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Articles 3271 - 3300 of 3959

Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

The Temporal And Spatial Distribution Of Blue Crab Larvae On The Mid-Atlantic Bight Adjacent To The Chesapeake Bay, 1982-1983, Lyle Michael Varnell Jul 1989

The Temporal And Spatial Distribution Of Blue Crab Larvae On The Mid-Atlantic Bight Adjacent To The Chesapeake Bay, 1982-1983, Lyle Michael Varnell

OES Theses and Dissertations

Recruitment processes are important information for the management of commercially and recreationally exploited marine species. Recruitment processes of the Chesapeake Bay's most important commercial and recreational species, the blue crab, are unknown, due in part to the lack of knowledge of the processes directly preceeding recruitment.

The present study was undertaken to investigate and explain the movement and developmental patterns of blue crab larvae while offshore. Interannual and intraseasonal variations of these patterns were also examined.

Sampling occurred from May to November during 1982 and 1983. Larvae were collected at three depths (neuston layer (upper 10 cm), one meter and …


Picoplankton/Phytoplankton Dynamics In Hampton Roads, Virginia, Leslie E. Dorworth Jul 1989

Picoplankton/Phytoplankton Dynamics In Hampton Roads, Virginia, Leslie E. Dorworth

OES Theses and Dissertations

The biomass distribution of the three main size components of the phytoplankton (net, nano, and picoplankton) was examined in the lower Chesapeake Bay. Work was done at two stations during the spring and neap tidal cycles when freshwater flow into the bay was at its seasonal minimum and maximum. Emphasis was placed on how the picoplankton ( < 2.0 μm, > 0.2 μm) reacted during the sampling period.

Picoplankton made up approximately 13% of the total biomass, during the observed time period, at the more oceanic station. The picoplankton fraction contributed up to 16% of the total biomass at the estuarine station. From this …


The Remipedia (Crustacea): A Study Of Their Reproduction And Ecology, Jill Yager Jul 1989

The Remipedia (Crustacea): A Study Of Their Reproduction And Ecology, Jill Yager

Biological Sciences Theses & Dissertations

Remipedes are an unusual group of troglobitic crustaceans that live exclusively in anchialine caves. Since their discovery in 1979, nine species have been described, seven of which are found in caves in the West Indies, one from the Yucatan peninsula of Mexico and one from the Canary Islands. Most of what is known about these animals has come mainly from taxonomic descriptions. Little has been published about their reproductive biology or ecology. The objectives of this dissertation were to investigate the reproductive biology and ecology of the remipedes inhabiting Sagittarius Cave on Grand Bahama Island, Bahamas.

Sagittarius Cave was chosen …


Temporal And Spatial Patterns Of Abundance Of Age 0 Threadfin Shad (Dorosoma Petenense) In Overton Arm, Lake Mead, William Lee Pelle Jun 1989

Temporal And Spatial Patterns Of Abundance Of Age 0 Threadfin Shad (Dorosoma Petenense) In Overton Arm, Lake Mead, William Lee Pelle

Publications (WR)

Temporal and spatial patterns of age 0 threadfin shad (Dorosoma petenense) abundance and growth, in the Overton Arm of Lake Mead, were examined to evaluate the effects of resource availability on the young fish. This was part of a larger, game fishery enhancement study (Lake Mead Fertilization Project), designed to assess feasability of increasing survivorship of larval/juvenile shad by boosting phosphate levels, thereby increasing algal and zooplankton biomass, during the shad spawning period. Shad are the primary forage base for the striped bass (Morone saxatilis) and black bass (Macropterus salmoides) fisheries. Weekly samples were …


Limnological Monitoring Data For Lake Mead During 1988, Suzanne E. Leavitt, Larry J. Paulson, State Of Nevada: Division Of Environmental Protection Apr 1989

Limnological Monitoring Data For Lake Mead During 1988, Suzanne E. Leavitt, Larry J. Paulson, State Of Nevada: Division Of Environmental Protection

Publications (WR)

Limnological monitoring was conducted in Las Vegas Bay and Boulder Basin from April to December of 1988. The purpose of the monitoring was to (i) document possible changes in water quality resulting from decreased phosphorus loading and increased ammonia in Las Vegas Wash, and (ii) establish a data base for evaluating the adequacy of water quality standards.


