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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
261

The biology, distribution and control of ants in Hawaiian pineapple fields

Phillips, John January 1933 (has links)
Typescript. Thesis (Ph. D.)--University of Hawaii, 1933. Bibliography: leaves 261-301. UHM: HAWN also has reprint: Honolulu, HI : University of Hawaii at Manoa Library, 2000. c.3
262

Some Aspects of the Ecology of Lingula (Brachiopoda) in Kaneohe Bay, Hawaii

Worcester, William S 01 December 1969 (has links)
Lingula is one of the most morphologlcally conservative genera known. Thls brachiopod has remained essentially unmodified for 350-400 mllllon years (Hyman, 1959. Paine, 1963). It is one of the oldest, if not the oldest, llvlng animal genus wlth a fossil record, and is well represented in the geologic column from the Ordovician. Deposits containing Lingula are thought to have been formed in a shallow, warm, sea water environment (Weller, 1957, Cloud, 1948). Their fossil remains occur on all continents (except possibly Africa) in most kinds of sedimentary facies, but most frequently ln black-shales and related sediments (Moore, Lalioker and Fisher, 1952). [...] This investigation, which extended from June 1967 to February 1969, deals with the distribution, limiting factors, interspecific interactions, feeding, growth and other aspects of the life history of Lingula reevii in the southern sector of Kaneohe Bay. The main objectives were 1) to understand the ecological position of Lingula reevii, especially with respect to limiting factors, interspecific interactions, distributional pattern and growth and 2) to use this ecological information as an aid in the understanding of the ancient environments in which Lingula is found as a fossil. / Typescript. Bibliography: leaves 48-49.
263

Some Aspects of the Ecology of a Bivalve Mollusk in Kaneohe Bay, Oahu, Hawaii

Higgins, John H 01 June 1969 (has links)
Typescript. Bibliography: leaves 46-47.
264

Responses of Hawaiian Scleractinian Corals to Different Levels of Terrestrial and Carbonate Sediment

Te, Franklyn Tan 01 May 2001 (has links)
Goals of this investigation were: 1) Differentiate between the effects of turbidity and sedimentation on corals. 2) Differentiate the effects of carbonate and terrigenous sediments on coral growth and metabolism. 3) Develop a predictive model relating increased sediment loading to the photosynthetic rate, growth and survival of corals. 4) Evaluate the validity of the widely cited "10 mg cut-off point" and determine the levels of turbidity and sedimentation that are tolerated by corals. Earlier studies suggest that coral reefs decline when sediment loading levels exceed a sediment trapping rate of 10 mg cm-2 d-1 or a turbidity of 10 mg I-1. An integrated experimental design linked field and laboratory experiments. In the field, corals were transplanted to sites with varying levels of sedimentation. Turbidity, as linked to reduced light availability, had a significant affect on coral growth and metabolism in laboratory experiments but not coral growth or survival in field experiments. Turbidity in the field was highly variable and influenced greatly by wind velocity and rainfall. Terrigenous (or land-derived) sediments influenced light extinction more than carbonate (reef-derived) sediments. In laboratory experiments turbidity was more important than sediment trapping rate in affecting the photosynthetic ability and growth rates of corals. The predictive model stated that the lower the light level (as caused by increased turbidity) the lower the photosynthetic production of corals. The model was supported by results of laboratory experiments where conditions were precisely controlled and monitored. Under field conditions, the predictive model did not hold due to extreme natural variability in sediment loading and variation in a wide range of other environmental factors encountered at the experimental sites. Corals tolerated turbidity exceeding 120 mg I-1 and sediment trapping rates in excess of 11 mg cm2 d-1. Sediment loading is correlated with other environmental factors such as nutrient loading and reduced salinity. Composition of sediment varies widely between different locations. The "10 mg cutoff may prove to be useful in setting limits to vigorous coral reef development, although individual corals or coral assemblages may be able to survive and grow at levels exceeding this value. / Thesis (Ph. D.)--University of Hawaii at Manoa, 2001. Includes bibliographical references (leaves 235-264).
265

