Marine Fishes in Fresh and Brackish Waters of Virginia Rivers

In the fresh and brackish waters of the James, Chickahominy, Pamunkey, Mattaponi and Rappahannock rivers in Virginia, 18 species of marine fishes ( exclusive of anadromous and catadromus forms) have been collected. Gunter\u27s (1942) exhaustive survey of the occurrence of Atlantic coast marine fishes in fresh water is here amplified for the most important tidal rivers of Virginia. Since 1949 intensive collecting has been done in brackish and tidal fresh waters of the Pamunkey and Rappahannock rivers, and numerous. collections have been made in the James, Chickahominy, and Mattaponi

Relative abundance of young fishes in Virginia estuaries

Watermen have expressed the opinion that commercial fish production varies considerably from one Virginia estuary to another. Preliminary surveys of the young fishes present in the various rivers have suggested that the relative abundance of young fishes also differs from river to river. The surface trawl (Massmann, Ladd, and McCutcheon, 1952) has been used to obtain quantitative information on the distribution and relative abundance of young fishes in five major Virginia estuaries

Lower James River pollution study, City Point to Chickahominy, August 6 - September 6, 1951 : a preliminary report of findings, conclusions and recommendations

Hopewell,m Virginia.is ·a highly industrialized city, the Celanese Corporation of .America, the Continental Can Company, the Hercules Powder Company and the Solvay Process: Division of· Allied Chemical and Dye Corporation having plants there. All of these plants have industrial and human wastes, the combined amount of which is great from. the standpoint of both volume and strength. In addition, there. are human wastes from the City cf Hopewell and its suburbs in Prince George County and from Camp Lee. All of those wastes, sewage and industrial are discharged into the James River, Bailey Creek and into other tributaries of the two. Primary treatment is given the wastes at Camp Lee; the others are discharged untreated. The location of all discharges in the Hopewell vicinity are shown in Figure I. With the exception of Bailey Creek, the impact of these wastes on the streams they enter was largely unknown, prior to this study. For many years Bailey Creek has been organized as an open sewer. Following passage of the Virginia. State Water Control -Law in 1946, the Hopewell industries all began programs leading to reduction of wastes they discharged. In order for them to determine the extent to which such reductions must ultimately be carried, it soon became apparent that information was needed regarding the effect of their wastes on the James River. During: the summer of 1951::the Hopowell industries, through the Hopewell Manufactures Association requested.the Water·Control Board\u27s help in making a study of the stream in the· Hopewell vicinity in an attempt to answer this question. The Board\u27s staff agreed to lend such assistance as was possible, and the initial phases of such a study were completed during the period ·August 6 - September 6, 1951

Abundance, age, and fecundity of shad, York River, VA, 1953-1959

A study of the American shad fishery of the York River Va. during 1959 showed an estimated total catch of 463,000 pounds, a fishing rate of 55.2 percent, and a total population of 839,000 pounds. Additional estimates of catch and effort were used to calculate fishing rate and population size for each year 1953 through 1958. Analyses of scales showed that most shad spawn at 3, 4, and 5 years of age and approximately, 23 percent of the fish caught during the 1957-59 seasons had spawned the previous year. The number of ova produced by. York River shad ranged from 169,000 to 436,000 per fish

The River Shrimp, Macrobrachium ohione (Smith), in Virginia

The \u27\u27river shrimp belonging to the genus Macrobrachium, which range in length from 34 to more than 230 mm., are not to be confused with the smalier glass shrimp belonging to the genus Palaemonetes, at least one species of which is a common form in the waters of the Piedmont and Coastal Plain of Virginia

The fishes of the tidewater section of the Pamunkey River, Virginia

The distribution of the fish fauna of the tidewater section of most of the rivers that flow into Chesapeake Bay is poorly known. Indeed, this is true for practically all the great rivers tributary to the Atlantic from the Hudson southward to the Savannah. The few investigations usually have concentrated on commercial species and our understanding of distribution has been inferred from the knowledge of nearby Coastal Plain streams reported in such studies as those by Hildebrand and Schroeder (1928), Fowler (1945), Raney (1950), and Massmann, Ladd, McCutcheon (1952). In 1949 the junior author began a study of the spawning and early life history of shad in the Pamunkey and other nearby Virginia rivers and collected witli seines at numerous locations in the tidal area. After exploratory seining, many of the stations were visited at almost weekly intervals during the period June 28 to September 29, 1949. Since that time additional collections have been made at established stations on the Pamunkey indicated on the map (Fig. 1)

Comparative judgments of secondary school principals about collective bargaining as a function of prior non-management experience

Collective bargaining has been in Iowa for only a short time. 1 Personal involvement and curiosity about the topic provided the intrinsic motivation for this study, The author organized and led a teachers\u27 association in the first bargaining year and served as a grievance officer for that association for three years. Based on this involvement, the researcher was interested in ascertaining how administrator opinions have been affected by previous experiences with the bargaining process. What changes in opinions have new Iowa school administrators had when they changed sides of the bargaining table

The fundamental equation of eddy covariance and its application in flux measurements

