The Ecotoxicological Impact Of Microplastics On Freshwater Invertebrates
The Ecotoxicological Impact ofMicroplastics on FreshwaterInvertebratesA thesis submitted for the degree of Doctor of PhilosophySchool of Biological SciencesRana Munketh Al-jaibachiDecember 2018
Word Template by Friedman & Morgan 2014For my parentswho funded my studyi
DECLARATIONThis dissertation is the result of my own work and includes nothing, which is theoutcome of work done in collaboration except where specifically indicated in the text. Ithas not been previously submitted, in part or whole, to any university of institution forany degree, diploma, or other qualification.Signed:Date:Rana Al-jaibachiiiWord Template by Friedman & Morgan 2014University of Reading
SUMMARY / ABSTRACTMicroplastics (MPs) are small plastic particles released directly from the use ofcosmetic products, or indirectly through the degradation of large plastic items underenvironmental conditions. Microplastics have been found in marine and freshwaterenvironments around the world, raising concerns about the long term impact on animalsand ecosystems in addition to recent discoveries of MPs entering the human food chain.The impacts of MP pollution on ecosystems and their functioning remain poorlyquantified and there is a paucity of information on the impacts of MPs in freshwaterecosystems, despite the broad range of pathways through which MPs can proliferate andthe extensive range of species which actively ingest MPs in these systems. This thesisaims to obtain key data on the uptake, fate and ecotoxicological impact of MPs onfreshwater invertebrates. Initially, MP uptake and chronic toxicity tests were gatheredby exposing the crustacean water flea Daphnia magna Straus 1820 (Cladocera) topolystyrene MPs of sizes 2 and 15 µm. The endpoints were mortality, growth andnumber of offspring. The results indicate that D. magna selectively uptake foodparticles over MPs, and that the toxicity was mainly linked to the availability of food.Moreover, a significant size dependent increase of toxicity was observed, withexposures to 2 µm sized particles being more toxic than 15 µm sized particles. Uptake,fate and toxicity of MPs were also studied in a holometabolous insect by exposing thecommon house mosquito Culex pipiens Linnaeus 1758 (Diptera) to polystyrene MPs ofsizes 2 and 15 µm. Results showed both particle sizes were readily taken up by larvalmosquitoes then transferred to the adults via pupae. There were more transfer of MPssize 2 µm compare it to 15 µm without any effecting on mortality and weight of adults.This work is the first to demonstrate that MPs can be transferred ontogenically throughorganisms with complex life histories, presenting a potential pathway for dispersal ofMPs into terrestrial environments. Laboratory studies were followed up with a fieldstudy exposing a small freshwater pond community to 15 µm polystyrene MPs. Theresults show that a high proportion of MPs accumulated in the sediment while only asmall amount remained in the water column, with a significant correlation between thenumber of MPs in the water and the freshwater invertebrate. The presence of MPs hadno real impact on the freshwater community, with season being a more importantvariable. Finally, the predatory ability of non-biting midge larvae, Chaoborus flavicans,towards larvae of C. pipiens mosquitoes loaded with 2 µm was quantitatively examinedWord Template by Friedman & Morgan 2014by linking MP trophic transfer with predation rates in a functional response framework.iii
Results demonstrated a lack of effect of MPs on predation rates and correlation numberivWord Template by Friedman & Morgan 2014of MPs transferred through predation.
