Rates of decrease of polychlorinated biphenyl concentrations in five species of Lake Michigan salmonids

1999 ◽  
Vol 56 (1) ◽  
pp. 53-59 ◽  
Author(s):  
E Conrad Lamon III ◽  
S R Carpenter ◽  
C A Stow
Keyword(s):  
Natural Resources ◽  
Salmo Trutta ◽  
Lake Michigan ◽  
Lake Trout ◽  
Polychlorinated Biphenyl ◽  
Growth Parameters ◽  
Growth Parameter ◽  
First Order ◽  
Rate Of Increase ◽  
Concentration Changes

Dynamic linear models (DLM) were used to study time trends in annual average polychlorinated biphenyl (PCB) concentrations in five species of Lake Michigan salmonids using data collected from 1972 to 1994 by both the Michigan Department of Natural Resources and the Wisconsin Department of Natural Resources. DLMs use an adaptive fitting procedure to track changes over time in both the level (mean) of the series and the rate of increase or decline (growth rate), in contrast with other approaches that fit fixed parameters. We used DLMs to provide retrospective time series of estimates of rates of decline in PCB concentrations. Growth parameters indicate that PCB declines have slowed more than first-order models fit in the mid-1980s would predict. Growth parameters for brown trout (Salmo trutta) and rainbow trout (Oncorhynchus mykiss) increased only slightly, indicating the most consistency with first-order dynamics. Coho (Oncorhynchus kisutch) and chinook salmon (Oncorhynchus tshawytscha) showed a pattern of high rates of decline in the early to mid-1980s followed by a period of slower PCB concentration changes. The temporal pattern of rates of decline for lake trout (Salvelinus namaycush) stood apart from the other species, with a growth parameter that increased steadily during the entire period of record.

An examination of the PCB: lipid relationship among individual fish

1997 ◽  
Vol 54 (5) ◽  
pp. 1031-1038
Author(s):  
C A Stow ◽  
L J Jackson ◽  
J F Amrhein
Keyword(s):  
Salmo Trutta ◽  
Lake Michigan ◽  
Oncorhynchus Tshawytscha ◽  
Lake Trout ◽  
Coho Salmon ◽  
Salvelinus Namaycush ◽  
Rainbow Trout Oncorhynchus Mykiss ◽  
Strong Linear Correlation ◽  
Brown Trout Salmo Trutta ◽  
The Relationship

We examined data from 1984 to 1994 for five species of Lake Michigan salmonids to explore the relationship between total PCB concentration and percent lipid. When we compared mean species lipid and PCB values, we found a strong linear correlation. When we compared values among individuals, we found modest positive PCB:lipid associations in brown trout (Salmo trutta), chinook salmon (Oncorhynchus tshawytscha), coho salmon (Oncorhynchus kisutch), and rainbow trout (Oncorhynchus mykiss) collected during spawning, but positive associations were not apparent among nonspawning individuals. Lake trout (Salvelinus namaycush) exhibited no discernible PCB:lipid relationship. Our results are not incompatible with previous observations that contaminants are differentially partitioned into lipids within a fish, but these results do suggest that lipids are not a major factor influencing contaminant uptake.

scholarly journals Pertumbuhan dan Struktur Umur Kerang Kepah (Meretrix meretrix) di Kampung Nipah Desa Sei Nagalawan Kecamatan Perbaungan Kabupaten Serdang Bedagai

2017 ◽  
Vol 4 (2) ◽  
pp. 316
Author(s):  
Nafi Sakila ◽  
Dinda Ayu Ramadhani ◽  
Ani Suryanti
Keyword(s):  
Natural Resources ◽  
Random Sampling ◽  
Growth Parameters ◽  
Growth Parameter ◽  
Sampling Technique ◽  
Simple Random Sampling ◽  
Sampling Time ◽  
Size Group ◽  
Age Group ◽  
Von Bertalanffy

