R-3 Repository :: Browsing by Author "Fisher, Frank M."

Browsing by Author "Fisher, Frank M."

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A paleoecological study of a one-hundred year sedimentary record of Galveston Bay, Texas
(1991) Yuill, Richard Matthew; Fisher, Frank M.
Paleoecological and geochemical methods were used to study changes in Galveston Bay for the period 1850-1988. The purpose of the study was to: (1) examine foraminiferal species distribution in space and time, (2) measure changes in sediment geochemistry, and (3) determine if human actions have measurably affected the distribution of foraminifera. During 1987-1988, gravity cores were collected, examined by x-radiography for evidence of disturbance, and subsampled at various depths. Sediment accumulation rates were determined by lead-210 analysis. Subsamples were analyzed for particle size, TOC, foraminifera, and selected chemical elements including Al, Ba, Ca, Cd, Cr, Cu, Fe, Mg, Na, Ni, Sn, Sr, V, and Zn. Foraminifera were identified to species and enumerated as percent relative abundance. Barium concentration was depth-dependent for a number of cores. A regression of year before present against Log10 of barium was used to establish the chronology of additional cores. There were two significant geochemical trends: (1) a high correlation of the metals, including Al, Cr, Cu, Fe, Mg, Na, and V, to percent silt and clay, and (2) high intercorrelations between metals, especially to Al and Fe. Barium was poorly correlated to percent silt and clay and to metals. Thus, adsorption onto silt and clay particles and co-precipitation of metals with iron and aluminum hydrous oxides are apparently two of the dominant processes controlling the fate of metals in Galveston Bay. Dominant foraminifera in Galveston Bay were Miliammina fusca, Ammotium salsum, Ammonia parkinsoniana, and Elphidium spp. The species composition of individual subsamples generally fit into one of two biofacies described for Gulf of Mexico estuaries: (1) the Miliammina-Ammotium biofacies, generally confined to low salinity and (2) the Ammonia-Elphidium biofacies, dominant in the middle and lower estuary. Results showed a temporal shift from Miliammina-Ammotium to the Ammonia-Elphidium. These shifts occurred in the late 1800s in lower and middle Galveston Bay and as recently as the 1970s in Trinity Bay. This stepwise progression of a high-salinity biofacies further into the estuary coincides with dredging in the Houston Ship Channel. The pattern and timing of the species shift supports the hypothesis that dredging of the Houston Ship Channel has been a major contributing factor to salinity intrusion in Galveston Bay.
A study on methane emission from rice paddy fields and the nonstructural carbohydrates in rice plants
(1993) Wang, Yongbing; Sass, Ronald L.; Fisher, Frank M.
A dynamic process of the nonstructural carbohydrate translocation in rice plants is presented based on observation during one growing season. Differing amounts of nonstructural carbohydrates might be lost through rice plants due to the experimental plant manipulation. Relative to the CH$\sb4$ flux from the area of normal plants, significant increases in methane emission were observed in the area of manipulated plants. It is proposed that due to the experimental plant manipulation, more organic deposition entered the soil through rice plants than that under normal condition and, the lost nonstructural carbohydrate resulted in methane emission through the anaerobic methanogenesis in the rice field.
Amino acid transport in Trypanosome gambiense
(1974) Hansen, Brian David; Fisher, Frank M.; Read, Clark P.
Using C-labeled amino acids, absorption of L-lysine, L-arginine, L-glutamate, L-phenylalanine, L-methionine, L-threonine, L-alanine, and L-glycine were studied. All amino acids appeared to be absorbed by both simple diffusion and mediated systems. Inhibitions produced by analogues indicate 5 possible transport loci. Locus A may have 3 Bites, one which transports lysine and the remaining 2 binding glutamate and arginine. When occupied, the latter 2 appear to stimulate the transport of lysine. Methionine and phenylalanine were shown to bind nonproductively at the lysine transport site. Locus B transports threonine, glycine, and alanine with negligible interaction with the other amino acids studied. This locus is partially Na+-sensitive. Locus C transports glutamate primarily. Locus D has 2 transport sites, one for phenylalanine and one for methionine. Threonine shows slight interaction at this site. Locus E also has 2 transport sites, one for lysine and one for arginine. All 8 amino acids were tested for Na+ sensitivity, with only the amino acids entering at Locus B affected. Further evidence for Na+ sensitivity of Locus B was demonstrated in that the uptake of threonine, glycine, and alanine was ouabain-sensitive. The uptake of methionine and phenylalanine was measured in the presence of an amino acid mixture and the observed values agreed with those predicted by calculation according to the technique of Read et al. (1963).
