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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Adherence and acceptability of community-based distribution of micronutrient powders in Southern Mali
Roschnik, Natalie ; Diarra, Hawa ; Dicko, Yahia ; Diarra, Seybou ; Stanley, Isobel ; Moestue, Helen ; McClean, Judy ; Verhoef, Hans ; Clarke, Sian E. - \ 2019
Maternal and Child Nutrition 15 (2019). - ISSN 1740-8695
cluster randomised controlled trial - community-based - complementary feeding - infant and child nutrition - malaria - Mali - micronutrients - preschool children

Home fortification with micronutrient powders (MNP) has been shown to reduce anaemia, with high overall acceptability and adherence, but there is limited evidence from West Africa. Around 80% of children younger than 5 years are anaemic in Mali, and new interventions are needed. This paper reports on the adherence and acceptability of a community-led MNP intervention targeting children aged 6–59 months in Southern Mali. The MNP were delivered by a multidisciplinary group of community volunteers using community-based preschools, cooking demonstrations, and traditional communication networks to promote MNP, nutrition, hygiene, and child stimulation. The MNP were delivered alongside early childhood development interventions and seasonal malaria chemoprevention. Adherence and acceptability were evaluated through two cross-sectional surveys in 2014 and 2016 and a qualitative evaluation in 2015. Over 80% of parents reported ever having given MNP to their child, with 65% having given MNP for four or more days in the last week. Likely contributors to uptake include: perceived positive changes in the children following MNP use, the selection of a food vehicle that was already commonly given to children (morning porridge or bouillie) and the community driven, decentralized and integrated delivery approach. These findings support recommendations from recent reviews of MNP implementation to use community-based delivery approaches and behaviour change components.

A review of records of the black-capped petrel pterodroma hasitata in the caribbean sea
Leopold, Mardik F. ; Geelhoed, Steve C.V. ; Scheidat, Meike ; Cremer, Jenny ; Debrot, Adolphe O. ; Halewijn, Ruud Van - \ 2019
Marine Ornithology 47 (2019)2. - ISSN 1018-3337 - p. 235 - 241.
At-sea distribution - Black-capped Petrel - Caribbean Sea - Diablotin

The Black-capped Petrel Pterodroma hasitata is a pelagic seabird with a dangerously small population size. Remaining breeding sites are threatened by habitat loss, introduced predators, and direct harvesting. The species likely also faces several threats at sea, but because knowledge of its distribution range and ecology is meagre at best, it is challenging to take concerted action to improve its conservation status. The species is currently known to breed only on Hispaniola (in the northern Caribbean Sea), but most at-sea observations are from the Florida Current and the Gulf Stream off the southeastern coast of the USA. Within the Caribbean Sea, observations are scarce. We compiled a database of at-sea sightings of Black-capped Petrels in the Caribbean Sea from 1953 to 2018 by thoroughly reviewing published and unpublished records (Appendix 1); here, we add to the literature 12 new records from a research cruise conducted in February 2018 across the Caribbean Sea. Our database was augmented with recently published information from three birds that were fitted with tracking devices. Based on the collected information, we argue that the existing distribution maps of Black-capped Petrels need adjustments. We show that Black-capped Petrels have been recorded throughout the central parts of the Caribbean, from the known breeding sites in the north down to coastal waters off Panama, Colombia, and Venezuela. However, the birds probably forage only in small parts of the Caribbean Sea (i.e., the coastal upwelling zones off Hispaniola and Cuba in the north and off the South American mainland in the south). The waters in between (i.e., in the central Caribbean Sea) appear to be mainly used as a corridor, while the eastern and western parts are unimportant. This indicates that certain hotspots within the Caribbean Sea may be more important to this endangered species than previously thought.

