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[EN] Vertical distribution of deep scattering layers (DSL) has been related to dissolved oxygen and illuminance levels as well as to horizontal water mass boundaries. Regional differences have precluded from establishing generic relationships between DSLs vertical distribution and the local hydrographical characteristics. This study used data collected at 18 and 38 kHz (that allow to discriminate between migrant and non-migrant layers) during two surveys carried out in the Canary islands in autumn 2016 and 2017. We evaluated the influence of water masses and their nutrient content, eddies and upwelling areas. While the permanent coastal upwelling increased the scattering of migrant mesopelagic fishes (that are driven through a secondary-order effect by primary production), the non-migrant layers were not affected by it. As in other areas, the main non-migrant acoustic layer (400–600 m depth) was located at horizontal water masses interfaces. The secondary non-migrant DSL, deeper than the main one, was located at depths rich in remineralized nutrients. Eddies modulated the shape of scattering layers into domes (cyclonic) and M-shapes (anticyclonic). This study contributes to a better understanding of how seascape dynamics influence the distribution and shapes of deep scattering layers in the Canary islands.

Many marine planktonic ciliates retain functional chloroplasts from their photosynthetic prey and use them to incorporate inorganic carbon via photosynthesis. While this strategy provides the ciliates with carbon, little is known about their ability to incorporate major dissolved inorganic nutrients, such as nitrogen and phosphorus. Here, we studied how ciliates respond to different concentrations of dissolved inorganic nitrogen and phosphorus. Specifically, we tested the direct and indirect effects of nutrient availability on the ciliate Strombidium cf. basimorphum fed the cryptophyte prey Teleaulax amphioxeia. We assessed responses in the rates of growth, ingestion, photosynthesis, inorganic nutrient uptake, and excretion. Our results show that the prey changed its carbon content depending on the nutrient concentrations. Low inorganic nutrient concentrations increased S. cf. basimorphum growth and prey ingestion. The higher carbon content of the prey under these low nutrient conditions likely supported the growth of the ciliate, while the higher carbon:nutrient stoichiometry of the prey led to the higher ingestion rates. The low carbon content of the prey at high nutrient concentrations resulted in reduced growth of S. cf. basimorphum, which indicates that carbon acquired via photosynthesis in the ciliate cannot compensate for the ingestion of prey with low carbon content. In conclusion, our findings show S. cf. basimorphum is not able to utilize dissolved inorganic nitrogen and phosphorus for growth, and this species seems to be well adapted to exploit its prey when grown at low nutrient conditions.

Many marine planktonic ciliates retain functional chloroplasts from their photosynthetic prey and use them to incorporate inorganic carbon via photosynthesis. While this strategy provides the ciliates with carbon, little is known about their ability to incorporate major dissolved inorganic nutrients, such as nitrogen and phosphorus. Here, we studied how ciliates respond to different concentrations of dissolved inorganic nitrogen and phosphorus. Specifically, we tested the direct and indirect effects of nutrient availability on the ciliate Strombidium cf. basimorphum fed the cryptophyte prey Teleaulax amphioxeia. We assessed responses in the rates of growth, ingestion, photosynthesis, inorganic nutrient uptake, and excretion. Our results show that the prey changed its carbon content depending on the nutrient concentrations. Low inorganic nutrient concentrations increased S. cf. basimorphum growth and prey ingestion. The higher carbon content of the prey under these low nutrient conditions likely supported the growth of the ciliate, while the higher carbon:nutrient stoichiometry of the prey led to the higher ingestion rates. The low carbon content of the prey at high nutrient concentrations resulted in reduced growth of S. cf. basimorphum, which indicates that carbon acquired via photosynthesis in the ciliate cannot compensate for the ingestion of prey with low carbon content. In conclusion, our findings show S. cf. basimorphum is not able to utilize dissolved inorganic nitrogen and phosphorus for growth, and this species seems to be well adapted to exploit its prey when grown at low nutrient conditions.

Many marine planktonic ciliates retain functional chloroplasts from their photosynthetic prey and use them to incorporate inorganic carbon via photosynthesis. While this strategy provides the ciliates with carbon, little is known about their ability to incorporate major dissolved inorganic nutrients, such as nitrogen and phosphorus. Here, we studied how ciliates respond to different concentrations of dissolved inorganic nitrogen and phosphorus. Specifically, we tested the direct and indirect effects of nutrient availability on the ciliate Strombidium cf. basimorphum fed the cryptophyte prey Teleaulax amphioxeia. We assessed responses in the rates of growth, ingestion, photosynthesis, inorganic nutrient uptake, and excretion. Our results show that the prey changed its carbon content depending on the nutrient concentrations. Low inorganic nutrient concentrations increased S. cf. basimorphum growth and prey ingestion. The higher carbon content of the prey under these low nutrient conditions likely supported the growth of the ciliate, while the higher carbon:nutrient stoichiometry of the prey led to the higher ingestion rates. The low carbon content of the prey at high nutrient concentrations resulted in reduced growth of S. cf. basimorphum, which indicates that carbon acquired via photosynthesis in the ciliate cannot compensate for the ingestion of prey with low carbon content. In conclusion, our findings show S. cf. basimorphum is not able to utilize dissolved inorganic nitrogen and phosphorus for growth, and this species seems to be well adapted to exploit its prey when grown at low nutrient conditions.

Many marine planktonic ciliates retain functional chloroplasts from their photosynthetic prey and use them to incorporate inorganic carbon via photosynthesis. While this strategy provides the ciliates with carbon, little is known about their ability to incorporate major dissolved inorganic nutrients, such as nitrogen and phosphorus. Here, we studied how ciliates respond to different concentrations of dissolved inorganic nitrogen and phosphorus. Specifically, we tested the direct and indirect effects of nutrient availability on the ciliate Strombidium cf. basimorphum fed the cryptophyte prey Teleaulax amphioxeia. We assessed responses in the rates of growth, ingestion, photosynthesis, inorganic nutrient uptake, and excretion. Our results show that the prey changed its carbon content depending on the nutrient concentrations. Low inorganic nutrient concentrations increased S. cf. basimorphum growth and prey ingestion. The higher carbon content of the prey under these low nutrient conditions likely supported the growth of the ciliate, while the higher carbon:nutrient stoichiometry of the prey led to the higher ingestion rates. The low carbon content of the prey at high nutrient concentrations resulted in reduced growth of S. cf. basimorphum, which indicates that carbon acquired via photosynthesis in the ciliate cannot compensate for the ingestion of prey with low carbon content. In conclusion, our findings show S. cf. basimorphum is not able to utilize dissolved inorganic nitrogen and phosphorus for growth, and this species seems to be well adapted to exploit its prey when grown at low nutrient conditions.

