Kreeger ACOE 22 DE Bay Seston Report Final
➤ Gửi thông báo lỗi ⚠️ Báo cáo tài liệu vi phạmNội dung chi tiết: Kreeger ACOE 22 DE Bay Seston Report Final
Kreeger ACOE 22 DE Bay Seston Report Final
Analysis of Particulate Nutrients and Seston Weights from 2009 to 2011 at Delaware Bay Oyster StationsDanielle Kreeger, Ph.D.Academy of Natural Scienc Kreeger ACOE 22 DE Bay Seston Report Finalces of Drexel University August 28. 2013A final report prepared for Rutgers University as part of the U.S. Army Corps of Engineers Section 22 Delaware River and Bay Monitoring studyIntroductionPopulation dynamics of oysters, Crassostrea Virginia}, in the Delaware Estuary are governed by diverse phys Kreeger ACOE 22 DE Bay Seston Report Finalical and biological factors including salinity, disease prevalence and virulence, predation, recruitment, and food availability and quality. Sea levelKreeger ACOE 22 DE Bay Seston Report Final
rise associated with climate change has the potential when combined with physical alterations to the ecosystem (e.g., channel deepening), has the potAnalysis of Particulate Nutrients and Seston Weights from 2009 to 2011 at Delaware Bay Oyster StationsDanielle Kreeger, Ph.D.Academy of Natural Scienc Kreeger ACOE 22 DE Bay Seston Report Final(which could promote disease) or alter hydrology and associated food regimes (which could affect nutrition and production). As part of a 3-year study to assess oyster and sturgeon conditions in the Delaware River and Bay, the goal of this portion of the study was to characterize seasonal, inter-annu Kreeger ACOE 22 DE Bay Seston Report Finalal and spatial variability in food conditions for oysters in representative growing areas of Delaware Bay.The importance of food supply for larval andKreeger ACOE 22 DE Bay Seston Report Final
adult bivalves is widely recognized: however, little direct evidence exists for food limitation within estuaries, either for adult or larval stages. Analysis of Particulate Nutrients and Seston Weights from 2009 to 2011 at Delaware Bay Oyster StationsDanielle Kreeger, Ph.D.Academy of Natural Scienc Kreeger ACOE 22 DE Bay Seston Report Finall growth and metamorphosis (e.g., Gallager and Mann. 1986: Pernet et al.. 2003: Nevejan et al., 2003: Fernández-Reiriz et al., 2006). On the other hand, other studies have pointed to the importance of dietary protein for regulating growth of post-set juveniles (Kreeger and Langdon 1993) or for adult Kreeger ACOE 22 DE Bay Seston Report Finals at crucial points in the reproductive cycle, such as during gametogenesis (Kreeger 1993, Kreeger et al. 1995). Regardless of which biochemical constKreeger ACOE 22 DE Bay Seston Report Final
ituent limits production at different life stages and seasons, modeling work has provided support for the belief that both food quantity and food qualAnalysis of Particulate Nutrients and Seston Weights from 2009 to 2011 at Delaware Bay Oyster StationsDanielle Kreeger, Ph.D.Academy of Natural Scienc Kreeger ACOE 22 DE Bay Seston Report Finalve drawn upon a range of experimental literature (e.g., Thompson and Harrison, 1992; strathmann et al., 1993: Thompson et al., 1996: Baldwin and Newell. 1995: Hendriks et al.. 2003) in aggregate supporting this contention, but direct held evidence is limited (e.g.. Bos et al„ 2006).Oysters feed on m Kreeger ACOE 22 DE Bay Seston Report Finalicroparticulate material suspended in the water column (seston). Oyster productivity and reproductive condition can be affected by both food quantityKreeger ACOE 22 DE Bay Seston Report Final
and food quality. To assess food conditions for oysters, water samples were collected from representative areas containing oyster reefs, filtered, andAnalysis of Particulate Nutrients and Seston Weights from 2009 to 2011 at Delaware Bay Oyster StationsDanielle Kreeger, Ph.D.Academy of Natural Scienc Kreeger ACOE 22 DE Bay Seston Report Finalal (POM. represents food quantity). Additional filtered samples were fractionated for their proximate biochemical composition to determine particulate concentrations of protein, lipid and carbohydrate (represents food quality).Particulate protein, lipid and carbohydrate concentrations were contraste Kreeger ACOE 22 DE Bay Seston Report Finald among each other and as percentages of TSS and POM as further expressions of the bioavailable fractions available to support oyster growth and produKreeger ACOE 22 DE Bay Seston Report Final
ction. Data collected from this study were then used by Rutgers staff to update and refine hydrodynamical models of oyster production that includes foAnalysis of Particulate Nutrients and Seston Weights from 2009 to 2011 at Delaware Bay Oyster StationsDanielle Kreeger, Ph.D.Academy of Natural Scienc Kreeger ACOE 22 DE Bay Seston Report Finalled after a similar earlier assessment that occurred between May 2000 and March 2001. led by Versar. In the 2000 Versar study, seston quantity and quality, which were referred to as “nutrients.” were analyzed using methods developed by Dr. D. Kreeger, Academy of Natural Sciences. The 2009-2012 sampl Kreeger ACOE 22 DE Bay Seston Report Finaling program repeated the earlier assessment using the same seston analysis methods as in 2000, but with more stations (up to 18) and months (up to 9)Kreeger ACOE 22 DE Bay Seston Report Final
