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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Balancing and counterbalancing : the Indonesian state addressing pressures to improve palm oil sector sustainability
Pramudya, Eusebius Pantja - \ 2018
University. Promotor(en): Katrien Termeer, co-promotor(en): Otto Hospes. - Wageningen : Wageningen University - ISBN 9789463437738 - 146
Allopolyploidization in Cucumis contributes to delayed leaf maturation with repression of redundant homoeologous genes
Yu, Xiaqing ; Wang, Xixi ; Hyldgaard, Benita ; Zhu, Zaobing ; Zhou, Rong ; Kjaer, Katrine Heinsvig ; Ouzounis, Theoharis ; Lou, Qunfeng ; Li, Ji ; Cai, Qingsheng ; Rosenqvist, Eva ; Ottosen, Carl-Otto ; Chen, Jinfeng - \ 2018
The Plant Journal 94 (2018). - ISSN 0960-7412 - p. 393 - 404.
The important role of polyploidy in plant evolution is widely recognized. However, many questions remain to be explored to address how polyploidy affects the phenotype of the plant. To shed light on the phenotypic and molecular impacts of allopolyploidy, we investigated the leaf development of a synthesized allotetraploid (Cucumis × hytivus), with an emphasis on chlorophyll development. Delayed leaf maturation was identified in C. × hytivus, based on delayed leaf expansion, initial chlorophyll deficiency in the leaves and disordered sink‐source transition. Anatomical observations also revealed disturbed chloroplast development in C. ×hytivus. The determination of chlorophyll biosynthesis intermediates suggested that the chlorophyll biosynthesis pathway of C. × hytivus is blocked at the site at which uroporphyrinogen III is catalysed to coproporphyrinogen III. Three chlorophyll biosynthesis‐related genes, HEMA1, HEME2 and POR, were significantly repressed in C. × hytivus. Sequence alignment showed both synonymous and non‐synonymous substitutions in the HEMA1, HEME2 and POR genes of the parents. Cloning of the chlorophyll biosynthetic genes suggested the retention of homoeologs. In addition, a chimeric clone of the HEMA1 gene that consisted of homologous genes from the parents was identified in C. × hytivus. Overall, our results showed that allopolyploidization in Cucumis has resulted in disturbed chloroplast development and reduced chlorophyll biosynthesis caused by the repressed expression of duplicated homologous genes, which further led to delayed leaf maturation in the allotetraploid, C. × hytivus. The preferential retention/loss of certain types of genes and non‐reciprocal homoeologous recombination were also supported in the present study, which provides new insights into the impact of allopolyploidy.
Unexpected dietary preferences of Eurasian Spoonbills in the Dutch Wadden Sea: spoonbills mainly feed on small fish not shrimp
Jouta, Jeltje ; Goeij, Petra De; Lok, Tamar ; Velilla, Estefania ; Camphuysen, Cornelis J. ; Leopold, Mardik ; Veer, Henk W. Van Der; Olff, Han ; Overdijk, Otto ; Piersma, Theunis - \ 2018
Journal of Ornithology 159 (2018)3. - ISSN 2193-7192 - p. 839 - 849.
Platalea leucorodia leucorodia - Regurgitate analysis - Restoration - Stable isotope analysis in R - Intertidal - Bayesian mixing models
After an historical absence, over the last decades Eurasian Spoonbills Platalea leucorodia leucorodia have returned to breed on the barrier islands of the Wadden Sea. The area offers an abundance of predator-free nesting habitat, low degrees of disturbance, and an extensive intertidal feeding area with increasing stocks of brown shrimp Crangon crangon, the assumed main prey of P. leucorodia leucorodia. Nevertheless, newly established and expanding colonies of spoonbills have surprisingly quickly reached plateau levels. Here we tested the often stated assertion that spoonbills mainly rely on brown shrimp as food, by quantifying the diet of chicks on the basis of regurgitates and by analysis of blood isotopes using stable isotope Bayesian mixing models. Both methods showed that, rather than brown shrimp being the staple food of spoonbill chicks,
small flatfish (especially plaice Pleuronectes platessa) and gobies (Pomatoschistus spp.) were their main prey. Unlike shrimp, small flatfish have been reported to be rather scarce in the Wadden Sea in recent years, which may explain the rapid saturation of colony size due to food-related density-dependent recruitment declines of growing colonies. By way of their diet and colony growth characteristics, spoonbills may thus indicate the availability of small fish in the Wadden Sea. We predict that the recovery to former densities of young flatfish and other juvenile/small fish in the Wadden Sea will be tracked by changing diets (more fish) and an increase in the size of Eurasian Spoonbill colonies across the Wadden Sea.
The disciplining of illegal palm oil plantations in Sumatra
Pramudya, Eusebius Pantja ; Hospes, Otto ; Termeer, C.J.A.M. - \ 2018
Third World Quarterly 39 (2018)5. - ISSN 0143-6597 - p. 920 - 940.
authoritarian environmentalism - Indonesia - Law enforcement - palm oil expansion
The Indonesian state has issued many regulations to control palm oil expansion, but they have been weakly enforced, resulting in widespread illegal plantations. During the last decade, Indonesian authorities have used force to reduce illegal plantations. This article analyses the drivers behind these actions and questions to what extent they reflect the rise of eco-authoritarianism. By investigating six cases of disciplinary action in Sumatra, we conclude that the Indonesian state is neither practising eco-authoritarianism nor constituting a green state. The disciplinary action, however, has had limited success in environmental terms due to policy incoherence, violent contestation and the sector’s historical context.