ACKNOWLEDGEMENTSFirstly, I would like to express my sincere gratitude to my supervisor Prof. AmandaCallaghan or her continuous support of my Ph.D study and related research, for herpatience, motivation, and immense knowledge. Her guidance helped me in all the timeof research and writing of this thesis. I could not have imagined having a better advisorand mentor for my Ph.D study.Besides my advisor, I would like to thank the rest of my thesis committee: Dr GrahamHolloway and David Suprgon, for their insightful comments and encouragement, butalso for the hard question which incepted me to widen my research from variousperspectives.My sincere thanks also goes to Dr. Graham Luke, who gave microscopic training andprovide me access to the laboratory and microscopic facilities. Without his precioussupport it would not be possible to conduct this research.Additionally would like to thank Dr Ross Cuthbert on his collaboration and sharing theknowledge during our successful project.Also I thank my friends in the University of Reading. Specially in suit 8, Harbornbuilding.Last but not the least, I would like to thank my Husband Dr Husham Alnuaimi for hissupport also my family: my parents and to my brothers and sister for supporting meWord Template by Friedman & Morgan 2014spiritually throughout writing this thesis and my life in general.v
CONTENTSCHAPTER 1 GENERAL INTRODUCTION . 11.1 LITERATURE REVIEW . 31.2 WHAT ARE MICROPLASTICS? . 41.3 PRESENCE OF MICROPLASTICS IN MARINE ENVIRONMENT . 61.3.1 Ingestion and ecotoxicological impacts of microplastics on marine organisms. 101.3.2 Trophic transference of microplastics . 111.4 PRESENCE OF MICROPLASTICS IN FRESHWATER ENVIRONMENT. 131.4.1 Ingestion and ecotoxicological impact of microplastics on freshwaterorganisms. 171.5 EFFECT OF MPS ON NATURAL FRESHWATER ECOSYSTEMS . 291.6 DAPHNIA MAGNA AND ITS USE AS AN ECOTOXICOLOGICAL MODEL TO EXAMINE THEIMPACT OF MICROPLASTICS . 291.7 CULEXPIPIENS AND ITS USE AS AN ECOTOXICOLOGICAL MODEL TO EXAMINE THEIMPACT OF MICROPLASTICS . 331.8 AIM AND OBJECTIVES OF THE STUDY. 351.9 NOTE ON THE STRUCTURE OF THE THESIS. 36CHAPTER 2 IMPACT OF POLYSTYRENE MICROPLASTICS ON DAPHNIAMAGNA MORTALITY AND REPRODUCTION IN RELATION TO FOODAVAILABILITY . 382.1 INTRODUCTION . 392.2 MATERIALS AND METHODS . 412.2.1 Daphnia magna and Chlorella vulgaris culture. 412.2.2 Preparation of MPs . 422.2.3 Microplastic uptake . 422.2.4 Microplastic depuration . 422.2.5 Microplastic visual assessment . 432.2.6 Differential microplastic uptake under varying food regime . 432.2.7 Chronic toxicity tests—adults . 442.2.8 Chronic toxicity test—neonates . 452.2.9 Statistical methods . 452.3 RESULTS . 47viWord Template by Friedman & Morgan 20142.3.1 Uptake of MPs . 47
