Sustainable urban drainage systems (SuDS) or nature-based solutions (NBSs) are widely implemented to collect, store and infiltrate stormwater. The buildup of pollutants is expected in NBSs, and Dutch guidelines advise monitoring the topsoil of bio-swales every 5 years. In the Netherlands, almost every municipality has implemented bio-swales. Some municipalities have over 300 bio-swales, and monitoring all their NBSs is challenging due to cost and capacity. In this study, 20 locations where bio-swales with ages ranging between 10 and 20 years old were selected for a field investigation to answer the following question: is the soil quality of bio-swales after 10 years still acceptable? Portable XRF instruments were used to detect potential toxic elements (PTEs) for in situ measurements. The results showed that for copper (Cu), zinc (Zn) and lead (Pb), 30%, 40% and 25% of the locations show values above the threshold and 5%, 20% and 0% above the intervention threshold, meaning immediate action should be taken. The results are of importance for stakeholders in (inter)national cities that implement, maintain, and monitor NBS. Knowledge of stormwater and soil quality related to long-term health risks from NBS enables urban planners to implement the mostappropriate stormwater management strategies. With these research results, the Dutch guidelines for design, construction, and maintenance can be updated, and stakeholders are reminded that the monitoring of green infrastructure should be planned and executed every 5 years.
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Stormwater runoff can contain high amounts of Potential Toxic Elements (PTE) as heavy metals. PTE can have negative and direct impact on the quality of surface waters and groundwater. The European Water Framework Directive (WFD) demands enhanced protection of the aquatic environment. As a consequence, the WFD requires municipalities and water authorities to address the emissions from drainage systems adequately and to take action when these emissions affect the quality of receiving waters together with mitigating the quantity challenges in a changing climate (floodings and drought). NBS is the most widely used method for storing stormwater and infiltrating in the Netherlands. However, there is still too little knowledge about the long-term functioning of the soil of these facilities. The research results are of great importance for all stakeholders in (inter)national cities that are involved in climate adaptation. Applying Nature-Based Solutions (NBS), Sustainable Urban Drainage Systems (SuDS) or Water Sensitive Urban Design (WSUD) are known to improve the water quality in the urban water cycle. The efficiency of NBS, such as the capability of bio swales to trap PTE, highly depends on the dimensions of the facility and on its implementation in the field [Woods Ballard, B et al, 2015]. For the determination of the removal efficiency of NBS information about stormwater quality and characteristics is essential. Acquiring the following information is strongly advised [Boogaard et al. 2014]:1. stormwater quality levels (method: stormwater quality database);2. location of NBS (method: mapping NBS in international database);3. behaviour of pollutants (method: cost effective mapping pollutants in the field). Stormwater quality contains pollutants as heavy metal in higher concentrations than water quality standards dictate. Over 500 locations with bio swales are mapped in the Netherlands which is a fraction of stormwater infiltration locations implemented in 20 years’ time. Monitoring of all these NBS would acquire high capacity and budget from the Dutch resources. This quick scan XRF mapping methodology of topsoil will indicate if the topsoil is polluted and whether the concentrations exceed national or international standards. This was only the case in one of the youngest pilots in Utrecht indicating that there are multiple factors other than age (traffic intensity, use of materials, storage volume, maintenance, run off quality, etc.). Several locations show unacceptable levels, above the national thresholds for pollutants where further research on the prediction of these levels in relation to multiple factors will be the subject of future research.The results of study are shared in 2 national workshops and valued as of great importance for all stakeholders in (inter)national cities that are involved in implementation of NBS for climate adaptation. The Dutch research results will be used to update (inter-)national guidelines for design, construction and maintenance of infiltration facilities this year. Stormwater managers are strongly advised to use this quick scan method within the first 10 years after implementation of swales to map possible pollution of the top soil and prevent pollution to spread to the groundwater in urban areas.
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Sustainable urban drainage systems (SuDS) such as swales are designed to collect, store and infiltrate a large amount of surface runoff water during heavy rainfall. Stormwater is known to transport pollutants, such as particle-bound Potential Toxic Elements (PTE), which are known to often accumulate in the topsoil. A portable XRF instrument (pXRF) is used to provide in situ spatial characterization of soil pollutants, specifically lead (Pb), zink (Zn) and copper (Cu). The method uses pXRF measurements of PTE along profiles with set intervals (1 m) to cover the swale with cross-sections, across the inlet, the deepest point and the outlet. Soil samples are collected, and the In-Situ measurements are verified by the results from laboratory analyses. Stormwater is here shown to be the transporting media for the pollutants, so it is of importance to investigate areas most prone to flooding and infiltration. This quick scan method is time and cost-efficient, easy to execute and the results are comparable to any known (inter)national threshold criteria for polluted soils. The results are of great importance for all stakeholders in cities that are involved in climate adaptation and implementing green infrastructure in urban areas. However, too little is still known about the long-term functioning of the soil-based SuDS facilities.