Notmaßnahmen gegen Federpicken
Niekerk, Thea van; Jong, Ingrid de; Krimpen, Marinus van; Reuvekamp, Berry ; Tuijl, Otto van; Bestman, Monique - \ 2017
Wageningen : Wageningen Livestock Research - 32
Emergency measures against feather pecking
Niekerk, Thea van; Jong, Ingrid de; Krimpen, Marinus van; Reuvekamp, Berry ; Tuijl, Otto van; Bestman, Monique - \ 2017
Wageningen : Wageningen Livestock Research - 32
A paradigm shift in sustainability governance? The emergence of sustainable landscape initiatives
Ingram, V.J. ; Hospes, Otto - \ 2017
Green logistics solutions
Aktas, Emel ; Bloemhof, J.M. ; Fransoo, Jan C. ; Günther, Hans Otto ; Jammernegg, Werner - \ 2017
Flexible Services and Manufacturing Journal (2017). - ISSN 1936-6582 - 3 p.
Omega-6 fatty acid biomarkers and incident type 2 diabetes : Pooled analysis of individual-level data for 39 740 adults from 20 prospective cohort studies
Wu, Jason H.Y. ; Marklund, Matti ; Imamura, Fumiaki ; Tintle, Nathan ; Ardisson Korat, Andres V. ; Goede, Janette de; Zhou, Xia ; Yang, Wei Sin ; Oliveira Otto, Marcia C. de; Kröger, Janine ; Qureshi, Waqas ; Virtanen, Jyrki K. ; Bassett, Julie K. ; Frazier-Wood, Alexis C. ; Lankinen, Maria ; Murphy, Rachel A. ; Rajaobelina, Kalina ; Gobbo, Liana C. Del; Forouhi, Nita G. ; Luben, Robert ; Khaw, Kay Tee ; Wareham, Nick ; Kalsbeek, Anya ; Veenstra, Jenna ; Luo, Juhua ; Hu, Frank B. ; Lin, Hung Ju ; Siscovick, David S. ; Boeing, Heiner ; Chen, Tzu An ; Steffen, Brian ; Steffen, Lyn M. ; Hodge, Allison ; Eriksdottir, Gudny ; Smith, Albert V. ; Gudnason, Vilmunder ; Harris, Tamara B. ; Brouwer, Ingeborg A. ; Berr, Claudine ; Helmer, Catherine ; Samieri, Cecilia ; Laakso, Markku ; Tsai, Michael Y. ; Giles, Graham G. ; Nurmi, Tarja ; Wagenknecht, Lynne ; Schulze, Matthias B. ; Lemaitre, Rozenn N. ; Chien, Kuo Liong ; Soedamah-Muthu, Sabita S. ; Geleijnse, Johanna M. ; Sun, Qi ; Harris, William S. ; Lind, Lars ; Ärnlöv, Johan ; Riserus, Ulf ; Micha, Renata ; Mozaffarian, Dariush - \ 2017
The Lancet Diabetes & Endocrinology 5 (2017)12. - ISSN 2213-8587 - p. 965 - 974.
Background: The metabolic effects of omega-6 polyunsaturated fatty acids (PUFAs) remain contentious, and little evidence is available regarding their potential role in primary prevention of type 2 diabetes. We aimed to assess the associations of linoleic acid and arachidonic acid biomarkers with incident type 2 diabetes. Methods: We did a pooled analysis of new, harmonised, individual-level analyses for the biomarkers linoleic acid and its metabolite arachidonic acid and incident type 2 diabetes. We analysed data from 20 prospective cohort studies from ten countries (Iceland, the Netherlands, the USA, Taiwan, the UK, Germany, Finland, Australia, Sweden, and France), with biomarkers sampled between 1970 and 2010. Participants included in the analyses were aged 18 years or older and had data available for linoleic acid and arachidonic acid biomarkers at baseline. We excluded participants with type 2 diabetes at baseline. The main outcome was the association between omega-6 PUFA biomarkers and incident type 2 diabetes. We assessed the relative risk of type 2 diabetes prospectively for each cohort and lipid compartment separately using a prespecified analytic plan for exposures, covariates, effect modifiers, and analysis, and the findings were then pooled using inverse-variance weighted meta-analysis. Findings: Participants were 39 740 adults, aged (range of cohort means) 49-76 years with a BMI (range of cohort means) of 23·3-28·4 kg/m2, who did not have type 2 diabetes at baseline. During a follow-up of 366 073 person-years, we identified 4347 cases of incident type 2 diabetes. In multivariable-adjusted pooled analyses, higher proportions of linoleic acid biomarkers as percentages of total fatty acid were associated with a lower risk of type 2 diabetes overall (risk ratio [RR] per interquintile range 0·65, 95% CI 0·60-0·72, p<0·0001; I 2=53·9%, pheterogeneity=0·002). The associations between linoleic acid biomarkers and type 2 diabetes were generally similar in different lipid compartments, including phospholipids, plasma, cholesterol esters, and adipose tissue. Levels of arachidonic acid biomarker were not significantly associated with type 2 diabetes risk overall (RR per interquintile range 0·96, 95% CI 0·88-1·05; p=0·38; I 2=63·0%, pheterogeneity<0·0001). The associations between linoleic acid and arachidonic acid biomarkers and the risk of type 2 diabetes were not significantly modified by any prespecified potential sources of heterogeneity (ie, age, BMI, sex, race, aspirin use, omega-3 PUFA levels, or variants of the FADS gene; all pheterogeneity≥0·13). Interpretation: Findings suggest that linoleic acid has long-term benefits for the prevention of type 2 diabetes and that arachidonic acid is not harmful. Funding: Funders are shown in the
Differential effects of elevated air humidity on stomatal closing ability of Kalanchoë blossfeldiana between the C3 and CAM states
Fanourakis, Dimitrios ; Hyldgaard, Benita ; Gebraegziabher, Habtamu ; Bouranis, Dimitris ; Körner, Oliver ; Nielsen, Kai Lønne ; Ottosen, Carl-Otto - \ 2017
Environmental and Experimental Botany 143 (2017). - ISSN 0098-8472 - p. 115 - 124.
Air humidity - Evaporative demand - Facultative CAM species - Stomata - Stomatal conductance - Transpiration

