI - South Asia - Urban heat island - UTCI - WBGT

Low socio-economic status has been widely recognized as a significant factor in enhancing a person's vulnerability to climate change including vulnerability to changes in temperature. Yet, little is known about exposure to heat within cities in developing countries, and even less about exposure within informal neighbourhoods in those countries. This paper presents an assessment of exposure to outdoor heat in the South Asian cities Delhi, Dhaka, and Faisalabad. The temporal evolution of exposure to heat is evaluated, as well as intra-urban differences, using meteorological measurements from mobile and stationary devices (April–September 2016). Exposure to heat is compared between low-income and other neighbourhoods in these cities. Results are expressed in terms of air temperature and in terms of the thermal indices Heat Index (HI), Wet Bulb Globe Temperature (WBGT) and Universal Thermal Climate Index (UTCI) at walking level. Conditions classified as dangerous to very dangerous, and likely to impede productivity, are observed almost every day of the measurement period during daytime, even when air temperature drops after the onset of the monsoon. It is recommended to cast heat warnings in terms of thermal indices instead of just temperature. Our results nuance the idea that people living in informal neighbourhoods are consistently more exposed to heat than people living in more prosperous neighbourhoods. During night-time, exposure does tend to be enhanced in densely-built informal neighbourhoods, but not if the low-income neighbourhoods are more open, or if they are embedded in green/blue areas.

Food in the Anthropocene : the EAT–Lancet Commission on healthy diets from sustainable food systems
Willett, Walter ; Rockström, Johan ; Loken, Brent ; Springmann, Marco ; Lang, Tim ; Vermeulen, Sonja ; Garnett, Tara ; Tilman, David ; DeClerck, Fabrice ; Wood, Amanda ; Jonell, Malin ; Clark, Michael ; Gordon, Line J. ; Fanzo, Jessica ; Hawkes, Corinna ; Zurayk, Rami ; Rivera, Juan A. ; Vries, Wim De; Majele Sibanda, Lindiwe ; Afshin, Ashkan ; Chaudhary, Abhishek ; Herrero, Mario ; Agustina, Rina ; Branca, Francesco ; Lartey, Anna ; Fan, Shenggen ; Crona, Beatrice ; Fox, Elizabeth ; Bignet, Victoria ; Troell, Max ; Lindahl, Therese ; Singh, Sudhvir ; Cornell, Sarah E. ; Srinath Reddy, K. ; Narain, Sunita ; Nishtar, Sania ; Murray, Christopher J.L. - \ 2019
The Lancet 393 (2019)10170. - ISSN 0140-6736 - p. 447 - 492.
1. Unhealthy and unsustainably produced food poses a global risk to people and the planet. More than 820 million people have insufficient food and many more consume an unhealthy diet that contributes to premature death and morbidity. Moreover, global food production is the largest pressure caused by humans on Earth, threatening local ecosystems and the stability of the Earth system. 2. Current dietary trends, combined with projected population growth to about 10 billion by 2050, will exacerbate risks to people and planet. The global burden of non-communicable diseases is predicted to worsen and the effects of food production on greenhouse-gas emissions, nitrogen and phosphorus pollution, biodiversity loss, and water and land use will reduce the stability of the Earth system. 3. Transformation to healthy diets from sustainable food systems is necessary to achieve the UN Sustainable Development Goals and the Paris Agreement, and scientific targets for healthy diets and sustainable food production are needed to guide a Great Food Transformation. 4. Healthy diets have an appropriate caloric intake and consist of a diversity of plant-based foods, low amounts of animal source foods, unsaturated rather than saturated fats, and small amounts of refined grains, highly processed foods, and added sugars. 5. Transformation to healthy diets by 2050 will require substantial dietary shifts, including a greater than 50% reduction in global consumption of unhealthy foods, such as red meat and sugar, and a greater than 100% increase in consumption of healthy foods, such as nuts, fruits, vegetables, and legumes. However, the changes needed differ greatly by region. 6. Dietary changes from current diets to healthy diets are likely to substantially benefit human health, averting about 10·8–11·6 million deaths per year, a reduction of 19·0–23·6%. 7. With food production causing major global environmental risks, sustainable food production needs to operate within the safe operating space for food systems at all scales on Earth. Therefore, sustainable food production for about 10 billion people should use no additional land, safeguard existing biodiversity, reduce consumptive water use and manage water responsibly, substantially reduce nitrogen and phosphorus pollution, produce zero carbon dioxide emissions, and cause no further increase in methane and nitrous oxide emissions. 8. Transformation to sustainable food production by 2050 will require at least a 75% reduction of yield gaps, global redistribution of nitrogen and phosphorus fertiliser use, recycling of phosphorus, radical improvements in efficiency of fertiliser and water use, rapid implementation of agricultural mitigation options to reduce greenhouse-gas emissions, adoption of land management practices that shift agriculture from a carbon source to sink, and a fundamental shift in production priorities. 9. The scientific targets for healthy diets from sustainable food systems are intertwined with all UN Sustainable Development Goals. For example, achieving these targets will depend on providing high-quality primary health care that integrates family planning and education on healthy diets. These targets and the Sustainable Development Goals on freshwater, climate, land, oceans, and biodiversity will be achieved through strong commitment to global partnerships and actions. 10. Achieving healthy diets from sustainable food systems for everyone will require substantial shifts towards healthy dietary patterns, large reductions in food losses and waste, and major improvements in food production practices. This universal goal for all humans is within reach but will require adoption of scientific targets by all sectors to stimulate a range of actions from individuals and organisations working in all sectors and at all scales.
The Effect of Psyllium Husk on Intestinal Microbiota in Constipated Patients and Healthy Controls
Jalanka, Jonna ; Major, Giles ; Murray, Kathryn ; Singh, Gulzar ; Nowak, Adam ; Kurtz, Caroline ; Silos-Santiago, Inmaculada ; Johnston, Jeffrey M. ; Vos, Willem M. de; Spiller, Robin - \ 2019
International Journal of Molecular Sciences 20 (2019)2. - ISSN 1661-6596
constipation - ispaghula - microbiome - prebiotics - transit