A portable module has been used to measure inorganic nutrients on the NW coast of the Iberian Peninsula during summer of 2019. The results allow us to know the variability of nutrient concentration and study the potential risk of eutrophication., Peer Reviewed

A portable module has been used to measure inorganic nutrients on the NW coast of the Iberian Peninsula during summer of 2019. The results allow us to know the variability of nutrient concentration and study the potential risk of eutrophication., Peer Reviewed

Eutrophication risk determination requires a continuous acquisition of nutrient data to establish environmental trends. In the context of the MarRISK project, a portable module has been designed to autonomously measure inorganic nutrients together with other parameters such as temperature and salinity along coastal transects

A portable module has been used to measure inorganic nutrients on the NW coast of the Iberian Peninsula during summer of 2019. The results allow us to know the variability of nutrient concentration and study the potential risk of eutrophication

Eutrophication risk determination requires a continuous acquisition of nutrient data to establish environmental trends. In the context of the MarRISK project, a portable module has been designed to autonomously measure inorganic nutrients together with other parameters such as temperature and salinity along coastal transects., Peer Reviewed

Because of its reduced dimensions and its location, surrounded by three continents, the Mediterranean Sea could be especially vulnerable to climate change effects. An increase of the water column stratification could inhibit winter mixing and reduce the frequency and intensity of convection processes which inject nutrients into the photic layer and are responsible for the ventilation of deep waters. In this context, the long-term monitoring of the Mediterranean waters is a basic task. The RADMED project is a monitoring program that covers the waters from the eastern side of the Gibraltar Strait to the Catalan and Balearic Seas. This project was initiated in 2007, merging some previous programs, some of them initiated in 1992. The main objective of this project is to establish average distributions, ranges of variability and long-term trends for physical, and biochemical variables which could be considered as indicative of the environmental state of the sea. The present work analyses nutrient, chlorophyll and oxygen time series from 2007 to 2015 in some cases and from 1992 in other cases. The current analyses show a clear trophic gradient in the RADMED area. Nutrient and chlorophyll concentrations and the intensity of the deep chlorophyll maximum decrease northeastward. The deep chlorophyll maximum depth increases to the northeast. The Balearic and Catalan Seas show a clear seasonal pattern with maximum surface concentrations for nutrients and chlorophyll in winter/spring, associated with winter mixing. On the contrary, the Alboran Sea does not show such a clear seasonal cycle, probably because of the existence of permanent upwelling processes acting along the whole year. The Atlantic Water occupying the upper part of the water column shows a Redfield N:P ratio close to or lower than 16, indicating no phosphorus limitation. Finally, chlorophyll concentrations seem to have increased from 1992 to 2015 in the Alboran Sea, while no longterm changes could be established f

Eutrophication can cause adverse effects in the coastal ecosystems, this leads to an accelerated proliferation of opportunistic microbial and macroalgae communities, altering the trophic structure of the marine ecosystems and deteriorating water quality. Consequently, nutrient enrichment risk negatively affects to ecosystem services (Ferreira et al, 2011; Millennium Ecosystem Assessment, 2005; OSPAR, 2017)

The RETRO-BMC oceanographic cruise was designed to characterize the spatial structures and variability of the Brazil-Malvinas Confluence (BMC) region. The cruise was carried in April 2017 on board the R/V Hespérides, departing from Ushuaia (Argentina) and arriving to Santos (Brazil). There were a total of 33 hydrographic stations, carried out between 13 and 25 April 2017. All stations were offshore from the continental platform and within 42ºS-36ºS and 58ºW-52ºW. Conductivity-temperature-depth (CTD) data were obtained with a SeaBird 911 Plus multi-parametric probe, with redundant salinity and temperature sensors, and additional dissolved oxygen (SBE-43) and fluorescence and turbidity (Wetlabs AFL-NTU-RTD) sensors. Water velocity data was obtained at the stations with a lowered acoustic Doppler current profiler (LADCP) and along the ship’s track with the vessel-mounted ADCP (VADCP). During the entire ship’s track inside the study region, the VADCP gathered velocity data in low-range mode (one velocity profile every 2 min between about 20 and 800 m at 8-m depth bins) and a thermosalinograph gathered salinity and temperature data (every 5 s at a depth of 5 m). The LADCP was attached, together with the CTD, to a 12-liters 24-Niskin-bottle rosette that was used to gather water samples at discrete depths, which were frozen and later analyzed to determine the concentration of inorganic nutrients. In addition, two high-resolution three-dimensional surveys were carried out at the Confluence front with a SeaSoar covering the area between 40.6-39.0°S and 55.6°W-53.8°W. The first transect was completed between the 16 and 17 April, 46 hours covering 620 km, while the second sampled 751 km between the 19 and 21 April 2017, during 52 hours. The SeaSoar was equipped with a SeaBird 911 CTD with the same sensors as in the hydrographic stations, and recorded data in a sawtooth pattern between 5 and 360 m, with a horizontal spacing between apogees of 4 km. Finally, five subsurface drif

Intertidal shellfish banks in estuarine areas are influenced by a wide variety of environmental conditions, including the physical and chemical characteristic of the water that floods the grounds. In this study we carry out a cross-comparison of the hydrographic characteristics and nutrient fertilization patterns of the waters that laps the shellfish grounds of a group of five drowned valleys collectively known as “Rías Altas”, located in the western Cantabrian coast (NW Iberian Peninsula). This region is affected by coastal upwelling from June to August resulting in a water exchange between the embayments and the shelf varying between 31.5 and 220.5 ms. The fresh water discharge followed a seasonal cycle too, with maxima in winter and minima in summer, and long-term average flow rates ranging from 5.9 ms to 22.2 m3 s. Significant differences were observed among the five embayments with regard to temperature and salinity and also with inorganic nutrients, chlorophyll a and particulate organic matter concentrations in the continental waters

Marine picoeukaryotes show high phylogenetic diversity worldwide, notably in oligotrophic waters. In the Gulf of Gabès (south-eastern Mediterranean), characterized by oligotrophic conditions and a complex water mass circulation, information on picoeukaryotic diversity is still lacking. In this study, we investigated the diversity and spatial variability of picoeukaryotic assemblages in relation to nutrient availability, physical parameters and water masses in 3 cruises carried out in the Gulf of Gabès in June of 2008, April of 2009 and November of 2009. High-throughput sequencing revealed a dominance of sequences from non photosynthetic picoeukaryotes, mostly represented by the presumably parasitic marine alveolate MALV-II (33.20%) and the bacterivorous Bicosoecida (13.56%). Differences in picoeukaryotic assemblages were higher between coastal and open-sea stations, and depth in the water column also affected community differences, with surface (5 m), intermediate (25-100 m) and mesopelagic (>200 m) samples forming separate groups. A clear temporal variability was also evident, particularly for communities collected from the surface layer and open-sea stations. Co-inertia analysis revealed that picoeukaryotic groups were more affected by salinity in deep waters, whereas at the surface, they were dependent on nutrients and temperature. During the November cruise, samples that shared similar water mass properties generally clustered together. The Levantine water mass, observed for the first time in this area, was characterized by the presence of Acantharia and Polycystinea. Our study highlights the role of physical and chemical features, such as water mass origin, the wide continental shelf and trophic status, in determining the diversity of marine picoeukaryotes