Exploring the views of learners and parents on the effects of school feeding : Action research in the TIDE School Milk Programme, South West Uganda
Hove, Hermine ten; Roefs, Marlene ; Herens, Marion ; Kizito, Frederick ; Katungye, Vincent ; Mugabi, Faith ; Wasswa, Cosma ; Mugizi, Dan - \ 2019
Wageningen : Wageningen Centre for Development Innovation (Wageningen Centre for Development Innovation report 19-078) - 35
This report presents the results of the second phase of the action research on the SNV TIDE School Milk Programme (SMP). The study explores the views of learners and their parents on three aspects ofschool feeding that were identified in the first phase. These areas are 1) Relation between school and home feeding, 2) (Rise of) inequality among learners and 3) Sharing food in school. Focus group interviews were held with parents and learners in three schools, split into groups based on the level of participation in the programme.
Models of science policy: From the linear model to responsible research and innovation
Macnaghten, Philip - \ 2019
In: Wissenschaftsverantwortung: Wissenschaftsforchung Jahrbuch 2019 / Mieg, H.A., Lenk, H., Berlin : Gesellschaft für Wissenschaftsforschung - p. 111 - 131.
Naderende brexit-deadline zorgt voor veel onzekerheid bij vissers
Mol, Arie - \ 2019
The Arachnids (Arachnida) of Aruba, Bonaire and Curaçao
Crews, Sarah C. ; Debrot, A.O. ; Hoorn, Gijs van; Galvis, William ; Espodito, Lauren A. - \ 2019
Caribbean Journal of Science 49 (2019)2-3. - ISSN 0008-6452 - p. 125 - 140.
Aruba, Bonaire, and Curaçao (ABC Islands) are located at the southern margin of the Caribbean Plate, just north of South America. Little is known of the arachnid fauna of these islands, and the only work on spiders was published over a century ago. Here we provide a list of arachnids opportunistically collected from the islands, including Klein Bonaire and Klein Curaçao, over approximately 2 months. More than 750 specimens from 4 arachnid orders, (Amblypygi, Pseudoscorpiones, Scorpiones, Araneae) were collected and identified. We recovered 1 species of amblypygid, 2 species of pseudoscorpions, 1 species of scorpion, and 76 species of spiders. Additionally, we compared species diversity between urban and natural areas. The number of species is relatively low given the proximity to South America, but this likely reflects that collecting only took place for a short time and was opportunistic as opposed to systematic. Nevertheless, we found 25 new records and >20 likely undescribed species for the islands, providing insights into the spider fauna of northern South America and indicating that additional surveys of the area are warranted.
Effects of political instability on the volatility of Palestinian food prices
Ihle, R. ; El-Jafari, Mahmoud Khader ; Cramon-Taubadel, Stephan von - \ 2019
New Medit 18 (2019)3. - ISSN 1594-5685 - p. 59 - 76.
Food prices - MENA - Middle East - Uncertainty - War
Political instabilities and violent political conflict have in recent years risen substantially throughout the world. Especially in the Middle East and North Africa they have grown to decisive factors permanently challenging the livelihoods of millions. We assess whether and to what extent varying intensities of conflict impact economic activity in Palestine which has been subject to substantial violent political conflict for decades. In particular, we analyse the relationship between various intensity levels of political instability measured by conflict-caused fatalities and uncertainty of weekly food prices in the West Bank between 2004 and 2011 using a GARCH model. We consider four food commodities covering vegetables, fruits and animal products. Banana and milk prices are found not to show clustered volatility while onion and pear prices do. The impact of varying conflict intensities on weekly average prices appears to be modest. This might suggest that effects happen on a temporally and geographically more disaggregated scale.
Population recovery changes population composition at a major southern Caribbean juvenile developmental habitat for the green turtle, Chelonia mydas
Zee, Jurjan P. van der; Christianen, Marjolijn J.A. ; Nava, Mabel ; Velez-Zuazo, Ximena ; Hao, Wensi ; Bérubé, Martine ; Lavieren, Hanneke van; Hiwat, Michael ; Berzins, Rachel ; Chevalier, Johan ; Chevallier, Damien ; Lankester, Marie Clélia ; Bjorndal, Karen A. ; Bolten, Alan B. ; Becking, L.E. ; Palsbøll, Per J. - \ 2019
Scientific Reports 9 (2019)1. - ISSN 2045-2322