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Chemical preservation is an important process that prevents foods, personal care products, woods and household products, such as paints and coatings, from undesirable change or decomposition by microbial growth. To date, many different chemical preservatives are commercially available, but they are also associated with health threats and severe negative environmental impact. The demand for novel, safe, and green chemical preservatives is growing, and this process is further accelerated by the European Green Deal. It is expected that by the year of 2050 (or even as soon as 2035), all preservatives that do not meet the ‘safe-by-design’ and ‘biodegradability’ criteria are banned from production and use. To meet these European goals, there is a large need for the development of green, circular, and bio-degradable antimicrobial compounds that can serve as alternatives for the currently available biocidals/ preservatives. Anthocyanins, derived from fruits and flowers, meet these sustainability goals. Furthermore, preliminary research at the Hanze University of Applied Science has confirmed the antimicrobial efficacy of rose and tulip anthocyanin extracts against an array of microbial species. Therefore, these molecules have the potential to serve as novel, sustainable chemical preservatives. In the current project we develop a strategy consisting of fractionation and state-of-the-art characterization methods of individual anthocyanins and subsequent in vitro screening to identify anthocyanin-molecules with potent antimicrobial efficacy for application in paints, coatings and other products. To our knowledge this is the first attempt that combines in-depth chemical characterization of individual anthocyanins in relation to their antimicrobial efficacy. Once developed, this strategy will allow us to single out anthocyanin molecules with antimicrobial properties and give us insight in structure-activity relations of individual anthocyanins. Our approach is the first step towards the development of anthocyanin molecules as novel, circular and biodegradable non-toxic plant-based preservatives.
Plastic products are currently been critically reviewed due to the growing awareness on the related problems, such as the “plastic soup”. EU has introduced a ban for a number of single-use consumer products and fossil-based polymers coming in force in 2021. The list of banned products are expected to be extended, for example for single-use, non-compostable plastics in horticulture and agriculture. Therefore, it is crucial to develop sustainable, biodegradable alternatives. A significant amount of research has been performed on biobased polymers. However, plastics are made from a polymer mixed with other materials, additives, which are essential for the plastics production and performance. Development of biodegradable solutions for these additives is lacking, but is urgently needed. Biocarbon (Biochar), is a high-carbon, fine-grained residue that is produced through pyrolysis processes. This natural product is currently used to produce energy, but the recent research indicate that it has a great potential in enhancing biopolymer properties. The biocarbon-biopolymer composite could provide a much needed fully biodegradable solution. This would be especially interesting in agricultural and horticultural applications, since biocarbon has been found to be effective at retaining water and water-soluble nutrients and to increase micro-organism activity in soil. Biocarbon-biocomposite may also be used for other markets, where biodegradability is essential, including packaging and disposable consumer articles. The BioADD consortium consists of 9 industrial partners, a branch organization and 3 research partners. The partner companies form a complementary team, including biomass providers, pyrolysis technology manufacturers and companies producing products to the relevant markets of horticulture, agriculture and packaging. For each of the companies the successful result from the project will lead to concrete business opportunities. The support of Avans, University of Groningen and Eindhoven University of Technology is essential in developing the know-how and the first product development making the innovation possible.
The climate change and depletion of the world’s raw materials are commonly acknowledged as the biggest societal challenges. Decreasing the energy use and the related use of fossil fuels and fossil based materials is imperative for the future. Currently 40% of the total European energy consumption and about 45% of the CO2 emissions are related to building construction and utilization (EC, 2015). Almost half of this energy is embodied in materials. Developing sustainable materials to find replacement for traditional building materials is therefore an increasingly important issue. Mycelium biocomposites have a high potential to replace the traditional fossil based building materials. Mycelium is the ‘root network’ of mushrooms, which acts as a natural glue to bind biomass. Mycelium grows through the biomass, which functions simultaneously as a growth substrate and a biocomposite matrix. Different organic residual streams such as straw, sawdust or other agricultural waste can be used as substrate, therefore mycelium biocomposites are totally natural, non-toxic, biological materials which can be grown locally and can be composted after usage (Jones et al., 2018). In the “Building On Mycelium” project Avans University of Applied Sciences, HZ University of Applied Sciences, University of Utrecht and the industrial partners will investigate how the locally available organic waste streams can be used to produce mycelium biocomposites with properties, which make them suitable for the building industry. In this project the focus will be on studying the use of the biocomposite as raw materials for the manufacturing of furniture or interior panels (insulation or acoustic).