Population Variation In The Mitochondrial-Dna Of Two Marine Organisms: The Hard Shell Clam Mercenaria Spp. And The Killifish, Fundulus Heteroclitus, Bonnie Lynn Brown Apr 1989

Population Variation In The Mitochondrial-Dna Of Two Marine Organisms: The Hard Shell Clam Mercenaria Spp. And The Killifish, Fundulus Heteroclitus, Bonnie Lynn Brown

OES Theses and Dissertations

The two major topics are covered in this dissertation: the integration of molecular genetic tools with applied aquacultural research and short-term evolutionary dynamics. The first study investigated the extent of geographic differentiation of native clam stocks along the U.S. east and Gulf coasts. Clam mitochondrial DNA (mtDNA) demonstrated size polymorphism (16.5-19.0 kb) and restriction site heteroplasmy. Size heteroplasmic individuals occurred at a frequencies of 0-89% in clam populations. Restriction site heteroplasmy occurred in 12% of the 317 individuals assayed. Results of the study indicated that although harbouring a wealth of genetic variation, clams from northern regions were similar and lacked …


Red Swamp Crayfish Ecology In Lake Mead, Suzanne E. Leavitt, Jennifer Stephens Haley, Mikell Hager, Donald H. Baepler, Nevada Department Of Wildlife Mar 1989

Red Swamp Crayfish Ecology In Lake Mead, Suzanne E. Leavitt, Jennifer Stephens Haley, Mikell Hager, Donald H. Baepler, Nevada Department Of Wildlife

Publications (WR)

Red swamp crayfish (Procambarus clarkii) were trapped in Flamingo Wash, an urban wash of Las Vegas, during four periods of 1988. Life history and reproductive success were determined. The trapped crayfish were marked and released into a study cove in Lake Mead as part of an experimental stocking program. Retrap data from the study cove were used to determine life history, habitat preferences, and movement patterns of the stocked crayfish. In addition, a literature search was done on red swamp crayfish ecology, including food preferences, life history, habitat preferences and fish predation.


Formulation Of A Management Scheme For The Swordfish Fishery Of The Eastern Caribbean, Harold F. Upton Jan 1989

Formulation Of A Management Scheme For The Swordfish Fishery Of The Eastern Caribbean, Harold F. Upton

Marine Affairs Theses and Major Papers

During the 1983 season, two U.S. longline vessels initiated the first attempts at the commercial exploitation of swordfish in the Eastern Caribbean. In 1986, the number of U.S. vessels participating in the fishery surpassed 40 with landings of nearly two million pounds per season. The sudden influx of participants and technology to the region has resulted in a variety of user conflicts and associated policy issues. Major areas of concern involve the conservation of a heavily exploited resource and the distribution of benefits which accrue from resource exploitation among the resource-adjacent island states and U.S. fishing operations. This study examines …


Socioeconomic Aspects Of Small-Scale Commercial Fisheries Development In The Republic Of The Marshall Islands, Cheryl Ann Mandich Jan 1989

Socioeconomic Aspects Of Small-Scale Commercial Fisheries Development In The Republic Of The Marshall Islands, Cheryl Ann Mandich

Marine Affairs Theses and Major Papers

This study examines the sociocultural aspects of fishery development in the Republic of the Marshall Islands. It is based upon field research conducted through interviews with indigenous fisherfolk, business people, and expatriates. The Marshall Islands were selected because they have a limited economic base, yet have abundant fishery resources which have considerable potential to generate foreign exchange. Many studies focus on the technical aspects of fishery resource development. However, none address the sociocultural factors that influence its success. This thesis demonstrates that several aspects of Marshallese fishing society, some of which correspond to characteristics of the peasantry identified by Rogers …


Antarctic Peninsula Mysticete Whales: Conservation And Research, Gregory Schofield Stone Jan 1989

Antarctic Peninsula Mysticete Whales: Conservation And Research, Gregory Schofield Stone

Marine Affairs Theses and Major Papers

This paper reports original research from two recent studies in the Antarctic Peninsula area, reviews past sighting information and policies affecting mysticete whales, and recommends future research. Due to poor management by the International Whaling Commission, mysticete whales are among the most severely depleted species groups in the Antarctic. The combined total Antarctic harvest from 1920 to 19867 for blue Balaenoptera musculus, fin B. physalus, sei B. borealis, minke B. acutorostrata and humpback Megaptera novaeangliae whales was over one million animals. The effect of this hunting pressure is the dominant factor determing the present status of Antarctic …


Medic Variety Evaluation., C. K. Revell Jan 1989

Medic Variety Evaluation., C. K. Revell

Experimental Summaries - Plant Research

Trial 89M57

Medic variety evaluation - rows.
Merredin Research Station (Paddock T5)

Trial 89ME71

Selection of early maturing M. murex.
Nokaning.

