The trophic level impact of structural changes in Aufwuchs communities resulting from low levels of stress can be assessed through analyses of the nutritive value of the microfloral community in conjunction with measurements of grazer consumption rates and assimilation efficiencies. Artificial streams dosed with either intermittent chlorination (20 min doses 3 times per d) or continuous treatments of copper (0.05 ppM) or dextrose (1 or 2 ppM) were used to obtain Aufwuchs communities from stressed environments. Aufwuchs communities were also sampled from the New River within and around a chlorinated-thermal, power plant discharge. The heterotrophically dominated Aufwuchs communities developing under the dextrose enrichment contained more protein, carbohydrate, and calories compared to reference communities. There was no significant change in snail consumption of Aufwuchs from the dextrose enriched streams, although this community was consistently assimilated with greater efficiency relative to reference communities. When Aufwuchs developing under the chlorine or copper treatments became dominated by blue-green algae, the protein content of these communities increased as a result of the algal proteinatious sheath. Carbohydrate content was generally less then reference values for Aufwuchs developing under chlorine or copper stress. Aufwuchs from these treated streams were consumed to a less extent than reference communities and assimilated with 2 to 12% less efficiency
The Amchitka Radiobiological Program is a continuing program to collect biological and environmental samples for radiometric analyses. Results of analyses for samples collected during 1976 include gamma-emitting radionuclides in air filters, freshwater, birds, lichens, marine algae, marine invertebrates, fish, aufwuchs, and freshwater moss and plants; 90Sr in rats, birds, and soil; 239240Pu in sand, soil, marine algae and fish; and tritium (3H) in seawater, freshwater, and biological organisms
Dott, W; Schoenen, D
Refined steel plates coated with different materials that contained available organic compounds led to a microbial growth on the surface. Even plastics and bitumen which were used in the sphere of drinking water showed after an exposure time of three months up to 192 ml slime per square meter. The number of viable bacteria within the Aufwuchs was in the range of 10(7) cfu/ml. The production of slime increased with time. The relation of carbohydrate and protein content significantly changed from 2 at the beginning to 30 after 12 months of incubation the bitumen coating test plates. This indicates an increase synthesis of carbohydrate containing extracellular polymeric substances during the late phase of growth. The bacteria isolated from the Aufwuchs mainly belonged to the genera Pseudomonas, Flavobacterium, Acinetobacter, Caulobacter, sheated bacteria and other gramnegative physiologically nonreactiv roads. During exposure of the plates the relation changed within the bacterial communities of the main groups. Comparing the bacteria communities of inlet and outflow water it became evident that the later one was influenced by bacteria of the Aufwuchs. PMID:4024773
Report on the FY 1999 research survey on the industrial utilization/development of the biofilm formation mechanism and antifouling substances; 1999 nendo bio film keisei kiko oyobi sogai busshitsu no sangyoteki riyo kaihatsu chosa hokokusho
The paper described the results of the FY 1999 research on the fouling by marine aufwuchs. The survey is aimed at searching the nature world for active substances for biological antifouling. The fouling mechanism in the ocean is as follows. The adsorption of organisms called the conditioning film first occurs on the surface, and next, bacteria and diatom around the surface form biofilm and cover. After that, biological fouling by large aufwuchs occurs. Therefore, the control of biofilm formation was regarded as most important, and with this as a guidepost, the search was conducted. Using biofilm anti-formation activity and periphytic bacteria anti-growth activity as guideposts, some compounds were searched for. Being aimed at Porifera, in particular, new compounds were isolated from it. Since few of other organisms attaches on the surface of sponge, there is a great possibility of Porifera's producing any anti-fouling substances. Further, it is thought that symbiotic microorganisms of sponge (40% of the total weight) produce various biologically active substances. Synthetic phenethyl amine derivatives were also studied. (NEDO)