Sei Nipah has enormous potential for natural resources. Natural resources that serve as the main livelihood in fulfilling daily needs in Kampung Nipah is shellfish. Shellfish (M. meretrix) is one of the shells that many interested by the surrounding community. The purpose of this research is to know growth parameter and age group of shellfish (M. meretrix) in Kampung Nipah. The sampling technique was done randomly (simple random sampling). Sampling time is done at low tide. Sampling was conducted in March - May 2017. The results showed differences in the length of different shells each month. The size group of shellfish (M. meretrix) found only one size group during the three months of the study. Analysis of shellfish growth parameters based on data of long frequency distribution showed length of infiniti (L?) 33,10 mm and growth growth (K) that was 1,21 per month. Von Bertalanffy Growth Parameters Lt = 33.1 (1-e [-1.21 (t + 0.12)]) Long infiniti size is seen the growth of shellfish shells can no longer be worked Shells reach maximum length at the age of 13 months with a shell length of 33.10 mm.The youthful shells have rapid growth and as age increases, when it reaches old age the rate of growth will slow even.

Predation and Production by Salmonine Fishes in Lake Michigan, 1978–88

1991 ◽  
Vol 48 (5) ◽  
pp. 909-922 ◽  
Author(s):  
Donald J. Stewart ◽  
Myriam Ibarra
Keyword(s):  
Conversion Efficiency ◽  
Chinook Salmon ◽  
Salmo Trutta ◽  
Lake Michigan ◽  
Lake Trout ◽  
Biomass Conversion ◽  
Average Weight ◽  
Alosa Pseudoharengus ◽  
Brown Trout Salmo Trutta ◽  
Diet Shifts

A marked decline of alewife (Alosa pseudoharengus) in Lake Michigan during 1981–83 led to diet shifts by coho (Oncorhynchus kisutch) and chinook salmon (O. tshawytscha) from feeding primarily on large alewife to eating proportionately more immature alewives and other prey. Diets of lake trout (Salvelinus namaycush) did not change greatly during that period. Population biomass conversion efficiency averaged 24.5% for coho and 16.6% for lake trout. Chinook salmon suffered an apparent 20% decline in gross conversion efficiency of biomass (25.1 to 20.8%) and a 25% decline in average weight of sport-caught fish. We infer that chinook salmon growth was inhibited by insufficient forage available to them. A simulation of chinook salmon feeding on bloater (Coregonus hoyi) at 8 °C suggested that such behavior could lead to further declines in growth rates. Extension of modeling results to include approximations for brown trout (Salmo trutta) and rainbow trout (O. mykiss) revealed peaks in total annual salmonine predation of 71 000 t in 1983 and 76 000 t in 1987. The alewife was 70% of all prey eaten by salmonines in 1987–88. Lakewide gross production by salmonines was 15 300 t (or 0.27 g∙m−2) in 1987. Ratios of annual gross production to average monthly population biomass were 1.6 for chinook, 1.15 for coho, and only 0.6 for lake trout.

Endohelminths of salmonids from two localities in eastern Lake Michigan, with emphasis on Echinorhynchus salmonis

1989 ◽  
Vol 67 (6) ◽  
pp. 1604-1607 ◽  
Author(s):  
Patrick M. Muzzall
Keyword(s):  
Chinook Salmon ◽  
Salmo Trutta ◽  
Lake Michigan ◽  
Oncorhynchus Tshawytscha ◽  
Lake Trout ◽  
Coho Salmon ◽  
Oncorhynchus Kisutch ◽  
Salvelinus Namaycush ◽  
Salmo Gairdneri ◽  
Brown Trout Salmo Trutta

Adult salmonids (101 chinook salmon, Oncorhynchus tshawytscha; 7 coho salmon, Oncorhynchus kisutch; 56 lake trout, Salvelinus namaycush; 6 steelhead, Salmo gairdneri; and 2 brown trout, Salmo trutta) were collected from eastern Lake Michigan (Ludington and Manistee, Michigan) in July–September 1986, and examined for helminths. Eight species (three Cestoda, three Nematoda, two Acanthocephala) were found in the digestive tract and other viscera. Echinorhynchus salmonis and Eubothrium salvelini were the most common helminths found. The intensity of E. salmonis significantly increased as chinook salmon became older and longer.

Why Are the PCB Concentrations of Salmonine Individuals from the Same Lake So Highly Variable?

