M.Sc. / The occurrence of invertebrates in drinking water supplies is a common consumer complaint with studies showing that very few drinking water distribution networks are totally free of organisms. A detailed investigation of different types of metazoan animals in the drinking water supply networks of South Africa has not been undertaken. In limited worldwide studies, invertebrates (mainly Amphipoda, Chironomidae, Cladocera, Copepoda and Ostracoda) have been detected in produced drinking water. In countries that have started monitoring these organisms, the quality of the produced water has improved due to the improved methods of filtering. The occurrence of “worms” (Nematodes and Diptera) and Crustaceans decreases the aesthetic value of the drinking water, and pathogenic organisms, which may also be associated with them, can affect human health. Limited reference works have been compiled during the conducted studies on drinking water distribution networks throughout the world. All fresh water invertebrates have the potential to be passed into the drinking water supply network (Rising mains, pipelines, reservoirs, and consumer taps). There are few complete reference works available for fresh water invertebrates occurring in the fresh water sources and those of Southern Africa. Therefore, there are no reference works regarding fresh water invertebrates that can be used to monitor drinking water supply networks in South Africa. / Prof. J.H.J. van Vuren

This research investigated the impact of invertebrates to four species of native aquatic macrophytes: V. americana, P. nodosus, P. illinoensis, and N. mexicana. Two treatments were utilized on each plant species, an insecticide treatment to remove most invertebrates and a non-treated control. Ten herbivore taxa were collected during the duration of the study including; Synclita, Paraponyx, Donacia, Rhopalosiphum, and Hydrellia. Macrophyte biomass differences between treatments were not measured for V. americana or N. mexicana. The biomasses of P. nodosus and P. illinoensis in non-treated areas were reduced by 40% and 63% respectively. This indicated that herbivory, once thought to be insignificant to aquatic macrophytes, can cause substantial reductions in biomass.

Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2017-07-14T13:25:17Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Dissertacao com as correcoes da banca-2.pdf: 7763298 bytes, checksum: 36272e73c79d4926dc5e8ecb3b84eb35 (MD5) / Made available in DSpace on 2017-07-14T13:25:17Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Dissertacao com as correcoes da banca-2.pdf: 7763298 bytes, checksum: 36272e73c79d4926dc5e8ecb3b84eb35 (MD5) Previous issue date: 2016-02-26 / FACEPE / Invertebrados terrestres podem ser empregados como biomonitores para a avaliação da qualidade ambiental de áreas urbanas devido à capacidade de absorver substâncias químicas do ambiente por meio da alimentação ou contato direto. Ainda são poucos os estudos realizados utilizando insetos como biomonitores, mesmo sendo bastante relevantes ao considerar seu papel ecológico e densidade populacional elevada. Este trabalho foi realizado com o intuito de utilizar invertebrados terrestres como biomonitores nas áreas urbanas Manguezal Memorial Arcoverde, Reserva da Mata do Frio e Campus Tecnológico do Nordeste, todas localizadas em Pernambuco. Para fins de monitoração de impactos ambientais, foram utilizados padrões de referência para estudos ambientais da classe Insecta obtidos no Refúgio Ecológico Charles Darwin, Igarassu, Pernambuco, unidade conservação com maior grau de conservação. A coleta dos invertebrados para realização do estudo foi executada utilizando-se armadilhas com iscas de mel, laranja, sardinha e carne putrefata a fim de atrair animais com diferentes hábitos alimentares. Após a coleta, os invertebrados foram lavados e em seguida, separados em nível de ordem para realização das análises químicas. A maior diversidade de ordens de invertebrados terrestres foi encontrada na Reserva da Mata do Frio, enquanto a ordem mais abundante coletada nas áreas urbanas estudadas foi Hymenoptera. Porções-teste de 0,1 g de massa seca foram analisadas por Espectrometria de Fluorescência de Raios-X por Dispersão de Energia (EDXRF), Espectrometria de Massas com Plasma Indutivamente Acoplado (ICP-MS) e Absorção Atômica por Forno de Grafite (GFAAS). A qualidade do procedimento analítico foi avaliada utilizando-se de porções-teste dos materiais de referência SRM 2976, SRM 8414, SRM 8415 e IAEA 336. As técnicas analíticas empregadas permitiram a determinação da concentração dos elementos químicos As, Cd, Cl, Co, Cr, Cu, Fe, K, Mo, P, Pb, S, Sb, Th, U e Zn nos invertebrados das áreas urbanas estudadas. O manguezal Parque Memorial Arcoverde apresentou maiores características de ambiente impactado, devido às elevadas concentrações de Cd, Co, Cu, Mo, S, Sb e Zn nos invertebrados analisados. Na Reserva da Mata do Frio, foram obtidas concentrações superiores dos elementos químicos Cl, Cu, K e Zn, enquanto que, no Campus Tecnológico do Nordeste, o elemento químico Cd se destacou por apresentar concentração superior a faixa esperada em amostras de Hymenoptera. Considerando a relativa facilidade de coleta e análise, diversos ecossistemas puderam ser avaliados convenientemente utilizando invertebrados terrestres. / Terrestrial invertebrates can be employed as biomonitors for the environmental quality assessment in urban areas due to the ability of uptake of chemical substances through food or direct contact. Moreover, there are few studies using insects as biomonitors, even though their relevance owing to their ecological role and high population density. This work has utilized terrestrial invertebrates as biomonitors in the urban areas Parque Memorial Arcoverde, Reserva da Mata do Frio and Campus Tecnológico do Nordeste, located in the Pernambuco State, Brazil. Reference standards for environmental studies of class Insecta obtained in the Refúgio Ecológico Charles Darwin, Igarassu, Pernambuco, Brazil, a conservation unit of high conservation level, were used for environmental impact monitoring purposes. Invertebrates were sampled by using traps with honey, orange, sardine and rotten meat as attractive for animals of different food habits. After, the invertebrates were washed and then separated at the order level in order to analyze the chemical elements. The greatest diversity of orders was found in the Reserva da Mata do Frio, while the most abundant order in the studied urban areas was Hymenoptera. Test portions of 0.1 g were analyzed by Energy Dispersive X-Ray Fluorescence Spectroscopy (EDXRF), Inductively Coupled Plasma Mass Spectrometry (ICPMS) and Graphite Furnace Atomic Absorption (GFAAS). The quality of the analytical procedure was evaluated using the reference materials SRM 2976, SRM 8414, 8415 and IAEA 336. The analytical techniques employed here allowed the determination of As, Cd, Cl, Co, Cr, Cu, Fe, K, Mo, P, Pb, S, Sb, Th, U and Zn in the invertebrates from the studied urban areas. The Parque Memorial Arcoverde mangrove was considered one of the most impacted areas according to the high concentrations of Co, Cu, Mo, S, Sb and Zn determined in the invertebrates. For the Reserva Mata do Frio, it was observed the highest concentrations of the chemical elements Cl, Cu, K and Zn, while one invertebrate sample from the Campus Tecnológico do Nordeste accumulated Cd above the expected range. Considering the relative facility of sampling and analysis, diverse ecosystems could be appropriately assessed by means of terrestrial invertebrates.

O gênero Plesiopelma Pocock, 1901 é revisado taxonomicamente e realizada análise cladística de suas espécies. A matriz com 30 táxons terminais e 49 caracteres foi analisada com dois programas para reconstrução filogenética, considerando tanto caracteres aditivos como não-aditivos. As quatro análises apresentaram diferenças na topologia, porém três delas demonstram que Plesiopelma é um gênero monofilético. A diagnose e a distribuição geográfica das espécies são apresentadas. São consideradas válidas as espécies P. flavohirtum (Simon, 1889), P. semiaurantiacum (Simon, 1897),P. myodes Pocock, 1901, P. insulare (Mello-Leitão, 1923), P. physopus (Mello-Leitão, 1926), P. minense (Mello-Leitão, 1943) e P. simoni (Soares e Camargo, 1948). É proposta a sinonímia de P. rectimanum (Mello-Leitão, 1923) e P. longisternale (Schiapelli e Gerschman, 1942) com P. myodes. São reconhecidas seis espécies novas para o Brasil. É proposta a transferência de P. imperatrix Piza, 1976 para o gênero Megaphobema Pocock, 1901 e P. gertschi (Caporiacco, 1955) é considerada Incertae sedis. / The genus Plesiopelma Pocock, 1901 is taxonomically revised and a cladistic analysis of its species is done. The matrix with 30 terminal taxa and 49 characters was analysed with two programs for phylogenetic reconstruction. The four analyses showed different topologies on the internal group, however, three of them show Plesiopelma being a monophyletic genus. The diagnoses and geographic distribution of all species are presented. It is herein considered valid the species P. flavohirtum (Simon, 1889), P. semiaurantiacum (Simon, 1897), P. myodes Pocock, 1901, P. insulare (Mello-Leitão, 1923), P. physopus (Mello-Leitão, 1926), P. minense (Mello-Leitão, 1943) and P. simoni (Soares e Camargo, 1948). The species P. rectimanum (Mello-Leitão, 1923) and P. longisternale (Schiapelli & Gerschman, 1942) are considered junior-synonyms of P. myodes. It is recognized six new species from Brazil. It is proposed the transfer of P. imperatrix Piza, 1976 to Megaphobema Pocock, 1901 and P. gertschi (Caporiacco, 1955) is considered Incertae sedis.

