Antonia Liess

• PhD
• Professor (Full) at Halmstad University

Climate and land use changes can increase terrestrial runoff to aquatic systems, leading to brownification and eutrophication in northern boreal lakes. Brownification may boost bacterial respiration and production, while eutrophication can enhance primary production and algal blooms. However, their combined effects on basal producers and bacterial...

Wetlands in agricultural areas mitigate eutrophication by intercepting nutrient transports from land to sea. The role of wetlands for nutrient removal may become even more important in the future because of the expected increase in agricultural runoff due to climate change. Because denitrification is temperature dependent, wetland nitrogen (N) remo...

A multitude of anthropogenic pressures deteriorate the Baltic Sea, resulting in the need to protect and restore its marine ecosystem. For an efficient conservation, comprehensive monitoring and assessment of all ecosystem elements is of fundamental importance. The Baltic Marine Environment Protection Commission HELCOM coordinates conservation measu...

Legislations and commitments regulate Baltic Sea status assessments and monitoring. These assessments suffer from monitoring gaps that need prioritization. We used three sources of information; scientific articles, project reports and a stakeholder survey to identify gaps in relation to requirements set by the HELCOM's Baltic Sea Action Plan, the M...

Restored and constructed semi-natural wetlands are increasingly used in the agricultural landscape to intercept nutrients from surface waters. Vegetated surface-flow wetlands remove more nitrogen (N) than those without vegetation. However, changes in N removal over time as differently vegetated wetlands progress from early successional stages to ma...

This survey of 2018 literature on substratum‐associated microbiota presents brief highlights on research findings from primarily freshwaters, but includes those from a variety of aquatic ecosystems. Coverage of topics associated with benthic algae and cyanobacteria, though not comprehensive, includes new methods, taxa new to science, nutrient dynam...

Nutrient optimization has been proposed as a way to increase boreal forest production, and involves chronic additions of liquid fertilizer with amounts of micro- and macro-nutrients adjusted annually to match tree nutritional requirements. We used a short-term (maintained since 2007) and a long-term (maintained since 1987) fertilization experiment...

This review briefly highlights findings from a survey of 2017 literature on substratum-associated microbiota from a variety of aquatic environments, but primarily freshwaters. Centered on algae, cyanobacteria, and bacteria, topics covered include those of relevance to the Water Environment Federation, along with those of recent and emerging interes...

In order to better understand the potential effects of climate change on the Peregrine Falcon, we investigated the relationship between extreme weather events and Peregrines’ breeding success in South Greenland. We defined three variables – number of days with extremely low temperatures, extreme precipitation, consecutive rainy days – and an additi...

• Phosphorus (P) often limits the biomass of primary producers in freshwater lakes. However, in unproductive northern lakes, where anthropogenic nitrogen (N) deposition is low, N instead of P can limit primary producers. In addition, light can be limiting to primary producers at high concentrations of coloured dissolved organic matter (cDOM), as cD...

Setting numeric in-stream objectives (limits, criteria) to inform limits on catchment loads for major landuse stressors is a promising policy instrument to prevent ecosystem degradation. Management objectives can be informed by thresholds identified from stressor - response shapes of ecological indicators based on field survey data. Use of multiple...

The Stream Ecology Research Group at Otago University has won the ”River Story Award” at the 2017 New Zealand River Awards. A 3.5 min video made by the Cawthron Foundation tells a story about the multiple-stressor research done since 2007 in the ExStream System, an innovative research facility delevoped by Jay Piggott and Christoph Matthaei. The vi...

This survey of literature on substratumassociated microbiota from 2016 includes highlights of research findings associated with algae, cyanobacteria, and bacteria from a variety of aquatic environments, but primarily freshwaters. It covers topics of relevance to the Water Environment Federation along with those of emerging or recent interest such a...

Climate change predictions indicate that coastal and estuarine environments will receive increased terrestrial runoff via increased river discharge. This discharge transports allochthonous material, containing bioavailable nutrients and light attenuating matter. Since light and nutrients are important drivers of basal production, their relative and...

This survey of literature on substratum associated microbiota from 2015 highlights research findings associated with benthic algae and bacteria from a variety of aquatic environments, but primarily freshwaters. It focuses on topics of interest to the Water Environment Federation along with those of current emerging interest such as global change, o...

