Sediment transport over sills at longitudinal training dams with unaligned main flow

Longitudinal training dams (LTDs) are  constructed in the River Waal in the  Netherlands. They are aligned parallel to the  river shore and divide the river into a main and  side channel. The existing groynes are  removed yielding more discharge capacity at  high flows. The side channel creates possibly a  sheltered environment for species compared to  the traditional groyne field (Collas, 2014).  Although the lay-out of the LTDs has been  extensively studied using numerical models  (e.g. Huthoff et al., 2011), the morphodynamic  response is yet unclear and depends strongly  on the dimensions (length and height) of the  openings. The inlet and openings (see Fig. 1)  are sill-type structures which can be changed  relatively easy.  These sills are designed in such a way that  they serve as a barrier for water and bed load  sediment. To make long-term morphological  predictions, it is necessary to understand the  bed load transport processes over these sills.  Suspended sediment transport is not  considered in this study. We developed an  analytical model to predict sediment transport  paths on a slope, using a correction on the  well-known critical Shields parameter.  A.J.F. Hoitink, T.V. de Ruijsscher, T.J. Geertsema, B. Makaske, J. Wallinga, J.H.J. Candel, J. Poelman (Eds.) NCR days 2017, Febr. 1-3, 2017. Book of abstracts, NCR publication 41-2017.Rivers, Ports, Waterways and Dredging EngineeringEnvironmental Fluid Mechanic

Planting seeds for the future of food

The health and wellbeing of future generations will depend on humankind's ability to deliver sufficient nutritious food to a world population in excess of 9 billion. Feeding this many people by 2050 will require science-based solutions that address sustainable agricultural productivity and enable healthful dietary patterns in a more globally equitable way. This topic was the focus of a multi-disciplinary international conference hosted by Nestlé in June 2015, and provides the inspiration for the present article. The conference brought together a diverse range of expertise and organisations from the developing and industrialised world, all with a common interest in safeguarding the future of food. This article provides a snapshot of three of the recurring topics that were discussed during this conference: soil health, plant science and the future of farming practice. Crop plants and their cultivation are the fundamental building blocks for a food secure world. Whether these are grown for food or feed for livestock, they are the foundation of food and nutrient security. Many of the challenges for the future of food will be faced where the crops are grown—on the farm. Farmers need to plant the right crops and create the right conditions to maximise productivity (yield) and quality (e.g. nutritional content), whilst maintaining the environment, and earning a living. New advances in science and technology can provide the tools and know-how that will, together with a more entrepreneurial approach, help farmers to meet the inexorable demand for the sustainable production of nutritious foods for future generations