2.3.2 Depuration of MPs . 482.3.3 Differential microplastic uptake under varying food regime . 492.3.4 Mortality test—adults . 502.3.5 Reproduction test—adults . 512.3.6 Mortality rate—neonate. 522.3.7 Reproduction test—neonate . 542.3.8 Growth rate . 552.4 DISCUSSION . 562.5 CONCLUSIONS. 58CHAPTER 3 IMPACT OF 15 µM POLYSTYRENE MICROPLASTICS ONDAPHNIA MAGNA MORTALITY AND REPRODUCTION IN RELATION TOFOOD AVAILABILITY . 603.1 INTRODUCTION . 613.2 MATERIALS AND METHODS . 623.2.1 Daphnia magna Culture . 623.2.2 Algae Culture . 633.2.3 Preparation of Microplastics . 633.2.4 Microplastics Uptake . 633.2.5 Microplastic Excretion . 643.2.6 Microplastics Uptake as a Function of Concentration. 643.2.7 Quantification of Uptake and Excretion . 653.2.8 Microplastics Visual Assessment . 653.2.9 Chronic Toxicity Tests – Adults . 653.2.10 Chronic Toxicity Test - Neonates . 663.2.11 Statistical analysis . 663.3 RESULTS . 683.3.1 Uptake of Microplastics . 683.3.2 MPs Excretion . 713.3.3 Uptake as a Function of Concentration. 743.3.4 Adult Mortality Test . 753.3.5 Reproduction Test- Adults . 763.3.6 Mortality Test- Neonates . 773.3.7 Reproduction Test- Neonates . 78Word Template by Friedman & Morgan 20143.3.8 Growth Rate . 79vii
3.4 DISCUSSION . 80CHAPTER 4 UP AND AWAY: ONTOGENIC TRANSFERENCE AS APATHWAY FOR AERIAL DISPERSAL OF MICROPLASTICS. 854.1 ABSTRACT . 864.2 INTRODUCTION . 864.3 MATERIAL AND METHODS . 874.4 RESULTS . 884.5 DISCUSSION . 91CHAPTER 5 EXAMINING EFFECTS OF ONTOGENIC MICROPLASTICTRANSFERENCE ON CULEX MOSQUITO MORTALITY AND ADULTWEIGHT . 935.1 ABSTRACT . 945.2 INTRODUCTION . 945.3 MATERIALS AND METHODS . 975.3.1 Preparation of microplastics (MPs) . 975.3.2 Mosquito colonies . 975.3.3 Experimental protocols. 975.3.4 Uptake and ontogenic transference . 985.3.5 Mortality rates . 985.3.6 Emerging adult weights . 985.3.7 Statistical methods . 995.4 RESULTS . 995.5 DISCUSSION . 103CHAPTER 6 THE FATE AND EFFECT OF 15µM POLYSTYRENEMICROPLASTICS ON A FRESHWATER POND COMMUNITY . 1076.1 INTRODUCTION . 1086.2 MATERIALS AND METHODS . 1106.2.1 Preparation of microplastics . 1106.2.2 Study site and ponds . 1106.2.3 Preparation and sampling of the community ponds . 1126.2.4 Partitioning of microplastics in ponds . 1136.2.5 Statistical analysis . 1146.3 RESULTS . 115viiiWord Template by Friedman & Morgan 20146.3.1 Redundancy analysis on pond community . 115