1994 ◽  
Vol 51 (4) ◽  
pp. 800-807 ◽  
Author(s):  
Charles P. Madenjian ◽  
Stephen R. Carpenter ◽  
Peter S. Rand
Keyword(s):  
Rainbow Trout ◽  
Lake Michigan ◽  
Lake Trout ◽  
Polychlorinated Biphenyl ◽  
Accumulation Rate ◽  
Assimilation Efficiency ◽  
Growth Efficiency ◽  
Rainbow Trout Oncorhynchus Mykiss ◽  
Trout Population ◽  
Gross Growth Efficiency

An individual-based model (IBM) was applied to the Lake Michigan rainbow trout (Oncorhynchus mykiss) population, with the objectives of explaining the observed variation in growth and in polychlorinated biphenyl (PCB) concentration within the population. When variation in prey PCB concentration was incorporated into the model, variability in PCB concentration among individual rainbow trout was fully explained by the IBM. Although number of spawnings and number of years spent in a stream prior to first entering the lake were factors in determining growth, these life history characteristics appeared to have only a minor impact on PCB accumulation rate in rainbow trout. The IBM application to the rainbow trout population was compared with an application to the Lake Michigan lake trout (Salvelinus namaycush) population. Modeling results indicated that the lower observed PCB concentrations in rainbow trout compared with lake trout were chiefly due to greater longevity in lake trout. The IBM simulations identified gross growth efficiency, assimilation efficiency of PCBs from food, and diet as other important sources of variability in salmonine PCB concentrations.

A new approach toward evaluation of fish bioenergetics models

2000 ◽  
Vol 57 (5) ◽  
pp. 1025-1032 ◽  
Author(s):  
Charles P Madenjian ◽  
Daniel V O'Connor ◽  
David A Nortrup
Keyword(s):  
Food Consumption ◽  
Lake Michigan ◽  
Lake Trout ◽  
Polychlorinated Biphenyl ◽  
Assimilation Efficiency ◽  
Osmerus Mordax ◽  
Alosa Pseudoharengus ◽  
Rainbow Smelt ◽  
New Approach ◽  
Bioenergetics Model

A new approach was used to evaluate the Wisconsin bioenergetics model for lake trout (Salvelinus namaycush). Lake trout in laboratory tanks were fed alewife (Alosa pseudoharengus) and rainbow smelt (Osmerus mordax), prey typical of lake trout in Lake Michigan. Food consumption and growth by lake trout during the experiment were measured. Polychlorinated biphenyl (PCB) concentrations of the alewife and rainbow smelt, as well as of the lake trout at the beginning and end of the experiment, were determined. From these data, we calculated that lake trout retained 81% of the PCBs contained within their food. In an earlier study, application of the Wisconsin lake trout bioenergetics model to growth and diet data for lake trout in Lake Michigan, in conjunction with PCB data for lake trout and prey fish from Lake Michigan, yielded an estimate of PCB assimilation efficiency from food of 81%. This close agreement in the estimates of efficiency with which lake trout retain PCBs from their food indicated that the bioenergetics model was furnishing accurate predictions of food consumption by lake trout in Lake Michigan.

Leaching Kinetics of Atrazine and Inorganic Chemicals in Tilled and Orchard Soils

2014 ◽  
Vol 28 (2) ◽  
pp. 231-237 ◽  
Author(s):  
Lech W. Szajdak ◽  
Jerzy Lipiec ◽  
Anna Siczek ◽  
Artur Nosalewicz ◽  
Urszula Majewska
Keyword(s):  
Reaction Rate ◽  
Inorganic Compounds ◽  
Model Performance ◽  
Order Reaction ◽  
First Order Reaction ◽  
Order Kinetic ◽  
Time Data ◽  
First Order ◽  
Concentration Changes ◽  
Reaction Constants

Abstract The aim of this study was to verify first-order kinetic reaction rate model performance in predicting of leaching of atrazine and inorganic compounds (K+1, Fe+3, Mg+2, Mn+2, NH4 +, NO3 - and PO4 -3) from tilled and orchard silty loam soils. This model provided an excellent fit to the experimental concentration changes of the compounds vs. time data during leaching. Calculated values of the first-order reaction rate constants for the changes of all chemicals were from 3.8 to 19.0 times higher in orchard than in tilled soil. Higher first-order reaction constants for orchard than tilled soil correspond with both higher total porosity and contribution of biological pores in the former. The first order reaction constants for the leaching of chemical compounds enables prediction of the actual compound concentration and the interactions between compound and soil as affected by management system. The study demonstrates the effectiveness of simultaneous chemical and physical analyses as a tool for the understanding of leaching in variously managed soils.

