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Annette Baattrup-Pedersen

Bio: Annette Baattrup-Pedersen is an academic researcher from Aarhus University. The author has contributed to research in topics: Riparian zone & Macrophyte. The author has an hindex of 23, co-authored 106 publications receiving 1412 citations.


Papers
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TL;DR: A conceptual model has been put forward to describe how aquatic plants respond to eutrophication and the application of the model to management, system remediation, target setting, and the understanding of multi-stressor systems is discussed.
Abstract: Compared to research on eutrophication in lakes, there has been significantly less work carried out on rivers despite the importance of the topic. However, over the last decade, there has been a surge of interest in the response of aquatic plants to eutrophication in rivers. This is an area of applied research and the work has been driven by the widespread nature of the impacts and the significant opportunities for system remediation. A conceptual model has been put forward to describe how aquatic plants respond to eutrophication. Since the model was created, there have been substantial increases in our understanding of a number of the underlying processes. For example, we now know the threshold nutrient concentrations at which nutrients no longer limit algal growth. We also now know that the physical habitat template of rivers is a primary selector of aquatic plant communities. As such, nutrient enrichment impacts on aquatic plant communities are strongly influenced, both directly and indirectly, by physical habitat. A new conceptual model is proposed that incorporates these findings. The application of the model to management, system remediation, target setting, and our understanding of multi-stressor systems is discussed. We also look to the future and the potential for new numerical models to guide management.

93 citations

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TL;DR: The results indicate that macrophytes regulate stream function both via direct uptake of NH4+ from the water column and by providing a substrate for epiphytic biofilms, and the effect of leaf architecture on nutrient uptake rates provides evidence that physical complexity can enhance ecosystem function.
Abstract: Macrophytes act as ecosystem engineers in lowland stream ecosystems, enhancing habitat complexity and physical structure. Studies have demonstrated that macrophyte abundance and growth form can dictate the degree to which physical and biological stream characteristics are altered. However, few studies have investigated the influence of macrophytes and their species-specific variation in morphological complexity on functional processes, such as nutrient uptake. We injected 15N-labeled ammonium (15N-NH4 +) into four macrophyte-rich lowland streams in Denmark to quantify the uptake of NH4 + by macrophytes, epiphytic biofilms, benthic biofilms, and suspended particulate organic matter in the water column. Overall, macrophytes and their epiphytic biofilms accounted for 71–98% of the reach-weighted uptake across the study streams. While macrophytes had the highest rates of NH4 + uptake among the compartments we measured, the epiphytic biofilms had the highest uptake efficiency, ranging from 0.06 to 0.6 mg N mg N biomass −1 d−1. Among all compartments, the uptake efficiency was inversely related to the carbon-to-nitrogen ratio. Macrophyte complexity, expressed as leaf perimeter-to-area ratio (P:A), varied among the five species found in the study streams. The uptake rates by macrophyte species with high leaf P:A were, on average, an order of magnitude higher than the rates for species with simple leaf morphology (430 vs. 49 mg N m−2 d−1). In summary, our results indicate that macrophytes regulate stream function both via direct uptake of NH4 + from the water column and by providing a substrate for epiphytic biofilms. Furthermore, the effect of leaf architecture on nutrient uptake rates provides evidence that physical complexity can enhance ecosystem function.

70 citations

Journal ArticleDOI
TL;DR: This study highlights the potential of traits to capture multiple environmental changes in stream ecosystems and illustrates how organism-specific and highly context-dependent patterns in community organisation can emerge as a consequence of interactions between habitat connectivity and organism dispersal potential.
Abstract: Summary The spatial organisation of biotic communities derives from factors operating at a wide range of spatial and temporal scales. Despite strong scientific evidence of prevalent spatial control of community composition in freshwater ecosystems, local environmental factors are often considered as the main drivers of community change. Furthermore, taxonomic approaches are most frequently used, and few studies have compared the relative importance of local and regional control of trait versus the taxonomic composition in stream ecosystems. Using a spatially dense data set covering all stream sizes in a lowland European region of c. 42 000 km2 and three organism groups (macrophytes, macroinvertebrates and fishes), we compared the relative importance of spatial and environmental determinants of species and trait composition in the study streams, classified into headwaters (stream order 1–2) and downstream sites (stream order >2). We hypothesised that (i) there is a higher correspondence between environmental conditions and trait composition than with species composition, (ii) dispersal limitation (pure spatial structuring) is greater in headwaters than in downstream sites and (iii) dispersal limitation (pure spatial structuring) is weakest for macroinvertebrates, intermediate for macrophytes and strongest for fishes. The most consistent pattern across organisms and stream order groups was a higher correspondence between environmental variation and trait composition as well as a higher number of environmental variables significantly related to trait composition than with species composition (hypothesis 1). Spatial structuring peaked in headwater macrophyte communities and downstream fish communities (hypotheses 2 & 3) – a pattern that was amplified when separate analyses of traits describing species dispersal potential were undertaken. Our study highlights the potential of traits to capture multiple environmental changes in stream ecosystems and illustrates how organism-specific and highly context-dependent patterns in community organisation can emerge as a consequence of interactions between habitat connectivity (i.e. top versus lower parts of the stream network) and organism dispersal potential.