High relative air humidity (RH ≥ 85%) impairs stomatal functionality, attenuating plant capacity to cope with abiotic stress. Previous studies were limited to C3 species, so the RH effect on stomatal physiology of CAM plants remains unexplored. We addressed the topic through comparisons of C3 and CAM states in a facultative CAM species. These states were validated by diel measurements of net assimilation rate and malate level. In the first two experiments, three Kalanchoë interspecific hybrid cultivars were exposed to moderate (60%) or high (90%) RH. Both leaves that expanded at high RH and leaves that had expanded at moderate RH and were subsequently exposed to high RH (for nine days) showed increased stomatal conductance. In the third experiment, both C3 and CAM state plants of one K. blossfeldiana cultivar were exposed to low (40%), moderate (60%) or high (90%) RH. Plant transpiration during night-time was inversely related to ambient RH in either state, whereas during day-time a significant effect was only noted at 90% RH. Kalanchoë leaves showed a very effective control of water loss upon water deprivation, especially in the CAM state. Following a single week exposure to 90% RH, detached leaves showed increased rates of water loss during desiccation in C3 state plants. No effect of high RH on stomatal response to desiccation was noted in leaves detached from plants in CAM-state. It is concluded that the negative effect of either growth or one-week exposure to high RH is restricted to the C3 state in Kalanchoë.