The oceans absorb about a quarter of the annually produced anthropogenic atmospheric carbon dioxide (CO2), resulting in a decrease in surface water pH, a process termed ocean acidification (OA). Surprisingly little is known about how OA affects the physiology of heterotrophic bacteria or the coupling of heterotrophic bacteria to phytoplankton when nutrients are limited. Previous experiments were, for the most part, undertaken during productive phases or following nutrient additions designed to stimulate algal blooms. Therefore, we performed an in situ large-volume mesocosm (similar to 55 m(3)) experiment in the Baltic Sea by simulating different fugacities of CO2 (fCO(2)) extending from present to future conditions. The study was conducted in July-August after the nominal spring bloom, in order to maintain low-nutrient conditions throughout the experiment. This resulted in phytoplankton communities dominated by small-sized functional groups (picophytoplankton). There was no consistent fCO(2)-induced effect on bacterial protein production (BPP), cell-specific BPP (csBPP) or biovolumes (BVs) of either free-living (FL) or particle-associated (PA) heterotrophic bacteria, when considered as individual components (univariate analyses). Permutational Multivariate Analysis of Variance (PERMANOVA) revealed a significant effect of the fCO(2) treatment on entire assemblages of dissolved and particulate nutrients, metabolic parameters and the bacteria-phytoplankton community. However, distance-based linear modelling only identified fCO(2) as a factor explaining the variability observed amongst the microbial community composition, but not for explaining variability within the metabolic parameters. This suggests that fCO(2) impacts on microbial metabolic parameters occurred indirectly through varying physicochemical parameters and microbial species composition. Cluster analyses examining the co-occurrence of different functional groups of bacteria and phytoplankton further reveal

Marine biogeochemistry dynamics in coastal marine areas is strongly influenced by episodic events such as rain, intense winds, river discharges and anthropogenic activities. We evaluated in this study the importance of these forcing events on modulating seasonal changes in the marine biogeochemistry of the northwestern coast of the Mediterranean Sea, based on data gathered from a fixed coastal sampling station in the area. A 4-year (2011–2014) monthly sampling at four depths (0.5 m, 20 m, 50 m and 80 m) was performed to examine the time variability of several oceanographic variables: seawater temperature, salinity, inorganic nutrient concentrations (NO3−, PO43 − and SiO2), chlorophyll a (Chl a), dissolved organic carbon (DOC) and fluorescent dissolved organic matter (FDOM). FDOM dynamics was predominantly influenced by upwelling events and mixing processes, driven by strong and characteristic wind episodes. SW wind episodes favored the upwelling of deeper and denser waters into the shallower shelf, providing a surplus of autochthonous humic-like material and inorganic nutrients, whereas northerlies favored the homogenization of the whole shelf water column by cooling and evaporation. These different wind-induced processes (deep water intrusion or mixing), reported along the four sampled years, determined a high interannual environmental variability in comparison with other Mediterranean sampling sites.

Marine biogeochemistry dynamics in coastal marine areas is strongly influenced by episodic events such as rain, intense winds, river discharges and anthropogenic activities. We evaluated in this study the importance of these forcing events on modulating seasonal changes in the marine biogeochemistry of the northwestern coast of the Mediterranean Sea, based on data gathered from a fixed coastal sampling station in the area. A 4-year (2011–2014) monthly sampling at four depths (0.5 m, 20 m, 50 m and 80 m) was performed to examine the time variability of several oceanographic variables: seawater temperature, salinity, inorganic nutrient concentrations (NO3−, PO43 − and SiO2), chlorophyll a (Chl a), dissolved organic carbon (DOC) and fluorescent dissolved organic matter (FDOM). FDOM dynamics was predominantly influenced by upwelling events and mixing processes, driven by strong and characteristic wind episodes. SW wind episodes favored the upwelling of deeper and denser waters into the shallower shelf, providing a surplus of autochthonous humic-like material and inorganic nutrients, whereas northerlies favored the homogenization of the whole shelf water column by cooling and evaporation. These different wind-induced processes (deep water intrusion or mixing), reported along the four sampled years, determined a high interannual environmental variability in comparison with other Mediterranean sampling sites

This study originated with the objective of parameterizing riparian evapotranspiration (ET) in the water budget of the Middle Rio Grande. We hypothesized that flooding and invasions of non-native species would strongly impact ecosystem water use. Our objectives were to measure and compare water use of native (Rio Grande cottonwood, Populus deltoides ssp. wizleni) and non-native (saltcedar, Tamarix chinensis, Russian olive, Eleagnus angustifolia) vegetation and to evaluate how water use is affected by climatic variability resulting in high river flows and flooding as well as drought conditions and deep water tables. Eddy covariance flux towers to measure ET and shallow wells to monitor water tables were instrumented in 1999. Active sites in their second decade of monitoring include a xeroriparian, non-flooding salt cedar woodland within Sevilleta National Wildlife Refuge and a dense, monotypic salt cedar stand at Bosque del Apache NWR, which is subject to flood pulses associated with high river flows. These are the meteorological data collected as part of this study.

This study originated with the objective of parameterizing riparian evapotranspiration (ET) in the water budget of the Middle Rio Grande. We hypothesized that flooding and invasions of non-native species would strongly impact ecosystem water use. Our objectives were to measure and compare water use of native (Rio Grande cottonwood, Populus deltoides ssp. wizleni) and non-native (saltcedar, Tamarix chinensis, Russian olive, Eleagnus angustifolia) vegetation and to evaluate how water use is affected by climatic variability resulting in high river flows and flooding as well as drought conditions and deep water tables. Eddy covariance flux towers to measure ET and shallow wells to monitor water tables were instrumented in 1999. Active sites in their second decade of monitoring include a xeroriparian, non-flooding salt cedar woodland within Sevilleta National Wildlife Refuge and a dense, monotypic salt cedar stand at Bosque del Apache NWR, which is subject to flood pulses associated with high river flows. This data set includes the soil temperature and moisture data collected during this study.