Psyllium is a widely used treatment for constipation. It traps water in the intestine increasing stool water, easing defaecation and altering the colonic environment. We aimed to assess the impact of psyllium on faecal microbiota, whose key role in gut physiology is being increasingly recognised. We performed two randomised, placebo-controlled, double-blinded trials comparing 7 days of psyllium with a placebo (maltodextrin) in 8 healthy volunteers and 16 constipated patients respectively. We measured the patients' gastrointestnal (GI) transit, faecal water content, short-chain fatty acid (SCFA) and the stool microbiota composition. While psyllium supplement had a small but significant effect on the microbial composition of healthy adults (increasing Veillonella and decreasing Subdoligranulum), in constipated subjects there were greater effects on the microbial composition (increased Lachnospira, Faecalibacterium, Phascolarctobacterium, Veillonella and Sutterella and decreased uncultured Coriobacteria and Christensenella) and alterations in the levels of acetate and propionate. We found several taxa to be associated with altered GI transit, SCFAs and faecal water content in these patients. Significant increases in three genera known to produce butyrate, Lachnospira, Roseburia and Faecalibacterium, correlated with increased faecal water. In summary, psyllium supplementation increased stool water and this was associated with significant changes in microbiota, most marked in constipated patients.

Timeline on the application of intercalation materials in Capacitive Deionization
Singh, K. ; Porada, S. ; Gier, H.D. de; Biesheuvel, P.M. ; Smet, L.C.P.M. de - \ 2019
Desalination 455 (2019). - ISSN 0011-9164 - p. 115 - 134.

