Monitoring of Marine Systems (Fach) / Part B (Lektion)

Alexandra Cravo

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• Why monitor coastal systems Highly productive due to upwelling - high PP highly populate = high anthropogenic pressures interrface system of river/ocean = high fluvial influx knowledge gaps economical importance (aquaculture, fisheries)
• POGO general and their 3 point mission Partnership of global ocean observation =forum of directors of marine institutions to promote oceanography focusing on implementation of international and integrated ocean observation systems  Mission:  1. lead innovation and development of ocean observation systems 2. development of key skills, capabilities, capacities 3. work with government, industry, foundations Blue Planet: brings together all existing observation programs
• Ocean Sites long term fixed observation points 
• GOOS Global Ocean Observing system Program of intergovernmental commission (IOC) of UNESCO measure: physics, biogeochemistry,  and biology of an ecosystem  (eurogoos) 
• IbiRoos and their goals development and implementation of observation system of IBI roos area (france, portugal, spain, ireland, UK Goals implement online operational marine data generate reliable descriptors for actual marine conditions of ibi roos area provide analysis, forecast and models establish marine data base work together mit multinational agencies
• ESMO European multidisciplinary seafloor and water coloumn observatory  =explore the ocean and gain better understanding of phenomena  have regional facilities to measure conditions water coloumn and seafloor (biogeochemical & biological)                                                                                                                      automated laboratories hosting multiple sensors (either autonomous or connected via cable)
• Copernicus Marine service uses satelilite information and in situ measurements to provide state of the art analysis and daily forecasts Ocean Monitor Indicator (OMI) tracks changes in system related to climate change (eg chlorophyll trend 1997-2017) Ocean State Report: yearly report on global ocean condition based on expert analysis - used by scientists and decision makers!
• Global Observing System names POGO Ocean Sites GOOS IbiROOS Euroocean ESMO Copernicu Marine Service
• Radar Systems a) large scale b) high requency a) large scale radar system: used for maritime traffic control, hazardous area monitoing, patrol for unidentified vessels, port monitoring b) high frequency radar systems: used for measuring spead and direction of ocean surface currents in real time 
• image page 12 labeling equipment glierds,,,
• Saturn Observation Systm understand behavor of rio colombia, estuary and adjacent pacific ocean coastal area Use LOBO (Land/Ocean Biogeochemical ROV) use ESP (Environmental Sample Processor): mbari on site in situ collection and analysis
• MBARI Monterey Bay Aquarium research institute =Plan, Design, build, test and deploy  high tech equipment and instruments to answer key questions about the ocean
• Problems in Equipment ain issue is biofouling/biological films: adsorbed material interferes with electrochemical sensor Signal and influences results strongly! Requires frequent cleaning or eg copper case for antifouling! Biggest problem with fixed sensors, protable not so much as cleaned anyway
• Traditional Sampling Methods Sensors and their types Sensors for Salinity, temperature, partial carbon (pCO2), Oxygen, Macro Nutrients, Metals, Chlorophyll, other gases Types: chemical, electrochemical, optical (fluoresence)
• chemical sensors, functioning,advantages, limitations, examples chemical sensors convert a chemical signal into an analytic one functioning: Diffusion of analyte on active surface - requires reversible chemistry                                         physical properties must be detectable  or reaction rate measurements Advantages: very simple and no moving parts with low energy consumption. Can be used for remote sensing when connected to fiber optics Limitations: Requires development of new reversal chemistries and kinetic methods                                     difficult to maintain calibration                                                                                                trade of between response rate and sensitivity Examples: pH Electrode, Oxygen Electrode
• partial Carbon Measurements General and instruments measured by spectrophotometry, in liquid phase by colourmetry based on reagent - using 3 wavelengths (810, 596,434nm) SAMI-CO2 = Submersible autonomous moored pCO2  instruments (coupling with more sensors) SOLO Robotic Carbon Observer- measures inorganic and organic particulate Carbon, equipped with GPS and faster data aquisition than Argo network. Plus can depict anthropogenic influence by giving information about atmospheric carbon emission CARIOCA - Carbon Interface Ocean Atmosphere - autonomous drifting buoy for pCO2 to quantify ocean/atmospheric changes, sending data via Argo satellite network giving hourly measurements over one year period of time high plankton activity results in low pCO2 as it is consumed by plankton