The role of Sagitta enflata in the southern Kaneohe Bay ecosystem

Szyper, James P 12 1900 (has links)
The chaetognath Sagitta enflata dominates the standing stock of macrozooplankton,and of planktonic carnivores, in the southern basin of Kaneohe Bay. During 1973-74, sampling with vertical net hauls showed no horizontal patchiness in the population. The abundance varied temporally, mainly over periods of months; shorter-term variations were similar to those expected between replicate hauls. Between 1968-69 and 1973-74, both the stock and the dominance of Sagitta in the community increased; both may be related to enrichment of the basin with sewage. Individual Sagitta eat an average of seven prey items per animal per day. The ration in terms of nitrogen or other weight measures varies with animal length, larger Sagitta ingesting more material each day, but smaller Sagitta ingesting a larger fraction of their own body weight daily. Sagitta's predation has little impact on the prey populations, other than Oikopleura, which is the main food of larger Sagitta. Sagitta excretes ammonium and phosphate at rates roughly similar to other zooplankton of similar size. When feeding is prevented during excretion experiments, the specific excretion rates decrease rapidly with time, approaching those observed in laboratory-starved animals. Like other zooplankton, Sagitta has higher N/P ratios in its body tissue than its prey; its soluble excreta thus have a still lower ratio. Despite its abundance and dominance of macroplankton stock, Sagitta is only a minor contributor to nutrient regeneration in the southern basin, which is to be expected, based on its trophic position. The population's rates of growth and mortality were considerably higher than the net change in the stock during most periods analyzed. The instantaneous rates of birth and death are strongly correlated, suggesting a feedback mechanism regulating the population. The population incorporates carbon at about 1% of the rate of primary production in the basin. This is consistent with ecological efficiencies of 10% at each of the two steps froln producers to herbivores to Sagitta's position as the dominant primary carnivore among the plankton. Most of Sagitta's production is probably consumed by predators in the southern basin. The major predator may be nehu, a fish taken for tuna bait from this and other nearby environments. With the planned diversion of sewage from the basin, it is likely that both the stock and the dominance of Sagitta in the southern basin will decrease. / Thesis for the degree of Master of Science (University of Hawaii at Manoa). Typescript. Bibliography: leaves 140-147.
266

Diel Changes in the Vertical Distributions of Some Common Fish Larvae in Southern Kaneohe Bay, Oahu, Hawaii

Watson, William 12 1900 (has links)
Nine series of vertically-stratified zooplankton tows were made with a closing net at a single station in southern Kaneohe Bay, Oahu, Hawaii, between 31 August 1973 and 11 April 1974. Sampling periods occupied from 12 to 26 hours, with tows usually taken at about 3 m intervals between the surface and a maximum depth of 10 m. A total of 21,254 fish larvae of 49 kinds was collected. Six species were abundant: Foa brachygrammus, Omobranchus elongatus, Callionymus decoratus, Caranx mate, Stolephorus purpureus, and Abudefduf abdominalis. Blennius sp. and Gnathanodon speciosus were commonly taken in small numbers. These common larvae displayed five "distribution patterns: 1. F. brachygrammus and the smallest S. purpureus were most abundant near the surface at night and at depths below 4 m during the day; 2. C. mate and G. speciosus were dispersed throughout the water column at night and usually most abundant between 5 m and 6 m depth during the day; 3. Blennius sp., o. elongatus, and A. abdominalis were dispersed throughout the water column at night and concentrated near the surface during the day; 4. the larger ~. purpureus maintained a level of maximum abundance below 6 m day and night; 5. C. decoratus was taken at all depths at all times. Patterns 1, 2, and 3 are shown to be light-related. Pattern 4 is shown to be partially attributable to avoidance of the towed net by S. purpureus larvae larger than about 6mm, and a feeding-related migration is proposed to account for pattern 5. The observed patterns are analogous to those shown for fish larvae in the open ocean on scales of from 50 m to 200 m. It is proposed that Kaneohe Bay represents a vertically compressed ocean with respect to the vertical distribution of fish larvae. / Typescript. Bibliography: leaves 130-134.
267

Distribution, Recruitment and Development of the Borer Community in Dead Coral on Shallow Hawaiian Reefs