Capacitive deionization is a water desalination technology in which ions are stored in electrodes in an electrochemical cell construction, connected to an external circuit, to remove ions present in water from various sources. Conventionally, carbon has been the choice of material for the electrodes due to its low cost, low contact resistance and high specific surface area, electronic conductivity, and ion mobility within pores. The ions in the water are stored at the pore walls of these electrodes in an electrical double layer. However, alternative electrode materials, with a different mechanism for ion and charge storage, referred to as ion intercalation, have been fabricated and studied as well. The salt adsorption performance exhibited by these materials is in most cases higher than that of carbon electrodes. This work traces the evolution of the study of redox activity in these intercalation materials and provides a chronological description of major developments in the field of Capacitive Deionization (CDI) with intercalation electrodes. In addition, some insights into the cell architecture and operation parameters are provided and we present our outlook of future developments in the field of intercalation materials for CDI.

A research roadmap for quantifying non-state and subnational climate mitigation action
Hsu, Angel ; Höhne, Niklas ; Kuramochi, Takeshi ; Roelfsema, Mark ; Weinfurter, Amy ; Xie, Yihao ; Lütkehermöller, Katharina ; Chan, Sander ; Corfee-Morlot, Jan ; Drost, Philip ; Faria, Pedro ; Gardiner, Ann ; Gordon, David J. ; Hale, Thomas ; Hultman, Nathan E. ; Moorhead, John ; Reuvers, Shirin ; Setzer, Joana ; Singh, Neelam ; Weber, Christopher ; Widerberg, Oscar - \ 2019
Nature Climate Change 9 (2019)1. - ISSN 1758-678X - p. 11 - 17.

Non-state and subnational climate actors have become central to global climate change governance. Quantitatively assessing climate mitigation undertaken by these entities is critical to understand the credibility of this trend. In this Perspective, we make recommendations regarding five main areas of research and methodological development related to evaluating non-state and subnational climate actions: defining clear boundaries and terminology; use of common methodologies to aggregate and assess non-state and subnational contributions; systematically dealing with issues of overlap; estimating the likelihood of implementation; and addressing data gaps.

Evaluation of watershed health using Fuzzy-ANP approach considering geo-environmental and topo-hydrological criteria
Alilou, Hossein ; Rahmati, Omid ; Singh, Vijay P. ; Choubin, Bahram ; Pradhan, Biswajeet ; Keesstra, Saskia ; Ghiasi, Seid Saeid ; Sadeghi, Seyed Hamidreza - \ 2019
Journal of Environmental Management 232 (2019). - ISSN 0301-4797 - p. 22 - 36.
Analytical network process - Fuzzy theory - Multi-criteria decision analysis (MCDA) - Soil erosion - Watershed health

Assessment of watershed health and prioritization of sub-watersheds are needed to allocate natural resources and efficiently manage watersheds. Characterization of health and spatial prioritization of sub-watersheds in data scarce regions helps better comprehend real watershed conditions and design and implement management strategies. Previous studies on the assessment of health and prioritization of sub-watersheds in ungauged regions have not considered environmental factors and their inter-relationship. In this regard, fuzzy logic theory can be employed to improve the assessment of watershed health. The present study considered a combination of climate vulnerability (Climate Water Balance), relative erosion rate of surficial rocks, slope weighted K-factor, topographic indices, thirteen morphometric characteristics (linear, areal, and relief aspects), and potential non-point source pollution to assess watershed health, using a new framework which considers the complex linkage between human activities and natural resources. The new framework, focusing on watershed health score (WHS), was employed for the spatial prioritization of 31 sub-watersheds in the Khoy watershed, West Azerbaijan Province, Iran. In this framework, an analytical network process (ANP) and fuzzy theory were used to investigate the inter-relationships between the above mentioned geo-environmental factors and to classify and rank the health of each sub-watershed in four classes. Results demonstrated that only one sub-watershed (C15) fell into the class that was defined as ‘a potentially critical zone’. This article provides a new framework and practical recommendations for watershed management agencies with a high level of assurance when there is a lack of reliable hydrometric gauge data.

