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Zużyte polimery - dostępne i perspektywiczne źródła surowcowe dla procesów recyklingu

Rejewski P., Kijeński J.

Polimery

2010

T. 55, nr 10

711-717

Przedstawiono wyniki analizy i ocen modeli bilansowych (szacunkowego, skorygowanego i zaawansowanego dynamicznego) łańcucha przemian polimerów w gospodarce krajowej "od produktu do odpadu poużytkowego". Bilanse te, aczkolwiek wykazuję zadowalającą zgodność, charakteryzują się znacznym poziomem niepewności nie tylko w Polsce, lecz i w UE. Jest to spowodowane zarówno dynamicznym charakterem takich przemian, jak i różnymi parametrami segmentacji rynku polimerów w ich przemysłowych i końcowych zastosowaniach. Istnieją również istotne różnice we wzajemnych relacjach producentów, przetwórców, konsumentów oraz środowiska odbiorców polimerów zużytych. Podano podstawowe rezultaty oceny aktualnej dostępności surowcowej odpadów polimerowych w Polsce wraz z długoterminową prognozą.

An analysis and the evaluation of balance models (static-approximate, corrected and dynamic-advanced) of polymer transformation chain "from products to post-consumer waste in the local economy has been presented. The balance for the polymer economy, though in good agreement, is characterized by a high level of uncertainty not only for Poland, but also for the EU (Tables 1-4, Fig. 2). This has been the result not only of the dynamic character of changes taking place, but also of the different fragmentation factors in the market concerning industrial and consumer applications. Moreover, there is also the issue of crucial difficulties in the mutual relationship between manufacturers, processing facilities, consumers and the waste polymer processing facilities. The general situation, with special consideration of the current availability of waste polymers for applications as raw materials in Poland and a long-term prognosis has been presented.

Biodiversity of freshwater microorganisms - achievements, problems, and perspectives

Weisse Thomas

Polish Journal of Ecology

2006

Vol. 54, nr 4

633-652

The extent and significance of the diversity of freshwater microbes is at present controversially debated. Until 1980 it was assumed that there are no freshwater-specific bacteria and that the total number of bacterial species is low. The advent of molecular tools over the last ten years revealed that there is a bacterial freshwater assemblage which is phylogenetically different from soil and marine bacteria; secondly, it became obvious that the total number of cultured bacterial species ([similar to] 5900) underestimates bacterial diversity by several orders of magnitude. The current debate centres on 1) how to define a bacterial species and 2) if there is a microbial biogeography. The latter relates to the issue of ubiquity and cosmopolitanism, which is controversially discussed primarily in relation to eukaryotic microorganisms, namely ciliates. Although solid evidence is scarce, many microbial ecologists assume, in accordance with Baas Becking's famous 70-year old dictum - "everything is everywhere, the environment selects" - that freshwater microorganisms are easily dispersed and, therefore, potentially cosmopolitan. This review focuses on the often neglected second part of Baas Becking's metaphor. Evidence is accumulating rapidly that the environment does not simply act as a filter sensu Gleason's individualistic concept for widely dispersed microbes. Rather, prokaryotic and eukaryotic microorganisms have adapted to their specific habitat and perform better in this environment than newly invading congeners. There is an enormous ecophysiological diversity among closely related freshwater microbes which is neither obvious at the morphospecies level nor at the level of evolutionarily conserved genes, such as the small ribosomal RNA gene. Although this large diversity has been demonstrated for various groups of bacteria and protists, there is currently no measure available to compare microbial biodiversity across prokaryotic and eukaryotic domains. The current challenge is to link genetic divergence to ecophysiological diversity in the major taxa.