Understanding the population composition and dynamics of migratory megafauna at key developmental habitats is critical for conservation and management. The present study investigated whether differential recovery of Caribbean green turtle (Chelonia mydas) rookeries influenced population composition at a major juvenile feeding ground in the southern Caribbean (Lac Bay, Bonaire, Caribbean Netherlands) using genetic and demographic analyses. Genetic divergence indicated a strong temporal shift in population composition between 2006–2007 and 2015–2016 (ϕST = 0.101, P < 0.001). Juvenile recruitment (<75.0 cm straight carapace length; SCL) from the north-western Caribbean increased from 12% to 38% while recruitment from the eastern Caribbean region decreased from 46% to 20% between 2006–2007 and 2015–2016. Furthermore, the product of the population growth rate and adult female abundance was a significant predictor for population composition in 2015–2016. Our results may reflect early warning signals of declining reproductive output at eastern Caribbean rookeries, potential displacement effects of smaller rookeries by larger rookeries, and advocate for genetic monitoring as a useful method for monitoring trends in juvenile megafauna. Furthermore, these findings underline the need for adequate conservation of juvenile developmental habitats and a deeper understanding of the interactions between megafaunal population dynamics in different habitats.

Mining on communal land as a new frontier: a case study of the Kunene Region, Namibia
Odendaal, Willem ; Hebinck, Paul - \ 2019
Journal of Land Use Science 14 (2019)1. - ISSN 1747-423X - 20 p.
This paper is about mining under communal ownership which makes this kind of mining a new mining frontier. The newness of the frontier is that it has introduced a series of institutional complexities that is uncommon to artisanal and large-scale mining. Mining companies have to negotiate deals with communities and their leaders to be able to prospect for mineral resources. We also argue that the state’s environmental legislation is poorly harmonised with the prevalent conditions in communal areas where mining is gaining greater importance. Legislation remains silent on the rights of those living on communal land. These rights remain in a state of confusion with often negative effects on the local communities who are exposed to a number of duplicating development programmes and legislative structures. The aim of this paper is to explore the dynamics communal mining in the Kunene Region in north-western Namibia
Hepcidin-guided screen-and-treat interventions against iron-deficiency anaemia in pregnancy: a randomised controlled trial in The Gambia
Bah, Amat ; Muhammad, Abdul Khalie ; Wegmuller, Rita ; Verhoef, Hans ; Goheen, Morgan M. ; Sanyang, Saikou ; Danso, Ebrima ; Sise, Ebrima A. ; Pasricha, Sant Rayn ; Armitage, Andrew E. ; Drakesmith, Hal ; Cross, James H. ; Moore, Sophie E. ; Cerami, Carla ; Prentice, Andrew M. - \ 2019
The Lancet Global Health 7 (2019)11. - ISSN 2214-109X - p. e1564 - e1574.