In boreal forest streams, woody debris is an important habitat component. Stream invertebrates and salmonids such as brown trout benefit from in-stream wood. The studies presented in this thesis explore how drifting stream invertebrates respond to addition of fine woody debris, and how young-of-the-year (0+) brown trout behave in habitats with and without fine woody debris. The first paper reports results from a field experiment where fine woody debris was added to streams, and invertebrate drift was measured in order to detect impacts of the fine woody debris on drift density, biomass and taxon diversity. In the end of the season, the fine woody debris-affected drift samples showed higher density, biomass and taxon diversity than the control samples. In the second paper, I describe effects of fine woody debris on 0+ brown trout, studied in laboratory stream channels. Trout were tested in habitats without fine woody debris, with an intermediate fine woody debris density, and with a high fine woody debris density. Swimming activity and foraging time were significantly lower when fine woody debris was present than when it was absent. More time was spent sheltering at the high fine woody debris density than at the intermediate one. The increasing exploitation of fine woody debris for biofuel purposes should be considered in relation to the effects on brown trout and stream invertebrate habitat. / <p>Artikel 1 ingick i avhandlingen som manuskript med titeln "Effects of fine wood addition on invertebrate drift in boreal forest streams". Nu publicerad.</p>

Human activities are increasing the size, frequency and severity of disturbance across earth’s ecosystems including deserts. Exotic annual grasses have altered fire regimes by increasing the size, frequency, and severity of fires in these systems. Invertebrates make up a large proportion of ecosystem diversity, provide a wide range of ecosystem functions, and are good indicators of ecosystem function and resilience. Ants are particularly good indicators of ecosystem stability. The ability of rodents to modify plant community structure post-fire, could result in rodent communities having important indirect effects on invertebrate communities. In chapter 1 we report changes in ant forager abundance and diversity with fire and rodent treatments over a three year period in the Great Basin. We found that while rodents had significant effects on the plant community in burned plots, this did not affect the ant community. Fire, however played a significant role in determining ant species richness and Shannon’s diversity index. Ant richness and diversity were reduced in burned areas compared to unburned areas. Total ant forager abundance was unaffected by fire, however, the abundance of the most common ant species, Pogonomyrmex occidentalis, increased in burned areas. The overall abundance of the other species was reduced in burned areas. We saw increases in the densities of P. occidentalis mounds in burned areas, but the average size of those discs decreased. The total area occupied by P. occidentalis mounds remained equal between burned and unburned plots. In chapter 2 we compare the abundances of different groups of invertebrates, as well as the abundances and diversity of the ant communities, between fire and rodent treatments. We then compared how those responses differed between sites in the Great Basin and Mojave deserts. In this study, we found that the abundances of most invertebrate groups remained unaffected by fire and rodent treatments. In the Great Basin, however, the abundance of flying-foragers was reduced in burned areas. At both locations, ant species richness and Shannon’s diversity were reduced in burned areas. Species richness and Shannon’s diversity were negatively correlated with invasive plant cover at both sites, and invasive plant cover was positively correlated with fire. The loss of diversity can spell losses in important ecosystem functions, and invasive grass fire cycles threaten to make these losses permanent.