Climate models predict that water limited regions around the world will become drier and warmer in the near future, including southwestern North America. We developed a large-scale experimental system that allows testing of the ecosystem impacts of precipitation changes. Four treatments were applied to 1600 m2 plots (40 m × 40 m), each with three replicates in a piñon pine (Pinus edulis) and juniper (Juniper monosperma) ecosystem. These species have extensive root systems, requiring large-scale manipulation to effectively alter soil water availability. Treatments consisted of: 1) irrigation plots that receive supplemental water additions, 2) drought plots that receive 55% of ambient rainfall, 3) cover-control plots that receive ambient precipitation, but allow determination of treatment infrastructure artifacts, and 4) ambient control plots. Our drought structures effectively reduced soil water potential and volumetric water content compared to the ambient, cover-control, and water addition plots. Drought and cover control plots experienced an average increase in maximum soil and air temperature at ground level of 1-4° C during the growing season compared to ambient plots, and concurrent short-term diurnal increases in maximum air temperature were also observed directly above and below plastic structures. Our drought and irrigation treatments significantly influenced tree predawn water potential, sap-flow, and net photosynthesis, with drought treatment trees exhibiting significant decreases in physiological function compared to ambient and irrigated trees. Supplemental irrigation resulted in a significant increase in both plant water potential and xylem sap-flow compared to trees in the other treatments. This experimental design effectively allows manipulation of plant water stress at the ecosystem scale, permits a wide range of drought conditions, and provides prolonged drought conditions comparable to historical droughts in the past – drought events for which wid

Two of the most pervasive human impacts on ecosystems are alteration of global nutrient budgets and changes in the abundance and identity of consumers. Fossil fuel combustion and agricultural fertilization have doubled and quintupled, respectively, global pools of nitrogen and phosphorus relative to pre-industrial levels. In spite of the global impacts of these human activities, there have been no globally coordinated experiments to quantify the general impacts on ecological systems. This experiment seeks to determine how nutrient availability controls plant biomass, diversity, and species composition in a desert grassland. This has important implications for understanding how future atmospheric deposition of nutrients (N, S, Ca, K) might affect community and ecosystem-level responses. This study is part of a larger coordinated research network that includes more than 40 grassland sites around the world. By using a standardized experimental setup that is consistent across all study sites, we are addressing the questions of whether diversity and productivity are co-limited by multiple nutrients and if so, whether these trends are predictable on a global scale.Above-ground net primary production is the change in plant biomass, represented by stems, flowers, fruit and and foliage, over time and incoporates growth as well as loss to death and decomposition. To measure this change the vegetation variables, including species composition and the cover and height of individuals, are sampled twice yearly (spring and fall) at permanent 1m x 1m plots within each site. Volumetric measurements are made using vegetation data from permanent plots (SEV231, "Effects of Multiple Resource Additions on Community and Ecosystem Processes: NutNet NPP Quadrat Sampling") and regressions correlating species biomass and volume constructed using seasonal harvest weights from SEV157, "Net Primary Productivity (NPP) Weight Data."

Historical hydrographic data (1984–2012) from the California Cooperative Oceanic Fisheries Investigations (CalCOFI) program and global reanalysis products were used to quantify recent water mass variability off the coast of Southern California. Dissolved oxygen concentrations continued to decline within the lower pycnocline, concurrent with strong increases in nitrate and phosphate that have spatial patterns matching those of dissolved oxygen. Silicic acid also shows an increasing trend in the offshore portion of the region, but has strong and opposing trends in the upper (increasing) and lower-pycnocline (decreasing) within the Southern California Bight. The varying rates of change in the inorganic nutrients yield a more complex pattern of variability in the nutrient ratios, resulting in large decreases in the N:P and Si:N ratios within the Southern California Bight at depths that provide source waters for upwelling. Basin-scale reanalysis products are consistent with low-frequency water mass changes observed off Southern California and suggest that advection of modified source waters is the cause of the variability. The biogeochemical changes described here may have important impacts on the regional ecosystem, including a reduction of viable pelagic habitat and community reorganization.

We investigated how physical incorporation, brine dynamics and bacterial activity regulate the distribution of inorganic nutrients and dissolved organic carbon (DOC) in artificial sea ice during a 19-day experiment that included periods of both ice growth and decay. The experiment was performed using two series of mesocosms: the first consisted of seawater and the second consisted of seawater enriched with humic-rich river water. We grew ice by freezing the water at an air temperature of -. 14. °C for 14. days after which ice decay was induced by increasing the air temperature to -. 1. °C. Using the ice temperatures and bulk ice salinities, we derived the brine volume fractions, brine salinities and Rayleigh numbers. The temporal evolution of these physical parameters indicates that there was two main stages in the brine dynamics: bottom convection during ice growth, and brine stratification during ice decay. The major findings are: (1) the incorporation of dissolved compounds (nitrate, nitrite, ammonium, phosphate, silicate, and DOC) into the sea ice was not conservative (relative to salinity) during ice growth. Brine convection clearly influenced the incorporation of the dissolved compounds, since the non-conservative behavior of the dissolved compounds was particularly pronounced in the absence of brine convection. (2) Bacterial activity further regulated nutrient availability in the ice: ammonium and nitrite accumulated as a result of remineralization processes, although bacterial production was too low to induce major changes in DOC concentrations. (3) Different forms of DOC have different properties and hence incorporation efficiencies. In particular, the terrestrially-derived DOC from the river water was less efficiently incorporated into sea ice than the DOC in the seawater. Therefore the main factors regulating the distribution of the dissolved compounds within sea ice are clearly a complex interaction of brine dynamics, biological activity and in the case, SCOPUS: ar.j, info:eu-repo/semantics/published

We investigated how physical incorporation, brine dynamics and bacterial activity regulate the distribution of inorganic nutrients and dissolved organic carbon (DOC) in artificial sea ice during a 19-day experiment that included periods of both ice growth and decay. The experiment was performed using two series of mesocosms: the first consisted of seawater and the second consisted of seawater enriched with humic-rich river water. We grew ice by freezing the water at an air temperature of -. 14. °C for 14. days after which ice decay was induced by increasing the air temperature to -. 1. °C. Using the ice temperatures and bulk ice salinities, we derived the brine volume fractions, brine salinities and Rayleigh numbers. The temporal evolution of these physical parameters indicates that there was two main stages in the brine dynamics: bottom convection during ice growth, and brine stratification during ice decay. The major findings are: (1) the incorporation of dissolved compounds (nitrate, nitrite, ammonium, phosphate, silicate, and DOC) into the sea ice was not conservative (relative to salinity) during ice growth. Brine convection clearly influenced the incorporation of the dissolved compounds, since the non-conservative behavior of the dissolved compounds was particularly pronounced in the absence of brine convection. (2) Bacterial activity further regulated nutrient availability in the ice: ammonium and nitrite accumulated as a result of remineralization processes, although bacterial production was too low to induce major changes in DOC concentrations. (3) Different forms of DOC have different properties and hence incorporation efficiencies. In particular, the terrestrially-derived DOC from the river water was less efficiently incorporated into sea ice than the DOC in the seawater. Therefore the main factors regulating the distribution of the dissolved compounds within sea ice are clearly a complex interaction of brine dynamics, biological activity and in the case, SCOPUS: ar.j, info:eu-repo/semantics/published

