Physical Sciences and Mathematics Commons^™

Influence Of Zooplankton Grazing On Free Dissolved Enzymes In The Sea, Alexander B. Bochdansky, Staša Puškarić, Gerhard J. Herndl

OES Faculty Publications

In the Northern Adriatic Sea, extracellular enzymatic activity was measured during a Lagrangian study following a drifting buoy for 40 h. Dissolved free enzymatic activity represented 20 to 70% of total activity depending on the type of enzyme. alpha- and beta-glucosidases exhibited a significantly higher free activity than proteolytic enzymes. In subsequent laboratory experiments we investigated the effect of zooplankton on the free enzyme pool. The 4-step approach included: (1) determination of the enzymatic activities in copepods (mainly Acartia clausi); (2) enzymatic activity in fecal pellets; (3) short- and long-term grazing experiments; and (4) degradability of free glucosidase in seawater. …

Elimination Of Dissolved Sulfide Interference In The Flow-Injection Determination Of Sigma-Co2 By Addition Of Molybdate, Rigel L. Lustwerk, David J. Burdige

OES Faculty Publications

A previously described flow injection method for the analysis of ΣCO₂ included the addition of ZnCl₂ to some samples before analysis in order to precipitate dissolved sulfide (which interferes with the method) as ZnS. However, the use of Zn²⁺ in samples with high concentrations of dissolved sulfide causes the coprecipitation of ZnCO₃, and in our experience with this technique, ZnCO₃ also precipitates even in the absence of dissolved sulfide. The addition of molybdate effectively complexes dissolved sulfide without interfering with the determination of ΣCO2 by this technique.

Land Resources Of The Bencubbin Area, Gerard J. Grealish, John Wagnon

Land resources series

This survey of the Bencubbin area is part of the Agriculture Western Australia's regional land resource mapping program, and covers approximately 1.5 million hectares in the Merredin, Trayning, Koorda, Mount Marshall, Mukinbudin, Westonia and Nungarin Shires of Western Australia. The climate is Mediterranean, with hot dry summers and cool winters. Land is used for winter cereal production and grazing, and about 60% is cropped each year. Wheat is the main crop and is grown in rotation with lupins, field peas, barley and medic pasture. This report provides primary and interpreted information on the character and capability of the land, for …

Soil Information Sheets For Ravensthorpe And Part Of The Jerramungup Agricultural Areas, Tim D. Overheu, Landcare Western Australia.

Agriculture reports

The soil information sheets produced for the Ravensthorpe Land Conservation District provide an easy reference guide to the soils for part of the Jerramungup and Ravensthorpe agricultural areas, and provide land use and soil management recommendations. Soil data are shown on the front of the sheet, and land use and land management information is given on the back. The information should be used as a guide, and encourage the user to seek further information through the relevant people and organisations.

Remnant Vegetation Inventory On The Southern Agricultural Areas Of Western Australia., G R. Beeston, G Mlodowski, A Sanders, D True

Resource management technical reports

Remnant vegetation mapping and its incorporation into a Geographical Information System (GIS) data base is the first stage in an overall documentation and promotion of conservation of remnant vegetation in Western Australia. The primary objective of this project being to determine the amount, distribution and regional location of native vegetation remaining on private land in the agricultural area of south-west Western Australia.

Native Vegetation Handbook For The Shire Of Cunderdin, Sarah J. Weaving

Native vegetation handbook series

This booklet provides land managers with information relating to the natural resources of the Shire of Cunderdin. This includes the existing vegetation, drainage systems and soils. Some of the problems relating to the management of natural vegetation resources in the Shire and possible solutions to these problems are discussed. The provision of this information will contribute to the long term viability of the agricultural landscape and the conservation of native vegetation within the Shire.

