1,398 research outputs found
The effect of land use on benthic communities in Hawkes Bay streams of differing geology : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Ecology at Massey University
Benthic macroinvertebrate and periphyton communities of streams draining four different land use types within four distinct geological types were sampled between December 1996 and January 1997. Catchment land use comprised either standing mature or logged exotic forest, native forest, or hill country pasture. The geological types of these catchments were either Mesozoic sandstone-greywacke, Pleistocene-greywacke, Tertiary mudstone, or limestone in origin. Pastoral stream invertebrate community structure was significantly different from that found in forested streams, with no clear distinction separating communities from standing exotic, logged exotic, and native forest sites. Pastoral communities were dominated by dipterans and trichopterans. while in contrast, macroinvertebrate communities in streams draining sandstone-greywacke catchments were dominated by ephemeropterans and plecopterans, showing a clear influence of catchment geology on benthic macroinvertebrate communities. This sandstone-greywacke effect appeared to be independent of land use. Periphyton biomass was greatest in pastoral and exotic sites, particularly those draining limestone catchments. High nutrient and conductivity levels, both of which are characteristic of limestone streams, appeared to override the effect of light restrictions on periphyton growth in exotic forest sites. Overall, both geology and land use played major roles in determining the structure of stream benthic communities, with factors such as altitude and stream temperature also important influences on these communities. In November and December 1997, nutrient, shade, and disturbance effects were examined in periphyton communities colonising artificial substrates. These substrates were left in the 8 forested Hawkes Bay streams for 28 days with disturbance treatment substrates being physically abraded every 7 days. Nutrients (N + P) were added to nutrient treatment substrates and polythene cloth was used to create an artificially shaded environment for shade treatment substrates. Light availability and percentage canopy cover had the greatest effect upon periphyton, with light limitation being exhibited in closed canopy systems. Nutrient supply was also a factor determining periphyton biomass at both open and closed sites, although only up to a limit. Physical disturbance successfully removed organic matter from substrates as well as reducing chlorophyll a levels at open sites, however light and nutrient levels were more important determinants of chlorophyll a concentrations. In summary, both land use and geology play a considerable role in influencing both macroinvertebrate community structure and periphyton biomass. The geological influence was mediated through direct effects on nutrient inputs into the stream (as measured by conductivity), as well as by the indirect influence upon stream water temperatures. The influence of land use on benthic communities is predominantly as a result of shade levels created by vegetation types and enrichment levels derived from agriculturally influenced land. These results are of particular importance when comparing or analysing results from studies involving different land use types, particularly when these land uses cover a range of altitudes or are found in more than one geological type
Colorimetric tolerances of various digital image displays
Visual experiments on four displays (two LCD, one CRT and hardcopy) were conducted to determine colorimetric tolerances of images systematically altered via three different transfer curves. The curves used were: Sigmoidal compression in L*, linear reduction in C*, and additive rotations in hab. More than 30 observers judged the detectability of these alterations on three pictorial images for each display. Standard probit analysis was then used to determine the detection thresholds for the alterations. It was found that the detection thresholds on LCD\u27s were similar or lower than for the CRT\u27s in this type of experiment. Summarizing pixel-by-pixel image differences using the 90th percentile color difference in E*ab was shown to be more consistent than similar measures in E94 and a prototype E2000. It was also shown that using the 90th percentile difference was more consistent than the average pixel wise difference. Furthermore, SCIELAB pre-filtering was shown to have little to no effect on the results of this experiment since only global color-changes were applied and no spatial alterations were used
The Sound of Adventure: Two Original Compositions That Combine Music, Sound Design, and Post-production, Inspired by Outdoor Experiences
Composers have been inspired by nature for centuries, but writing music about nature is becoming more popular in our day. Now, under titles like “Landscape Music” and “Environmental Music,” many composers seek to embody the feeling of nature in music. What has yet to be fully developed is how electronic music and landscape music can overlap in the chamber music world. This project culminates in two original compositions, Natural Opposition (ca. six min), and Giants at Night (ca. 15 min), that seek to satisfy the requirements of both realms by combining naturally inspired music with electronic influences. The compositions themselves contain principles of minimalism and spectralism, elctroacoustic music, impulse response and digital reverberation, and live manipulation of sound through post production techniques.
In this way, this project builds unity between the worlds of landscape chamber music and electronic music in new and intriguing ways
SURVEY OF AMPHIBIANS AND REPTILES IN POWHATAN COUNTY, VIRGINIA WITH SELECTED NATURAL HISTORY NOTES
This thesis establishes baseline data on the herpetofauna that exist in Powhatan county. No systematic study of the amphibians and reptiles in Powhatan county has ever been conducted. The methods used in this survey include hand capture, egg mass observations, road kill collections, and frog call surveys. Documentation of each species collected included measurements, photographs, range maps, and tape recordings.
This survey produced 8 species of salamanders, 11 anurans, 6 turtles, 4 lizards, and 14 snakes. Based on records in the Atlas of Amphibians and Reptiles of Virginia (Mitchell & Reay, 1999), 11 new county records were discovered. This brings county totals to 9 species of salamanders, 12 anurans, 6 turtles, 5 lizards, and 16 snakes.
Road kill surveys found that vehicular traffic kills at least 1 species of frog,1 species of salamander, 4 species of turtles, and 8 species of snakes. Bufo fowleri (Fowler\u27s toad) was the most commonly killed frog, Notophthalmus virtdescens viridescens (red-spotted newt) was the most commonly killed salamander, Terrapene caroljna carolina (eastern box turtle) and Kinosternon subrubrum subrubrum (common mud turtle) were tied in being the most commonly killed turtles, and Elaphe obsoleta obsoleta (black rat snake) was the most commonly killed snake.
Many sensitive areas of amphibian reproduction, such as the breeding sites for Gastrophryne carolinensis (eastern narrow-mouthed toad), Ambystoma opacum (marbled salamander), and Ambystoma macul atum (spotted salamanders), have been found and documented on range maps. Baseline information on the number of eggs per egg mass, and mortality rates have been established. Eighteen sites have been evaluated for relative abundance of frogs through late winter, spring, and summer
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A community-engaged infection prevention and control approach to Ebola.
The real missing link in Ebola control efforts to date may lie in the failure to apply core principles of health promotion: the early, active and sustained engagement of affected communities, their trusted leaders, networks and lay knowledge, to help inform what local control teams do, and how they may better do it, in partnership with communities. The predominant focus on viral transmission has inadvertently stigmatized and created fear-driven responses among affected individuals, families and communities. While rigorous adherence to standard infection prevention and control (IPC) precautions and safety standards for Ebola is critical, we may be more successful if we validate and combine local community knowledge and experiences with that of IPC medical teams. In an environment of trust, community partners can help us learn of modest adjustments that would not compromise safety but could improve community understanding of, and responses to, disease control protocol, so that it better reflects their 'community protocol' (local customs, beliefs, knowledge and practices) and concerns. Drawing on the experience of local experts in several African nations and of community-engaged health promotion leaders in the USA, Canada and WHO, we present an eight step model, from entering communities with cultural humility, though reciprocal learning and trust, multi-method communication, development of the joint protocol, to assessing progress and outcomes and building for sustainability. Using examples of changes that are culturally relevant yet maintain safety, we illustrate how often minor adjustments can help prevent and treat the most serious emerging infectious disease since HIV/AIDS
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