Climate models predict that water limited regions around the world will become drier and warmer in the near future, including southwestern North America. We developed a large-scale experimental system that allows testing of the ecosystem impacts of precipitation changes. Four treatments were applied to 1600 m2 plots (40 m × 40 m), each with three replicates in a piñon pine (Pinus edulis) and juniper (Juniper monosperma) ecosystem. These species have extensive root systems, requiring large-scale manipulation to effectively alter soil water availability. Treatments consisted of: 1) irrigation plots that receive supplemental water additions, 2) drought plots that receive 55% of ambient rainfall, 3) cover-control plots that receive ambient precipitation, but allow determination of treatment infrastructure artifacts, and 4) ambient control plots. Our drought structures effectively reduced soil water potential and volumetric water content compared to the ambient, cover-control, and water addition plots. Drought and cover control plots experienced an average increase in maximum soil and air temperature at ground level of 1-4° C during the growing season compared to ambient plots, and concurrent short-term diurnal increases in maximum air temperature were also observed directly above and below plastic structures. Our drought and irrigation treatments significantly influenced tree predawn water potential, sap-flow, and net photosynthesis, with drought treatment trees exhibiting significant decreases in physiological function compared to ambient and irrigated trees. Supplemental irrigation resulted in a significant increase in both plant water potential and xylem sap-flow compared to trees in the other treatments. This experimental design effectively allows manipulation of plant water stress at the ecosystem scale, permits a wide range of drought conditions, and provides prolonged drought conditions comparable to historical droughts in the past – drought events for which wi

Mediterranean coastal regions are particularly exposed to oil pollution due to extensive industrialization, urbanization and transport of crude and refined oil to and from refineries. Bioremediation of contaminated beach sand through landfarming is both simple and cost-effective to implement compared to other treatment technologies. The purpose of the present study was to investigate the effect of alternative nutrients on biodegradation of crude oil contaminated beach sand in an effort to reduce the time required for bioremediation employing only indigenous hydrocarbon degraders.A natural sandy soil was collected from Agios Onoufrios beach (Chania, Greece) and was contaminated with weathered crude oil. The indigenous microbial population in the contaminated sand was tested alone (control treatment) or in combination with inorganic nutrients (KNO3 and K2HPO4) to investigate their effects on oil biodegradation rates. In addition, the ability of biosurfactants (rhamnolipids), in the presence of organic nutrients (uric acid and lecithin), to further stimulate biodegradation was investigated in laboratory microcosms over a 45-day period.Biodegradation was tracked by GC/MS analysis of aliphatic and polycyclic aromatic hydrocarbons components and the measured concentrations were corrected for abiotic removal by hopane normalizations. It was found that the saturated fraction of the residual oil is degraded more extensively than the aromatic fraction and the bacterial growth after an incubation period of approximately 3 weeks was much greater from the bacterial growth in the control.The results show that the treatments with inorganic or organic nutrients are equally effective over almost 30 days where C12–C35n-alkanes were degraded more than 97% and polyaromatic hydrocarbons with two or three rings were degraded more than 95% within 45 days. The results clearly show that the addition of nutrients to contaminated beach sand significantly enhanced th

The dynamics of inorganic nutrients and phytoplankton was studied along two transects located in the coastal area of Barcelona (NW Mediterranean), from March 2002 to March 2006. Similar seasonal variability patterns were observed in the four annual cycles and in general, the nutrient concentrations were highest in winter and lowest in summer. Two phytoplankton peaks, composed mainly by diatoms and nanoflagellates, were generally detected during the year with the main peak during winter-early spring, linked to different fertilization mechanisms, and a secondary peak generally found in autumn, probably related both to the new availability of nutrients due to the disruption of the thermocline and to freshwater inputs. During the rest of the year, with a stratified water column and low nutrient concentrations, phytoplankton remained at a low abundance and comprised mainly small dinoflagellates, although there was smaller scale variability conditioned by rainfall events and subsequent freshwater discharges. Despite the similarity of the seasonal patterns, there were interannual changes in origin of new nutrient inputs into the coastal zone and in the taxonomic composition of the winter-early spring phytoplankton maxima. The main source of nutrients for the winter-early spring maxima of 2003 and 2004 was river runoff, while fertilization events in the two following winters were mainly due to the intrusion, onto the Barcelona shelf, of intermediate waters in 2005, and of surface offshore waters, which also carried a different phytoplankton community, in 2006. These changes were linked to unusually cold and dry weather in the winters of 2005 and 2006, which resulted in strong vertical mixing and deep water formation events in the NW Mediterranean basin. The overall amount of nutrients provided to the coastal zone by offshore water fertilization was higher (2005) or equal (2006) than that provided by freshwater inputs in 2003 and 2004. Our findings highlight the importance o

Eleven culture experiments were conducted in the coastal upwelling ­system of the Ría de Vigo (NW Iberian Peninsula) by inoculating GF/C filtrated (10%) in 0.2 µm filtrated (90%) surface seawater collected under contrasting hydrographic conditions. Short-term (4 d) laboratory incubations were performed in the dark at 15°C. Dissolved organic carbon (DOC) concentration, bacterial biomass (BB), bacterial production (BP) and electron transport system (ETS) activity were then monitored to: (1) study the course of bacterial carbon demand (BCD) and growth efficiency (BGE) during the incubation period; and (2) determine how BCD and BGE were linked with changing environmental conditions. Following the 4 d incubation, BP decreased by <4 times its initial values (range from 3 to 11 times) and ETS activity increased by 6 times its initial values (range from 1 to 75 times). As a result, BCD increased by 5 times (range from 1 to 16 times) and the BGE decreased by 15 times (range from 2 to 55 times) over the same period. BGE integrated over the 4 d incubation period ranged from 7 ± 1% to 55 ± 11% (mean ± SD: 27 ± 15%); integrated BGE increased significantly (R2 = 0.64, p < 0.003) with the initial concentration of dissolved inorganic nitrogen (DIN), and decreased significantly (R2 = 0.55, p < 0.01) with the C:N ratio of the bioavailable dissolved organic matter (BDOM). A multiple linear regression with DIN and the C:N ratio of BDOM explained 89% of the observed variability in the integrated BGE, demonstrating the strong dependence of growth efficiency on nutrient conditions and the quality of the organic substrate feeding the community of this coastal embayment.

