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Contributions of experimental approaches to development and poverty alleviation : Field experiments and humanitarian assistance
No full textThe work of Nobel Laureates Banerjee, Duflo and Kremer has centered around the use of randomized control trials to help solve development problems. To date, however, few field experiments have been undertaken to evaluate the effects of humanitarian assistance. The reasons may lie in challenges related to logistics, fragility, security and ethics that often loom large in humanitarian settings. Yet every year, billions of dollars are spent on humanitarian aid, and policymakers are in need of rigorous evidence. In this paper, we reflect on the opportunities and risks of running experiments in humanitarian settings, and provide, as illustration, insights from our experiences with recent field experiments of large-scale humanitarian aid programs in the Democratic Republic of Congo.</p
Relating oral physiology and anatomy of consumers varying in age, gender and ethnicity to food oral processing behavior
No full textThe aim of this study was to link parameters describing oral physiology and anatomy of consumers varying in age, gender and ethnicity to food oral processing behavior. Three groups of healthy consumers were compared: Dutch, Caucasian adults (18–30 yrs, n =32), Chinese, Asian adults (18–30 yrs, n =32) and Dutch, Caucasian older adults (65–85 yrs, n =32). Mastication performance, salivary flow rate (stimulated and unstimulated) and dental status were quantified to characterize oral physiology. Volume of oral cavity, tongue dimensions, facial anthropometry, height and weight were quantified to characterize anatomy. Oral processing behavior of three solid foods (carrot, cheese and sausage) was quantified by video recordings and eating rate (g/s), average consumption time (s), chews per bite (-) and average bite size (g) were determined. Dutch, Caucasian older adults had smaller volume of oral cavity, lower number of teeth and larger head width compared to Dutch, Caucasian adults. Chinese, Asian adults showed significantly higher mastication performance and larger head width compared to Dutch, Caucasian consumers, while dental status did not significantly differ between groups. Males had significantly larger volumes of oral cavity and larger head height and width compared to females. Dutch, Caucasian adults had a shorter average consumption time (s), less chews per bite and consumed the three foods with higher eating rate (g/s) compared to Dutch, Caucasian older adults. Chinese, Asian adults had a significantly longer average consumption time (s), more chews per bite, smaller average bite size (g) and lower eating rate (g/s) compared to Dutch, Caucasian adults. Twenty-one significant relationships were found between oral physiological and anatomical parameters and oral processing behavior. Body weight resulted in the largest β-values, indicating to be the anatomical parameter of largest influence on oral processing behavior. We conclude that only few oral physiological and anatomical parameters related with food oral processing behavior. We suggest that other factors, including cultural factors contribute to variation in food oral processing behavior between different consumer groups more than saliva flow, volume of oral cavity, mastication performance and dental status.</p
Identifying and Quantifying the Abundance of Economically Important Palms in Tropical Moist Forest Using UAV Imagery
No full textSustainable management of non-timber forest products such as palm fruits is crucial for the long-term conservation of intact forest. A major limitation to expanding sustainable management of palms has been the need for precise information about the resources at scales of tens to hundreds of hectares, while typical ground-based surveys only sample small areas. In recent years, small unmanned aerial vehicles (UAVs) have become an important tool for mapping forest areas as they are cheap and easy to transport, and they provide high spatial resolution imagery of remote areas. We developed an object-based classification workflow for RGB UAV imagery which aims to identify and delineate palm tree crowns in the tropical rainforest by combining image processing and GIS functionalities using color and textural information in an integrative way to show one of the potential uses of UAVs in tropical forests. Ten permanent forest plots with 1170 reference palm trees were assessed from October to December 2017. The results indicate that palm tree crowns could be clearly identified and, in some cases, quantified following the workflow. The best results were obtained using the random forest classifier with an 85% overall accuracy and 0.82 kappa index
A PXY-Mediated Transcriptional Network Integrates Signaling Mechanisms to Control Vascular Development in Arabidopsis
No full textVascular meristems generate the majority of biomass in higher plants. They constitute a bifacial stem cell population from which xylem and phloem are specified on opposing sides by positional signals. The PHLOEM INTERCALATED WITH XYLEM (PXY) receptor kinase promotes vascular cell division and organisation. However, how these functions are specified and integrated is unknown. Here, a putative PXY-mediated transcriptional regulatory network comprised of 690 transcription factor-promoter interactions was mapped. Among these interactions was a feed-forward loop containing transcription factors WUSCHEL HOMEOBOX RELATED 14 (WOX14) and TARGET OF MONOPTEROS 6 (TMO6), which each regulate the expression of a third transcription factor, LATERAL ORGAN BOUNDARIES DOMAIN 4 (LBD4). PXY signalling in turn regulates the WOX14, TMO6, LBD4 loop to control vascular proliferation. Genetic interaction between LBD4 and PXY suggests that LBD4 marks the phloem-procambium boundary, thus defining the shape of the vascular bundle. These data collectively support a novel mechanism that influences recruitment of cells into the phloem lineage, and defines the role of PXY signalling in this context to the arrangement of vascular tissue
Towards performance assessment of subnational forest-based climate change mitigation initiatives
No full textTropical forests play a central role in reaching the climate change mitigation goals of the Paris agreement. Over the last decade, hundreds of subnational initiatives that aim to reduce deforestation related emissions (REDD+) have been implemented across the tropics which need to be evaluated and monitored. This makes it important to develop and compare different approaches to quantifying impacts on carbon emissions and associated socio-economic trade-offs and synergies. This thesis compared methods that assess deforestation before and after the start of REDD+, in- and outside REDD+ initiatives, and across different scales. These assessments require (spatial) data on forest area and changes therein, but these data contain uncertainties which influence the REDD+ evaluation results. These uncertainties need to be accounted for in REDD+ assessments. The causes of deforestation differ across and within the different study sites, thus calling for locally tailored approaches when designing REDD+ interventions. Apart from the outcomes of these interventions on forest change, well-being outcomes need to be addressed and assessed too in order not to harm forest-dependent livelihoods