• Types of Dissolved Oxygen Sensors Optical Sensors: Measure the luminescnece which is influenced by presence of oxygen. 2 types of sensors a) lifetime based optical sensor b)intensity based optical sensor Clark Electrochemical Sensor 2 types: a) polarographic sensor (rapid pules, steady state) and b) Galvanic Sensor >mostly used bc cheap but high deviation due to biofilming (~15%)  >>better is gas tension device (~1%) but takes long time due to thick membrane
• Oxygen Electrochemical Sensor General and differences b/w polarographic and galvanic 1.Oxygen permeable membrane confines anode and cathode in electrolyte solution (KCI) 2.Oxygen molecules diffuse through membrane proportional to pressure difference            3.O2 is reduced at the cathode, electrical signal travels to anode and then to the instrument    4.magnitude of the volts of direct current (VDC) correlates with the O2 concentration Polarographic: Anode (silver), Cathode (gold) need extra voltage impulse for reaction and during oxidation silver chloride attaches to anode - clear electrolyte Galvanic: Anode (Zinc) and Cathode (silver) - no need of extra voltage to give impulse and during oxidation zinc hydroxide detaches from anode - electrolyte appearance of white solids
• Oxygen Optical Sensor functioning and example of one existing sensor Chemical film is excited with blue LED, when oxygen is present the fluorescence (emission of light after excitement) is lowered - the emitted light is red and dependant on oxygen level the intensity and lifetime is lowered (inversely proportional) Reading is stabilized faster when water is stirred Usually add a red light to the film for reference (comparisson of lifetimes ) Example is the AAnderaa Optode
• 3 methods to measure Chlorophyll 1. Spectrophotometry 2. High performance liquid chromatography (HPLC) 3. Fluoremetry
• Fluorescence sensor chlorophyll measures cholorphyll-a on relation to phaeopigments light sources with blue LED for excitement - lense system 1 conveys light to sample - lense system 2 collects emitted fluorescence - optical filter seperates excitation and emission wavelength - photodetector for detection >>rhodamin or fluoresceine as fluorescence dyes (detectable at low conc. ) >>chlorophyll when excited emits red light of higher wavelength (650-700) and lower energy Problem: when weak fluorescence, excitement signal might interferwe with measurements new fluorescence sensors for other photopigments, cologanic matter, hdrocarbons and turbidity
• ISUS In Situ ultraviolet Spectrophotometer (light beam trough sample and its intensity of resulting light is compared to sample solution and wiedergegeben in wavelength) = sensitive to biofouling measures dissolved chemicals such as nutrients (nitrate, nitrite) oxygen etc. Each chemical has unique absorption spectrum and can be identified by this
• Fluorometry selection of specific wavelength for excitement and then wavelength of fluorescence is measured (either one wavelength or multiple (emission spectra) Limitations: very time consuming, requires expertise, no continous monitoring (need to manual sample water) New: distinguish taxa via various excitation wavelengths
• Nutrient Sensors General and examples Nutrient conc. very important to understand primary productoin & carbon content a) chemical sensors: for autonomous and lagrangian platforms b)optical sensors (Opto electrodes) like O2: UV Spectrophotometer directly in sea water using UV absorption spectrum Examples ISUS V3: real time, chemical, free sensor - no more reagent based analysis SUNA V2: use in turbid waters (eg estuaries) as it has a lense wiper SUV6: UV Spectrophotometer same as above. university of southhampton developed -
• Chemical Analyzer functioning and Advantages and limitations submersible: chemical analyses in the water (not in the lab) - -Mechanical system collects water sample - pump for transport - reagents for chemical analysis (expensive) >>>consider the matrix change from surface to under water (pressure....) Reading every 5-15mins for 3montsh then change of reagents measures - colormetric,  spectrophotometric, and photometric Advantages: many excisting chemicals with long track record, easy in situ calibration, resistant to biofouling, more complex chemical manipulation possible Limitationaa: mechanically complex, expensive, high power consumption, larg, depth up to 200m after pressure to high
• 3 Types of chemical analyzers 1. OSMO Analyzer: no pump required thus no energy as transport regularted over salinity gradient (not deeper than 10m) - creation of osmotic pressure through semipermeable rigid membran b/w two solutions with different salinity 2. NAS 2E: measures europhication in rivers, estuaries, ocean for up to 12 months and filters water before analysis when turbid water is present 3. DigiScan: smaller, more commercial analyzer for 2 months deployment for NO3 and PO4 also for turbid water (better than ISUS)
• issues Sensors vs issues Analyzers Sensor: biofouling, calibration, few chemicals Analyzer: complex, high costs, expertize, size , power
• Biosensors Nitrate/Nitrite sensors using genetically modiefied bacteria

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