The US Navy needs to know how distributions and abundances of light-scattering and sound-scattering organisms in the ocean vary in space and time, particularly in the vertical dimension. Recent field observations have shown that many biological properties may vary substantially over small (e.g. centimeter) scales, commonly referred to as thin layers (e.g. Cowles et al. 1998, 1999, Hanson & Donaghay 1998, Holliday et al. 1999, Dekshenieks et al. 2001, Alldredge et al. 2002, Rines et al. 2002). Our previous ONR-funded research has allowed us to begin to understand how zooplankton interact with thin layers and how they can take advantage of biomass of prey concentrated in these small-scale features (Avent et al. 1998, Bollens 2000, Bochdansky & Bollens 2004, Clay et al. 2004, Ignoffo et al., 2005). However, there is almost no information regarding how zooplankton can influence the characteristics and persistence of thin layers. In this project we proposed to address this issue, with two main long-term goals: First, to determine to what extent zooplankton graze and export carbon from thin layers; and second, to determine whether and how zooplankton influence the physical (e.g. optical and acoustical), chemical, and biological characteristics of thin layers with their presence. These goals require determination of rate processes such as feeding activity and excretion, which are very difficult to assess in the field. Thus our research is focused on detailed experimental studies of biological rate processes and behaviors that contribute to the recycling and expert of material in and around thin layers., code 1 only.

The US Navy needs to know how distributions and abundances of light-scattering and sound-scattering organisms in the ocean vary in space and time, particularly in the vertical dimension. Recent field observations have shown that many biological properties may vary substantially over small (e.g. centimeter) scales, commonly referred to as thin layers (e.g. Cowles et al. 1998, 1999, Hanson & Donaghay 1998, Holliday et al. 1999, Dekshenieks et al. 2001, Alldredge et al. 2002, Rines et al. 2002). Our previous ONR-funded research has allowed us to begin to understand how zooplankton interact with thin layers and how they can take advantage of biomass of prey concentrated in these small-scale features (Avent et al. 1998, Bollens 2000, Bochdansky & Bollens 2004, Clay et al. 2004, Ignoffo et al., 2005). However, there is almost no information regarding how zooplankton can influence the characteristics and persistence of thin layers. In this project we proposed to address this issue, with two main long-term goals: First, to determine to what extent zooplankton graze and export carbon from thin layers; and second, to determine whether and how zooplankton influence the physical (e.g. optical and acoustical), chemical, and biological characteristics of thin layers with their presence. These goals require determination of rate processes such as feeding activity and excretion, which are very difficult to assess in the field. Thus our research is focused on detailed experimental studies of biological rate processes and behaviors that contribute to the recycling and export of material in and around thin layers., code 1 only.

Pyruvate kinase (PK) activity measurements are used to assess the role of carbohydrates in global feeding of mesozooplankton communities inhabiting an estuary plume. As a consequence of a remarkably low freshwater discharge rate, the sea surface layers of the area under estuarine influence showed a very moderate salinity fall and a nearly total depletion in nitrates, whereas higher levels of these nutrients were found in deeper, more saline, layers. Small-scale PK activity variations in mesozooplankton appear to be closely correlated to nitrate integration values within the water column. The results were analysed in comparison with literature reports. The study produced a coherent overall interpretation, which strongly supports the reliability of this new biochemical tool in detecting assimilation of trace carbohydrates in the diet of mesozooplankton.

Pyruvate kinase (PK) activity measurements are used to assess the role of carbohydrates in global feeding of mesozooplankton communities inhabiting an estuary plume. As a consequence of a remarkably low freshwater discharge rate, the sea surface layers of the area under estuarine influence showed a very moderate salinity fall and a nearly total depletion in nitrates, whereas higher levels of these nutrients were found in deeper, more saline, layers. Small-scale PK activity variations in mesozooplankton appear to be closely correlated to nitrate integration values within the water column. The results were analysed in comparison with literature reports. The study produced a coherent overall interpretation, which strongly supports the reliability of this new biochemical tool in detecting assimilation of trace carbohydrates in the diet of mesozooplankton.

Pyruvate kinase (PK) activity measurements are used to assess the role of carbohydrates in global feeding of mesozooplankton communities inhabiting an estuary plume. As a consequence of a remarkably low freshwater discharge rate, the sea surface layers of the area under estuarine influence showed a very moderate salinity fall and a nearly total depletion in nitrates, whereas higher levels of these nutrients were found in deeper, more saline, layers. Small-scale PK activity variations in mesozooplankton appear to be closely correlated to nitrate integration values within the water column. The results were analysed in comparison with literature reports. The study produced a coherent overall interpretation, which strongly supports the reliability of this new biochemical tool in detecting assimilation of trace carbohydrates in the diet of mesozooplankton.

Pyruvate kinase (PK) activity measurements are used to assess the role of carbohydrates in global feeding of mesozooplankton communities inhabiting an estuary plume. As a consequence of a remarkably low freshwater discharge rate, the sea surface layers of the area under estuarine influence showed a very moderate salinity fall and a nearly total depletion in nitrates, whereas higher levels of these nutrients were found in deeper, more saline, layers. Small-scale PK activity variations in mesozooplankton appear to be closely correlated to nitrate integration values within the water column. The results were analysed in comparison with literature reports. The study produced a coherent overall interpretation, which strongly supports the reliability of this new biochemical tool in detecting assimilation of trace carbohydrates in the diet of mesozooplankton.

Based on a field study and several mesocosm experiments, I evaluated the use of pigments as chemotaxonomical biomarkers for phytoplankton community composition in the Baltic Sea and I examined effects of inorganic nutrients on the dynamics of carotenoids and thiamine (vitamin B1) at the phytoplankton–copepod level in marine pelagic food webs. My results show that HPLC pigment analysis combined with CHEMTAX data processing was an accurate alternative to microscopic analysis of Baltic Sea phytoplankton. Experimental supply of N, P and Si affected copepod growth and biochemical status via changes in biomass and composition of their phytoplankton diet. Net population growth rates were generally higher when phytoflagellates dominated (low Si:N ratio) and lower when diatoms dominated (high Si:N ratio). Copepod body concentrations of astaxanthin decreased with fertilization. Correlations with reduced under-water irradiance were consistent with the photo-protective function of this antioxidant. Thiamine concentrations in phytoplankton also decreased with fertilization. In copepods, low Si:N ratios resulted in higher thiamine concentrations than high Si:N ratios. Thiamine concentration and degree of phosphorylation were useful as indicators of thiamine shortage both in phytoplankton and copepods. The concentrations of thiamine and astaxanthin in the copepod communities were positively correlated. As copepods constitute a major link between pelagic primary producers and higher trophic levels, fertilization effects may be responsible for astaxanthin and thiamine deficiencies in salmon suffering from the M74 syndrome, which appeared concurrently with large-scale eutrophication in the Baltic Sea. As both thiamine and astaxanthin are deficient in M74-affected salmon, there is a need for physiological and molecular investigations of possible interactions between the two compounds in living cells.