Native Vegetation Handbook For The Shire Of Trayning, Sarah J. Weaving

Native vegetation handbook series

This booklet provides land managers with information relating to the natural resources of the Shire of Trayning including the existing vegetation, drainage systems and soils. Some of the problems relating to the management of natural vegetation resources in the Shire of Trayning and possible solutions to these problems are also discussed. Provision of this information will contribute to the long term viability of the agricultural landscape and the conservation of native vegetation within the Shire.

Native Vegetation Handbook For The Shire Of Bruce Rock, Sarah J. Weaving

Native vegetation handbook series

This booklet provides land managers with information relating to the natural resources of the Shire of Bruce Rock including the existing vegetation, drainage systems and soils. Some of the problems relating to the management of natural vegetation resources in the Shire of Bruce Rock and possible solutions to these problems are also discussed. Provision of this information will contribute to the long term viability of the agricultural landscape and the conservation of native vegetation within the Shire.

Taphonomy Of Isocrinid Stalks: Influence Of Decay And Autotomy, Tomasz K. Baumiller, Ghislaine Llewellyn, Charles G. Messing, William I. Ausich

Marine & Environmental Sciences Faculty Articles

Stalks of isocrinid crinoids are differentiated into cirri-bearing columnals (nodals) and columnals lacking cirri (internodals). This skeletal differentiation allowed us to test whether stalk fragmentation is random or whether it occurs preferentially at a specific articulation. Our analyses indicate that the patterns of fragmentation in multicolumnal segments of extant isocrinids collected by submersible, by dredging, and in sediment samples, as well as those found as fossils, are nonrandom. The preferred plane of fragmentation corresponds to the synostosis, the articulation between a nodal and the internodal distal to it. In isocrinids this articulation has a characteristic morphology and is the site …

New Optical Cell Design For Laser Flash Photolysis Studies In Supercritical Fluids, Steven R. Goates, Milton L. Lee, Qin Ji, Edward M. Eyring, Rudi Van Eldik, Kedika Bal Reddy

Faculty Publications

A high-pressure optical cell has been designed that achieves an effective separation between the chemical sample and the pressurizing medium and system. This design limits possible sample contamination and catalytic effects under supercritical fluid sample conditions. Laser flash photolysis experiments were carried out on molybdenum hexacarbonyl dissolved in supercritical CO2. The thermal ring closure reaction of the species Mo(CO)5L, where L is 2,2- bipyridine was found to proceed at rates comparable to those measured previously in liquid benzene or toluene. Much larger activation volumes were found for the reaction in supercritical CO2 than in liquid toluene.

Time To Metamorphosis Of Blue Crab Callinectes Sapidus Megalopae: Effects Of Benthic Macroalgae, Robert D. Brumbaugh, John R. Mcconaugha

OES Faculty Publications

There is growing evidence that postlarvae (megalopae) of the blue crab Callinectes sapidus can slow the progression through the molt cycle while in offshore nursery grounds, and delay metamorphosis until reinvasion of coastal habitat occurs. However, the cues that trigger metamorphosis of megalopae are not well known. This study tested the hypothesis that the time to metamorphosis (TTM) from the postlarval megalops stage to the first crab stage is shortened in the presence of 2 potential macroalgal settlement substrates, Ulva lactuca (Chlorophyta), and Gracilaria spp. (Rhodophyta). Megalopae and test water were collected from 3 locations (offshore, at a coastal inlet, …

Regulating The Blue Crab, Callinectes Sapidus, Fishery In Virginia : Biological And Economic Concerns, James E. Kirkley, William D. Dupaul, Michael J. Oesterling

Reports

The blue crab, Callinectes sapiclus, fishery has been one of the most important fisheries of Virginia. The importance of the fishery in terms of commercial activities has substantially increased in recent years in response to declining resource levels of American Oyster, Crassostrea virginica, and a growing international and domestic demand for soft crabs, female hard crabs, and crab meat.

The actual economic importance of the fishery, however, is not well known. For example, what are the employment and earning levels generated by the fishery? What portion of a waterman's household income is derived from crabbing? How much does crabbing contribute …