6.3.2 Effects of microplastics on pond’s community . 1176.3.3 Partitioning of microplastics between the water and sediment . 1266.3.4 External factors . 1276.4 DISCUSSION . 128CHAPTER 7 THE INFLUENCE OF MICROPLASTICS ON TROPHICINTERACTION STRENGTHS AND COLONISATION PREFERENCES OFDIPTERANS . 1317.1 ABSTRACT . 1327.2 INTRODUCTION . 1327.3 MATERIALS AND METHODS . 1347.3.1 Experimental design . 1347.3.2 Data analysis . 1357.4 RESULTS . 1357.5 DISCUSSION . 138CHAPTER 8 SUMMARY AND GENERAL DISCUSSION. 1418.1 GENERAL OVERVIEW. 1418.2 UPTAKE OF MICROPLASTICS BY FRESHWATER INVERTEBRATES . 1428.3 ECOTOXICOLOGICAL EFFECT OF MICROPLASTICS ON FRESHWATER INVERTEBRATES. 1448.4 ALENVIRONMENT . 1458.5 BIOACCUMULATION OF MPS ON THE FOOD CHAIN . 1468.6 CONCLUSION AND FUTURE WORK . 147Word Template by Friedman & Morgan 2014REFERENCES . 149ix
LIST OF TABLESTABLE 1-1 SUMMARY OF SELECTED MARINE MICROPLASTIC ENVIRONMENTAL SAMPLINGSTUDIES, COVERING A RANGE OF MARINE ENVIRONMENTS (WATER, PLUS BENTHICAND SHORE SEDIMENTS IN OCEANS AND SEAS).UNITSPROVIDED AS PUBLISHED INTHE STUDIES. . 8TABLE 1-2 SUMMARYOF SELECTED FRESHWATER MICROPLASTIC ENVIRONMENTALSAMPLING STUDIES, COVERING A RANGE OF FRESHWATER ENVIRONMENTS RIVERS(RIVERINE SHORELINE, SHALLOW WATER AND SEDIMENTS) AND LAKES. SOME UNITESWERE CONVERTED AS PUBLISHED IN (HORTON ET AL., 2017). . 14TABLE 1-3 SUMMARY(SHAPES,OF SELECTED FRESHWATER ORGANISMS EXPOSED TO DIFFERENTSIZES AND TYPES) OFMPS. TOEXAMINE THE UPTAKE, DEPURATION ANDTHE ECOTOXICOLOGICAL EFFECT FOR DIFFERENT EXPOSURE TIME. . 19TABLE 2-1 CONCENTRATIONS (MG L-1) OF MPS AND ALGAE ADDED TO EACH TREATMENTTO STUDY THE UPTAKE OF MICROPLASTICS BY DAPHNIA MAGNA. . 43TABLE 2-2 CONCENTRATIONS (MG L-1) OF MPS AND ALGAE ADDED TO EACH TREATMENTTO STUDY CHRONIC TOXICITY IN DAPHNIA MAGNA. . 45TABLE 2-3 MEAN STANDARD ERROR (S.E.) OF LETHAL TIME (LT10, LT50 AND LT90)OF ADULTDAPHNIAMAGNA EXPOSED TO DIFFERENT CONCENTRATIONS (MGL-1)OFMPS AND ALGAE. 51TABLE 2-4 MEAN NEONATESTANDARD ERROR OF LETHAL TIMEDAPHNIA(LT10, LT50ANDLT90)OFL-1)OFMAGNA EXPOSED TO DIFFERENT CONCENTRATIONS (MGMPS AND ALGAE. 53TABLE 3-1 CONCENTRATIONSOF MICROPLASTICS AND ALGAE ADDED TO EACHTREATMENT TO EVALUATE THE UPTAKE OFMPSBYD.MAGNA AS A FUNCTION OFCONCENTRATION . 64TABLE 3-2 CONCENTRATIONSOFMPS (MPS/ML)AND ALGAE(µL)ADDED TO EACHTREATMENT TO STUDY CHRONIC TOXICITY IN D. MAGNA . 66TABLE 3-3 PAIRWISECOMPARISON BETWEEN ALGAE(LOW)AND OTHER TREATMENTS,USING MEAN DIFFERENCES STANDARD ERROR (SE), DEGREES OF FREEDOM AND THExWord Template by Friedman & Morgan 2014P-VALUE FOR EACH TREATMENT . 76
