Long-Term Community Dynamics of Small Landbirds with and Without Exposure to Extensive Disturbance from Military Training Activities

Military training activities are known to impact individual species, yet our understanding of how such activities influence animal communities is limited. In this study, we used long-term data in a case study approach to examine the extent to which the local small landbird community differed between a site in northeast Kansas that experienced intensive disturbance from military training activities (Ft. Riley Military Installation) and a similar, nearby site that experienced minimal human disturbance (Konza Prairie Biological Station). In addition, we characterized how the regional pool of potential colonizers influenced local community dynamics using Breeding Bird Survey data. From 1991 to 2001, most species of small terrestrial landbirds (73%) recorded during breeding surveys were found at both sites and the mean annual richness at Ft. Riley (39.0 ± 2.86 [SD]) was very similar to that of Konza Prairie (39.4 ± 2.01). Richness was maintained at relatively constant levels despite compositional changes because colonizations compensated local extinctions at both sites. These dynamics were driven primarily by woodland species that exhibited stochastic losses and gains and were present at a low local and regional abundance. Our results suggest that military training activities may mimic natural disturbances for some species in this area because the small landbird community did not differ markedly between sites with and sites without extensive human disturbance. Although our results suggest that military training is not associated with large changes in the avian community, additional studies are needed to determine if this pattern is found in other ecological communities.     

As(III) removal from groundwaters using fixed-bed upflow bioreactors

The application of biological oxidation of iron and manganese, as a potential treatment method for the removal of arsenic from contaminated groundwaters, was examined in this paper. This method was based on the growth of certain species of indigenous bacteria, which are capable of oxidizing the soluble iron and manganese ions; the oxidized forms can be subsequently removed from the aqueous stream by over 97%, through their transformation to insoluble oxides and separation by a suitable filter medium. Arsenic was removed by around 80%, under certain conditions, which were found to be sufficient for Fe(II) removal (dissolved oxygen 2.7 mg/l, redox 280-290 mV, pH 7.2, U 8.25 m/h). The specific treatment technique presents several advantages towards conventional physicochemical treatment methods, such as enhanced coagulation or direct adsorption since: (a) it does not require the addition of other chemicals for oxidizing and removing As(III), (b) it does not require close monitoring of a breakthrough point, as in conventional column adsorption processes and (c) it could find application for the removal of, at least, three groundwater contaminants (Fe, Mn, As).     

Assessing the microbial activity of soil samples,its nutrient limitation and toxic effects of contaminants using a simple respiration test

Eight soil samples from five wells of a former gas plant site differing in the contamination with BTEX and PAHs as well as the nutrient content were investigated by soil respiration measurements. The basal, glucose as well as NH4+ and PO4(3-) induced cumulative oxygen consumption and carbon dioxide production in 72 and 120 h were determined and additionally the maximal turnover rates and the limitation quotients were calculated. Without additional carbon source only one of five investigated samples was clearly nutrient limited. After glucose supplementation four of seven investigated samples showed nutrient limitation that was in accordance with the available ammonium and phosphorous content. BTEX and PAHs did not exhibit an inhibiting effect on the respiration rate. In contrast, BTEX containing samples exhibited the highest oxygen consumption indicating biodegradation of the contaminants. The results show that oxygen consumption and carbon dioxide production as well as the kinetic of these processes are all informative parameters characterizing the whole microbial respiration potential and their nutrient limitation in soil samples. Therefore this fast respirometric method can be used for the decision if further detailed studies of the bioremediation are useful and if nutrient supplementation is recommended to enhance natural attenuation.     

The 1976 outbreak of Hog Cholera in New Jersey: An application of geology to a biological emergency

Hog cholera is a highly contagious virus disease of swine. Since 1962, a Hog Cholera Eradication Program has replaced vaccination as the control mechanism in the U.S. Because the cholera agent requires a live host to thrive, quarantine and herd depopulation are ordered at every U.S. outbreak. The results have been positive and dramatic.The presence of hog cholera was confirmed in Gloucester County, New Jersey, on February 26, 1976. A cooperative State-Federal task force was mobilized to contain and eliminate the infection. Burial would be the disposal technique. For the first time a geologist was requested to augment outbreak control, with responsibility to pinpoint safe burial sites for thousands of animals. USDA emergency policy and procedures limited the options of the assisting geologist, but basic geologic judgments sufficed during appraisals of burial sites. Ultimately, 10 sites were needed and used; other locations proposed during the course of the outbreak were judged hydrogeologically unsuitable and were therefore rejected. Each excavation was sited to minimize potential impact on local aquifers, chiefly by maintaining maximum separation from the water table and by prudent siting within the hydrogeology of the outbreak area.From the first positive confirmation to the end of the active outbreak, a period of four weeks, 15,741 swine totaling over 1 million kg were destroyed and buried. The resulting indemnity was just under $3 million. Because of effective cooperative action during the New Jersey incident, geologic appraisal during large U.S. livestock depopulations now promises to become standard procedure.     

Evidence for a symbiosis between bacteria of the genus Rhodobacter and the marine sponge Halichondria panicea : harbor also for putatively toxic bacteria?

Halichondria panicea (Pallas) is a marine sponge, abundantly occurring in the Adriatic Sea, North Sea, and Baltic Sea. It was the aim of the present study to investigate if this sponge species harbors bacteria. Cross sections through H. panicea were taken and inspected by electron microscopy. The micrographs showed that this sponge species is colonized by bacteria in its mesohyl compartment. To identify the bacteria, polymerase chain reaction (PCR) analysis of the 16S rRNA gene segment, typical for bacteria, was performed. DNA was isolated from sponge material that had been collected near Rovinj (Adriatic Sea), Helgoland (North Sea), and Kiel (Baltic Sea) and was amplified with bacterial primers by PCR. The data gathered indicate that in all samples bacteria belonging to the genus Rhodobacter (Proteobacteria, subdivision α) are dominant, suggesting that these bacteria live in symbiotic relationship with the sponge. In addition, the results show that the different samples taken contain further bacterial species, some of them belonging to the same genus even though found in sponges from different locations. The possibility of the presence of toxic bacteria was supported by the finding that organic extracts prepared from sponge samples displayed toxicity, when analyzed in vitro using leukemia cells. Received: 7 March 1997 / Accepted: 2 October 1997     

Characterisation of agroindustrial solid residues as biofuels and potential application in thermochemical processes

In the present work, selected agroindustrial solid residues from Brazil – biosolids from meat processing wastewater treatment and mixture of sawdust with these biosolids; residues from apple and orange juice industries; sugarcane bagasse; açaí kernels (Euterpe oleracea) and rice husk – were characterised as solid fuels and an evaluation of their properties, including proximate and ultimate composition, energy content, thermal behaviour, composition and fusibility of the ashes was performed. The lower heating value of the biomasses ranged from 14.31 MJ kg^?1 to 29.14 MJ kg^?1, on a dry and ash free basis (daf), all presenting high volatile matter content, varying between 70.57 wt.% and 85.36 wt.% (daf) what improves the thermochemical conversion of the solids. The fouling and slagging tendency of the ashes was predicted based on the fuel ash composition and on the ash fusibility correlations proposed in the literature, which is important to the project and operation of biomass conversion systems. The potential for application of the Brazilian agroindustrial solid residues studied as alternative energy sources in thermochemical processes has been identified, especially concerning direct combustion for steam generation.