Ecosystem regimes and responses in a coupled ancient lake system from MIS 5b to present: the diatom record of lakes Ohrid and Prespa

We reconstruct the aquatic ecosystem interactions since the last interglacial period in the oldest, most diverse, hydrologically connected European lake system, by using palaeolimnological diatom and selected geochemistry data from Lake Ohrid “DEEP site” core and equivalent data from Lake Prespa core, Co1215. Driven by climate forcing, the lakes experienced two adaptive cycles during the last 92 ka: "interglacial and interstadial" and "glacial" cycle. The short-term ecosystems reorganizations, e.g. regime shifts within these cycles substantially differ between the lakes, as evident from the inferred amplitudes of variation. The deeper Lake Ohrid shifted between ultra oligo- and oligotrophic regimes in contrast to the much shallower Lake Prespa, which shifted from a deeper, (oligo-) mesotrophic to a shallower, eutrophic lake and vice versa. Due to the high level of ecosystem stability (e.g. trophic state, lake level), Lake Ohrid appears relatively resistant to external forcing, such as climate and environmental change. Recovering in a relatively short time from major climate change, Lake Prespa is a resilient ecosystem. At the DEEP site, the decoupling between the lakes' response to climate change is marked in the prolonged and gradual changes during the MIS 5/4 and 2/1 transitions. These response differences and the lakes' different physical and chemical properties may limit the influence of Lake Prespa on Lake Ohrid. Regime shifts of Lake Ohrid due to potential hydrological change in Lake Prespa are not evident in the data presented here. Moreover, a complete collapse of the ecosystems functionality and loss of their diatom communities did not happen in either lake for the period presented in the study.

Family Models of In(ter)dependence: Cultural Change and the Question of Universal Needs

I will start by discussing some aspects of Kagitcibasi’s Theory of Family Change: its current empirical status and, more importantly, its focus on universal human needs and the consequences of this focus. Family Change Theory’s focus on the universality of the basic human needs of autonomy and relatedness and its culture-level emphasis on cultural norms and family values as reflecting a culture’s capacity for fulfilling its members’ respective needs shows that the theory advocates balanced cultural norms of independence and interdependence. As a normative theory it therefore postulates the necessity of a synthetic family model of emotional interdependence as an alternative to extreme models of total independence and total interdependence. Generalizing from this I will sketch a theoretical model where a dynamic and dialectical process of the fit between individual and culture and between culture and universal human needs and related social practices is central. I will discuss this model using a recent cross-cultural project on implicit theories of self/world and primary/secondary control orientations as an example. Implications for migrating families and acculturating individuals are also discussed.