Trial 88ME86

Evaluation of Santiago in low rainfall areas.
Mukinbudin.

Trial 87M73

Medic variety evaluation - large plots.
Merredin Research Station.

Trial 86M65

M. polymorpha variety evaluation - large plots.
Merredin Research Station.

Trial 88ME84

Evaluation of burr medics on Morrel soils.
Nokaning.

Trial 88SC30

Selection of early maturing M. murex.
Merredin.


Water Relations Of Obligate Riparian Plants As A Function Of Streamflow Diversion On The Bishop Creek Watershed, S. D. Smith, J. L. Nachlinger, A. B. Wellington, C. A. Fox Jan 1989

Water Relations Of Obligate Riparian Plants As A Function Of Streamflow Diversion On The Bishop Creek Watershed, S. D. Smith, J. L. Nachlinger, A. B. Wellington, C. A. Fox

Life Sciences Faculty Research

We investigated the water relations of obli-gate riparian plants on paired diverted and undiverted reaches on Bishop Creek, Eastern Sierra Nevada. Ri-parian plants on diverted reaches had reduced stomatal conductance and water potential compared to plants on undiverted reaches in a dry year, but not in a high runoff year. Juvenile plants on diverted reaches had reduced stomatal conductance and lower midday water potentials relative to surrounding mature trees, a trend that was not observed on undiverted reaches. Plants on diverted reaches possessed significantly smaller, thicker leaves and a reduced total leaf area relative to trees on streamside reaches. Reduced …


Riparian Plant Water Relations Along The North Fork Of The Kings River, California, J. L. Nachlinger, S. D. Smith, R. J. Risser Jan 1989

Riparian Plant Water Relations Along The North Fork Of The Kings River, California, J. L. Nachlinger, S. D. Smith, R. J. Risser

Life Sciences Faculty Research

Plant water relations of five obligate ripar-ian species were studied along California's North Fork Kings River. Diurnal stomatal conductance, transpi-ration, and xylem pressure potentials were measured throughout the 1986 growing season and in mid-season in 1987. Patterns were similar for all species although absolute values varied considerably. Maximum stomatal conductance occurred early in the day and season during favorable environmental conditions and decreased as air temperature and the vapor pressure difference between the leaf and air increased. Maximum transpiration rates occurred in mid-morning and mid-summer resulting in estimated daily water losses per unit sunlit leaf area of 163-328 mol H2O …


An Isotopic Analysis Of The Hydrology And Riparian Vegetation Water Sources On Bishop Creek, M. L. Space, J. W. Hess, S. D. Smith Jan 1989

An Isotopic Analysis Of The Hydrology And Riparian Vegetation Water Sources On Bishop Creek, M. L. Space, J. W. Hess, S. D. Smith

Life Sciences Faculty Research

Five power generation plants along an eleven kilometer stretch divert Bishop Creek water for hydro-electric power. Stream diversion may be adversely affecting the riparian vegetation. Stable isotopic analysis is employed to determine surface water/ground-water interactions along the creek. surface water originates primarily from three headwater lakes. Discharge into Bishop Creek below the headwaters is primarily derived from ground water. The average δD and δ18O values are significantly different for surface water and ground water that an isotopic analysis can delineate between these two components of flow. Therefore isotopic shifts along the creek can determine gaining reaches. In addition, by knowing …


Perceptions Of The Texas State And Federal Closures Among Inshore Shrimpers In Galveston Bay, Texas And Calcasieu Lake, Louisiana, Nina H. Garfield Jan 1989

Perceptions Of The Texas State And Federal Closures Among Inshore Shrimpers In Galveston Bay, Texas And Calcasieu Lake, Louisiana, Nina H. Garfield

Marine Affairs Theses and Major Papers

The inshore shrimp fisheries along the coast of the Gulf of Mexico represent a significant portion of the total shrimp harvest in the Gulf. The shrimp harvest is allocated to the offshore and inshore fisheries through the use of season closures. In 1981, the Gulf of Mexico Regional Fisheries Management Council began implementing a policy known as the Texas Closure; a seasonal closure of the waters of the Federal Conservation Zone concurrent with the traditional season closure of the state waters of Texas. One impact of the Texas Closure on the offshore fishery has been fleet displacement from Texas to …


Maine Nonpoint Source Pollution Assessment Report, Bureau Of Water Quality Control Jan 1989

Maine Nonpoint Source Pollution Assessment Report, Bureau Of Water Quality Control

Maine Collection

Maine Nonpoint Source Pollution Assessment Report

Prepared by the Maine Department of Environmental Protection, Bureau of Water Quality Control, Augusta, Maine 1989.