JPI Climate - SINCERE Promotional video
Jong, F. de; Singh, T. ; Manderscheid, P. - \ 2018
Linked Data Platform for Plant Breeding and Genomics
Kuzniar, A. ; Singh, G. ; Martinez-Ortiz, C. ; Visser, R.G.F. ; Finkers, H.J. - \ 2018
- 1 p.
“Embodied Deforestation” as a New EU Policy Debate to Tackle Tropical Forest Loss: Assessing Implications for REDD+ Performance
Weatherley-Singh, Janice ; Gupta, A. - \ 2018
Forests 9 (2018)12. - ISSN 1999-4907 - 23 p.
REDD+ - European Union - forest policy - deforestation drivers - tropical forests
The need to tackle international drivers of deforestation has long been acknowledged; but remains little addressed via policy measures. In the European Union (EU), a new policy debate is emerging around the concept of “embodied deforestation”, which targets EU Agricultural commodity imports as drivers of deforestation. The notion views deforestation as an externality generated by EU imports associated with tropical deforestation. Our article examines whether this
concept represents a shift in tackling international-level drivers of tropical deforestation within EU policy. We also examine, from a networked governance perspective, whether this new debate fuels further fragmentation or rather a move towards a more integrated approach to combating tropical forest loss within EU policy, and what the implications are for other initiatives, such as the climate change related “reducing emissions from deforestation and forest degradation” (REDD+). Our analysis draws on an extensive analysis of EU policy documents and semi-structured interviews with stakeholders and EU decision-makers. We find that, despite growing debate around the concept of embodied deforestation, policy measures necessary to reduce the impact of EU consumption of agricultural commodities associated with tropical deforestation have not yet been developed. We conclude that “embodied deforestation” remains more an idea than reality within EU policy to date, with the burden of responsibility for addressing international deforestation drivers still largely remaining on developing countries. There is still potential, however, for this
debate to lead to a more integrated approach to tackling tropical deforestation within EU policy, if it comes to be seen, together with REDD+, as one of a number of linked approaches to EU efforts to combat deforestation.
Putative regulatory candidate genes for QTL linked to fruit traits in oil palm (Elaeis guineensis Jacq.)
Ting, Ngoot Chin ; Mayes, Sean ; Massawe, Festo ; Sambanthamurthi, Ravigadevi ; Jansen, Johannes ; Syed Alwee, Sharifah Shahrul Rabiah ; Seng, Tzer Ying ; Ithnin, Maizura ; Singh, Rajinder - \ 2018
Euphytica 214 (2018)11. - ISSN 0014-2336
Deli dura - Marker-assisted selection - Pseudo-chromosome - Yangambi pisifera - Yield components

Palm oil is among the most important vegetable oils, contributing to a quarter of the world’s oils and fats market. The oil palm (Elaeis guineensis Jacq.) fruitlets, which are the source of palm oil, vary from 8 to 20 g in weight. Palm oil content in the fruitlets is approximately 45–50% by weight and an increase in the percentage of mesocarp-to-fruit is likely to have a positive effect on oil yield. In this study, we report a quantitative trait loci (QTL) associated with two yield related components, namely fruit and mesocarp content in a commercial breeding population (Deli dura × Yangambi pisifera). The QTL confidence interval of about 12 cM (~ 6.7 Mbp) was fine-mapped with 31 markers (17 SNPs and 14 SSRs) consisting of 20 nuclear markers derived from the maternal parent, six paternal and five co-segregating markers. Interestingly, inheritance of the paternal alleles leads to a larger difference in both fruit and mesocarp weight, when comparing genotypes in the progeny palms. Candidate genes and transcription factors were mined from the QTL region by positioning markers on the oil palm EG5 genome build. Putative genes and transcription factors involved in various biological processes including flower organ development, flowering, photosynthesis, microtubule formation, nitrogen and lipid metabolism were identified within this QTL interval on pseudo-chromosome 3. This genome-based approach allowed us to identify a number of potential candidate gene markers associated with oil palm fruit and mesocarp weight which can be further evaluated for potential use in marker-assisted breeding.