69 citations

Journal ArticleDOI
15 Nov 2019-Science
TL;DR: It is shown, globally, that the frequency of plant species with this trait increases with bicarbonate concentration, and regionally, the frequency is reduced at sites where the CO2 concentration is substantially above the air equilibrium, consistent with this traits being an adaptation to carbon limitation.
Abstract: Unlike in land plants, photosynthesis in many aquatic plants relies on bicarbonate in addition to carbon dioxide (CO2) to compensate for the low diffusivity and potential depletion of CO2 in water. Concentrations of bicarbonate and CO2 vary greatly with catchment geology. In this study, we investigate whether there is a link between these concentrations and the frequency of freshwater plants possessing the bicarbonate use trait. We show, globally, that the frequency of plant species with this trait increases with bicarbonate concentration. Regionally, however, the frequency of bicarbonate use is reduced at sites where the CO2 concentration is substantially above the air equilibrium, consistent with this trait being an adaptation to carbon limitation. Future anthropogenic changes of bicarbonate and CO2 concentrations may alter the species compositions of freshwater plant communities.

69 citations

Journal ArticleDOI
TL;DR: The importance of considering indirect effects of pesticides in the risk assessment of surface water ecosystems is emphasised, as microbial leaf decomposition rates were significantly reduced and the reduction in microbial activity was significantly correlated with loss of microbial biomass (increased C:N ratio).

57 citations


Cited by
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TL;DR: Preface to the Princeton Landmarks in Biology Edition vii Preface xi Symbols used xiii 1.
Abstract: Preface to the Princeton Landmarks in Biology Edition vii Preface xi Symbols Used xiii 1. The Importance of Islands 3 2. Area and Number of Speicies 8 3. Further Explanations of the Area-Diversity Pattern 19 4. The Strategy of Colonization 68 5. Invasibility and the Variable Niche 94 6. Stepping Stones and Biotic Exchange 123 7. Evolutionary Changes Following Colonization 145 8. Prospect 181 Glossary 185 References 193 Index 201

14,171 citations

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TL;DR: The current ecological risk assessment of pesticides falls short of protecting biodiversity, and new approaches linking ecology and ecotoxicology are needed.
Abstract: The biodiversity crisis is one of the greatest challenges facing humanity, but our understanding of the drivers remains limited. Thus, after decades of studies and regulation efforts, it remains unknown whether to what degree and at what concentrations modern agricultural pesticides cause regional-scale species losses. We analyzed the effects of pesticides on the regional taxa richness of stream invertebrates in Europe (Germany and France) and Australia (southern Victoria). Pesticides caused statistically significant effects on both the species and family richness in both regions, with losses in taxa up to 42% of the recorded taxonomic pools. Furthermore, the effects in Europe were detected at concentrations that current legislation considers environmentally protective. Thus, the current ecological risk assessment of pesticides falls short of protecting biodiversity, and new approaches linking ecology and ecotoxicology are needed.

570 citations

Journal ArticleDOI
TL;DR: A review of natural and anthropogenic influences on the distribution and abundance of aquatic plants is presented in this paper, where the authors examine both the direct and indirect influences on aquatic plants.
Abstract: Aquatic plants are important components of many freshwater ecosystems. In this review we examine natural and anthropogenic influences on the distribution and abundance of aquatic plants, and develo...

499 citations