Seed for change : the making and implementation of seed policies in Ethiopia
Hassena Beko, Mohammed - \ 2017
University. Promotor(en): Bernd van der Meulen, co-promotor(en): Bram de Jonge; Otto Hospes; Niels Louwaars. - Wageningen : Wageningen University - ISBN 9789463436687 - 151
governance - agricultural policy - policy processes - agricultural sector - seed production - government policy - ethiopia - east africa - landbouwbeleid - beleidsprocessen - landbouwsector - zaadproductie - overheidsbeleid - ethiopië - oost-afrika

Ethiopia is an agrarian country where agriculture dominates the economy, and thus agriculture is considered as an engine of growth by the government. Seed as one of the agricultural technologies, in fact, a carrier of many technologies, is critical to increasing production, but the use of quality seed from formal sources in Ethiopia is very limited. The current Ethiopian government has focused on agricultural development and has developed different policies both for agriculture in general and for the seed sector in particular. Following the developmental state approach, the government intensified its involvement in the seed sector to enhance agricultural development. Despite the policies and efforts of the government, a shortage of seed, a mismatch between demand and supply, the carryover of seed despite not satisfying the demand of farmers, and poor seed quality have been persistent challenges to the Ethiopian seed sector. Many studies have identified technical gaps that limit the development of the seed sector, and some of the studies have also discussed the extent to which policy responds to existing problems, and the extent to which what is in the policy documents is implemented. However, the causes of these ‘gaps’ are seldom discussed. The lack of such knowledge limits the understanding of the challenges, making it difficult to properly support the seed sector. For these reasons, this research has gone beyond the mere identification of ‘gaps’, aiming to analyse how actors and institutions influence seed policy making and implementation in Ethiopia.

The goal of this research is twofold: to narrow the knowledge gap about policy making and implementation in the Ethiopian seed sector, and to contribute to the debate concerning how to make the seed sector function better. The central research question is: how did actors and institutions influence the formulation and implementation of seed policies in Ethiopia from 2008 to 2016? The empirical research to answer this overall research question addresses two processes: policy making and policy implementation. These include the process of revising the 2000 Ethiopian seed law and the process of implementing direct seed marketing. By analysing these two processes, the thesis unravels how actors and associated institutions have influenced seed policy making and implementation in Ethiopia. The major sources of data were interviews of actors in the seed sector, and desk research of different reports. Guided by theoretical concepts, the research used qualitative methods to generate and analyse data.

Given the complexity of societal phenomenon, several analytical lenses have been used to examine the data in this research. In order to explain how actors negotiate the content of a policy document, including defining the problem and solution, the concept of discourse analysis is used, focusing on frame, the rounds model, and the policy arena. Similarly, to explain the process of implementing the existing policy and the outcome, the concepts of multi-level perspective on transition, transition management, non-decision making, and institutional lock-in are used. While using these analytical lenses to explain seed policy making and implementation, the concept of institutions has remained a central concept.

Chapter 2 analyses the negotiation process, looking into the topics of seed sector governance and variety registration. The analysis reveals that different policy arenas provide opportunities for different actors to place their preferred policy options on the table, and to get them incorporated into the draft working document. While this is a positive step towards a deliberative policy making, the final decision is made by the executive branch of the government. Such a process can be explained by two informal institutions. These are the loose connection between the drafting arenas and the decision-making arenas, and the blurred separation of power between the executive and the legislature. At the Council of Ministers (CoM), where the critical decisions are made, the ministry presents its perspective, particularly on issues where disagreement exists between the ministry and other actors. The council uses the content of the draft and the justification of the ministry for endorsing the draft policy document. Moreover, the parliament can change the content of the draft policy document only if the ministry agrees with the change, regardless of the arguments and justifications provided by other stakeholders. Thus, the inputs of stakeholders are considered as long as the ministry agrees with the suggestions, and the policy decision remains in the hands of the ministry.