Based on a field study and several mesocosm experiments, I evaluated the use of pigments as chemotaxonomical biomarkers for phytoplankton community composition in the Baltic Sea and I examined effects of inorganic nutrients on the dynamics of carotenoids and thiamine (vitamin B1) at the phytoplankton–copepod level in marine pelagic food webs. My results show that HPLC pigment analysis combined with CHEMTAX data processing was an accurate alternative to microscopic analysis of Baltic Sea phytoplankton. Experimental supply of N, P and Si affected copepod growth and biochemical status via changes in biomass and composition of their phytoplankton diet. Net population growth rates were generally higher when phytoflagellates dominated (low Si:N ratio) and lower when diatoms dominated (high Si:N ratio). Copepod body concentrations of astaxanthin decreased with fertilization. Correlations with reduced under-water irradiance were consistent with the photo-protective function of this antioxidant. Thiamine concentrations in phytoplankton also decreased with fertilization. In copepods, low Si:N ratios resulted in higher thiamine concentrations than high Si:N ratios. Thiamine concentration and degree of phosphorylation were useful as indicators of thiamine shortage both in phytoplankton and copepods. The concentrations of thiamine and astaxanthin in the copepod communities were positively correlated. As copepods constitute a major link between pelagic primary producers and higher trophic levels, fertilization effects may be responsible for astaxanthin and thiamine deficiencies in salmon suffering from the M74 syndrome, which appeared concurrently with large-scale eutrophication in the Baltic Sea. As both thiamine and astaxanthin are deficient in M74-affected salmon, there is a need for physiological and molecular investigations of possible interactions between the two compounds in living cells.

Based on a field study and several mesocosm experiments, I evaluated the use of pigments as chemotaxonomical biomarkers for phytoplankton community composition in the Baltic Sea and I examined effects of inorganic nutrients on the dynamics of carotenoids and thiamine (vitamin B1) at the phytoplankton–copepod level in marine pelagic food webs. My results show that HPLC pigment analysis combined with CHEMTAX data processing was an accurate alternative to microscopic analysis of Baltic Sea phytoplankton. Experimental supply of N, P and Si affected copepod growth and biochemical status via changes in biomass and composition of their phytoplankton diet. Net population growth rates were generally higher when phytoflagellates dominated (low Si:N ratio) and lower when diatoms dominated (high Si:N ratio). Copepod body concentrations of astaxanthin decreased with fertilization. Correlations with reduced under-water irradiance were consistent with the photo-protective function of this antioxidant. Thiamine concentrations in phytoplankton also decreased with fertilization. In copepods, low Si:N ratios resulted in higher thiamine concentrations than high Si:N ratios. Thiamine concentration and degree of phosphorylation were useful as indicators of thiamine shortage both in phytoplankton and copepods. The concentrations of thiamine and astaxanthin in the copepod communities were positively correlated. As copepods constitute a major link between pelagic primary producers and higher trophic levels, fertilization effects may be responsible for astaxanthin and thiamine deficiencies in salmon suffering from the M74 syndrome, which appeared concurrently with large-scale eutrophication in the Baltic Sea. As both thiamine and astaxanthin are deficient in M74-affected salmon, there is a need for physiological and molecular investigations of possible interactions between the two compounds in living cells.

Based on a field study and several mesocosm experiments, I evaluated the use of pigments as chemotaxonomical biomarkers for phytoplankton community composition in the Baltic Sea and I examined effects of inorganic nutrients on the dynamics of carotenoids and thiamine (vitamin B1) at the phytoplankton–copepod level in marine pelagic food webs. My results show that HPLC pigment analysis combined with CHEMTAX data processing was an accurate alternative to microscopic analysis of Baltic Sea phytoplankton. Experimental supply of N, P and Si affected copepod growth and biochemical status via changes in biomass and composition of their phytoplankton diet. Net population growth rates were generally higher when phytoflagellates dominated (low Si:N ratio) and lower when diatoms dominated (high Si:N ratio). Copepod body concentrations of astaxanthin decreased with fertilization. Correlations with reduced under-water irradiance were consistent with the photo-protective function of this antioxidant. Thiamine concentrations in phytoplankton also decreased with fertilization. In copepods, low Si:N ratios resulted in higher thiamine concentrations than high Si:N ratios. Thiamine concentration and degree of phosphorylation were useful as indicators of thiamine shortage both in phytoplankton and copepods. The concentrations of thiamine and astaxanthin in the copepod communities were positively correlated. As copepods constitute a major link between pelagic primary producers and higher trophic levels, fertilization effects may be responsible for astaxanthin and thiamine deficiencies in salmon suffering from the M74 syndrome, which appeared concurrently with large-scale eutrophication in the Baltic Sea. As both thiamine and astaxanthin are deficient in M74-affected salmon, there is a need for physiological and molecular investigations of possible interactions between the two compounds in living cells.

[EN] Information obtained between 1982 and 1986 on the abunclance and distribution of some inorganic nutients (nitrite, nitrate, ammonium, phosphate and silicate) in the bays of Fangar and Alfacs, located to the north and south of the Ebro Delta respectively, is described. [...], [ES] Se presenta información acerca de la abundancia y distribución espacio-temporal de algunos nutrientes inorgánicos (nitrito, nitrato, amonio, fosfato y silicato) en las bahías del FAngar y de els Alfacs, situadas respectivamente al norte y al sur del delta del Ebro que fue obtenida en diversas campañas realizadas entre 1982 y 1986. [...]

Přestože lignit představuje cennou chemickou surovinu, i v současnosti je využíván převážně jako palivo v energetickém průmyslu. Tato aplikace je z ekonomického i ekologického hlediska nevhodná. Předložená bakalářská práce se proto zaměřuje na sorpční schopnosti lignitu se zvláštním důrazem na možnosti jejich využití v jeho alternativních, převážně zemědělských, aplikacích. V experimentální části práce byla podrobně studována sorpce a desorpce modelových anorganických živin (konkrétně dusičnanů a fosforečnanů jako hlavních složek standardních anorganických hnojiv). Výsledky těchto experimentů poskytují bližší představu o možnostech využití lignitu jako nosiče těchto živin nebo jako organického doplňku klasických NPK zemědělských hnojiv., Although lignit represents a valuable chemical substrate, it has been utilized mostly as a fuel in energetic industry. This application is not cost-effective at all and provides a negative ecological impact. Therefore, this bachelor thesis focuses on sorption properties of lignite utilizable in its alternative, mostly agricultural applications. Experimental part of the work deals with sorption and desorption of model inorganic nutrients (nitrates and phosphates as main components of standard inorganic fertilizers). Results of the experiments provides closer view on an application potential of lignite as a carrier of these nutrients or as an organic supplement to traditional NPK agricultural fertilizers.

