Management of process performance at low water temperatures in respect of filamentous organisms

The management of sludge-settling properties in Nordic conditions is of importance during the low temperature (spring) season because of the peak settler load. A survey was made in 10 Finnish waste water treatment plants(WWTP‘ s) and the total extended filament length and DSVI in haft of the plants exceeded the limits, which indicates sludge bulking( 15 km/g SS and 150 ml/g respectively). The dominant organism was Microthrix parvicella, the abundance of which was 59.22% of total extended filament length on average.Chemicals were tested to control the filaments, and it was found that special attention has to be paid to maintaining the nitrification at low temperature. A dosage of(H2O2-besed) oxidants controlled the growth of Microthrix parvicella effectively and rapidly, whereas with the use of aluminium hydroxidechloride a 2 to 5-week period was needed to decrease the filament length.     

Landscape Characterization Integrating Expert and Local Spatial Knowledge of Land and Forest Resources

In many developing countries, political documentation acknowledges the crucial elements of participation and spatiality for effective land use planning. However, operative approaches to spatial data inclusion and representation in participatory land management are often lacking. In this paper, we apply and develop an integrated landscape characterization approach to enhance spatial knowledge generation about the complex human–nature interactions in landscapes in the context of Zanzibar, Tanzania. We apply an integrated landscape conceptualization as a theoretical framework where the expert and local knowledge can meet in spatial context. The characterization is based on combining multiple data sources in GIS, and involves local communities and their local spatial knowledge since the beginning into the process. Focusing on the expected information needs for community forest management, our characterization integrates physical landscape features and retrospective landscape change data with place-specific community knowledge collected through participatory GIS techniques. The characterization is established in a map form consisting of four themes and their synthesis. The characterization maps are designed to support intuitive interpretation, express the inherently uncertain nature of the data, and accompanied by photographs to enhance communication. Visual interpretation of the characterization mediates information about the character of areas and places in the studied local landscape, depicting the role of forest resources as part of the landscape entity. We conclude that landscape characterization applied in GIS is a highly potential tool for participatory land and resource management, where spatial argumentation, stakeholder communication, and empowerment are critical issues.     

Quantifying the effects of trampling and habitat edges on forest understory vegetation – A field experiment

We investigated the effects of human trampling on boreal forest understory vegetation on, and off paths from suburban forest edges towards the interiors and on the likelihood of trampling-aided dispersal into the forests for three years by carrying out a trampling experiment. We showed that the vegetation was highly sensitive to trampling. Even low levels of trampling considerably decreased covers of the most abundant species on the paths. Cover decreased between 10 and 30% on paths which had been trampled 35 times, and at least by 50% on those trampled 70–270 times. On-path vegetation cover decreased similarly at forest edges and in the interiors. However, some open habitat plant species that occurred outside the forest patches and at forest edges dispersed into the forests, possibly through the action of trampling. A higher cover percentage of an open habitat species at the forest edge line increased its probability to disperse into the forest interior. The vegetation community on, next to, and away from lightly trampled paths remained the same throughout the trampling experiment. For heavily trampled paths, the community changed drastically on the paths, but stayed relatively similar next to and away from the paths. As boreal vegetation is highly sensitive to the effects of trampling, overall ease of access throughout the forest floor should be restricted to avoid the excessive creation of spontaneous paths. To minimize the effects of trampling, recreational use could be guided to the maintained path network in heavily used areas.     

The role of tending ants in host plant selection and egg parasitism of two facultative myrmecophilous butterflies

Ovipositing adult females of myrmecophilous lycaenids are expected to select plants based on ant presence in order to maximize the survivorship of immature stages. Usually, larvae feed ants with honey-like solutions and, in turn, ants ward off parasitoids. Nonetheless, a rarely investigated approach is whether ant partners can also extend their protective behavior towards lycaenids eggs. Here, we investigated the ant-related oviposition pattern of Allosmaitia strophius and Rekoa marius; then, we compared egg parasitism according to the presence of ants. Lycaenid oviposition and egg parasitism (in percent) were experimentally compared in ant-present and ant-excluded treatments. The study plant, Heteropterys byrsonimifolia, is an extrafloral nectaried shrub which supports several ant species. We sampled 280 eggs, of which 39.65 % belonged to A. strophius and 60.35 % to R. marius. Both lycaenids eggs were significantly more abundant on branches with ants, especially those with Camponotus crassus and Camponotus blandus, two ant species known to attend to lycaenids. A. strophius and R. marius parasitism was 4.5- and 2.4-fold higher, respectively, in ant-present treatments, but the results were not statistically significant. Our study shows that ant-mediated host plant selection in lycaenids might be much more widespread than previously thought, and not restricted to obligate myrmecophilous species. Tending ants may be inefficient bodyguards of lycaenid eggs, because unlike larvae which release sugared liquids, eggs do not offer obvious rewards to ants. Ants can ward off parasitoids of larvae, as observed elsewhere, but our findings show that positive ant–lycaenid interactions are conditional and depend on immature ontogeny.     