Climates of urbanization : local experiences of water security, conflict and cooperation in peri-urban South-Asia
Roth, Dik ; Khan, Muhammad Shah Alam ; Jahan, Israt ; Rahman, Rezaur ; Narain, Vishal ; Singh, Aditya Kumar ; Priya, Monica ; Sen, Sucharita ; Shrestha, Anushiya ; Yakami, Saroj - \ 2018
Climate Policy (2018). - ISSN 1469-3062 - 16 p.
(community) resilience - Bangladesh - climate change policies - India - Nepal - peri-urban water security

This article explores changing water (in)securities in a context of urbanization and climate change in the peri-urban spaces of four South-Asian cities: Khulna (Bangladesh), Gurugram and Hyderabad (India), and Kathmandu (Nepal). As awareness of water challenges like intensifying use, deteriorating quality and climate change is growing, water security gets more scientific and policy attention. However, in peri-urban areas, the dynamic zones between the urban and the rural, it remains under-researched, despite the specific characteristics of these spaces: intensifying flows of goods, resources, people, and technologies; diversifying uses of, and growing pressures on land and water; and complex and often contradictory governance and jurisdictional institutions. This article analyses local experiences of water (in-)security, conflict and cooperation in relation to existing policies. It uses insights from the analysis of the case studies as a point of departure for a critical reflection on whether a ‘community resilience’ discourse contributes to better understanding these cases of water insecurity and conflict, and to better policy solutions. The authors argue that a community resilience focus risks neglecting important insights about how peri-urban water insecurity problems are experienced by peri-urban populations and produced or reproduced in specific socio-economic, political and policy contexts. Unless supported by in-depth hydro-social research, such a focus may depoliticize basically political questions of water (re) allocation, prioritization, and access for marginalized groups. Therefore, the authors plead for more critical awareness among researchers and policy-makers of the consequences of using a ‘community resilience’ discourse for making sense of peri-urban water (in-)security. Key policy insights There is an urgent need for more (critical) policy and scientific attention to peri-urban water insecurity, conflict, and climate change. Although a changing climate will likely play a role, more attention is needed to how water insecurities and vulnerabilities in South Asia are socially produced. Researchers and policy-makers should avoid using depoliticized (community) resilience approaches for basically socio-political problems.

The potential role of gut microbiota and its modulators in the management of propionic and methylmalonic acidemia
Burlina, Alberto ; Tims, Sebastian ; Spronsen, Francjan van; Sperl, Wolfgang ; Burlina, Alessandro P. ; Kuhn, Mirjam ; Knol, Jan ; Rakhshandehroo, Maryam ; Coşkun, Turgay ; Singh, Rani H. ; MacDonald, Anita - \ 2018
Expert Opinion on Orphan Drugs 6 (2018)11. - ISSN 2167-8707 - p. 683 - 692.
methylmalonic acid - microbiota - prebiotic - probiotic - Propionic acid

Introduction: Propionic and methylmalonic acidemia (PA/MMA) are rare inborn errors of metabolism characterized by accumulation of propionyl CoA and/or methylmalonyl CoA, resulting in potentially serious metabolic crises and clinical complications. The gut microbiota contributes a significant proportion of total propionate production and provides a potentially modifiable target. Empiric use of oral antibiotics to reduce propionate production is a common approach but is hampered by possible drug resistance, perturbation of normal gut microbiota, and toxicity. Moreover, constipation, associated with low fiber intake, inadequate fluid intake, low gut motility, and other factors, is a chronic problem in this patient population and may influence propionate production. Newer management techniques that reduce the burden of propionate and address these clinical challenges are needed. Areas covered: This paper summarizes the potential contribution of gut-related factors in PA/MMA and considers modifying gut microbiota as a management approach. Expert opinion: Dietary management of PA/MMA may be improved by specific prebiotics that modify gut microbiota to stabilize or possibly reduce PA production.