Contents: Executive Summary / Introduction / Methodology / Statewide Water Quality Summary / State And Local Agency Programs for Control of Nonpoint Source Pollution / Process for Identification of Best Management Practices and Associated Standards / List of References / List of Figures / List of Tables



Systems For Early Sowing Of Wheat In Low Rainfall Zones., N J. Kerr Jan 1989

Systems For Early Sowing Of Wheat In Low Rainfall Zones., N J. Kerr

Experimental Summaries - Plant Research

Background and early significance. Effect of sowing date and nitrogen fertilizer on wheat varieties in low rainfall areas, 89GE76, 89GE77, 89NM1, 89GE78, 89NM2, 89NM3, 89GE78. Tillage and sowing methods for early sowing of wheat in low rainfall areas, 89GE79. Aims, Background, Experimental details.


Tactical Nitrogen Decisions For Wheat (And N Rates Trials), J. W. Bowden, R. J. Lunt Jan 1989

Tactical Nitrogen Decisions For Wheat (And N Rates Trials), J. W. Bowden, R. J. Lunt

Experimental Summaries - Plant Research

Trial 89NO77 (89NO76)

Location: Grass Valley.

History: 1984 Lupins.

1985/86 pasture legumes and about 100 kg super/ha.

1987 Wheat yield of 2.8 t/ha using 45 kg DAP/ha and 60 of urea 2-4 WAS.

1988 Gungurru lupins (27 kg/ha seed) yielding 1.9 t/ha using 80 kg super/ha.

Tactical nitrogen trials - summary of treatments required.

Trial 89NO77

Location: Meckering

Treatments existed of nitrogen and urea. Nitrogen was not applied at seeding. Urea was applied at seeding.

Trial 88No77

Tactical nitrogen trials. - summary of observations.

Location: Grass Valley.

Trial 89NO76

Hand harvest 23/11/1989.
Yield components for copper sufficient plots reps. I …


Fall 1989, Nsu Oceanographic Center Jan 1989

Fall 1989, Nsu Oceanographic Center

Currents

No abstract provided.


Summer 1989, Nsu Oceanographic Center Jan 1989

Summer 1989, Nsu Oceanographic Center

Currents

No abstract provided.


Winter 1989, Nsu Oceanographic Center Jan 1989

Winter 1989, Nsu Oceanographic Center

Currents

No abstract provided.


Spring 1989, Nsu Oceanographic Center Jan 1989

Spring 1989, Nsu Oceanographic Center

Currents

No abstract provided.


Gammaropsis Arawakia, A New Species Of Marine Amphipoda (Crustacea) From Jamaica, James Darwin Thomas, J. L. Barnard Jan 1989

Gammaropsis Arawakia, A New Species Of Marine Amphipoda (Crustacea) From Jamaica, James Darwin Thomas, J. L. Barnard

Marine & Environmental Sciences Faculty Articles

One of the dominant amphipods in algal turf communities at Discovery Bay, Jamaica, is a new species, Gammaropsis arawakia, characterized by long peduncle of uropod 3, small coxa I, 3-articulate accessory flagellum, extremely setose gnathopod 2, one pair of dorsal teeth on urosomite I, pointed ocular lobe, and oblique upper margin of cephalic sinus for antenna 2.


Four Species Of Synopiidae From The Caribbean Region (Crustacea: Amphipoda), J. L. Barnard, James Darwin Thomas Jan 1989

Four Species Of Synopiidae From The Caribbean Region (Crustacea: Amphipoda), J. L. Barnard, James Darwin Thomas

Marine & Environmental Sciences Faculty Articles

Synopia ultramarina is redescribed from the Gulf Stream and the Florida Keys and comments are made on the tangled taxonomy in Synopia. Tiron bellairsi, originally described from Barbados, is reported from Belize, at the opposite side of the Caribbean Basin. Garosyrrhoe bigarra, a Pacific species, is also reported from Belize, but no clear subspecific differences are detected as yet between Pacific and Atlantic populations.