Chapter 3 presents the different frames used by different actors to describe the problem of seed quality. While government officials attribute the problem of seed quality to the lack of alignment between the seed sector governance and the regional government structure, experts and bureaucrats attribute the problem to the lack of coordination at national level. As a result, they respectively suggest the decentralization and centralization of seed sector governance. These frames are embedded in the overall interest and strategy of the actors promoting the frames. The centralization frame reflects the interest of experts and bureaucrats to have a say with regards to the seed sector. They have lost this power because of the federal structure that was established formally in 1995. On the contrary, the decentralization frame is embedded in the government’s aim to implement the constitution that established the federal structure in 1995. Despite the fact that the process of revising the seed law took about four years, these actors could not agree on either of the options or find an alternative. This shows a lack of deliberation and reflexivity during the process of revising the seed law, reflecting the fact that seed policy discussion has been part of a larger debate about (de)centralization in Ethiopia since 1991. Thus, in addition to the issue of seed quality, the frames of centralization and decentralization are shaped by the old (unitary) and the new (federal) institutions of the Ethiopian government system.

Chapter 4 focuses on the process of introducing and expanding direct seed marketing (DSM) in Ethiopia. Despite the fact that seed marketing is included in the policies on paper, the seed of major food crops is distributed through government channels resulting in inefficiency of seed distribution. The regional seed core groups introduced DSM in 2011, and by 2016 about one-third of the hybrid maize seed, the main seed marketed in Ethiopia, in Amhara, Oromia and the Southern Nations, Nationalities and Peoples’ region (SNNPR), was sold through DSM. The presence of actors outside the seed distribution system was instrumental for introducing the concept of DSM. To start the piloting of this existing policy, the core group needed to get approval from the heads of the bureaus of agriculture (BoAs). However, such approval was not required for other new ideas, like establishing an independent regulatory body, showing how the informal institutions guide what has to be approved by bureau heads, regardless of the formal policy. In addition to the demonstrated potential of DSM to overcome the problem of seed distribution inefficiency, strategic management of the stakeholders' process was critical in expanding the area under the pilot. Many actors, including the executives, supported the expansion of DSM to many areas.

Despite the expansion of DSM, its demonstrated potential to overcome the problem of seed supply inefficiency, the support it received from the government officials, and the general policy of market-based approach, the government has not endorsed the use of DSM beyond the pilot. Chapter 5 points out that the government excluded the issue of seed marketing from the seed regulation enacted in 2016, showing that the government has no intention to make seed marketing one of the seed delivery channels in the near future. The major reasons for this are: bureaucrats do not want to contribute to the decision making of DSM because they assume that the government has a strong political interest to remain in seed distribution; bureaucrats need the seed distribution system to achieve the targets set by the government; there is a symbiotic relationship between actors, the extension service as well as seed producers, and the seed distribution system, and so actors want to maintain the distribution system Such institutionalized thinking and practices have created an institutional lock-in that prevents bureaucrats from presenting the recommendation to government officials, thereby leading to non-decision about the future of DSM.

Chapter 6 summarizes the action of actors in affecting policy making and implementation as influenced by two conflicting sets of institutions. The first set relates to market-based thinking versus centralized planning as leading principles for economic development. Both are used as a discourse for promoting economic development and its operationalization, which are shaping how actors view and overcome the problems of the seed sector. This also explains why policies on paper are not implemented and why new initiatives are not formally endorsed. The tension between these divergent institutions has increased because of the dual use of seed by the government: the government has used the seed to both promote economic development and maintain strong political ties with farmers. The second set of conflicting institutions relates to authoritarian versus participatory decision making. On the one hand, is the government practice of authoritative decision-making, where only the input of stakeholders is considered when it fits in with the existing policy direction of the executives. On the other hand, it is common practice to organize stakeholders to contribute to policy making and implementation. The practice of considering the policy input of others only when it fits in with the policy direction of the decision-makers, creates a sense of being forced to accept, increasing the tension between how the government decides and the role of stakeholders.