Data from: Does wolf presence reduce moose browsing intensity in young forest plantations?
Beeck Calkoen, Suzanne T.S. van; Kuijper, Dries P.J. ; Sand, Håkan ; Singh, Navinder J. ; Wieren, S.E. van; Cromsigt, Joris P.G.M. - \ 2018
behaviorally-mediated trophic cascades - anthropogenic landscapes - wolf-ungulate interactions
Large carnivores can be a key factor in shaping their ungulate prey’s behavior, which may affect lower trophic levels. While most studies on trade-offs between food acquisition and risk avoidance by ungulate prey species have been conducted in areas with limited human impact, carnivores are now increasingly returning to highly anthropogenic landscapes. Many of these landscapes are dominated by forestry, and ungulate-forestry conflicts are an increasing issue. The aim of this study was to test if the indirect effects of a re-colonizing large predator, the wolf (Canis lupus), results in a change in browsing intensity by moose (Alces alces) in young forest plantations in a boreal forest in Sweden. We selected 24 different forest plantations, with 12 located in low-wolf and 12 in high-wolf utilization areas. In each plantation, we measured browsing intensity, tree height, tree density, distance to the closest forest edge and we counted the number of moose pellet groups. In contrast to our predictions, wolf utilization was not the main driver of moose browsing patterns. Instead, moose browsing intensity declined with tree density and height. Separate analyses on the main tree species showed that wolf utilization had an influence, but browsing intensity was in fact higher in the high-wolf utilization areas for three out of five tree species. This pattern seemed to be driven by a strong confounding relationship between wolf utilization, tree density and height, which were both lower in the high-wolf utilization areas. We argue that this confounding effect is due to wolves being pushed towards the less productive parts of the landscape away from human activity centers. Therefore, we concluded that in order to better understand carnivore driven risk- mediated effects on herbivore behavior in anthropogenic landscapes we need to better understand the complexity of human-carnivore-prey-ecosystem interactions.
Intersectorality in the governance of inland fisheries
Song, Andrew M. ; Bower, Shannon D. ; Onyango, Paul ; Cooke, Steven J. ; Akintola, Shehu L. ; Baer, Jan ; Gurung, Tek B. ; Hettiarachchi, Missaka ; Islam, Mohammad Mahmudul ; Mhlanga, Wilson ; Nunan, Fiona ; Salmi, Pekka ; Singh, Vipul ; Tezzo, Xavier ; Funge-Smith, Simon J. ; Nayak, Prateep K. ; Chuenpagdee, Ratana - \ 2018
Ecology and Society 23 (2018)2. - ISSN 1708-3087
Cross-sectoral relationships - Inland fisheries - Integrative environmental governance - Valuation - Water-energy-food nexus

One of the defining characteristics of inland fisheries is that they are closely impacted by other essential human activities that rely on the same fresh or brackish water ecosystems, such as hydroelectricity generation and irrigated agriculture. Starting with the premise that an understanding of fisheries' interactions with these external sectors is in itself critical for achieving sustainability of the fisheries, this paper explores the topic of intersectoral governance and outlines an approach to analyzing the intricate and often challenging sector relationships. By drawing on examples of inland fisheries from around the world, the paper proposes four broad discursive mechanisms that can structure the study of the intersectoral dynamics, i.e., system characterization, valuation, power relations, and vertical policy interaction. A synthesis model then demonstrates their interwoven nature, revealing the way each mechanism influences one another as together they shape overall outcomes. It is apparent that analyses often need to be combined to advance more rigorous (and transdisciplinary) science and also inform appropriate courses for the governance of inland fisheries. Given the typically marginal position of fisheries in inland water-use discussions, we call for a more systematic understanding of intersectoral interactions to enhance the sector's resilience within the wider society and subsequently contribute to integrated governance of waterbodies.