Background: WHO recommends daily iron supplementation for pregnant women, but adherence is poor because of side-effects, effectiveness is low, and there are concerns about possible harm. The iron-regulatory hormone hepcidin can signal when an individual is ready-and-safe to receive iron. We tested whether a hepcidin-guided screen-and-treat approach to combat iron-deficiency anaemia could achieve equivalent efficacy to universal administration, but with lower exposure to iron. Methods: We did a three-arm, randomised, double-blind, non-inferiority trial in 19 rural communities in the Jarra West and Kiang East districts of The Gambia. Eligible participants were pregnant women aged 18–45 years at between 14 weeks and 22 weeks of gestation. We randomly allocated women to either WHO's recommended regimen (ie, a daily UN University, UNICEF, and WHO international multiple-micronutrient preparation [UNIMMAP] containing 60 mg iron), a 60 mg screen-and-treat approach (ie, daily UNIMMAP containing 60 mg iron for 7 days if weekly hepcidin was <2·5 μg/L or UNIMMAP without iron if hepcidin was ≥2·5 μg/L), or a 30 mg screen-and-treat approach (ie, daily UNIMMAP containing 30 mg iron for 7 days if weekly hepcidin was <2·5 μg/L or UNIMMAP without iron if hepcidin was ≥2·5 μg/L). We used a block design stratified by amount of haemoglobin at enrolment (above and below the median amount of haemoglobin on every enrolment day) and stage of gestation (14–18 weeks vs 19–22 weeks). Participants and investigators were unaware of the random allocation. The primary outcome was the amount of haemoglobin at day 84 and was measured as the difference in haemoglobin in each screen-and-treat group compared with WHO's recommended regimen; the non-inferiority margin was set at −5·0 g/L. The primary outcome was assessed in the per-protocol population, which comprised all women who completed the study. This trial is registered with the ISRCTN registry, number ISRCTN21955180. Findings: Between June 16, 2014, and March 3, 2016, 498 participants were randomised, of whom 167 were allocated to WHO's recommended regimen, 166 were allocated to the 60 mg per day screen-and-treat approach, and 165 were allocated to the 30 mg per day screen-and-treat approach. 78 participants were withdrawn or lost to follow-up during the study; thus, the per-protocol population comprised 140 women assigned to WHO's recommended regimen, 133 allocated to the 60 mg screen-and-treat approach, and 147 allocated to the 30 mg screen-and-treat approach. The screen-and-treat approaches did not exceed the non-inferiority margin. Compared with WHO's recommended regimen, the difference in the amount of haemoglobin at day 84 was −2·2 g/L (95% CI −4·6 to 0·1) with the 60 mg screen-and-treat approach and −2·7 g/L (–5·0 to −0·5) with the 30 mg screen-and-treat approach. Adherence, reported side-effects, and adverse events were similar between the three groups. The most frequent side-effect was stomachache, which was similar in the 60 mg screen-and-treat group (82 cases per 1906 person-weeks) and with WHO's recommended regimen (81 cases per 1974 person-weeks; effect 1·0, 95% CI 0·7 to 1·6); in the 30 mg screen-and-treat group the frequency of stomachache was slightly lower than with WHO's recommended regimen (58 cases per 2009 person-weeks; effect 0·7, 95% CI 0·5 to 1·1). No participants died during the study. Interpretation: The hepcidin-guided screen-and-treat approaches had no advantages over WHO's recommended regimen in terms of adherence, side-effects, or safety outcomes. Our results suggest that the current WHO policy for iron administration to pregnant women should remain unchanged while more effective approaches continue to be sought. Funding: Bill & Melinda Gates Foundation and the UK Medical Research Council.

The impact of networks on the innovative and financial performance of more entrepreneurial versus less entrepreneurial farmers in West Java, Indonesia
Etriya, Etriya ; Scholten, Victor E. ; Wubben, Emiel F.M. ; Omta, S.W.F. - \ 2019
NJAS Wageningen Journal of Life Sciences 89 (2019). - ISSN 1573-5214
Business ties - Entrepreneurship - Financial performance - Innovative performance - Network heterogeneity - Technology ties

Farmers may vary in their response to or anticipation of agrifood market changes, which probably depends on their entrepreneurial degree and networks. This paper aims to investigate the effects of farmers’ entrepreneurial degree and network content (i.e., business ties, technology ties, and network heterogeneity) on farm performance (i.e., innovative performance and financial performance). The data set was gathered through a survey of 262 vegetable farmers in West Java, Indonesia. Our findings reveal that more entrepreneurial farmers (106) have more business ties, technology ties, and heterogeneous networks compared to less entrepreneurial farmers (156). Further analyses using OLS regression confirm that farmers who are more entrepreneurial and have more business ties obtain both enhanced innovative and financial performance, while farmers who link to heterogeneous networks obtain only enhanced innovative performance. Overall, the findings of this study demonstrate that more entrepreneurial farmers with networks that are rich in business ties and diverse contacts have better farm performance.