Exposure to methylhexahydrophthalic anhydride (MHHPA) in two workplaces of the electric industry

Methylhexahydrophthalic anhydride (MHHPA) is a hardener for hot-cured epoxy resins employed as insulators in the electric industry. MHHPA has only been measured as an ingredient with other alicyclic anhydrides, albeit there are also large processes which use only MHHPA. We collected MHHPA vapour in a set of devices: Teflon filter, glass spiral, TenaxTA tube connected consecutively together. Elution was performed with a solvent mixture of methyl-tert-butyl ether (70%), acetonitrile (30%), and acetic anhydride (0.5%). By capillary GC-ECD, the regression was linear (0.9994) in the practical low concentration range of 0.04-1 microg ml(-1) being equal to 0.001-0.035 mg m(-3) in 30 l of air. The exposure was measured in two factories manufacturing electric appliances. The assembled objects were first impregnated with a liquid epoxy/hardener mixture, and then the resin hardened at elevated temperature. In condenser manufacturing, the operators' 8 h exposure ranged from 0.068 to 0.118 mg m(-3), and the short-term exposure was during operation at ovens mean 1.90 mg m(-3). The impregnation of coiled resistors and transfer of them to ovens caused the worst exposures, short-term mean 3.846 mg m(-3) and long-term mean 2.191 mg m(-3). During the 'baking', the ovens were closed and evacuated, but when the hot objects were moved out of the ovens, they continued during chilling to emit MHHPA, mean 0.366 mg m(-3). In the adjacent areas, assembling, control rooms, offices, the exposure was still significant, 0.017-0.043 mg m(3), due to leaks from the high exposure areas. Mechanical general ventilation and local exhausts were functioning. Respirators were available for short supervising of the hot equipment.     

Photoinduced reduction of divalent mercury in ice by organic matter

Reduction of divalent mercury and subsequent emission to the atmosphere has been identified as loss process from surface snow, but its mechanism and importance are still unclear. The amount of mercury that stays in the snow pack until spring is of significance, because during snow melt it may be released to the aquatic environment and enter the food web. Better knowledge of its fate in snow might further assist the interpretation of ice core data as paleo-archive. Experiments were performed under well-controlled laboratory conditions in a coated wall flow tube at atmospheric pressure and irradiated with light between 300 nm and 420 nm. Our results show that the presence of benzophenone and of oxalic acid significantly enhances the release of mercury from the ice film during irradiation, whereas humic acid is less potent to promote the reduction. Further it was found that oxygen or chloride, and acidic conditions lowered the photolytically induced mercury release in the presence of benzophenone, while the release got larger with increasing temperatures.     

Fate of bisphenol A during treatment with the litter-decomposing fungi Stropharia rugosoannulata and Stropharia coronilla

Bisphenol A is an endocrine disrupting compound, which is ubiquitous in the environment due to its wide use in plastic and resin production. Seven day old cultures of the litter-decomposing fungus Stropharia coronilla removed the estrogenic activity of bisphenol A (BPA) rapidly and enduringly. Treatment of BPA with purified neutral manganese peroxidase (MnP) from this fungus also resulted in 100% reduction of estrogenic activity, as analyzed using a bioluminescent yeast assay, and in the formation of polymeric compounds. In cultures of Stropharia rugosoannulata, estrogenic activity also quickly disappeared but temporarily re-emerged in the further course of cultivation. LC-MS analysis of the extracted estrogenic culture liquid revealed [M−H]⁻ ions with m/z values of 219 and 235. We hypothesize that these compounds are ring fission products of BPA, which still exhibit one intact hydroxyphenyl group to interact with estrogen receptors displayed by the yeast.