Given the tension between the conflicting institutions, and circumstances in Ethiopia, this research suggested that choosing one approach over the other will not guarantee the development of the seed sector. There is no guarantee that the outcome of a deliberative policy making process will be a different policy option than the one opted for by one of the actors. However, the co-development of a solution for the shared seed sector problem will guarantee better ownership and thus better implementation than an imposed policy. It is also important to note that deliberative policy making and implementation is not an easy task given the current stakeholders’ landscape and the culture of authoritative decision making. Thus, the change towards deliberative policy making and implementation is not something that emerges overnight: it is a process that matures over time. This calls for the strategic management of a process of change that leads to the transformation of the seed sector into a self-reliant and resilient sector. By identifying the underlying institutions behind the challenges of the seed sector and suggesting options for improvement, this thesis contributes to the debate on how to make the seed sector function better. At a higher level, it also contributes to the debate on policy making and implementation processes in Ethiopia.

Application of laser-based photoacoustic spectroscopy and colorimetry for quantification of anthocyanin in hard boiled candy
Kovács, Mihály ; Dóka, Ottó ; Bicanic, Dane ; Ajtony, Zsolt - \ 2017
Microchemical Journal 135 (2017). - ISSN 0026-265X - p. 100 - 104.
Anthocyanin (E163) - Colorimetry - Hard boiled candy - Laser-based photoacoustic spectroscopy - Non-destructive analysis - Spectrophotometry
The analytical performance of the newly proposed laser-based photoacoustic spectroscopy (LPAS) and colorimetric method for quantification of anthocyanin (E163) in commercially available hard boiled candies are compared to that of the spectrophotometry (SP). Both LPAS and colorimetry are direct methods that unlike SP do not require the extraction of the analyte or some additional sample treatment. Results indicate that LPAS and colorimetry are both suitable for quickly screening content of anthocyanin in hard boiled candies. The correlation between the two methods and spectrophotometry is linear with R 2 = 0.9989 for LPAS and R 2 = 0.9570 for colorimetry.
Rutin in buckwheat grain meal determined by UV photoacoustic spectroscopy and HPLC
Dóka, Ottó ; Brunori, Andrea ; Schmidt, Rezso ; Bicanic, Dane ; Végvári, György - \ 2017
Nova Biotechnologica et Chimica 16 (2017)1. - ISSN 1338-6905 - p. 61 - 67.
Buckwheat - Grain rutin content - UV photoacoustic spectroscopy
A relatively novel approach for easy and quick determination of rutin in buckwheat grain is suggested. The rutin content of the grain in seven common buckwheat (Fagopyrum esculentum) and six Tartary buckwheat (Fagopyrum tataricum) varieties was investigated by means of UV photoacoustic spectroscopy and HPLC as reference method. The lowest content was found in 'Botan' and 'Bamby' varieties, while the highest values were obtained in the variety 'Emka'. Rutin content in grain of all Tartary buckwheat varieties was two orders of magnitude higher than in the other varieties. Rutin content in F. esculentum ranges between 9 and 36 mg/100 g dry weight as compared to 921 to 2 132 mg/100 g dry weight in F. tataricum. The UV photoacoustic spectroscopy data show rather good correlations of R2=0.977 and R2=0.980 with values obtained by HPLC data for all measured samples. Therefore, UV photoacoustic spectroscopy can be a cheap and quick method for determining rutin content in buckwheat grain.
The (Re-)Positioning of the Indonesian and Malaysian State in Sustainable Palm Oil Governance
Hospes, Otto - \ 2017
When CSR meets plural legal order: can palm oil companies do better than public authorities by committing to zero-deforestation in Indonesia?
Hospes, Otto - \ 2017
Enhanced methane emissions from tropical wetlands during the 2011 la Niña
Pandey, Sudhanshu ; Houweling, Sander ; Krol, Maarten ; Aben, Ilse ; Monteil, Guillaume ; Nechita-Banda, Narcisa ; Dlugokencky, Edward J. ; Detmers, Rob ; Hasekamp, Otto ; Xu, Xiyan ; Riley, William J. ; Poulter, Benjamin ; Zhang, Zhen ; McDonald, Kyle C. ; White, James W.C. ; Bousquet, Philippe ; Röckmann, Thomas - \ 2017
Scientific Reports 7 (2017). - ISSN 2045-2322