Nutrition and Income Generation Intervention (NIGI) for Refugees and Host Communities in West-Nile Region, Uganda (2018- 2020) : Inception Phase Report
Pittore, Katherine - \ 2019
Wageningen : Wageningen Centre for Development Innovation (WCDI-19-072 ) - 46 p.
The relevance of connecting sustainable agricultural development with African philosophy
Boogaard, Birgit K. - \ 2019
South African Journal of Philosophy 38 (2019)3. - ISSN 0258-0136 - p. 273 - 286.
Our global food system is complex and philosophers can – or should – pose critical questions about it. One question that deserves particular attention is Western interference in agricultural development in Africa. To today, the Western scientific paradigm forms the basis for mainstream agricultural research and development – with a firm belief in technological solutions and economic progress. It is concerning that African philosophy is a largely unknown field among agricultural scientists and practitioners. The aim of this philosophical essay is therefore to explore the relevance of connecting sustainable agricultural development with African philosophy. The article explores Eurocentric thinking in agricultural research and development and why such thinking can be problematic. In a search for ways to respond to Eurocentrism, I follow Kimmerle, who engaged in intercultural dialogues between African and Western philosophies. Mutually respectful and transformative dialogues can lead to mutual understanding and a more equal relation between Africa and the West, in the sense that this relation becomes more open to African philosophies and less Eurocentric.
Roles of agroforestry in sustainable intensification of small farms and food security for societies in West Africa
Seghieri, J. ; Bastide, B. ; Ingram, V.J. ; Jourdan, C. ; Sanogo, D. - \ 2019
What’s Cooking in Berlin’s Food Policy Kitchen
Hoffmann, Dinah ; Morrow, Oona ; Pohl, Christine - \ 2019
Urban Agriculture Magazine (2019)36. - ISSN 1571-6244 - p. 37 - 39.
After years of silence on municipal food policy in Berlin, actors from civil society, academia, industry and the local senate have come together to discuss the current state and future of Berlin’s food system, and are developing the city’s first urban food strategy. The Ernährungsrat Berlin is the citizen-led urban food policy council working towards food democracy and re-localisation in the Berlin-Brandenburg region.
Recommendation domains to scale out climate change adaptation in cocoa production in Ghana
Bunn, Christian ; Läderach, Peter ; Quaye, Amos ; Muilerman, Sander ; Noponen, Martin R.A. ; Lundy, Mark - \ 2019
Climate Services (2019). - ISSN 2405-8807
Climate impacts - Cocoa - Decision support - Ghana - Recommendation domains - West Africa

Climate change is threatening cocoa production in West Africa and guidance towards site-specific adaptation is required. We developed recommendation domains with common degree of impact requiring incremental, systemic or incremental adaptation effort to provide decision support for interventions to scale out adaptive practices. We used Random Forests to divide the cocoa production belt into four zones with distinct climatic features under current and future climate conditions. To make model results actionable we used an expert validation approach. Cocoa experts evaluated and verified cocoa occurrence data for model input, prioritized climate and soil variables for modeling use and confirmed the validity of the distribution of climate zones. Climate change will reduce the available area for cocoa production in the north due to a shift of the northern transition to the Savanna zone. The current area for cocoa in central Ashanti will remain suitable but will face uncertain climatic conditions. Areas in the Western, Central and Eastern regions will likely become hotter and wetter. Each of these projected impacts will require site-specific adaptation strategies matching the degree of impacts. Failing to prepare may subject rural communities to high risks of losing their livelihoods. Our recommendation domains can support impact specific preparation so that the majority of Ghana's cocoa production area may be sustained despite adverse climatic changes. Institutional and private actors can use our work to scale out locally conceived interventions to alleviate impacts from drought, heat and erratic rainfall.