Edaphic and pyric influences on two contiguous savannas of East Texas
(1979) Streng, Donna Rae; Harcombe, P. A.; Fisher, Frank M.; Ward, C. H.
Vegetation, soil, history (land use and tree age), site favorability (tree growth rates), and flammability were examined in four contiguous East Texas communities, two of which are savannas. The data suggest that woody plant densities are edaphically limited on one of the savannas (sedge meadows), and fire limited on the other savanna (pine-bluestem savanna). The edaphic savanna (meadows) has acidic soil with a shallow claypan, and these features are apparently responsible for its distinctive vegetation, low sapling densities, and slow tree growth rates. The soil characteristics (profile, texture, pH) and the tree composition of the fire savanna are similar to a neighboring forested upland. It is inferred that fire has reduced tree density since tree growth rate and sapling densities are higher than in the forest, and it appears that logging was not responsible for low tree densities. Furthermore age histograms from this savanna reveal low hardwood recruitment from 1953-196. 1955-1956 was a period of drought in East Texas and age structures from all communities examined have a noticeable gap during this period with the savanna's being more extensive. This age gap suggests that drought reduces tree recruitment (increases mortality) and in some communities this reduction is further accentuated by fire. Also, since both savannas are more flammable than the wooded areas (as measured by Rothermel's (1972) model of fire spread) they probably bum more frequently. Thus, they are maintained by a positive feedback cycle -- i.e. burning increases flammability by favoring herbs which increases the probability of a recurring fire. On the other hand, one of the wooded communities (west side) was a former savanna (as revealed by aerial photographs), which through chance or the intervention of man has remained fire-free long enough to develop a densely packed, nonflammable fuel bed. The present nonflammability of this community suggests that it may have effectively escaped from the influence of fire.
Effects of age on toxicity to freshwater algae of water soluble extracts of No. 2 fuel oil
(1979) Hsieh, Ying-Ping; Ward, C. H.; Fisher, Frank M.; Tomson, Mason B.
The effects of fresh-prepared, 4-day-aged and 8-dayaged Ho. 2 fuel oil water soluble fractions on the growth of Selenastrum capricornutum were investigated. The freshprepared water soluble fraction inhibits both the growth rate and cell yield of S. capricornutum. Its toxicity decreases after four days but there is still residual toxicity. This residual toxicity decreases very slowly; the effects of the 8day-aged water soluble fraction on S. capricornutum are comparable with those of the 4-day-aged one. The components of the water soluble fractions were identified by a mass spectrometer interfaced to a gas chromatograph. The major components are aromatic compounds, of which, the benzene and indene derivatives volatilize '.very quickly. Naphthalene and methyl naphthalenes volatilize in four days. However, the di-aromatic and tri-aromatic compounds, having boiling points higher than naphthalene,are still in the medium after 8 days. Sixteen component compounds were chosen for chemical analysis and toxicity testing. The concentrations of these compounds in the fresh-prepared , 4-day-aged and 8-day-aged water soluble fractions were determined, and their toxicities were investigated by "algal lavra" technique. The concentration distribution test on the agarized medium shows that the concentrations of naphthalene and phenanthrene are comparable at a selected distance after diffusing in the medium for four days. The results indicate that methyl, dimethyl and trimethyl naphthalenes are more toxic than naphthalene. The most toxic compounds are dibenzofuran, fluorene, phenanthrene and dibenzothiophene, v/hich have high boiling points.