TABLE 3-4 PAIRWISECOMPARISONS BETWEEN CONTROL ALGAETREATMENTS, MEAN DIFFERENCES STANDARD ERROR(LOW)(SE)AND OTHERAND STATISTICALSIGNIFICANCE AS A P-VALUE. . 78TABLE 3-5 MEANDIFFERENCES STANDARD ERROR AND P-VALUE COMPARISONSBETWEEN CONTROL ALGAE (LOW) AND OTHER TREATMENTS . 79TABLE 6-1 CLASSIFICATION AND NUMBER OF THE SPECIES ADDED TO EACH POND. . 112TABLE 6-2 THEANALYSIS OFDAPHNIAMAGNA (WATER FLEA) ABUNDANCE BETWEENCONTROL PONDS AND PONDS TREATED WITHMPS STANDARD ERROR(SE)PERWEEK. . 118TABLE 6-3THE ANALYSIS OFCULEXPIPIENS(MOSQUITOES)ABUNDANCE BETWEENCONTROL AND MPS STANDARD ERROR (SE) PER WEEK. . 119TABLE 6-4 THEANALYSIS OFCHIRONOMUSPLUMOSUS (NON-BITING MIDGE LARVAE)ABUNDANCE BETWEEN CONTROL AND PONDS TREATED WITHMPS STANDARDERROR (SE) PER WEEK. . 121TABLE 6-5 THEANALYSIS OFPOTAMOPYRGUSANTIPODARUM(JENKINSABUNDANCE BETWEEN CONTROL AND PONDS TREATED WITHSPIRE-SHELL)MPS STANDARDERROR (SE) PER WEEK. . 122TABLE 6-6 THEANALYSIS OFHYDRACHNIDIA (WATERMITE) ABUNDANCE BETWEENCONTROL AND PONDS TREATED WITH MPS STANDARD ERROR (SE) PER WEEK. . 123TABLE 7-1 FIRST ORDER TERMS FROM THE PROPORTION OF PREY KILLED AS A FUNCTIONOF PREY DENSITY ACCORDING TOMPHANDLING TIME PARAMETERS FROMEXPOSURE TREATMENTS.ROGERS’RATE ANDRANDOM PREDATOR EQUATION ANDBOOTSTRAPPED (N 2000) 95% CONFIDENCE INTERVALS (CIS).Word Template by Friedman & Morgan 2014ATTACK. 136xi
LIST OF FIGURESFIGURE 1-1 HYPOTHESIZED (GREY)AND KNOWN (BLACK) SOURCES AND PATHWAYS OFMICROPLASTIC INTO HABITATS. (BROWNE, 2015) . 5FIGURE 1-2 CUMULATIVENUMBER OF PAPERS ON BIOTA INTERACTIONS WITHMICROPLASTICS (LUSHER ET AL., 2017).FIGURE 1-3 SOURCE. 10AND ACCUMULATION OF MICROPLASTICS IN THE MARINEENVIRONMENT (WRIGHT ET AL., 2013). . 12FIGURE 1-4 CYCLICDAPHNIAPARTHENOGENESIS INMAGNA.INDIVIDUALSALTERNATE BETWEEN SEXUAL AND PARTHENOGENETIC DASEXUALEMBRYOSCANWHENFULLYDEVELOP IN THE BROOD CHAMBER OF MATURE FEMALE DAPHNIAS, AND ARE THENDIRECTLY RELEASED IN THE ENVIRONMENT.SEXUAL REPRODUCTION REQUIRES THEPARTHENOGENETIC (CLONAL) PRODUCTION OF MALES THAT THEN MATE WITH ADULTFEMALES TO FERTILIZE ONE TO TWO HAPLOID EGGS THAT ARE ENCAPSULATED IN AHARD SHELL AND CAN UNDERGO A RESTING PHASE KNOWN AS DIAPAUSE(EBERT,2005). DRAWING BY DITA B. VIZOSO, FRIBOURG UNIVERSITY. . 30FIGURE 1-5 THEANATOMY OF ADULT FEMALEDAPHNIAMAGNA SHOW THE DIGESTIVESYSTEM WHICH CONSIST OF THREE PARTS (ESOPHAGUS, MIDGUT, AND HINDGUT) ANDTHE DIGESTIVE CECA (DIVERTICULA) IN THE HEAD SECTION OF THE MIDGUT(EBERT,2005). . 