A minimal model for predator-prey interaction in a composite environment is presented and analysed. We first consider free migrations between two patches for both interacting populations, and then the particular cases where only one-directional migration is allowed and where only one of the two populations can migrate. Our findings indicate that in all cases the ecosystem can never disappear entirely, under the model assumptions. The predator-free equilibrium and the coexistence of all populations are found to be the only feasible stable equilibria. When there are only one-directional migrations, the abandoned patch cannot be repopulated. Other equilibria then arise, with only prey in the second patch, coexistence in the second patch, or prey in both patches but predators only in the second one. For the case of sedentary prey, with predator migration, the prey cannot thrive alone in either of the two environments. However, predators can survive in a prey-free patch due to their ability to migrate into the other patch, provided prey is present there. If only the prey can migrate, the predators may be eliminated from one patch or from both. In the first case, the patch where there are no predators acts as a refuge for the survival of the prey.

Kefir is a dairy product popular in many countries in Central Europe, especially in Poland and other countries of Eastern and Northern Europe. This type of fermented milk is produced by a complex population of symbiotic bacteria and yeasts. In this work, conditions for DNA extraction, involving disruption of kefir grains and a cascade of cell lysis treatments, were established. Extraction procedure of total microbial DNA was carried out directly from fresh kefir grains. Using different lysis stringency conditions, five DNA pools were obtained. Genetic diversity of DNA pools were validated by RAPD analysis, which showed differences in patterns of amplified DNA fragments, indicating diverse microbial composition of all the analysed samples. These DNA pools were used for construction of genomic DNA libraries for sequencing. As much as 50% of the analysed nucleotide sequences showed homology to sequences from bacteria belonging to the Lactobacillus genus. Several sequences were similar to sequences from bacteria representing Lactococcus, Oenococcus, Pediococcus, Streptococcus and Leuconostoc species. Among homologues of yeast proteins were those from Candida albicans, Candida glabrata, Kluyveromyces lactis and Saccharomyces cerevisiae. In addition, several sequences were found to be homologous to sequences from bacteriophages.

In recent decades, the interconnectedness of history and ecology has received increasing attention. Although necessarily interdisciplinary, efforts to study this interconnectedness had their roots either in the humanities and social sciences or in the natural sciences: scholars have tried either to understand more about nature with the help of history, or, about human history with the help of natural phenomena. As a result, theoretical studies about the integration of ecology and history try to answer two relatively distinct questions: ‘why ecology matters in history’ and ‘why history matters in ecology’. This paper sets out to systematize current knowledge on the latter question and to highlight those issues that have so far received less attention. The arguments can be grouped into three major themes. First, history matters in ecology because it aids understanding of current patterns and processes in nature. Second, because it fosters better informed management and policy decisions; and third, because it places ecology and conservation in a wider interdisciplinary context. Besides dealing with the perspectives of ecologists and conservationists, this paper also includes material from historians, anthropologists and archaeologists, that is, from scholars whose primary interest does not lie in ecological investigations, but who have, nonetheless, embraced the need for the integration of ecology and history.