Growth rate, tree form and bark texture of Quercus falcata Michx. and Q. falcata variety pagodaefolia E11. in four stands in Southern East Texas
(1979) Glitzenstein, Jeff Steven; Harcombe, P. A.; Ward, C. H.; Fisher, Frank M.
Quercus falcata Michx. growth rate, importance (basal area), tree form, and bark texture were examined over a local gradient in soil moisture (as inferred from site vegetation, slope position and soil texture) . At drier sites, growth rate was found to be slower, bark was found to be rougher, and the maximum tree height was found to be smaller. Quercus falcata basal area also differed greatly between study sites. However, contrary to expectation, changes in basal area did not parallel changes in diameter growth rate, suggesting the possible importance of historical factors in determining the distribution of this species. The frequency of occurrence of the two varieties of Quercus falcata, variety falcata and Q. falcata var. pagodaefblia Ell., was compared among the four study sites, and within one study site. As was found by Caplenor et al. (1968), variety falcata reaches its maximum abundance under drier conditions, while variety pagodaefolia is most abundant in moister environments.
Lead in Texas wetlands and its relationship to waterfowl hunting
(1975) Price, Linda Havighurst; Fisher, Frank M.
Lead shot deposited in wetland ponds by waterfowl hunters over a number of years may be a significant source of lead in localized areas in this environment. To determine whether such shot contributes to the overall lead content of marshes, samples of soils, plants, fishes, crustaceans and ducks were collected in Chambers County, Texas, for lead analysis. Soil from sites near a waterfowl blind in a heavily hunted pond had significantly more extractable lead than soil collected in the same pond out of shotgun range of the blind; however, no differences in lead, attributable to spent shot, were noted between three ponds which had experienced different hunting pressures over the past ten years. Rather, the amount of lead in sections of core samples from the three ponds (mean of 66 ppm, dry wt) was related to clay content of the soils and was high compared to the average amount of lead reported in soils throughout the world. The level of lead, did not diminish down to 7 cm in two of the ponds examined. From the increase in extractable lead, noted 75 days after seeding pond soil with varying amounts of shot, a release rate of extractable lead from shot was calculated. The amount of lead found in plant tissue was correlated with the lead in the soil from which the plant was collected. More lead was found in plant roots than plant stems and blades. Mean amounts of lead in Eleocharis parvula (17.3 ppm), Paspalum virgatum (7.5 ppm) and the overall levels of lead in fishes (19.9 ppm) and crustaceans (37.6 ppm) were much higher than previously reported for such organisms. The mean amount of lead in ducks analyzed (5.7 ppm) was slightly above that reported for waterfowl in other surveys and 5$ of the ducks collected during hunting season had levels of lead characteristic of birds suffering from lead-poisoning.
Responses of Littorina irrorata to temperature and salinity variations
(1967) Wehking, Beverly Jane; Fisher, Frank M.
Experiments were conducted to determine the survivability of Littorina irrorata and L. lineolata under various conditions of water temperature and salinity, and to determine the sodium and potassium ion concentrations in the haemolymph of L. irrorata under various conditions of water temperature and salinity. The vertical movements of L. irrorata in the field and under laboratory conditions were studied. It was found that L. lineolata survived heat better than L. irrorata, but L. irrorata survived cold better than L. lineolata. L. lineolata survived the higher salinities better than L. irrorata. L. irrorata was more resistant to desiccation than was L. lineolata. The low salinities (0°/oo, 5°/oo) placed more stress on both species than did the highest salinity (40°/oo). These observations were related to the ecologies of the animals. L. irrorata was found to maintain sodium and potassium ions in the blood at higher concentrations than those in the surrounding water, at all temperatures. This apparent control was not due to the method of blood extraction, to inaccuracies in glassware calibration, or to lack of contact with the medium. However, the control appeared to depend in part on the ability to retract into the shell from time to time. Temperature extremes (0°C., 42.5°C.) did decrease the snail's ability to maintain the difference in Na+ and K+ concentrations. The vertical movements of L. irrorata in nature correspond with the tidal movements. The cue for the snails' movements is unknown. The movements are not cued by humidity variations, time alone (inherent rhythm), the direct effects of sun and moon, or immersion and exposure. It is suspected that the vascular characteristics of the marsh grass on which L. irrorata lives are the cue for the snails' movements.
