Segara Anakan, Java, Indonesia, a mangrove-fringed coastal lagoon affected by human activities

The demands of an increasing world population in com-bination with technical advances of mankind, particularlysince industrialisation from the nineteenth centuryonwards, are challenging the natural performance of sys-tem earth. Since then an accelerating loss of biodiversity isaccompanied by an overall decrease of water quality,recovery potential and stability of marine and coastalecosystems (Worm et al. 2006). It has been shown thatregional losses in biodiversity negatively affected ecosys-tem services in temperate estuaries and coastal seas, i.e.they led to a decline in the number of viable fisheries, theprovision of nursery habitats and the filter function ofwetlands, submerged vegetation and suspension feeders(Lotze et al. 2006).This is also of particular importance in coastal regionsof the tropics where a majority of people lives within100 km of the coast and to a large extent economicallydepends on its natural resources. Their overexploitation isendangering ecosystem functioning. Besides providing uswith living natural resources which can be directly valuedby providing either humans with energy or cash via mar-kets, ecosystems also offer a variety of other services suchas, e.g., flood protection, climate and water regulation,nutrient cycling and biological control (Costanza et al.1997), which indirectly also affect the economic potential.The removal of a resource from the system does not onlymean to decrease its directly measurable economic effects,but it may also entail a cascade of effects on the ecosystemstructure and functions.While the depletion of fish stocks, e.g., has direct eco-nomic consequences, i.e. less income for fishermen, theeffect of a missing element in the foodweb on ecosystemfunctioning can only be seen later. This, in turn, mayadversely affect those ecosystem services which are diffi-cult to quantify in terms comparable with economic ser-vices and manufactured capital (Costanza et al. 1997).Because of the difference in timescales of realising thedirect and indirect effects of resource depletion and thedifficulties in valuing ecosystem services in terms ofeconomy, the importance of these ecosystem services haslong been overlooked or given little attention in policydecisions.Only in the past decades, we have learnt that theseecosystem services in the long run sustain the economicpotential of an ecosystem to a large extent. It appears thatcoastal systems with a high biodiversity consistently pro-vide more ecosystem services than those experiencing aloss of diversity. This has to be taken into account withregard to the economic potential and policy decisions.Biodiversity conservation and long-term economic devel-opment can be seen as interdependent societal goals ofequal importance (Worm et al. 2006). Therefore, devel-oping management measures towards a sustainable use ofnatural resources requires an integrated understanding ofecosystem structure and functions and social and economicdynamics of a region, all of which are intimately linked.In this special issue, we present results of the German-Indonesian SPICE (Science for the Protection of Indone-sian Coastal Marine Ecosystems) programme whichaddresses the scientific, social and economic issues relatedto the management of the Indonesian coastal marine