32FIGURE 1-6 CULEXPIPIENS LIFE CYCLE,ADULTS LAY THEIR EGGS ON THE WATERSURFACE, HATCH TO LARVAE STAGE(1ST, 2ND, 3RD AND 4TH INSTARS) TO DEVELOP TOPUPAL STAGE THEN FLYING ADULTS. 34FIGURE 2-1 UPTAKE OF 2 µM POLYSTYRENE MPS BY DAPHNIA MAGNA EXPOSED TO MPSONLY (1.46 102 MG L-1) OR MPS WITH ALGAE (1.46 102 MG L-1 AND 1.00 10-1 MGL-1) OVER 240 MIN. EACH POINT REPRESENTS THE MEAN THE STANDARD ERROR. 47FIGURE 2-2 EXCRETION OF 2 ΜM POLYSTYRENE MPS FROM THE GUT OF DAPHNIA MAGNAEXPOSED TO MPS ONLY (1.46 102 MG L-1) OR MPS WITH ALGAE (1.46 102 MG L-1AND1.00 10 1 MG L-1) OVER 240 MIN. EACH POINT REPRESENTS THE MEAN THExiiWord Template by Friedman & Morgan 2014STANDARD ERROR. . 48
FIGURE 2-3 UPTAKE OF 2 ΜM POLYSTYRENE MPS BY DAPHNIA MAGNA WITH AND WITHOUTALGAE IN VARIOUS VOLUMES (ΜL) (SEETABLE 2.1 FOR ACTUAL CONCENTRATIONS).EACH POINT REPRESENTS THE MEAN THE STANDARD ERROR. . 49FIGURE 2-4 MORTALITY OF DAPHNIA MAGNA EXPRESSED AS A FUNCTION OF TIME AFTERCHRONIC EXPOSURE TO MPS UNDER HIGH AND LOW FOOD CONDITIONS FOR 21 DAYS.ASTERISKS DENOTE OVERLAP BETWEEN TWO TREATMENTS. . 50FIGURE 2-5 EFFECTSMPSOF COMBINATIONS OF HIGH AND LOWAND ALGAECONCENTRATIONS ON THE MEAN NUMBER OF OFFSPRING ON DAPHNIA MAGNA. ERRORBARSINDICATE T DIFFERENCES COMPARED TO THE CONTROL P 0.001. . 52FIGURE 2-6 MORTALITYTREATMENTS OFOF NEONATEMPSAND ALGAE OVERBETWEEN TWO TREATMENTS.FIGURE 2-7 DAPHNIADAPHNIAMAGNA AFTER EXPOSURE TO DIFFERENT21DAYS.ASTERISKSDENOTE OVERLAP. 53MAGNA REPRODUCTION (NEONATE PRODUCTION) AFTEREXPOSURES TO A RANGE OFMP21DAYS’AND ALGAE TREATMENTS (ALGAE (LOW), ALGAE(HIGH), ALGAE MP(LOW), ALGAE MP(HIGH), ALGAE MP, MP ALGAE).ERRORBARS INDICATE 95%CONFIDENCE INTERVALS AND ASTERISKS DENOTESIGNIFICANT DIFFERENCES COMPARED TO THE CONTROL P 0.001. 54FIGURE 2-8 EFFECT OF 21 DAYS’ EXPOSURE TO DIFFERENT COMBINATIONS OF MPS ANDALGAE(ALGAE (LOW),ALGAE (HIGH),ALGAE MP, MP ALGAE)ALGAE MP(LOW), ALGAE MP(HIGH),ON BODY LENGTH OFDAPHNIAMAGNA.EACHPOINTREPRESENTS THE MEAN OF FIVE REPLICATES STANDARD ERROR. . 55FIGURE 3-1 UPTAKE OF 15 µM POLYSTYRENE MPS BY DAPHNIA MAGNA EXPOSED TO MPSONLY(200 MPS100µL-1)OVERML-1) OR240MIN.MPSEACHPLUS ALGAE(200 MPSML-1 WITHPOINT REPRESENTS THE MEAN 7X104CELLSTHE STANDARDERROR (SE). . 68FIGURE 3-2 UPTAKE OF POLYSTYRENE MPS SIZE 15 µM BY UNFED DAPHNIA MAGNA AS AFUNCTION OF TIME;(A)UPTAKE AFTER30MIN,(B)AFTER60MIN,(C)AFTER120MIN AND (D) AFTER 240 MIN ( E) CONTROL D. MAGNA UNDER A TRANSMISSION LIGHTMICROSCOPE. . 69FIGURE 3-3 UPTAKEOF POLYSTYRENEMPSSIZE15µM BYDAPHNIAMAGNA IN THEWord Template by Friedman & Morgan 2014PRESENCE OF ALGAE AS A FUNCTION OF TIME; (A) UPTAKE AFTER 30 MIN, (B) AFTERxiii