Investigations on organism ecology, biodiversity and biogeography often use large compiled datasets to extract information on species ecological preferences, which then can be used in environmental assessment. Freshwater benthic diatoms are commonly used in this context. However, it is important that the taxonomic information of the separate diatom...

Heavy rainfall events causing significant terrestrial runoff into coastal marine ecosystems are predicted to become more frequent with climate change in the Mediterranean. To simulate the effects of soil runoff on the pelagic food web of an oligotrophic Mediterranean coastal lagoon, we crossed soil extract addition (increasing nutrient availability...

Heavy rainfall events causing significant terrestrial runoff into coastal marine ecosystems are predicted to become more frequent with climate change in the Mediterranean. To simulate the effects of soil runoff on the pelagic food web of an oligotrophic Mediterranean coastal lagoon, we crossed soil extract addition (increasing nutrient availability...

Increased reactive nitrogen (Nr) deposition has raised the amount of N available to organisms and has greatly altered the transfer of energy through food webs, with major consequences for trophic dynamics. The aim of this review is to: 1) clarify the direct and indirect effects of Nr deposition on forest and lake food webs in N limited biomes, 2) c...

This review of literature on substratumassociated microbiota from 2014 highlights topics on benthic algae and bacteria from a range of aquatic environments, but focuses on freshwater habitats. Advances in pollution and toxin detection, assessment methods, and applications of new technologies are highlighted as are updates in taxonomy and systematic...

Endothermic organisms can adapt to short growing seasons, low temperatures and nutrient limitation by developing high growth rates and high gross growth efficiencies ( GGE s). Animals with high GGE s are better at assimilating limiting nutrients and thus should recycle (or lose) fewer nutrients. Longer guts in relation to body mass may facilitate h...

Terrestrial runoff into aquatic ecosystems may have both stimulatory and inhibitory effects, due to nutrient subsidies and increased light attenuation. To disentangle the effects of runoff on microbenthos, we added soil to coastal mesocosms and manipulated substrate depth. To test if fish interacted with runoff effects, we manipulated fish presence...

According to stoichiometric principles, the ratios at which consumers recycle nutrients depend on the elemental compositions of the consumer and its food. However, nutrient assimilation efficiencies and ingestion rates can vary among consumer species and, thus, can affect the rates of consumer-mediated nutrient recycling (CNR). The grazer Theodoxus...

High‐latitude species (and populations within species) are adapted to short and cold summers. They often have high growth and development rates to fully use the short growing season and mature before the onset of winter. Within the context of ecological stoichiometry theory, this study combines ecology with evolution by relating latitudinal life‐hi...

This review of literature published in 2012 covers topics on substratum-associated microbiota (algae and bacteria) from a variety of aquatic environments, especially freshwater ecosystems. It is not a comprehensive review, rather aims to highlight aspects of methods, taxonomy and systematics, ecology, and current environmental issues such as nuisan...

A review of the literature published in 2011 on topics relating to on the subject of ecology of substratum-associated microbiota (algae, bacteria, and fungi). We also highlighted some of the new methods that can be applied to the study of substratum-associated microbiota and included newly described taxa.

Background/Question/Methods High latitude species (and populations within species) are adapted to their unique environment. They often have high growth and development rates to fully utilize the short growing season and mature before winter. Within the concept of ecological stoichiometry theory, this study combines ecology with evolution by relat...

A review of the literature published in 2010 on topics relating to on the subject of ecology of substratum-associated microbiota (algae, bacteria, and fungi). We also highlighted some of the new methods that can be applied to the study of substratum-associated microbiota and included newly described taxa.

Ecological stoichiometry has advanced food web ecology by emphasising the importance of food quality over food quantity for herbivores. Here, we focus on the effects of abiotic factors such as nutrients and light (known to influence food quality) on grazer growth rates. As model organism we used the mudsnail Potamopyrgus antipodarum that is native...

The turnover and distribution of energy and nutrients in food webs is influenced by consumer stoichiometry. Although the stoichiometry of heterotrophs is generally considered to vary only little, there may be intraspecific variation due to factors such as habitat, resources, ontogeny and size. We examined intraspecific variation in Eurasian perch P...

A review of literature on substratrumassociated microbiotia from 2013 covers topics on benthic algae, bacteria and viruses from a range of aquatic environments, but focuses on freshwater ecosystems. Advances in laboratory, field, and assessment methods are highlighted as are updates in taxonomy and systematics. Aspects of water quality, waste-water...

