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The abundant evapotranspiration provided by the Amazon forests is an important component of the hydrological cycle both regionally and globally. Since the last century, deforestation and expanding agricultural activities have changed the ecosystem and its provision of moisture to the atmosphere. However, it remains uncertain how the ongoing land use change will influence the rainfall, runoff, and water availability as findings from previous studies differ. Using moisture tracking experiments based on observational data, we provide a spatially detailed analysis recognising potential teleconnection between source and sink regions of atmospheric moisture. We apply land use scenarios in upwind moisture sources and quantify the corresponding rainfall and runoff changes in downwind moisture sinks. We find spatially varying responses of water regimes to land use changes which may explain the diverse results from previous studies. Parts of the Peruvian Amazon and western Bolivia are identified as those sink areas most sensitive to land use change in the Amazon and we highlight the current water stress by Amazonian land use change on these areas in the water availability. Furthermore, we also identify the influential source areas where land use change may considerably reduce a given target sink's water reception (from our example of the Ucayali river basin outlet, rainfall by 5–12 % and runoff by 19–50 % according to scenarios). Sensitive sinks and influential sources are therefore suggested as hotspots for achieving sustainable land–water management.

The authors contribute to the discussion on suburban developments by way of modeling the underlying social dynamics between suburban actors in two European suburban areas: the Wirral (Liverpool), UK and Leipzig, Germany. Data from questionnaires carried out in the two study areas are used to model social attraction and repulsion: that is, social segregation processes among socioeconomic groups. The model suggests that these social dynamics would, if other possible influences are ignored, lead to a situation of fluctuating residential in-migration and out-migration and to waves of suburbanization in the study regions. There are no persistent states: suburbanization would steadily continue until external—that is, not modeled—forces restrict movement, impact the spatial characteristics of the suburbs, or alter the social interactions among the actors. Suburban in-migration could only be reduced by strict planning regulations and/or other external forces which impact actor-class constellations and interdependencies, for example, by measures to restrict migration to more distant suburban locations and to provide preferential housing in the inner urban areas. The analysis further indicates that suburbs develop into independent residential areas, separate from the urban centers, as the primary source of migration to suburbs is no longer the urban centers; the vast majority of moves occur within suburbs or into suburbs from outside the region. Keywords: social interaction, segregation, (post-) suburbanization, sprawl, shrinking cities, qualitative modeling, Leipzig, Germany, the Wirral (Liverpool), UK