Pictures or pellets? Comparing camera trapping and dung counts as methods for estimating population densities of ungulates
Pfeffer, Sabine E. ; Spitzer, Robert ; Allen, Andrew M. ; Hofmeester, Tim R. ; Ericsson, Göran ; Widemo, Fredrik ; Singh, Navinder J. ; Cromsigt, Joris P.G.M. - \ 2018
Remote Sensing in Ecology and Conservation 4 (2018)2. - ISSN 2056-3485 - p. 173 - 183.
Camera traps - pellet counts - population estimates - random encounter model - ungulates - wildlife monitoring

Across the northern hemisphere, land use changes and, possibly, warmer winters are leading to more abundant and diverse ungulate communities causing increased socioeconomic and ecological consequences. Reliable population estimates are crucial for sustainable management, but it is currently unclear which monitoring method is most suitable to track changes in multi-species assemblages. We compared dung counts and camera trapping as two non-invasive census methods to estimate population densities of moose Alces alces and roe deer Capreolus capreolus in Northern Sweden. For camera trapping, we tested the random encounter model (REM) which can estimate densities without the need to recognize individual animals. We evaluated different simplification options of the REM in terms of estimates of detection distance and angle (raw data vs. modelled) and of daily movement rate (camera trap based vs. telemetry based). In comparison to density estimates from camera traps, we found that, dung counts appeared to underestimate population density for roe deer, but not for moose. Estimates of detection distance and angle from modelled versus raw camera data resulted in nearly identical outcomes. The telemetry-derived daily movement rate for moose and roe deer resulted in much higher density estimates than the camera trap-derived estimates. We suggest that camera trapping may be a robust complement to dung counts when monitoring ungulate communities, particularly when similarities between dung pellets from sympatric deer species make unambiguous assignment difficult. Moreover, we show that a simplified use of the REM method holds great potential for large-scale citizen science-based programmes (e.g. involving hunters) that can track the rapidly changing European wildlife landscape. We suggest to include camera trapping in management programmes, where the analysis can be verified via web-based applications.

Natural variation within a species for traits underpinning C4 photosynthesis
Reeves, Gregory ; Singh, Pallavi ; Rossberg, Timo A. ; Sogbohossou, E.O.D. ; Schranz, M.E. ; Hibberd, Julian M. - \ 2018
Plant Physiology 177 (2018)2. - ISSN 0032-0889 - p. 504 - 512.

Engineering C4 photosynthesis into C3 crops could substantially increase their yield by alleviating photorespiratory losses. This objective is challenging because the C4 pathway involves complex modifications to the biochemistry, cell biology, and anatomy of leaves. Forward genetics has provided limited insight into the mechanistic basis of these properties, and there have been no reports of significant quantitative intraspecific variation of C4 attributes that would allow trait mapping. Here, we show that accessions of the C4 species Gynandropsis gynandra collected from locations across Africa and Asia exhibit natural variation in key characteristics of C4 photosynthesis. Variable traits include bundle sheath size and vein density, gas-exchange parameters, and carbon isotope discrimination associated with the C4 state. The abundance of transcripts encoding core enzymes of the C4 cycle also showed significant variation. Traits relating to water use showed more quantitative variation than those associated with carbon assimilation. We propose that variation in these traits likely adapted the hydraulic system for increased water use efficiency rather than improving carbon fixation, indicating that selection pressure may drive C4 diversity in G. gynandra by modifying water use rather than photosynthesis. The accessions analyzed can be easily crossed and produce fertile offspring. Our findings, therefore, indicate that natural variation within this C4 species is sufficiently large to allow genetic mapping of key C4 traits and regulators.

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