A New Species, Ampelisca Burkei, (Crustacea, Amphipoda) From Florida, J. L. Barnard, James Darwin Thomas Jan 1989

A New Species, Ampelisca Burkei, (Crustacea, Amphipoda) From Florida, J. L. Barnard, James Darwin Thomas

Marine & Environmental Sciences Faculty Articles

A new species Ampelisca burkei, from Florida, is described. This species appears to be very close to A. lobata Holmes, from the eastern Pacific Ocean, but differs in the shape and setation of article 4 on pereopod 7, and the presence of an anteroventral spine-seta on article 5 of pereopod 7.


Pasture Agronomy., C. K. Revell Jan 1989

Pasture Agronomy., C. K. Revell

Experimental Summaries - Plant Research

Trial 89ME82

a. Medic establishment.

Establishing burr medic pastures with cereal cover.
Merredin

Trial 89SC19

b. Serradella - Potash response.

Response of serradella to potash fertilizer.
South Carrabin

Trial 89M44

c. Serradella/Grass competition

Effect of grass competition on production of serradella.
Merredin Research Station.

Trial 89SC HERB

d. Herbicide tolerance of Serradella.

Herbicide tolerance of Madeira serradella.
South Carrabin


New Block Badgingarra Rs Late Time Of Seeding., J. W. Bowden, R. J. Lunt Jan 1989

New Block Badgingarra Rs Late Time Of Seeding., J. W. Bowden, R. J. Lunt

Experimental Summaries - Plant Research

Trial 89BA33,

Location: Badgingarra

Based on a 1.5 t/ha potential yield, the strategic treatment was planned to be 120 kg urea/ha 4WAS. However, the crop was poorly established and so NH4NO3 was used in the hope of getting better tillering than would be possible with the slower release urea source. Gambling on equal dollars to urea for 2/3 N, but believe that twice as effective.

DAP was used to place nitrogen with the seed in case there was no rain of significance after seeding. This nitrogen (only 5 kg/ha) was probably lost with the rains of 20-28/7/89 (50 mm). Urea …


Tactical Nitrogen Decisions For Wheat (And Nitrogen Sources Rates And Times On Wheat), J. W. Bowden, R. J. Lunt Jan 1989

Tactical Nitrogen Decisions For Wheat (And Nitrogen Sources Rates And Times On Wheat), J. W. Bowden, R. J. Lunt

Experimental Summaries - Plant Research

Trial 89MO49

Location: Tenderloin, Brand Highway, Regan's Ford.

History:

1987 Aroona wheat with 70 kg DAP and 3 kg CuSO4 at seeding followed by 60 urea at 3WAS and another 40 urea at 6WAS. Yield was about 1.7 to 1.8 t/ha;
1988 Gungurru lupins with 120 kg super and manganese/ha yielded 1.9 t/ha. 350-400 ml Roundup/ha and one cultivation prior to seeding.


Factors Affecting Lupin Crop Establishment In The Northern Agricultural Region Of Western Australia., K W. Mccarthy, A M. Doswell, R J. Delane, M W. Sweetingham Jan 1989

Factors Affecting Lupin Crop Establishment In The Northern Agricultural Region Of Western Australia., K W. Mccarthy, A M. Doswell, R J. Delane, M W. Sweetingham

Experimental Summaries - Plant Research

Lupin establishment, 89EC6. The effect of machine, depth of sowing, seed soil contact and herbicide incorporation on lupin establishment, 89GE8. The effect of phosphate application on lupin establishment, 89GE99. The effect of seeding technique, depth of sowing, seed soil contact and fungicide on lupin establishment on course sands, 89GE9. Integrated control strategy of Rhizoctonia hypocotyl root rot of lupins, 89GE11, 89GE12, 89GE12B, 89GE13, 89GE14. Strategies for lupin patch control, 89EC7 and 89GE15. The effect of seed size and sowing rate on lupin establishment, 89C1, 89GE6, 89GE7, 89EC5, 89BA34, 89TS49, 89GE10, 89EC4, 89GE4,


Serradella Evaluations, L. Cransberg Jan 1989

Serradella Evaluations, L. Cransberg

Experimental Summaries - Plant Research

Trial 85AL56

Location: South Sterlings.

Serradella line evaluation - Stage 3.

To evaluate five promising lines selected from variety trials, in terms of herbage production and long term persistence.

Trial 88AL32

Location: Walpole.
Long season serradella evaluation.

To select productive and persistent serradella lines for the deep acidic sands in the very high rainfall zone on the south coast.

Trial 88AL31

Location: Takalarup.

Ryegrass species evaluation.

To investigate the potential of a range of ryegrasses, from short term to long term perennial, in the south coast environment.

Grass species evaluation

Location: Greenrange.

To identify both productive and persistent grasses for …