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41.
This is the first quantitative study on the prevalence of epizoic Waminoa sp. acoel worms and their association with corals in the Wakatobi Marine National Park (WMNP), South-East Sulawesi, Indonesia. Three replicate transects were laid on the reef crest, flat and slope at six sites in 2006 and eight sites in 2007. Four of the sites were common in both years. In total 69 transects were surveyed in 2006, and 87 transects in 2007. A total of 4.8% of all observed hard corals were associated with acoel worms in 2006 and 2.6% of hard and soft corals in 2007. Acoels were present on 16 and 21 of the coral taxa studied in 2006 and 2007 respectively. The worms were strongly associated with the azooxanthellate coral Tubastrea spp. and were rare or absent on the most abundant coral genera Montipora and Porites. The mean number of corals having acoels was highest on reef slopes, whereas acoels were virtually absent on reef flats. Corals that had a high and a medium cover of worms were more common in 2007 than in 2006. No significant trend in the adaptation of the zooxanthellae of Waminoa sp. to different depths at different sites was revealed. The impact of the worm on the coral is unknown, but high numbers may have a shading effect and a negative impact on the coral’s photophysiology. This acoel merits more study of its life cycle, its photophysiology, and its impact on its host corals. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
42.
ABSTRACT The role of water resources in the urban economic and social environment, particularly in the inner city, has never been established to the degree necessary for making informed decisions on investments in urban waterway and shoreline improvements. The basic tools for measuring psychological and social impacts of waterway and shoreline developments in the inner city have not been fully developed and utilized to date. However, through a detailed analysis of the water resources in the urban core area of Cleveland, it appears that deliberate development of water-based recreation and other environmental resources can lead to improvement in some of the social problems of the inner city. In recreation analysis, there is currently a great gap between methodologies that are conceptually sound and those that have been applied by urban and water-resources planning agencies. New tools and methodologies can only be used successfully when public agencies are given the institutional and policy means for using them equitably in light of social needs. Present urban-water planning practices have been found to be biased against the inner city, often unintentionally.  相似文献   
43.
Ambio - A horizon scan was conducted to identify emerging and intensifying issues for biodiversity conservation in South Africa over the next 5–10 years. South African biodiversity...  相似文献   
44.
A significant element of a community's total air pollution picture is the “state of mind” of the people living in the area with respect to air pollution. The reasons why a study of public attitudes can be an important factor in planning an air pollution control program are briefly summarized. The methodology applied in one such study in the St. Louis Metropolitan area is described, and possible variations related to different scope, objectives and survey area characteristics are suggested.  相似文献   
45.
Considerations for the engineering design of flux force/condensation (FF/C) scrubbers are reviewed. Fine par-ticulate removal in multiple sieve plate FF/C scrubbers is predicted, using mathematical design models. Results of experimental studies of two multiple sieve plate scrubbers for the removal of submicron particles are given. The published experimental data on FF/C scrubber performance are summarized. A preliminary analysis of the economics of FF/C scrubbers, compared to the conventional high energy scrubbers, defines the most favorable operating conditions for the application of FF/C scrubbers.  相似文献   
46.
A flux force/condensation (FF/C) scrubbing system was built to control participate emissions from a secondary metals recovery furnace. Total mass penetration and fractional penetration measurements were made under several different operating modes. The performance of the demonstration scrubber was consistent with the results of previous studies on FF/C scrubbing. The system was generally capable of 90 to 95 % efficiency on particles with a mass median aerodynamic diameter of 0.75 µA. This efficiency was achieved with a 68 cm (27 in.) W.C. gas-phase pressure drop.  相似文献   
47.
The control of fugitive process emissions (FPE) with Spray Charging and Trapping (SCAT) scrubber was evaluated both theoretically and experimentally. The SCAT uses air curtain and/or jets to contain, convey, and divert the FPE into a charged spray scrubber.

Experiments were performed on an 8000 cfm bench-scale spray scrubber to verify the theory and feasibility of collecting fugitive particles with charged water spray. The effects of charge levels on drops and particles, nozzle type, drop size, gas velocity, and liquid/gas ratio on collection efficiency were determined experimentally. The results of the experiments and the comparison between theory and data are presented.

An air curtain was developed for conveying the FPE to the spray scrubber, deflecting the crosswind, and containing hot buoyant plume. The design and air flow field for the air curtain are presented.  相似文献   
48.
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