A substantial fraction of marine plastic debris originates from land-based sources and rivers potentially act as a major transport pathway for all sizes of plastic debris. We analyzed a global compilation of data on plastic debris in the water column across a wide range of river sizes. Plastic debris loads, both microplastic (particles <5 mm) and macroplastic (particles >5 mm) are positively related to the mismanaged plastic waste (MMPW) generated in the river catchments. This relationship is nonlinear where large rivers with  population-rich catchments delivering a disproportionately higher fraction of MMPW into the sea. The 10 top-ranked rivers transport 88-95% of the global load into the sea. Using MMPW as a predictor we calculate the global plastic debris inputs form rivers into the sea to range between 0.41 and 4 × 10 t/y. Due to the limited amount of data high uncertainties were expected and ultimately confirmed. The empirical analysis to quantify plastic loads in rivers can be extended easily by additional potential predictors other than MMPW, for example, hydrological conditions.

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Abstract. Nowadays, the three-dimensional visualization of cities is becoming feasible and popular. The applications serve key sectors of urban development including architecture and urban planning. The implementation of BIM in the geospatial environment will help in evaluation of the design proposals by answering questions such as “What windows have views of a particular spot?”, “How will a design proposal affect views and shadows in an urban scene?” from multiple stakeholder perspectives.This paper presents an approach that facilitates the integration of BIM and geo visualization. 3DCityDB4BIM is a concept for combining existing open source software and open specifications for efficient data management and visualization of Building Information within its broader context. 3DCityDB4BIM core components are the 3DCityDB, the BIMServer, CesiumJS viewer, and the existing standards (glTF, CityGML and IFC). The paper presents the procedure used to enable the development of this new expert system as applied to the context of 3D Web GIS. A thorough analysis of the strengths and weaknesses of these different components has been undertaken to employ their strengths and overcome their weaknesses. The system architecture is providing an extension to the 3DCityDB linking to BIMServer without violating indoor information privacy issues. The 3D visualization format glTF works as the integration medium to visualize BIM and CityGML data in web browsers without plugins or other additional software on the client side. The developed software is open source.