In recent years, there has been a steady increase in the number of bioretention systems installed worldwide. However, there has only been limited research on the long-term effectiveness of these sustainable urban drainage system devices. This paper presents the results of a series of controlled field experiments investigating the pollutant removal efficiency of three bio-filtration system that have been in service for over five years in the Sunshine Coast in Australia. The results of this study suggest that the long-term pollution removal performance of these systems may not be as effective as previously thought and further research is needed.
Bergen city centre is prone to both subsidence and flooding. With a predicted increase in precipitation due to climate change, a higher proportion of rainfall becomes surface runoff, which results in increased peak flood discharges. In addition, it has been predicted that sea-level rise and increasing storm surges will result in coastal flooding. In this study, the dual hazards of flooding and subsidence are analysed to exemplify possible risk assessment maps for areas most prone to the combination of both. Risk assessment maps are a support tool to identify areas where mitigation of subsidence and adaptation for surface water management will be most efficient and measures can be implemented. The results show that dual hazard assessment, like that described in this paper, can be a useful tool for decision-makers when prioritizing areas to implement measures such as Sustainable Urban Drainage Systems.
MULTIFILE
Peat swamp forests in Southeast Asia are under heavy pressure. Deforestation, forest degradation, wildfires, and drainage have damaged or destroyed substantial areas of the once extensive peat swamp forest formations. Several efforts are underway to rehabilitate degraded peat forests areas in order to restore some of the valuable ecosystem services these forested areas once provided. However, these efforts often result in (mixed)-plantations that only partly resemble the original peat forests. Information about these peat swamp forests' complex origin and ecology is needed to improve restoration outcomes further. Our paper analyses historical data from coastal peat swamp forests in Sarawak and Brunei and discusses the potential to use this as the reference value for intact peat forests. We describe the observed stand structure and species composition for pristine peat swamp forest, and we analyze the population structure of three dominant peat swamp forest species: Gonystylus bancanus (ramin), Dactylocladus stenostachys (jongkong) and Shorea albida (alan batu). We compare the historical data with data from recently measured, degraded peat swamp forests. We discuss our results in relation to processes of peat dome formation, nutrient availability and hydrology, and give recommendations for peat swamp forest management and restoration.
MULTIFILE
Urban open space has a huge impact on human health, well-being and urban ecosystems. One of the open spaces where the environmental and ecological challenges of cities manifest the most is the urban riverfront, often characterised by fragmented land use, lack of accessibility, heavy riverside vehicular traffic, and extreme degradation of river hydrology and ecology. More often than not, the current spatial design of the riverfront hinders rather than supports the delivery of ecosystem services and, in consequence, its potential to improve the health and well-being of urban inhabitants is diminished. Hence, the design of riverside open spaces is crucial. Urban and landscape design in those spaces requires instruments that can aid designers, planners, decision-makers and stakeholders in devising spatial interventions that integrate complex environmental and ecological goals in high quality public space design. By recognising the multiple environmental and ecological benefits of green space and water in the city, the project “I surf” applies a set of four design instruments, namely the Connector, the Sponge, the Integrator, and the Scaler. I surf is a three-phased project that tests, validates and updates these instruments through a design-driven research methodology involving two design workshops and expert meetings addressing three different riverside urban spaces in Amsterdam: in the Ij waterfront, along River Amstel, and on a site located on the canal network. The project concludes with an updated and transferrable instrument set available for urban and landscape design applications in Amsterdam and in other Dutch cities crossed by rivers.