The Amchitka Radiobiological Program began in 1970 and is a continuing program to collect biological and environmental samples for radiometric analyses. This report is an account of the program for calendar year 1978. Results of analyses for samples collected in August 1978 have been added to the tables of Seymour and Johnson (1978) which summarize the Amchitka program from 1970 to 1977 and include analyses for: (1) gamma-emitting radionuclides in freshwater, birds, lichens, marine algae, marine invertebrates, fish, aufwuchs, and freshwater moss and plants; (2) strontium-90 (90Sr) in rats, birds, and soil; (3) 239, 240Pu in sand, soil, marine algae, and fish; and (4) tritium (3H) in seawater, freshwater, and biological organisms. Monitoring of background radiation with survey instruments was added to the Laboratory's program in 1974, and the results of the five annual surveys since that date are included in this report. Conclusions from the results of the recent analyses are a reiteration of the results stated in Nelson and Seymour (1975a); namely, (1) no new radionuclides are present; (2) the most abundant radionuclides are naturally occurring beryllium-7 (7Be) and potassium-40 (40K); (3) the trace quantities of fission products and induced radionuclides are from world fallout; and (4) a trace of 3H contamination remains in some Long Shot ponds, as previously reported. It is concluded that there were no radionuclides of Milrow or Cannikin origin in the water, plants, or animals of Amchitka Island
Koblmüller, Stephan; Egger, Bernd; Sturmbauer, Christian; Sefc, Kristina M
The evolutionary history of the endemic Lake Tanganyika cichlid tribe Tropheini, the sister group of the species flocks of Lake Malawi and the Lake Victoria region, was reconstructed from 2009 bp DNA sequence of two mitochondrial genes (ND2 and control region) and from 1293 AFLP markers. A period of rapid cladogenesis at the onset of the diversification of the Tropheini produced a multitude of specialized, predominantly rock-dwelling aufwuchs-feeders that now dominate in Lake Tanganyika's shallow habitat. Nested within the stenotopic rock-dwellers is a monophyletic group of species, which also utilize more sediment-rich habitat. Most of the extant species date back to at least 0.7 million years ago. Several instances of disagreement between AFLP and mtDNA tree topology are attributed to ancient incomplete lineage sorting, introgression and hybridization. A large degree of correspondence between AFLP clustering and trophic types indicated fewer cases of parallel evolution of trophic ecomorphology than previously inferred from mitochondrial data. PMID:19853055
Farag, A.M.; Nimick, D.A.; Kimball, B.A.; Church, S.E.; Harper, D.D.; Brumbaugh, W.G.
To characterize the partitioning of metals in a stream ecosystem, concentrations of trace metals including As, Cd, Cu, Pb, and Zn were measured in water, colloids, sediment, biofilm (also referred to as aufwuchs), macroinvertebrates, and fish collected from the Boulder River watershed, Montana. Median concentrations of Cd, Cu, and Zn in water throughout the watershed exceeded the U.S. EPA acute and chronic criteria for protection of aquatic life. Concentrations of As, Cd, Cu, Pb, and Zn in sediment were sufficient in the tributaries to cause invertebrate toxicity. The concentrations of As, Cu, Cd, Pb, and Zn in invertebrates from lower Cataract Creek (63, 339, 59, 34, and 2,410 ??g/g dry wt, respectively) were greater than the concentrations in invertebrates from the Clark Fork River watershed, Montana (19, 174, 2.3, 15, and 648 ??g/g, respectively), that were associated with reduced survival, growth, and health of cutthroat trout fed diets composed of those invertebrates. Colloids and biofilm seem to play a critical role in the pathway of metals into the food chain and concentrations of As, Cu, Pb, and Zn in these two components are significantly correlated. We suggest that transfer of metals associated with Fe colloids to biological components of biofilm is an important pathway where metals associated with abiotic components are first available to biotic components. The significant correlations suggest that Cd, Cu, and Zn may move independently to biota (biofilm, invertebrates, or fish tissues) from water and sediment. The possibility exists that Cd, Cu, and Zn concentrations increase in fish tissues as a result of direct contact with water and sediment and indirect exposure through the food chain. However, uptake through the food chain to fish may be more important for As. Although As concentrations in colloids and biofilm were significantly correlated with As water concentrations, As concentrations in fish tissues were not correlated with water. The pathway for
Besser, J.M.; Brumbaugh, W.G.; May, T.W.; Church, S.E.; Kimball, B.A.