Building local support for a coastal protected area : Collaborative governance in the Bigi Pan Multiple Use Management Area of Suriname
No full textBigi Pan Multiple Use Management Area (MUMA, IUCN category VI) is a coastal protected area situated in the Northwest Suriname between the Atlantic Ocean and the Nickerie River. The area is characterized by wetlands with mangrove forests, contains high biodiversity, and is of socio-economic, ecological and ornithological importance. However, the MUMA is overexploited and subject to competition between various income generating activities, including uncontrolled fisheries and unregulated tourism combined. Insufficient capacity of government agencies for enforcement and policy implementation and lack of communication between relevant government agencies has further contributed to unsustainable practices that diverge from ‘wise use’ and conservation. This article analyses the case of Bigi Pan MUMA from the perspective of collaborative governance. It explores how local communities address the conflicts, user pressure, and implementation gaps that lead to unsustainable practices in Bigi Pan MUMA. In addition, it explores the potential of stakeholder engagement with the local community and key user groups to provide meaningful and regular opportunities to actively participate in decision-making structures and to deliberate on management actions. The conclusion finally presents arguments on how collaborative governance can become more effective by including local communities and by strengthening local decision-making and management.</p
TERRAenVISION: Science for Society. Environmental issues today
No full textOur Planet suffers from human activities. As scientists, we know more and more about our environment, about processes, rates of change, new threats, and risks. However, the challenges we face seem to grow quicker than the solutions we can create. To achieve sustainability, the key is to make solutions not only functional from an environmental point of view, but also socially acceptable and economically viable. In this context, the TERRAenVISION conference series gathers diverse groups of scientists to discuss sustainability. The first TERRAenVISION meeting in January 2018 was framed around 7 themes: (1) Climate Change: Mitigation and Adaptation, (2) Water Resources: Quality and Quantity, (3) Land Degradation and Restoration, (4) Nature-based Solutions, (5) Fire in the Earth System, Effects, and Prevention, (6) Ecosystem Services and Health, and (7) Science Interface with Policy and Public. Among the works presented in the conference, this Special Issue collates 22 papers that illustrate the best, problems and solutions the scientific community is currently working on to achieve sustainability. Similar to the concept of the SDGs, paper subjects often intertwine and bridge the conference themes. The papers are grouped in two main chapters dealing with Water and Land, with two additional cross cutting chapters of Scientific Tools and Science-Policy Interface. Drawing from the conclusions of these works as well as those of the TERRAenVISION 2018 conference, we make recommendations regarding raising awareness, connecting scientific fields, and supporting robust economic and policy transitions.</p
Revealing the nutrient limitation and cycling for microbes under forest management practices in the Loess Plateau – Ecological stoichiometry
No full textForest management practices are commonly used in plantation forestry to obtain renewable energy and harvest biomass, in addition to maintaining the ecological environment, by changing the flow of carbon (C) and nutrients in the food webs of terrestrial ecosystems. To identify which forest management practices, alleviate soil nutrient limitation and impact stoichiometric homeostasis in relation to microbes, we used a Pinus tabuliformis plantation in the Loess Plateau where forest management practices were conducted since 1999. Five forest management practices were implemented: two at the forest level (P. tabuliformis with and without ground litter, CK, LRL) and three of different vegetation restorations after clear-cutting (P. tabuliformis seedlings (SPL), grass land (GL), and shrub land (SL)). Generally, the threshold elemental ratios for carbon:nitrogen (TERC:N; 7.77) and carbon:phosphorus (TERC:P; 44.37) were lower than the ratios influenced by forest management practices. The forest management practices significantly influenced ecoenzymatic activity and the ratios of ecoenzymes; however, the scale of the ecoenzyme activities for acquiring both organic N and organic P to that for acquiring C still follow the global pattern. The regression coefficients of C:N and C:P between the soil and microbial community at 0–20 cm and 20–40 cm depths were also influenced by these practices. Thus, the influence of forest management practices on the soil microbial community was limited by N and P in the Loess Plateau. The soil microbial community changed ecoenzymatic activities and ratios of ecoenzymes and even changed microbial community in order to balance elemental limitations in the soil. Finally, forest management practices have a minimal impact on the stoichiometric homeostasis of the microbial community at our study site.</p
The effects of the name “genomics” on emerging attitudes in the Netherlands and Ukraine
No full textPublic opinion is important for the success of a plant breeding practice. Currently, the relatively new practice of genomics-accelerated breeding is under development. From initial findings in research on consumer acceptance, it appears that people experience a strong link between genetic manipulation (GM) and genomics-accelerated breeding after hearing the name “genomics,” leading to an unfavourable evaluation of genomics-accelerated breeding. There are indications that when genomics is presented with the purpose of enhancing food production, the negative link with GM is perceived more readily than when it is presented for other purposes. In the current article, we conduct experiments with the purpose of studying the transference of unfavourable attitudes from GM to genomics-accelerated breeding. The main focus is to investigate if this transfer is influenced by the presented purpose of plant breeding, resp. enhancing food or biofuel production. The results show that universally respondents use their attitudes towards GM to evaluate genomics. In a culture where GM is perceived as controversial (Ukraine), more favourable attitudes towards both practices result when presenting GM in relation to biofuel rather than to food.</p