Without an adequate understanding of complex interactions between native and non-native species, management of invasive species can result in unforeseen detrimental impacts. I used both field and laboratory experiments to study reciprocal species interactions between the endangered Mohave tui chub (Siphateles bicolor mohavensis) and invasive western mosquitofish (Gambusia affinis). I also examined the impacts of both fish species on the aquatic invertebrate communities in desert springs. I demonstrate a case of intraguild predation (IGP) as a mechanism facilitating co-persistence of the endangered Mohave tui chub with invasive mosquitofish using field mesocosm experiments. In this case of IGP, adult tui chub prey on adult and juvenile mosquitofish, while adult mosquitofish prey on tui chub eggs and/or larvae. I conducted laboratory predation trials to assess if IGP was size-structured due to predator gape-limitation. I explored sex specific differences in gape-size limitation in mosquitofish, because mosquitofish are sexually dimorphic. Larval tui chubs had lower survival in the presence of female mosquitofish than in the presence of males. Reciprocally, male mosquitofish had lower survival than the females in the presence of Mohave tui chub. These results combined with vulnerability modeling supported that IGP in this system is size structured based on gape-size limitation. These results collectively suggest size-structured IGP may facilitate the co-persistence of these two fish species. My findings also suggest that mosquitofish may not be a limiting factor for the persistence of the endangered Mohave tui chub. Further, habitats currently harboring mosquitofish were considered as future refuge habitats for Mohave tui chub, a management option previously un-available. In addition to such reciprocal interactions between fish species, recently established fish populations may impact unique invertebrate communities. Mesocosm experiments with sympatric and allopatric populations of tui chub and mosquitofish showed negative impacts of both fish species on changes of invertebrate community structure. Specifically, fish caused population declines and, in some cases, extirpations of various invertebrate taxa. These results suggest important conservation implications of invasive fish as well as protected fish transplants into fishless desert springs. Overall my research emphasizes the complexity of ecological interactions between native and non-native fish species in desert aquatic systems.

Das Verständnis über die Ausprägung der Lebensgemeinschaften von benthischen Invertebraten in aquatischen Ökosystemen in Abhängigkeit von abiotischen Faktoren ist von grundlegender wissenschaftlicher Bedeutung und eine Voraussetzung für die Bewertung, den Schutz und die Wiederherstellung der ökologischen Integrität in Fließgewässern. Für die Erarbeitung von Abhängigkeiten zwischen der benthischen Lebensgemeinschaft, der Hydromorphologie und der Saprobie standen insgesamt 409 Datensätze in Form von Taxalisten des Makrozoobenthos zur Verfügung. Diese wurden mit Strukturgütedaten verschnitten und anhand uni- und multivariater statistischer Methoden analysiert. Folgende Ergebnisse konnten dabei erzielt werden: (a) es können sieben Einzelparameter der Gewässerstruktur identifiziert werden, die einen signifikanten Einfluss auf die benthische Biozönose ausüben, (b) die Fließgewässertypen 5 und 5.1 unterscheiden sich auf Basis des vorliegenden Datensatzes weder in der taxonomischen noch in der funktionalen Zusammensetzung der Makrozoobenthoszönose und (c) bei einer erhöhten saprobiellen Belastung überlagert der Einfluss der organischen Belastung die strukturellen Gegebenheiten. Für die Entwicklung und Anpassung effizienter Strukturgüteverfahren und die daraus resultierenden Monitoring- und Maßnahmenprogramme für ein integriertes Fließgewässermanagement ist die Auswahl ökologisch relevanter Parameter von immenser Bedeutung. / The understanding about the development of benthic invertebrate communities as a function of abiotic influencing factors in aquatic ecosystems is of essential scientific relevance for the assessment of the ecological status of rivers and streams. For the development of interdependencies between benthic invertebrates, hydromorphology and saprobity, 409 species lists of the macroinvertebrates were provided. They were aggregated with morphological features and analysed with different uni- and multivariate statistical methods. On the basis of the used analyses, the following results were achieved: (a) seven ecological relevant morphological features with significant influence to benthic invertebrate community could be identified, (b) on the basis of the present database, the structural and functional composition of the benthic invertebrates can not be differ river type specific (type 5 and 5.1) and (c) if the saprobic pressure decrease, the organic pressure superpose the hydromorphology. The values of the biological attributes are low in spite of near natural morphological conditions. For an ecological efficiency stream habitat assessment, the identified relevant morphological parameters have to consider. The “morphological characteristic curves” are well describing the results of a local monitoring. This application-oriented instrument can be used for (a) the operationalisation of environmental objectives, (b) the development and adaption of monitoring strategies and (c) the derivation and prioritisation of ecological and economic efficiency measurements for an integrated river management.