The water quality, habitats, and biota of streams in the upper Animas River watershed of Colorado, USA, are affected by metal contamination associated with acid drainage. We determined metal concentrations in components of the food web of the Animas River and its tributaries - periphyton (aufwuchs), benthic invertebrates, and livers of brook trout (Salvelinus fontinalis) - and evaluated pathways of metal exposure and hazards of metal toxicity to stream biota. Concentrations of the toxic metals cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn) in periphyton, benthic invertebrates, and trout livers from one or more sites in the upper Animas River were significantly greater than those from reference sites. Periphyton from sites downstream from mixing zones of acid and neutral waters had elevated concentrations of aluminum (Al) and iron (Fe) reflecting deposition of colloidal Fe and Al oxides, and reduced algal biomass. Metal concentrations in benthic invertebrates reflected differences in feeding habits and body size among taxa, with greatest concentrations of Zn, Cu, and Cd in the small mayfly Rhithrogena, which feeds on periphyton, and greatest concentrations of Pb in the small stonefly Zapada, a detritivore. Concentrations of Zn and Pb decreased across each trophic linkage, whereas concentrations of Cu and Cd were similar across several trophic levels, suggesting that Cu and Cd were more efficiently transferred via dietary exposure. Concentrations of Cu in invertebrates and trout livers were more closely associated with impacts on trout populations and invertebrate communities than were concentrations of Zn, Cd, or Pb. Copper concentrations in livers of brook trout from the upper Animas River were substantially greater than background concentrations and approached levels associated with reduced brook trout populations in field studies and with toxic effects on other salmonids in laboratory studies. These results indicate that bioaccumulation and transfer of
Persistent organic compounds in food chains in Bavaria and Czechia. Pt. 1. Terrestrial systems; Persistente organische Verbindungen in Nahrungsketten von Bayern und Tschechien. T. 1. Terrestrische Systeme
Kettrup, A.; Heinisch, E.
In the paper presented here single presentations concerning the contamination of soil, vegetation and organs and tissues form animals and man with persistent organic substances (DDT and metabolites, isomers of hexachlorocyclohexane, hexachlorobenzene, cyclodiene insecticides, chlorophenols, light volatile organic compounds, PCDD/F, PAH and nitromusk compounds) from Bavaria, the Czech Republic and Brandenburg/Berlin and the former GDR, respectively, were assessed, summarized and - as far as possible - compared and confronted. The results are given in the summaries of the single chapters. It could be shown that the different socioeconomic structures in the regions upto 1989 has considerable influences on the extent of the contamination. Large corpusses of law concerning the application and production of chemical products and their increasingly denser monitoring in Bavaria as well as the various sanitation measures has lead to only traces of chloroorganic compounds now and to a minimization of unavoidable substances like PCDD/F. These prerequisites have now been created in the new federal states - here the example Brandenburg - where upto 1989 the national economy was only directed at production maximization and they begin to result in a decrease of contamination especially for the classical chlorohydrocarbons. In the Czech Republic there are still mostly considerably higher loads, e.g. for HCB and especially for PCB, leading to the consideration of possible bordercrossing effects. (orig.) [Deutsch] In der vorliegenden Arbeit wurden Einzeldarstellungen zur Kontamination von Boden, Aufwuchs und von Tieren bzw. dem Menschen stammenden Organen und Geweben mit persistenten organischen Verbindungen (DDT und Metabolite, Isomeren des Hexachlorcyclohexans, Hexachlorbenzol, Cyclodien-Insektizide, Chlorphenole, leichtfluechtige organische Verbindungen, PCDD/F, PAK und Nitromoschusverbindungen) aus Bayern, Tschechien und Brandenburg-Berlin bzw. der ehemaligen DDR ausgewertet