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To minimize the sediment flowing to the outlet of a river catchment with minimal effort or cost, the best areas to perform a certain intervention, e.g., afforestation, must be selected. CAMF is a method that performs this selection process iteratively in a raster geo-database. The original version of CAMF uses a Single Flow Direction (SFD) algorithm to simulate the flow paths. Although SFD is often used in studies related to hydrological applications, it may fail to reflect the nature of flow transport, depending on the topography. This paper describes and analyzes the integration of Multiple Flow Direction (MFD) methods in CAMF, in order to provide more accurate flow simulations in areas with specific topographic characteristics. We compare the computational complexity of CAMF-SFD and CAMF-MFD using two methods: FD8 and D∞, and we discuss the scalability w.r.t. the number of cells involved. We evaluate the behavior of these three variants for sediment yield minimization by afforestation in two catchments with different properties.

Monitoring and planning processes related to land use management in a spatial context, considering spatial interaction over time, always necessitate complex human decisions. Spatio-temporal decisions are about evaluating alternative answers to a variety of questions that can be categorized as “how?”, “when?”, “how long?”, “what?” and “what if?” questions. A decision in whatever planning process is a commitment to action, is goal specific and has to do with prediction of the future effects of the choices made. Some of the questions that guide spatial intervention planning can be answered using the analytical functionalities of standard GIS-software. However, when optimisation in the presence of multiple goals and criteria are at stake, spatial analysis needs to be complemented with adapted ranking and multicriteria evaluation techniques. In the last decades, worldwide efforts have contributed to a common language in spatiotemporal decision support. From the development of spatiotemporal decision support systems for forestry planning in South American and European context, a theoretical framework and a generic spatiotemporal Decision Support System (stDSS) generator tool were proposed. From this shared experience, the present short paper offers a view on the monitoring and planning needs as raised by the World Heritage City Preservation Management project vlirCPM, for human settlements in the Southern Andes of Ecuador. The main conclusion is that in order to define the requirements of decision support, practical goals and temporal scope must be very clear. Decision support system design, data management and complexity depend on proper formulation and stakeholder consensus on the questions, values and criteria to be handled by planning support tools. No computerized decision support tool will replace multi-actor decision making and has to be complemented and integrated with expert knowledge, multidirectional communication flows and documentation in order to offer a fle

Preservation of cultural heritage is progressively linked to regular maintenance and a continuous monitoring; both activities will define what is known as preventive conservation. This paper discusses the design of a conceptual model for a heritage monitoring system as a support to preventive conservation practices in World Heritage Properties. With respect to these properties the design of the proposed system starts by the choice of a data model, which is determined by different requirements. In heritage conservation, these requests are based on the values and attributes of analyzed elements. They will allow to the system the act of measuring change in the state, number or values presence. Within this framework, a conceptual model is proposed, showing how values and characteristics of heritage elements can be translated into data requirements, how these data requirements define a data model, how this data model determines the database to finally established , how the database determines the best choice for a Geographic Information System (GIS). The paper was illustrated for building blocks in Cuenca and it gives an insight into requirements and potentials of a heritage monitoring system able to combine complex information in spatial reference system valuable to public administration (site managers) for more informed decision making and management strategies. For Cuenca and other world heritage sites, the link made between technology (databases + GIS) and heritage requirements has the objective to overcome the existing gaps and to promote a more nimble heritage management.