White, Janet K. F. 12 1900 (has links)
Twenty-seven species of known or suspected coral skeletal borers were identified from shallow Hawaiian reefs. In comnarison to inventories of the borer communities collected from other tropical areas Hawaiian corals had an abundance of polychaetous annelids, fewer species of sipunculans,and acrothoracican barnacles, and far fewer boring sponges. Polychaetes were responsible for the majority of the bioerosion of dead coral in Kaneohe Bay, Oahu. Comparisons of living and dead sections of coral colonies indicated that the borer community was more diverse and abundant in areas of the skeletons lacking living tissue. Skeletal densities of three common coral species with branching growth form were found to influence the abundance of coral borers. The least dense skeletons had greater population densities of borers. It is suggested that these three species of corals can coexist in close proximity due, in part, to the development of varying abilities to withstand invasion by skeletal borers. In order to determine rates, si te preference and seasona.li.ty of settlement a series of settlement plates were cut from coral and placed in the field at ten sites in Kaneohe Bay, Oahu. Extrapolating from the surface area of the settlement plates, mean recruitment rates of coral borers were found to be 10,000 - 50,000 individuals m-2 month-1. The recruitment rates and species composition of epibiotic and borer faunas settling; on the dead coral plates differed dramatically between areas in Kaneohe Bay due to the effects of differences in physical and biological factors caused by sewage and slltation. The larvae of coral borers generally lacked clear seasonal settlement periods, suggesting that one or more mechanisms (e.g. continuous reproduction, long pelagic phase, etc.) functioned to assure the presence of larvae throughout the year. The ultimate cause for the development of such a strategy may be that the time and location of the production of suitable settlement sites on the reef surface is. unpredictable. Some of the larvae of both epibiotic and borer species exhibited settlement selectivity with respect to the position of the settlement surface. This finding indicates that the distribution of borers in coral skeletons might be due, in part, to active selection by the laryae for particular conditions. Development of the epibiotic and borer communities of dead coral was monitored using sequentially collected blocks cut from the coral Porites lobata. The abundance and species composition of these communities were found to differ between sites in Kaneohe Bay because of several biological and physical factors. In the south bay increased food supplies (in the form of plankton and plankton-derived detrital material). due to sewage enrichment, support extensive populations of filter and deposit-feeding invertebrates including coral borers. Sewage diversion did not appear to have had any dramatic effect on these communities by the end of the study period. In the north bay, where food availability is lower, fewer borers and epibiotic organisms were collected. The effects of fish grazing are considered to be another important factor determining the species composition and abundance of the coral borer community. Grazing fish were rare in south Kaneohe Bay during the study period, which may help to explain the abundance of sessile epifaunal species. In the north bay fish grazing is extensive and contributes to the growth of encrusting coralline algae on the test blocks and the benthos. Based on the results of the long term block study it was found that in Hawaii sessile filter-feeding invertebrates do not exclude coral borers from the substratum or inhibit their growth. In south Kaneohe Bay, where conditions caused increased abundances and growth rates of filter and depositfeeding invertebrates, bioerosion rates were accelerated. Encrusting coralline algae, which flourish on reefs exposed to fish grazing (eg. north Kaneohe Bay), inhibit settlement of borers and grow over burrow apertures, thus reducing the population of borers within the dead coral. Bioerosion rates of exposed, coralline algal covered, dead coral substrata are very low on pristine shallow Hawaiian reefs. / Bibliography: leaves 181-192.
268

Utilization of tropical pasture by beef cattle : the Cornell Net Carbohydrate and Protein System (CNCPS) and in situ mineral release in the rumen

Buck, Kevin January 2007 (has links)
Thesis (M.S.)--University of Hawaii at Manoa, 2007. / Includes bibliographical references (leaves 61-66). / vii, 66 leaves, bound ill. 29 cm
269

Photoecological strategies influencing the invasive success of the invasive marine macrophyte Eucheuma denticulatum on Hawaiian coral reefs

Dailer, Meghan L January 2006 (has links)
Thesis (M.S.)--University of Hawaii at Manoa, 2006. / Includes bibliographical references (leaves 91-96). / vi, 149 leaves, bound ill., map 29 cm
270

Toxicity of boron compounds in the Formosan subterranean termite, Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae)

Gentz, Margaret C January 2007 (has links)
Thesis (M.S.)--University of Hawaii at Manoa, 2007. / Includes bibliographical references (leaves 41-45). / v, 45 leaves, bound 29 cm

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