scholarly journals Host-Plant Variations Affect the Biotic Potential, Survival, and Population Projection of Myzus persicae (Hemiptera: Aphididae)

Insects ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 375
Author(s):  
Muhammad Yasir Ali ◽  
Tayyaba Naseem ◽  
Muhammad Arshad ◽  
Ijaz Ashraf ◽  
Muhammad Rizwan ◽  
...  
Keyword(s):  
Myzus Persicae ◽  
Growth Parameters ◽  
Population Projection ◽  
Chili Pepper ◽  
Intrinsic Rate Of Increase ◽  
Economic Damage ◽  
Pepper Plant ◽  
Net Reproductive Rate ◽  
Rate Of Increase ◽  
Wide Range

The green peach aphid, Myzus persicae Sulzer (Hemiptera: Aphididae), a polyphagous insect pest is a major threat to a wide range of crops worldwide. Aiming to evaluate the life history traits of M. persicae, feeding on different host plants, we used five vegetables: cabbage, Brassica oleracea (Brassicaceae); chinese cabbage, B. rapa (Brassicaceae); chili pepper, Capsicum annum (Solanaceae); crown daisy, Chrysanthemum coronarium (Asteraceae); and eggplant, Solanum melongena (Solanaceae). TWOSEX-MSchart software was used for the statistical analysis about the age-stage, two-sex life table theory. The highest fecundity (69.65 individuals) rate of M. persicae, intrinsic rate of increase (r = 0.425 d−1), finite rate of increase (λ = 1.531 d−1), net reproductive rate (R0 = 69.65 offspring), and shortest mean generation time (T = 9.964 d) were recorded on the chili pepper plant. Whereas, lower fitness occurred on cabbage. The findings attained from population growth parameters indicate that chili pepper is the most susceptible plant, while cabbage is resistant to aphids. Population projection results also supported this statement, as the final total population size on cabbage was significantly lower than other plants. The reported information would be useful for devising integrated pest management programs, particularly those involving M. persicae. This information also suggests the adaptability of M. persicae causing economic damage to these vegetable cultivars.

scholarly journals High-resolution glacial and deglacial record of atmospheric methane by continuous-flow and laser spectrometer analysis along the NEEM ice core

2013 ◽  
Vol 9 (6) ◽  
pp. 2579-2593 ◽  
Author(s):  
J. Chappellaz ◽  
C. Stowasser ◽  
T. Blunier ◽  
D. Baslev-Clausen ◽  
E. J. Brook ◽  
...  
Keyword(s):  
High Resolution ◽  
Continuous Flow ◽  
Ice Core ◽  
Rate Of Change ◽  
Atmospheric Methane ◽  
Data Set ◽  
Rate Of Increase ◽  
Concentration Changes ◽  
Cross Dating ◽  
Laser Spectroscopic

Abstract. The Greenland NEEM (North Greenland Eemian Ice Drilling) operation in 2010 provided the first opportunity to combine trace-gas measurements by laser spectroscopic instruments and continuous-flow analysis along a freshly drilled ice core in a field-based setting. We present the resulting atmospheric methane (CH4) record covering the time period from 107.7 to 9.5 ka b2k (thousand years before 2000 AD). Companion discrete CH4 measurements are required to transfer the laser spectroscopic data from a relative to an absolute scale. However, even on a relative scale, the high-resolution CH4 data set significantly improves our knowledge of past atmospheric methane concentration changes. New significant sub-millennial-scale features appear during interstadials and stadials, generally associated with similar changes in water isotopic ratios of the ice, a proxy for local temperature. In addition to the midpoint of Dansgaard–Oeschger (D/O) CH4 transitions usually used for cross-dating, sharp definition of the start and end of these events brings precise depth markers (with ±20 cm uncertainty) for further cross-dating with other palaeo- or ice core records, e.g. speleothems. The method also provides an estimate of CH4 rates of change. The onsets of D/O events in the methane signal show a more rapid rate of change than their endings. The rate of CH4 increase associated with the onsets of D/O events progressively declines from 1.7 to 0.6 ppbv yr−1 in the course of marine isotope stage 3. The largest observed rate of increase takes place at the onset of D/O event #21 and reaches 2.5 ppbv yr−1.

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