1. Benthic algal communities are shaped by the availability of nutrients and light and by herbivore consumption. Many studies have examined how one of these factors affects algal communities, but studies simultaneously addressing all three are rare. 2. We investigated the effects of nutrients, light and a herbivore (the snail Potamopyrgus antipodar...

1. Neutral community models are derived from the proposition that basic probabilities of species loss (extinction, emigration) and gain (immigration, speciation) explain biological community structure, such that species with many individuals are very likely to be widespread. Niche models on the other hand assume that interactions between species an...

Benthic grazers can affect the nutrient stoichiometry of periphyton through different pathways: 1) grazers can reduce periphyton biomass, thereby increasing the relative amount of nutrients for the remaining periphyton; 2) grazers can change benthic algal community composition toward grazer-resistant taxi that might differ in their C:N:P stoichiome...

1. We tested whether increasing atmospheric nitrogen (N) deposition along a north–south gradient intensifies epilithic phosphorus (P) limitation in oligotrophic Swedish lakes from the north to the south. We examined the epilithic community at a shallow depth from seven northern and six southern Swedish lakes, and also compared the results with a la...

Productivity and grazing pressure interact in determining autotroph diversity, because high productivity increases the capability of a plant community to compensate for grazing losses. However, further factors may play a role in shaping diversity, including primary producer nutrient stoichiometry and grazer activity. Our study focuses on the intera...

Ecological stoichiometry has been successful in enhancing our understanding of trophic interactions between consumer and prey species. Consumer and prey dynamics have been shown to depend on the nutrient composition of the prey relative to the nutrient demand of the consumer. Since most experiments on this topic used a single consumer species, litt...

1. We aimed to separate the effects of grazers on periphyton via grazing from that of nutrient recycling from their faecal pellets. 2. We set up three different experimental treatments (snails/no snails/faecal pellets) and sampled over 16 days. The ‘snail’ treatment contained a low density (snail biomass c. 14 g ⁻² ) of the gastropod grazer Theodox...

The potential interactions of grazing, nutrients and light in influencing autotroph species diversity have not previously been considered. Earlier studies have shown that grazing and nutrients interact in determining autotroph species diversity, since grazing decreases species diversity when nutrients (i.e. N or P) limit autotroph growth, but incre...

Grazer–periphyton interactions are shaped, in part, by indirect effects of nutrient regeneration. They are an important model system with which to test predictions of ecological stoichiometry and the Growth Rate Hypothesis. We conducted a laboratory experiment to test how nutrient enrichment and grazer identity interact to regulate the nutrient con...

We experimentally investigated effects of nutrient enrichment and trophic structure in a microbial food web consisting of mixed bacteria, two bacterivorous ciliates (Tetrahymena sp. and Colpidium sp.) and an omnivorous ciliate (Blepharisma sp.) feeding on both trophic levels. We assembled all possible food webs including one or more of the ciliate...

The stoichiometry of trophic interactions has mainly been studied in simple consumer–prey systems, whereas natural systems often harbour complex food webs with abundant indirect effects. We manipulated the complexity of trophic interactions by using simple laboratory food webs and complex field food webs in enclosures in Lake Erken. In the simple f...

Nutritional constraints on herbivores are important factors structuring food webs. Our study presents field data on the nutrient content of benthic invertebrates from Lake Erken (Sweden). The most abundant benthic invertebrates of the littoral community were sampled in 3 seasons at 5 sites to examine the influence of spatial and temporal variation...

Ecological stoichiometry, the study of the balance of energy and materials in living systems, may serve as a useful synthetic framework for evolutionary biology. Here, we review recent work that illustrates the power of a stoichiometric approach to evolution across multiple scales, and then point to important open questions that may chart the way f...

Ecological stoichiometry describes the biochemical constraints of trophic interactions emerging from the different nutrient content and nutrient demand of producers and consumers, respectively. Most research on this topic originates from well-mixed pelagic food webs, whereas the idea has received far less attention in spatially structured habitats....

In this article we review the indirect interactions prevailing in littoral communities and compare their importance to direct trophic interactions. We focus on the interaction between benthic algae and their herbivorous consumers, i. e. invertebrate grazers and herbivorous fish. In addition to the effects of grazers on periphyton biomass and produc...