Responses of the false limpet, Siphonaria pectinata (Gastropoda, Pulmonata) to osmotic stress
(1967) McAlister, Robert Otis; Fisher, Frank M.
Investigations were conducted on the littoral euryhaline molluso Siphonaria pectinata Linnaeus which inhabits the granite jetties near Galveston, Texas, Animals were subjected to a wide range of salinities, and the [delta-t-f] and sodium concentrations of the body fluids were measured under conditions of osmotic stress. Experiments were designed to investigate the possibility of some control mechanism being operative to explain this animalls tolerance to osmotic stress. Experimental evidenoe Is presented that fluctuations in the osmotic oonoentrations of the body fluids are largely due tp water movements. Evidence is further presented that fluotuations In the osmotio concentration,of the hemolymph may be effeotively reduced during stress for periods of up to 48 hours. This is done by physical exertion on the part of the animal, resulting in a tight binding of the mantle fringe and outer margin on the shell to the substrate. Such exertion effectively results in greatly reduced exposure of the soft parts of the animal to the stress environment. The end result is a resistance to swelling or shrinking in hypoosmotio and hyperosmotio situations. respectively. The results suggest that dessication in air and expo-sure to hypersmotic salinities of water yield similar end results in terms of deleterious effects on the body fluid concentration of the animal. A discussion is presented of the possible significance of the fact that the animals seem more tolerant to hyperosmotic than to hypoosmotic conditions. The significance of the animal's apparent mechanical osmoregulatory ability is also discussed.
The response of wetlands to sea level rise: Ecologic, paleoecologic, and taphonomic models
(1994) Hoge, Bradley Earle; Fisher, Frank M.
Texas coastal wetlands will be increasingly endangered over the coming century as sea level rises due to global warming. Since estimates of sea-level rise may be similar to trends interpreted from Holocene sediments, a paleoecologic analysis of wetland peats may provide a predictive model for wetland succession. Three areas of focus are necessary to achieve predictive power, however: ecologic, sedimentalogic, and taphonomic. No single microtaxonomic group is well preserved in all depositional environments. Foraminiferal assemblages delineate salt to brackish marsh environments, but are absent in fresh marsh sediments. Ostracodes and diatoms occur in all marsh types, but ostracodes are sporadically preserved and diatom thanatocoenoses from different environments become too similar to significantly indicate different biocoenoses. A combined thanatocoenosis composed of microtaxa with similar ecological requirements but different taphonomic signatures provides an effective method of identifying sea-level history from wetland sediment cores, however, since taphonomic effects on selected groups overlap. Calcium carbonate and silicate dissolve according to pH, while proteinaceous cements of many agglutinated foraminifera withstand dissolution and are removed only through oxidation-reduction reactions. An analysis of these trends in the Galveston Bay system supports the following taphonomic model: During accretionary still stands, in-situ preservation is high for each thanatocoenosis. This is due to the effects of time averaging over an otherwise harsh and patchy chemical environment. During rapid sea-level rise, fresh marsh sediments become inundated with brackish to salt water. This tends to raise the pH and Eh, enhancing preservation. The thanatocoenoses grade sharply from mixed to distinct. During flooding, or progradation, fresh water inundates brackish to salt water sediments. This tends to lower pH and Eh, decreasing preservation. In situ thanatocoenoses are reduced to only a few species or eliminated completely. This taphonomic model suggests that the traditional approach of using a single microfossil group to interpret sea-level trends may be inadequate. The combined thanatocoenosis approach can produce better controls on paleoecologic and paleoclimatic interpretations, and will allow for better predictions of future trends.

Browsing by Author "Fisher, Frank M."

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