Watershed processes and their effects on coasts are shaped by numerous interacting natural and societal factors. The knowledge of these factors and processes is often limited. This makes the field prone to politicisations with debates, research, and interventions being confined to a few selected factors. Debates on the causes of high river sediment loads and coastal sedimentation in Java have focussed on rainfed agriculture on peasants' private lands, while other drivers have been neglected. This has undermined the effectiveness of watershed management. This paper links the sedimentation of the Segara Anakan lagoon on Java's south coast with landscape characteristics and transformations in its catchment. Three-fourths of the lagoon have silted up since 1857/60. This is the result of a much broader range of drivers than commonly assumed to date. In addition to rainfed agriculture on peasants' private lands, these drivers include coffee cultivation, timber extraction, plantation development, and in-migration in the late nineteenth and early twentieth century; erosion on contested state forest and plantation lands; state forest management practices; slope cuts to enlarge agricultural fields; agriculture in riparian zones; erosion from roads, trails, and settlements; river channel and floodplain modifications; and volcanic eruptions. The choice and expectations of societal responses aimed at reducing river sediment loads and coastal sedimentation hence need to be reconsidered, and related debates and research agendas must be broadened.

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Historical maps provide large potential for research into historical environmental change. However, the limited availability and accuracy of early cartographic material restricts the analytical time scale of inquiry and poses methodological challenges. An important consideration in this context is the question: at minimum, how accurate must historical maps be in order to be used for which kind of analysis. This question is addressed here, based on the example of a combined analysis of historical maps and satellite images that aimed at reconstructing shoreline aggradation in the Segara Anakan lagoon on the south coast of Java. I present a practical methodological approach to analyzing historical spatial information which has varying degrees of accuracy. In the example presented, this approach links an accuracy assessment of selected historical maps of the region with a lagoon shoreline change analysis. As indicators for the maps’ analytical suitability and the reliability of results, I propose ratios between environmental change rates and quantitative map accuracy measures, as well as combined uncertainty measures. The empirical example demonstrates that in case of large magnitudes of environmental change an analysis of even fairly inaccurate historical maps can provide results with surprisingly low levels of uncertainty. However, large magnitudes of environmental change can also constrain the analysis of historical maps. Quantitative analyses of the accuracy and the contents of historical maps should be accompanied by a qualitative appraisal taking into account carto-bibliographic information and the various dimensions of map accuracy. The maps of change presented in this paper may support further inquiry into the dynamics and drivers of environmental change in the Segara Anakan lagoon region.

Java's extensive political forests and their contentious social relations have been profoundly transformed since the turn of the 21 st century. This paper analyses new forms of forest land use, control, and revenue distribution, shaping and shaped by political-economic changes and neoliberal-era reforms. Villagers' expanded uses, access to, and control of the forest understory under the violently thinned out canopies of the main tree species has generated newly spatialised forest politics, with new institutions and forest labour practices. The changes in land, species, and labour controls, and in villagers' access to forest products and revenues define this historical transformation in the constitution of Java's classic political forest. Contentious co-production has resulted in fragmented territories and a momentary (at least) weakening of state controls within the old imperial political forest.