Year-to-year variations in the atmospheric methane (CH4) growth rate show significant correlation with climatic drivers. The second half of 2010 and the first half of 2011 experienced the strongest La Niña since the early 1980s, when global surface networks started monitoring atmospheric CH4 mole fractions. We use these surface measurements, retrievals of column-averaged CH4 mole fractions from GOSAT, new wetland inundation estimates, and atmospheric δ13C-CH4 measurements to estimate the impact of this strong La Niña on the global atmospheric CH4 budget. By performing atmospheric inversions, we find evidence of an increase in tropical CH4 emissions of ∼6-9 TgCH4 yr-1 during this event. Stable isotope data suggest that biogenic sources are the cause of this emission increase. We find a simultaneous expansion of wetland area, driven by the excess precipitation over the Tropical continents during the La Niña. Two process-based wetland models predict increases in wetland area consistent with observationally-constrained values, but substantially smaller per-area CH4 emissions, highlighting the need for improvements in such models. Overall, tropical wetland emissions during the strong La Niña were at least by 5% larger than the long-term mean.
Liberation Deliverable 3.2: Report on the effectiveness of a range of landscape management practices
Gils, S.H. van; Marini, L. ; Ádám, Réka ; Baldi, A. ; Bereczki, Krisztina ; Dainese, Matteo ; Coston, Duncan J. ; Boros, Gergely ; Dimmers, W.J. ; Elek, Zoltan ; Garratt, Mike P.D. ; Groot, G.A. de; Kats, R.J.M. van; Kovács-Hostyánszki, Anikó ; Lammertsma, D.R. ; Montecchiari, Silvia ; Mortimer, Simon ; Potts, S.G. ; senapathi, Deepa ; Sigura, Maurizia ; Somay, László ; Szalkovszki, Ottó ; Sitzia, Tommaso ; Kleijn, D. - \ 2016
FP7 Project Liberation
Ecological intensification aims to enhance important ecosystem processes that contribute to the delivery of the ecosystem services that underpin agricultural production allowing us to reduce our reliance on synthetic inputs. The potential of ecological intensification will depend on many factors, among the most important of which are off-field management and landscape context. These factors, and importantly the interaction between them, are likely to vary across regions and countries.
Identifying off-field management approaches that are successful in enhancing ecosystem services will require assessing a range of strategies. The empirical work carried out in task 3.2 provided Original data on the effectiveness of three off-field interventions (hedgerow, set- aside and flower strips) on
the delivery of biocontrol and yield in winter cereals across different European countries. For hedgerows we found that the quality of the hedgerow (flower diversity) generally increased biodiversity of several beneficial groups of insects (e.g. butterflies, tachinids, carabids, spiders), while the delivery of ecosystems services such as pollination and pest control tended to respond more to
landscape factors (proportion of hedgerows or semi-natural habitats in general in the surrounding).
For set-aside we found that this intervention increased locally the biodiversity of several beneficial insect groups (literature) but the spillover to winter wheat fields was small with no apparent benefit on the delivery of aphid biocontrol. Finally, we found that wildflower strips helped to reduce aphid pests in winter wheat fields, which, in turn, enhanced crop yield. However, this potential may only be reached in case strips are properly managed, in a way that optimizes floral diversity, and may only be relevant in agricultural landscapes with a low availability of habitat area for natural enemies.
Irrespective of the intensity of the agricultural systems, the two most promising interventions to foster biocontrol and support yield in winter wheats are hedgerows and flower strips, but their effect appeared to be stronger in landscapes with low cover of existing semi-natural habitats.
How do NGOs define, safeguard and stimulate inclusiveness in public-private partnerships for development
Hospes, Otto - \ 2016
Improving stomatal functioning at elevated growth air humidity : A review
Fanourakis, Dimitrios ; Bouranis, Dimitrios ; Giday, Habtamu ; Alves Carvalho, Dalia ; Rezaei Nejad, Abdolhossein ; Ottosen, Carl Otto - \ 2016
Journal of Plant Physiology 207 (2016). - ISSN 0176-1617 - p. 51 - 60.
Abscisic acid - Evaporative demand - Stomatal closing ability - Stomatal size - Water loss