being sampled to provide better resolution of temporal and spatial variation.MethodsField Sampling Program. To examine seston quantity and quality, waAnalysis of Particulate Nutrients and Seston Weights from 2009 to 2011 at Delaware Bay Oyster StationsDanielle Kreeger, Ph.D.Academy of Natural Scienc Kreeger ACOE 22 DE Bay Seston Report Finaln of February and December. Sites were accessed via the F/V Dredge Monster. At each site three replicate 1-gallon jugs of water were retrieved from 30.5 cm below the surface with an Eheim Universal Model 1048 submersible pump and flexible rubber tubing. Jugs of water were kept at ambient temperature Kreeger ACOE 22 DE Bay Seston Report Final in coolers while being transported back to the laboratory. Detailed station locations and notes on the 2009-2011 field sampling can be obtained fromKreeger ACOE 22 DE Bay Seston Report Final
Rutgers.Seston Collection. Seston is defined as microparticulate material too small to be seen by the human eye. These are suspended particles that arAnalysis of Particulate Nutrients and Seston Weights from 2009 to 2011 at Delaware Bay Oyster StationsDanielle Kreeger, Ph.D.Academy of Natural Scienc Kreeger ACOE 22 DE Bay Seston Report Final 100-pm sieve. Depending on TSS concentrations, typically between 100 and 1000 ml of water are needed to obtain enough seston per filter for accurate analysis.Methods for collecting seston from water samples are described in detail in DK-SOP-23 (Rev. 2. 8/06). This is a standard operating procedure Kreeger ACOE 22 DE Bay Seston Report Finalprepared by D. Kreeger and it is available upon request. In summary, seston was collected on prepared glass fiber filters using vacuum filtration of wKreeger ACOE 22 DE Bay Seston Report Final
ater collected in 4-L jugs from field sampling stations. Rutgers staff performed the filtrations within 24 hours of collection, and filters containingAnalysis of Particulate Nutrients and Seston Weights from 2009 to 2011 at Delaware Bay Oyster StationsDanielle Kreeger, Ph.D.Academy of Natural Scienc Kreeger ACOE 22 DE Bay Seston Report Finaln sampled at a given time,) three replicate jugs were filled and then filtered. From each jug. four replicate seston samples were collected on 0.7-pm retention glass fiber filters (47 mm diameter: Whatman type GF/F or equivalent.) The replicate filtration2 I Delaware Bay Seston 2009-2011 - Kreeger41 Kreeger ACOE 22 DE Bay Seston Report Final514of each water sample (jug) onto four filters allowed for the separate analysis of seston weight, protein content, carbohydrate content and lipid coKreeger ACOE 22 DE Bay Seston Report Final
ntent (Fig. 1).Filters were prepared in advance. Filters were pre-combusted at 450°C for at least 24 hr prior to seston filtration. A sufficient numbeAnalysis of Particulate Nutrients and Seston Weights from 2009 to 2011 at Delaware Bay Oyster StationsDanielle Kreeger, Ph.D.Academy of Natural Scienc Kreeger ACOE 22 DE Bay Seston Report Finaled for weight-on-ignition and the remaining three filter replicates were used for biochemistry. The replicate to be used for weight-on-ignition was preweighed. The same balance was used before and after filtering seston. Weights were measured only on desiccated samples.Seston Analysis. One of the fo Kreeger ACOE 22 DE Bay Seston Report Finalur replicate seston-coated filters per water jug was used for weight-on-ignition analysis, one for protein content, one for lipid content and onefor cKreeger ACOE 22 DE Bay Seston Report Final
arbohydrate content. The weight-on-ignition assay assessed the total seston weight per unit volume (i.e., TSS concentration) and the seston organic coAnalysis of Particulate Nutrients and Seston Weights from 2009 to 2011 at Delaware Bay Oyster StationsDanielle Kreeger, Ph.D.Academy of Natural Scienc Kreeger ACOE 22 DE Bay Seston Report Finaln below. Seston filters for weight analysis were dried at 60:C for >2 days and weighed (±0.01mg: Sartorius M-9001). Filters were then combusted in a muffle furnace for 48 hr at 450 'C and weighed again on the same balance.Figure 1. Diagram showing how replicate water subsamples from a single water s Kreeger ACOE 22 DE Bay Seston Report Finalample are filtered onto four separate glass fiber filters.Concentrations of PM (a.k.a. total suspended solids. TSS) and POM were calculated with the fKreeger ACOE 22 DE Bay Seston Report Final
ollowing formulae:PM (mg/L) = [(dry filter+seston weight) - (dry filter weight)] / (filtered volume)POM = PM - [(ash filter+seston weight) - (dry filtAnalysis of Particulate Nutrients and Seston Weights from 2009 to 2011 at Delaware Bay Oyster StationsDanielle Kreeger, Ph.D.Academy of Natural Scienc Kreeger ACOE 22 DE Bay Seston Report Finaleparate replicate filters from each water sample. This proximate biochemical composition was determined using published methods that have been adapted by Kreeger et al. (1997). Protein was measured spectrophotometrically using the bicinchonic acid modification (Pierce test kit. 23225) of the procedu Kreeger ACOE 22 DE Bay Seston Report Finalre of Lowry et al. (1951). standardized with bovine serum albumen3 I Delaware Bay Seston 2009-2011 - Kreeger41514(Pierce 23210). A microplate reader wKreeger ACOE 22 DE Bay Seston Report Final
as used for spectrophotometry at a wavelength of 640 nm.Carbohydrates were quantified spectrophotometrically (wavelength 480 nm) using the method of DGọi ngay
Chat zalo
Facebook