60 MIN, (C) AFTER 120 MIN AND (D) AFTER 240 MIN (E) CONTROL D. MAGNA UNDERTRANSMISSION LIGHT MICROSCOPE. 70FIGURE 3-4 MEANNUMBER( SE) 15MAGNA OVER TIME FOLLOWINGWITH ALGAE((200 MPSµM POLYSTYRENEMPSDETECTED INDAPHNIA60 MIN EXPOSURE TO MPS (200 MPS ML-1) OR MPSML-1 AND7X104CELLS100µL-1)WITH SUBSEQUENTTRANSFER ON TO CLEAN MEDIA . 71FIGURE 3-5 DEPURATION OF POLYSTYRENE MICROPLASTICS 15 µM IN SIZE BY D. MAGNA INTHE PRESENCE OF ALGAE AS A FUNCTION OF TIME;MIN,(C)AFTER120MIN AND(D)AFTER240MIN(A) AFTER 30 MIN, (B) AFTER 60(E)CONTROLD.MAGNA UNDERTRANSMISSION LIGHT. 72FIGURE 3-6 DEPURATION OF POLYSTYRENE MICROPLASTICS 15 µM IN SIZE BY NON-FED D.MAGNA AS A FUNCTION OF TIME; (A) AFTER 30 MIN, (B) AFTER 60 MIN, (C) AFTER 120MIN AND (D) AFTER 240 MIN (E) CONTROL D. MAGNA UNDER TRANSMISSION LIGHT 73FIGURE 3-7 THE MEAN ( SE) NUMBER OF 15ΜM POLYSTYRENE MPS IN DAPHNIA MAGNAADULTS EXPOSED TO VARIOUS CONCENTRATIONS OF MP AND ALGAE (SEE TABLE 3.2FOR DETAILS). . 74FIGURE 3-8 MORTALITY OF DAPHNIA MAGNA FOR 21 DAYS EXPRESSED AS A FUNCTION OFTIME AFTER CHRONIC EXPOSURE TOMPS UNDER HIGH AND LOW FOOD CONDITIONS. 75FIGURE 3-9 EFFECTSOF COMBINATIONS OF HIGH AND LOWMPSDAPHNIAMAGNABARS INDICATE 95%CONCENTRATIONS ON THE MEAN NUMBER OF OFFSPRING OFCOMPARE IT TO THE CONTROLALGAE(LOW). ERRORAND ALGAECONFIDENCE INTERVALS. . 76FIGURE 3-10 MORTALITYRATE OVER21DAYS FOR NEONATEDAPHNIAMAGNA AFTEREXPOSURE TO DIFFERENT TREATMENTS OF MPS AND ALGAE . 77FIGURE 3-11 EFFECTSOF COMBINATIONS OF HIGH AND LOWMPSDAPHNIAMAGNABARS INDICATE 95%CONCENTRATIONS ON THE MEAN NUMBER OF OFFSPRING OFCOMPARE IT TO THE CONTROLALGAE(LOW). ERRORAND ALGAECONFIDENCE INTERVALS. . 78FIGURE 3-12 EFFECT OF 21 DAYS EXPOSURE TO DIFFERENT COMBINATIONS OF MPS ANDxiv(ALGAE (LOW), ALGAE (HIGH), ALGAE MP(LOW), ALGAE MP(HIGH),Word Template by Friedman & Morgan 2014ALGAE
ALGAE
quantified and there is a paucity of information on the impacts of MPs in freshwater ecosystems, despite the broad range of pathways through which MPs can proliferate and . fate and ecotoxicological impact of MPs on freshwater invertebrates. Initially, MP uptake and chronic toxicity tests were gathered by exposing the crustacean water flea .
May 02, 2018 · D. Program Evaluation ͟The organization has provided a description of the framework for how each program will be evaluated. The framework should include all the elements below: ͟The evaluation methods are cost-effective for the organization ͟Quantitative and qualitative data is being collected (at Basics tier, data collection must have begun)
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