A fundamental equation of eddy covariance (FQEC) is derived that allows the net ecosystem exchange (NEE) N̅s of a specified atmospheric constituent s to be measured with the constraint of conservation of any other atmospheric constituent (e.g. N2, argon, or dry air). It is shown that if the condition │N̅s│ ˃˃ │X̅s│ │N̅co2│is true, the conservation of mass can be applied with the assumption of no net ecosystem source or sink of dry air and the FQEC is reduced to the following equation and its approximation for horizontally homogeneous mass fluxes: N̅s = c̅dw’X’s│h + ∫h0 c̅d(z) ∂Xs/∂t dz + ∫h0 [X̅s (z)- X̅s (h)] ∂̅c̅d̅/∂t dz = c̅d̅(h) {w̅’X̅’s│h + ∫h0 ∂Xs/∂t dz}. Here w is vertical velocity, c molar density, t time, h eddy flux measurement height, z vertical distance and Xs= cs/cd molar mixing ratio relative to dry air. Subscripts s, d and CO2 are for the specified constituent, dry air and carbon dioxide, respectively. Primes and overbars refer to turbulent fluctuations and time averages, respectively. This equation and its approximation are derived for non-steady state conditions that build on the steady-state theory of Webb, Pearman and Leuning (WPL; Webb et al., 1980. Quart. J. R. Meteorol. Soc. 106, 85–100), theory that is widely used to calculate the eddy fluxes of CO2 and other trace gases. The original WPL constraint of no vertical flux of dry air across the EC measurement plane, which is valid only for steady-state conditions, is replaced with the requirement of no net ecosystem source or sink of dry air for non-steady state conditions. This replacement does not affect the ‘eddy flux’ term c̅d̅w̅’X̅’s s but requires the change in storage to be calculated as the ‘effective change in storage’ as follows: ∫h0 ∂̅c̅s̅/ ∂̅t̅ dz – X̅s(h) ∫h0 ∂̅c̅d̅/∂t dz = ∫h0 c̅d̅ (z) - ∂Xs/∂t dz + ∫h0 [X̅s (z)- X̅s (h)] ∂̅c̅d̅/∂t dz= c̅d (h) ∫h0 ∂Xs/∂t dz. Without doing so, significant diurnal and seasonal biases may occur. We demonstrate that the effective change in storage can be estimated accurately with a properly designed profile of mixing ratio measurements made at multiple heights. However further simplification by using a single measurement at the EC instrumentation height is shown to produce substantial biases. It is emphasized that an adequately designed profile system for measuring the effective change in storage in proper units is as important as the eddy flux term for determining NEE

The fundamental equation of eddy covariance and its application in flux measurements

A fundamental equation of eddy covariance (FQEC) is derived that allows the net ecosystem exchange (NEE) N̅s of a specified atmospheric constituent s to be measured with the constraint of conservation of any other atmospheric constituent (e.g. N2, argon, or dry air). It is shown that if the condition │N̅s│ ˃˃ │X̅s│ │N̅co2│is true, the conservation of mass can be applied with the assumption of no net ecosystem source or sink of dry air and the FQEC is reduced to the following equation and its approximation for horizontally homogeneous mass fluxes: N̅s = c̅dw’X’s│h + ∫h0 c̅d(z) ∂Xs/∂t dz + ∫h0 [X̅s (z)- X̅s (h)] ∂̅c̅d̅/∂t dz = c̅d̅(h) {w̅’X̅’s│h + ∫h0 ∂Xs/∂t dz}. Here w is vertical velocity, c molar density, t time, h eddy flux measurement height, z vertical distance and Xs= cs/cd molar mixing ratio relative to dry air. Subscripts s, d and CO2 are for the specified constituent, dry air and carbon dioxide, respectively. Primes and overbars refer to turbulent fluctuations and time averages, respectively. This equation and its approximation are derived for non-steady state conditions that build on the steady-state theory of Webb, Pearman and Leuning (WPL; Webb et al., 1980. Quart. J. R. Meteorol. Soc. 106, 85–100), theory that is widely used to calculate the eddy fluxes of CO2 and other trace gases. The original WPL constraint of no vertical flux of dry air across the EC measurement plane, which is valid only for steady-state conditions, is replaced with the requirement of no net ecosystem source or sink of dry air for non-steady state conditions. This replacement does not affect the ‘eddy flux’ term c̅d̅w̅’X̅’s s but requires the change in storage to be calculated as the ‘effective change in storage’ as follows: ∫h0 ∂̅c̅s̅/ ∂̅t̅ dz – X̅s(h) ∫h0 ∂̅c̅d̅/∂t dz = ∫h0 c̅d̅ (z) - ∂Xs/∂t dz + ∫h0 [X̅s (z)- X̅s (h)] ∂̅c̅d̅/∂t dz= c̅d (h) ∫h0 ∂Xs/∂t dz. Without doing so, significant diurnal and seasonal biases may occur. We demonstrate that the effective change in storage can be estimated accurately with a properly designed profile of mixing ratio measurements made at multiple heights. However further simplification by using a single measurement at the EC instrumentation height is shown to produce substantial biases. It is emphasized that an adequately designed profile system for measuring the effective change in storage in proper units is as important as the eddy flux term for determining NEE