The leakages of metals from acid sulfate soils and their potential toxicity to benthic invertebrates were studied in the sediment profiles of Lillkvasjön and Lövselefjärden - a lake and an estuary known to be affected by acid sulfate soils - in Västerbotten, northern Sweden. The concentrations of 25 different elements were analyzed throughout both sediment profiles through X-Ray Fluorescence (XRF) Spectrometer analysis. Organic matter was measured through loss-on-ignition (LOI). By performing correlation analysis and normalizations to LOI on all sediment variables, Cu, Fe, Ni, Pb, S and Zn were found to be leached from acid sulfate soils to both sites, while Mg and Mn were related to leakages from acid sulfate soils in Lövselefjärden. The concentrations of Cu (195 mg kg-1), Ni (55 mg kg-1), Pb (90 mg kg-1) and Zn (398 mg kg-1) in the surface sediment of Lövselefjärden were classified as potentially toxic to benthic invertebrates. In Lillkvasjön, Cu (210 mg kg-1) and Ni (87 mg kg-1) were classified to have an increased risk of negative impacts on benthic invertebrates, while the concentrations of Pb (121 mg kg-1) and Zn (329 mg kg-1) were likely to low to have any negative effects. These results strengthen previous finds of impacts from acid sulfate soils in the two catchment areas and elucidate the importance of further studies on the impact of acid sulfate soils on benthic invertebrates.

Microplastic particles (MPs) are widely distributed in aquatic environments and present a potential risk to marine life. This thesis considers several issues relating to methodologies for sampling and analyzing MPs and the sources and fate of these particles in the marine environment, wild and farmed shellfish, and food webs of southern coastal British Columbia, Canada. Chapter 1 introduces MPs as a contaminant, methodologies for studying them, and reviews what is known about their source, fates, and ecotoxicology in marine environments. Chapter 1 also outlines the goals of this thesis. Chapter 2 compares the potential MP concentration estimates provided by two different seawater sampling methods. Jar samples filtered to 8-µm yielded MP concentrations averaging approximately 8.5 times higher than bucket samples filtered to 63 µm, per L of water (at the site level), driven largely by differences in the number of microfibres. An analysis of MP concentrations and mesh sizes reported in the literature suggests that using a 300–350-µm mesh may underestimate total MP concentrations by one to four orders of magnitude compared with samples filtered through much smaller mesh sizes (e.g., less than 100 µm), and despite the effect of sample volume. Particles less than 300 µm in diameter make up a large component of MPs commonly found in fish and invertebrates. As such, common sampling practices fail to adequately measure a biologically relevant class of MPs, thereby undermining the ability to quantify ecological risk. Chapter 3 determines the influence of shellfish aquaculture activity, and its use of plastic equipment, on MPs in bivalves and their environment by comparing MP concentrations in Manila clams (Venerupis philippinarum) and Pacific oysters (Crassostrea gigas) grown on commercial shellfish beaches with those grown on non-aquaculture beaches from six areas. MP concentrations in water and sediment were also determined in four of the areas. MP concentrations did not differ between shellfish aquaculture and non-aquaculture sites for either bivalve species or for sediment and water samples. Beach sediment type had a minor effect, with more gravelly or sandier beaches associated with higher MP concentrations in oysters or clams, respectively. Oysters on sites using many synthetic anti-predator nets had more MPs than those on sites without any plastic, but analysis of particles using Fourier-transform infrared spectroscopy suggested a predominance of textile fibres including nylon and polyester, which are not typically used in shellfish aquaculture. Chapter 4 uses stable isotope food web analysis and hierarchical Bayesian generalized linear mixed models to explore whether bioaccumulation and biomagnification are occurring in coastal marine food webs at three locations. Bioaccumulation was higher for smaller-bodied suspension feeding animals such as bivalves. However, biomagnification was not occurring in animal digestive tracts, and trophic dilution was demonstrated in fish livers. Trophic transfer was shown to occur between prey and predator for rockfish, but higher concentrations in full stomachs compared with empty ones suggested rapid excretion of ingested MPs. Chapter 5 supplies some general conclusions on the status of MPs in the British Columbian environment, as well as risks to seafood consumers. It also explores future work that will be needed to understand the complex ecotoxicology of MPs. / Graduate / 2022-04-12