Přestože lignit představuje cennou chemickou surovinu, i v současnosti je využíván převážně jako palivo v energetickém průmyslu. Tato aplikace je z ekonomického i ekologického hlediska nevhodná. Předložená bakalářská práce se proto zaměřuje na sorpční schopnosti lignitu se zvláštním důrazem na možnosti jejich využití v jeho alternativních, převážně zemědělských, aplikacích. V experimentální části práce byla podrobně studována sorpce a desorpce modelových anorganických živin (konkrétně dusičnanů a fosforečnanů jako hlavních složek standardních anorganických hnojiv). Výsledky těchto experimentů poskytují bližší představu o možnostech využití lignitu jako nosiče těchto živin nebo jako organického doplňku klasických NPK zemědělských hnojiv., Although lignit represents a valuable chemical substrate, it has been utilized mostly as a fuel in energetic industry. This application is not cost-effective at all and provides a negative ecological impact. Therefore, this bachelor thesis focuses on sorption properties of lignite utilizable in its alternative, mostly agricultural applications. Experimental part of the work deals with sorption and desorption of model inorganic nutrients (nitrates and phosphates as main components of standard inorganic fertilizers). Results of the experiments provides closer view on an application potential of lignite as a carrier of these nutrients or as an organic supplement to traditional NPK agricultural fertilizers.

Přestože lignit představuje cennou chemickou surovinu, i v současnosti je využíván převážně jako palivo v energetickém průmyslu. Tato aplikace je z ekonomického i ekologického hlediska nevhodná. Předložená bakalářská práce se proto zaměřuje na sorpční schopnosti lignitu se zvláštním důrazem na možnosti jejich využití v jeho alternativních, převážně zemědělských, aplikacích. V experimentální části práce byla podrobně studována sorpce a desorpce modelových anorganických živin (konkrétně dusičnanů a fosforečnanů jako hlavních složek standardních anorganických hnojiv). Výsledky těchto experimentů poskytují bližší představu o možnostech využití lignitu jako nosiče těchto živin nebo jako organického doplňku klasických NPK zemědělských hnojiv., Although lignit represents a valuable chemical substrate, it has been utilized mostly as a fuel in energetic industry. This application is not cost-effective at all and provides a negative ecological impact. Therefore, this bachelor thesis focuses on sorption properties of lignite utilizable in its alternative, mostly agricultural applications. Experimental part of the work deals with sorption and desorption of model inorganic nutrients (nitrates and phosphates as main components of standard inorganic fertilizers). Results of the experiments provides closer view on an application potential of lignite as a carrier of these nutrients or as an organic supplement to traditional NPK agricultural fertilizers.

Přestože lignit představuje cennou chemickou surovinu, i v současnosti je využíván převážně jako palivo v energetickém průmyslu. Tato aplikace je z ekonomického i ekologického hlediska nevhodná. Předložená bakalářská práce se proto zaměřuje na sorpční schopnosti lignitu se zvláštním důrazem na možnosti jejich využití v jeho alternativních, převážně zemědělských, aplikacích. V experimentální části práce byla podrobně studována sorpce a desorpce modelových anorganických živin (konkrétně dusičnanů a fosforečnanů jako hlavních složek standardních anorganických hnojiv). Výsledky těchto experimentů poskytují bližší představu o možnostech využití lignitu jako nosiče těchto živin nebo jako organického doplňku klasických NPK zemědělských hnojiv., Although lignit represents a valuable chemical substrate, it has been utilized mostly as a fuel in energetic industry. This application is not cost-effective at all and provides a negative ecological impact. Therefore, this bachelor thesis focuses on sorption properties of lignite utilizable in its alternative, mostly agricultural applications. Experimental part of the work deals with sorption and desorption of model inorganic nutrients (nitrates and phosphates as main components of standard inorganic fertilizers). Results of the experiments provides closer view on an application potential of lignite as a carrier of these nutrients or as an organic supplement to traditional NPK agricultural fertilizers.

Přestože lignit představuje cennou chemickou surovinu, i v současnosti je využíván převážně jako palivo v energetickém průmyslu. Tato aplikace je z ekonomického i ekologického hlediska nevhodná. Předložená bakalářská práce se proto zaměřuje na sorpční schopnosti lignitu se zvláštním důrazem na možnosti jejich využití v jeho alternativních, převážně zemědělských, aplikacích. V experimentální části práce byla podrobně studována sorpce a desorpce modelových anorganických živin (konkrétně dusičnanů a fosforečnanů jako hlavních složek standardních anorganických hnojiv). Výsledky těchto experimentů poskytují bližší představu o možnostech využití lignitu jako nosiče těchto živin nebo jako organického doplňku klasických NPK zemědělských hnojiv., Although lignit represents a valuable chemical substrate, it has been utilized mostly as a fuel in energetic industry. This application is not cost-effective at all and provides a negative ecological impact. Therefore, this bachelor thesis focuses on sorption properties of lignite utilizable in its alternative, mostly agricultural applications. Experimental part of the work deals with sorption and desorption of model inorganic nutrients (nitrates and phosphates as main components of standard inorganic fertilizers). Results of the experiments provides closer view on an application potential of lignite as a carrier of these nutrients or as an organic supplement to traditional NPK agricultural fertilizers.

Přestože lignit představuje cennou chemickou surovinu, i v současnosti je využíván převážně jako palivo v energetickém průmyslu. Tato aplikace je z ekonomického i ekologického hlediska nevhodná. Předložená bakalářská práce se proto zaměřuje na sorpční schopnosti lignitu se zvláštním důrazem na možnosti jejich využití v jeho alternativních, převážně zemědělských, aplikacích. V experimentální části práce byla podrobně studována sorpce a desorpce modelových anorganických živin (konkrétně dusičnanů a fosforečnanů jako hlavních složek standardních anorganických hnojiv). Výsledky těchto experimentů poskytují bližší představu o možnostech využití lignitu jako nosiče těchto živin nebo jako organického doplňku klasických NPK zemědělských hnojiv., Although lignit represents a valuable chemical substrate, it has been utilized mostly as a fuel in energetic industry. This application is not cost-effective at all and provides a negative ecological impact. Therefore, this bachelor thesis focuses on sorption properties of lignite utilizable in its alternative, mostly agricultural applications. Experimental part of the work deals with sorption and desorption of model inorganic nutrients (nitrates and phosphates as main components of standard inorganic fertilizers). Results of the experiments provides closer view on an application potential of lignite as a carrier of these nutrients or as an organic supplement to traditional NPK agricultural fertilizers.