M. Vanni results 29
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Phytoplankton and cyanobacteria abundances in mid‐21st century lakes depend strongly on future land use and climate projectionsNARA Subscribed
Land use and climate change are anticipated to affect phytoplankton of lakes worldwide. The effects will depend on the magnitude of projected land use and climate changes and lake sensitivity to these factors. We used random forests fit with long‐term (1971–2016) phytoplankton and cyanobacteria abundance time series, climate observations (1971–2016), and upstream catchment land use (global Clumondo models for the year 2000) da...
Nitrogen (N) and phosphorus (P) inputs influence algal community structure and function. The rates and ratios of N and P supply, and different N forms (e.g., NO 3 and NH 4 ), from external loading and internal cycling can be highly seasonal. However, the interaction between seasonality in nutrient supply and algal nutrient limitation remains poorly understood. We examined seasonal variation in nutrient limitation and response...
Museum samples could help to reconstruct the original distribution of Salmo trutta complex in ItalyNARA Subscribed
Partial D‐loop sequences of museum specimens of brown trout and marble trout ( Salmo trutta species complex ) collected from Mediterranean rivers in the late 19th century were analysed to help to describe the native distribution of these species. All the individuals studied carried native haplotypes, the geographic distribution of which is consistent with published data. These results indicate that museum specimens from the 19...
Animals can be important in modulating ecosystem‐level nutrient cycling, although their importance varies greatly among species and ecosystems. Nutrient cycling rates of individual animals represent valuable data for testing the predictions of important frameworks such as the Metabolic Theory of Ecology ( MTE ) and ecological stoichiometry ( ES ). They also represent an important set of functional traits that may reflect both...
Climate and land use interactively affect lake phytoplankton nutrient limitation statusNARA Subscribed
Climate‐change models predict more frequent and intense summer droughts for many areas, including the midwestern United States. Precipitation quantity and intensity in turn drive the rates and ratios at which nitrogen (N) and phosphorus (P) are exported from watersheds into lakes, but these rates and ratios are also modulated by watershed land use. This led us to ask the question, is the effect of precipitation on phytoplankto...
Whole‐lake experiments reveal the fate of terrestrial particulate organic carbon in benthic food webs of shallow lakesNARA Subscribed
Lake ecosystems are strongly linked to their terrestrial surroundings by material and energy fluxes across ecosystem boundaries. However, the contribution of terrestrial particulate organic carbon (tPOC) from annual leaf fall to lake food webs has not yet been adequately traced and quantified. In this study, we conducted whole‐lake experiments to trace artificially added tPOC through the food webs of two shallow lakes of simil...
Ecosystem respiration: Drivers of daily variability and background respiration in lakes around the globeNARA Subscribed
We assembled data from a global network of automated lake observatories to test hypotheses regarding the drivers of ecosystem metabolism. We estimated daily rates of respiration and gross primary production (GPP) for up to a full year in each lake, via maximum likelihood fits of a free‐water metabolism model to continuous high‐frequency measurements of dissolved oxygen concentrations. Uncertainties were determined by a bootstr...
Phytoplankton communities and stoichiometry are interactively affected by light, nutrients, and fishNARA Subscribed
We examined the separate and interactive effects of light, nutrients, and zooplanktivorous fish on phytoplankton nutrient stoichiometry, taxonomic richness, community composition, and the associations among these variables. We manipulated light supply, nutrient supply, and zooplanktivorous fish (presence or absence), in a factorial design using mesocosms containing regional phytoplankton and zooplankton assemblages. C : N and...
We explore the role of lakes in carbon cycling and global climate, examine the mechanisms influencing carbon pools and transformations in lakes, and discuss how the metabolism of carbon in the inland waters is likely to change in response to climate. Furthermore, we project changes as global climate change in the abundance and spatial distribution of lakes in the biosphere, and we revise the estimate for the global extent of c...
Detritus, trophic dynamics and biodiversityNARA Subscribed
Traditional approaches to the study of food webs emphasize the transfer of local primary productivity in the form of living plant organic matter across trophic levels. However, dead organic matter, or detritus, a common feature of most ecosystems plays a frequently overlooked role as a dynamic heterogeneous resource and habitat for many species. We develop an integrative framework for understanding the impact of detritus that...
Stoichiometry of nutrient recycling by vertebrates in a tropical stream: linking species identity and ecosystem processesNARA Subscribed
Ecological stoichiometry offers a framework for predicting how animal species vary in recycling nutrients, thus providing a mechanism for how animal species identity mediates ecosystem processes. Here we show that variation in the rates and ratios at which 28 vertebrate species (fish, amphibians) recycled nitrogen (N) and phosphorus (P) in a tropical stream supports stoichiometry theory. Mass‐specific P excretion rate varied 1...