Extreme spatial heterogeneity in carbonate accretion potential on a Caribbean fringing reef linked to local human disturbance gradients
Bakker, Didier M. ; Duyl, Fleur C. ; Perry, Chris T. ; Meesters, Erik H. - \ 2019
Global Change Biology (2019). - ISSN 1354-1013 - 13 p.
Acropora cervicornis - bioerosion - Bonaire - calcification - carbonate budget - Caribbean - climate change - sea-level rise

The capacity of coral reefs to maintain their structurally complex frameworks andto retain the potential for vertical accretion is vitally important to the persistenceof their ecological functioning and the ecosystem services they sustain. However,datasets to support detailed along‐coast assessments of framework production rates and accretion potential do not presently exist. Here, we estimate, based on gross bioaccretion and bioerosion measures, the carbonate budgets and resultant estimated accretion rates (EAR) of the shallow reef zone of leeward Bonaire – between 5 and 12 m depth – at unique fine spatial resolution along this coast (115 sites). Whilst the fringing reef of Bonaire is often reported to be in a better ecological condition than most sites throughout the wider Caribbean region, our data show that the carbonate budgets of the reefs and derived EAR varied considerably across this ~58 km long fringing reef complex. Some areas, in particular the marine reserves, were indeed still dominated by structurally complex coral communities with high net carbonate production (>10 kg CaCO3 m−2 year−1), high live coral cover and complex structural topography. The majority of the studied sites, however, were defined by relatively low budget states (<2 kg CaCO3 m−2 year−1) or were in a state of net erosion. These data highlight the marked spatial heterogeneity that can occur in budget states, andthus in reef accretion potential, even between quite closely spaced areas of individual reef complexes. This heterogeneity is linked strongly to the degree of localized landbased impacts along the coast, and resultant differences in the abundance of reef framework building coral species. The major impact of this variability is that those sections of reef defined by low‐accretion rates will have limited capacity to maintain their structural integrity and to keep pace with current projections of climate change induced sea‐level rise (SLR), thus posing a threat to reef functioning and biodiversity, potentially leading to trophic cascades. Since many Caribbean reefs are more severely degraded than those found around Bonaire, it is to be expected that the findings presentedhere are rather the rule than the exception, but the study also highlights theneed for similar high spatial resolution (along‐coast) assessments of budget states and accretion rates to meaningfully explore increasing coastal risk at the country level. The findings also more generally underline the significance of reducing local anthropo‐ genic disturbance and restoring framework building coral assemblages. Appropriately focussed local preservation efforts may aid in averting future large‐scale above reef water depth increases on Caribbean coral reefs and will limit the social and economic implications associated with the loss of reef goods and services.

Can timber provision from Amazonian production forests be sustainable?
Piponiot, Camille ; Rödig, Edna ; Putz, Francis E. ; Rutishauser, Ervan ; Sist, Plinio ; Ascarrunz, Nataly ; Blanc, Lilian ; Derroire, Géraldine ; Descroix, Laurent ; Guedes, Marcelino Carneiro ; Coronado, Euridice Honorio ; Huth, Andreas ; Kanashiro, Milton ; Licona, Juan Carlos ; Mazzei, Lucas ; Oliveira, Marcus Vinicio Neves D'; Peña-Claros, Marielos ; Rodney, Ken ; Shenkin, Alexander ; Souza, Cintia Rodrigues De; Vidal, Edson ; West, Thales A.P. ; Wortel, Verginia ; Hérault, Bruno - \ 2019
Environmental Research Letters 14 (2019)6. - ISSN 1748-9318
Amazonia - disturbance - ecosystem recovery - macroecology - Selective logging - tropical forestry

Around 30 Mm3 of sawlogs are extracted annually by selective logging of natural production forests in Amazonia, Earth's most extensive tropical forest. Decisions concerning the management of these production forests will be of major importance for Amazonian forests' fate. To date, no regional assessment of selective logging sustainability supports decision-making. Based on data from 3500 ha of forest inventory plots, our modelling results show that the average periodic harvests of 20 m3 ha-1 will not recover by the end of a standard 30 year cutting cycle. Timber recovery within a cutting cycle is enhanced by commercial acceptance of more species and with the adoption of longer cutting cycles and lower logging intensities. Recovery rates are faster in Western Amazonia than on the Guiana Shield. Our simulations suggest that regardless of cutting cycle duration and logging intensities, selectively logged forests are unlikely to meet timber demands over the long term as timber stocks are predicted to steadily decline. There is thus an urgent need to develop an integrated forest resource management policy that combines active management of production forests with the restoration of degraded and secondary forests for timber production. Without better management, reduced timber harvests and continued timber production declines are unavoidable.