Plants grown at high relative air humidity (RH ≥ 85%) are prone to lethal wilting upon transfer to conditions of high evaporative demand. The reduced survival of these plants is related to (i) increased cuticular permeability, (ii) changed anatomical features (i.e., longer pore length and higher stomatal density), (iii) reduced rehydration ability, (iv) impaired water potential sensitivity to leaf dehydration and, most importantly, (v) compromised stomatal closing ability. This review presents a critical analysis of the strategies which stimulate stomatal functioning during plant development at high RH. These include (a) breeding for tolerant cultivars, (b) interventions with respect to the belowground environment (i.e., water deficit, increased salinity, nutrient culture and grafting) as well as (c) manipulation of the aerial environment [i.e., increased proportion of blue light, increased air movement, temporal temperature rise, and spraying with abscisic acid (ABA)]. Root hypoxia, mechanical disturbance, as well as spraying with compounds mimicking ABA, lessening its inactivation or stimulating its within-leaf redistribution are also expected to improve stomatal functioning of leaves expanded in humid air. Available evidence leaves little doubt that genotypic and phenotypic differences in stomatal functioning following cultivation at high RH are realized through the intermediacy of ABA.

Evaluating the performance of land surface model ORCHIDEE-CAN v1.0 on water and energy flux estimation with a single-and multi-layer energy budget scheme
Chen, Yiying ; Ryder, James ; Bastrikov, Vladislav ; McGrath, Matthew J. ; Naudts, Kim ; Otto, Juliane ; Ottlé, Catherine ; Peylin, Philippe ; Polcher, Jan ; Valade, Aude ; Black, Andrew ; Elbers, Jan A. ; Moors, Eddy ; Foken, Thomas ; Gorsel, Eva Van; Haverd, Vanessa ; Heinesch, Bernard ; Tiedemann, Frank ; Knohl, Alexander ; Launiainen, Samuli ; Loustau, Denis ; Ogeé, Jérôme ; Vessala, Timo ; Luyssaert, Sebastiaan - \ 2016
Geoscientific Model Development 9 (2016)9. - ISSN 1991-959X - p. 2951 - 2972.

Canopy structure is one of the most important vegetation characteristics for land-atmosphere interactions, as it determines the energy and scalar exchanges between the land surface and the overlying air mass. In this study we evaluated the performance of a newly developed multi-layer energy budget in the ORCHIDEE-CAN v1.0 land surface model (Organising Carbon and Hydrology In Dynamic Ecosystems-CANopy), which simulates canopy structure and can be coupled to an atmospheric model using an implicit coupling procedure. We aim to provide a set of acceptable parameter values for a range of forest types. Top-canopy and sub-canopy flux observations from eight sites were collected in order to conduct this evaluation. The sites crossed climate zones from temperate to boreal and the vegetation types included deciduous, evergreen broad-leaved and evergreen needle-leaved forest with a maximum leaf area index (LAI; all-sided) ranging from 3.5 to 7.0. The parametrization approach proposed in this study was based on three selected physical processes-namely the diffusion, advection, and turbulent mixing within the canopy. Short-term sub-canopy observations and long-term surface fluxes were used to calibrate the parameters in the sub-canopy radiation, turbulence, and resistance modules with an automatic tuning process. The multi-layer model was found to capture the dynamics of sub-canopy turbulence, temperature, and energy fluxes. The performance of the new multi-layer model was further compared against the existing single-layer model. Although the multi-layer model simulation results showed few or no improvements to both the nighttime energy balance and energy partitioning during winter compared with a single-layer model simulation, the increased model complexity does provide a more detailed description of the canopy micrometeorology of various forest types. The multi-layer model links to potential future environmental and ecological studies such as the assessment of in-canopy species vulnerability to climate change, the climate effects of disturbance intensities and frequencies, and the consequences of biogenic volatile organic compound (BVOC) emissions from the terrestrial ecosystem.

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