Post-fire soil erosion mitigation at the scale of swales using forest logging residues at a reduced application rate
Prats, Sergio A. ; González-Pelayo, Óscar ; Silva, Flavio C. ; Bokhorst, Koen J. ; Baartman, Jantiene E.M. ; Keizer, Jan J. - \ 2019
Earth Surface Processes and Landforms (2019). - ISSN 0197-9337
effectiveness - erosion - mulch - organic matter - wildfire

Mulching with forest residues has proved to be highly effective in reducing post-fire soil losses at the plot scale. However, its effectiveness has not been quantified at the application rates that are typically used in operational post-fire land management (2–3 Mg ha-1 using straw), as well as at scales larger than 100 m2. The present study compared post-fire erosion rates for six convergent hillslopes or swales of 500 to 800 m2, three of which were left untreated while the other three were mulched immediately after the fire with shredded eucalypt bark at a rate of 2.4 Mg ha-1. Erosion rates were monitored at irregular intervals during the first three post-fire years, whilst ground cover was assessed yearly. Selected topsoil properties (0–2 cm) such as organic matter content and aggregate stability were determined at a single occasion – two years after the wildfire, for three micro-environments separately: bare soil, and under mulch/litter and vegetation. Soil losses on the untreated swales decreased with post-fire year from 2.2 to 0.4 and 0.11 Mg ha-1 yr-1 (respectively for the first, second and third post-fire years), while the mulched swales produced 84%, 77% and 38% less soil losses than the untreated swales. Soil losses also depended on slope aspect, with the north-facing swales producing less erosion than the west-facing ones. This could be linked to their significant differences in bare soil, vegetation and stone cover, or a combination thereof. The type of micro-environment also played a significant role in topsoil properties (stone content, bulk density, resistance to penetration/shear stress, porosity and organic matter content). The present results add to the increasing evidence that forest residues should be duly considered for operational post-fire land management. Forest residues were highly effective in reducing erosion from swales at application rates as low as the typical 2 Mg ha-1 of post-fire straw mulch.

Hydrographic and Biological Survey of a Surface-Intensified Anticyclonic Eddy in the Caribbean Sea
Boog, C.G. van der; Jong, M.F. de; Scheidat, M. ; Leopold, M.F. ; Geelhoed, S.C.V. ; Schulz, K. ; Dijkstra, H.A. ; Pietrzak, J.D. ; Katsman, C.A. - \ 2019
Journal of Geophysical Research: Oceans 124 (2019)8. - ISSN 2169-9275 - p. 6235 - 6251.
anticyclone - barrier layer - Caribbean Sea - ecology - hydrographic - thermohaline staircases

In the Caribbean Sea, mesoscale anticyclonic ocean eddies impact the local ecosystem by mixing of low salinity river outflow with the nutrient-rich waters upwelling along the Venezuelan and Colombian coast. To gain insight into the physics and the ecological impact of these anticyclones, we performed a combined hydrographic and biological survey of one Caribbean anticyclone in February 2018. We found that the anticyclone had a radius of 90 km and was surface intensified with the strongest velocities (0.72 m/s) in the upper 150 m of the water column. Below, isopycnal displacements were found down to 700 dbar. The core of the anticyclone entrained waters from the Orinoco River plume and contained slightly elevated chlorophyll concentrations compared to the surroundings. At the edge of the anticyclone we observed higher densities of flying fish but not higher densities of predators like seabirds and cetaceans. Below the surface, a strong temperature inversion (0.98 °C) was present within a barrier layer. In addition, we found thermohaline staircases that originated from double diffusion processes within Tropical Atlantic Central Water.

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