Analysis of natural background and dredging-induced changes in TSM concentration from MERIS images near commercial harbours in the Estonian coastal sea

Medium Resolution Imaging Spectrometer (MERIS) products with 300 m resolution from 2006 to 2011 were used to evaluate the local background of total suspended matter (TSM) in the vicinity of commercial harbours located along the Estonian coastline in the Baltic Sea. The difference between background TSM maps (mainly influenced by spring bloom, cyanobacterial bloom, resuspension, and river inflow) and dredging period mean maps was used for the estimation of dredging-induced turbidity at the time of dredging operations. Validation of Case II Regional (C2 R) and Free University of Berlin (FUB) MERIS processors with point measurements showed that both processors represent the changes in TSM concentration adequately. C2 R processors showed better statistics (R2 = 0.61, root mean square error = 0.82 mg l–1, SD = 0.77 mg l–1, mean bias = –0.28 mg l–1) compared to the FUB processor. Analysis of monthly mean TSM maps revealed that the variability of TSM concentration, showing the resilience level of the local ecosystem, is very different along the Estonian coastline – varying between 0.75 and 2.60 mg l–1 near the Port of Tallinn, located in the Gulf of Finland, and between 10.04 and 24.23 mg l–1 near the Port of Pärnu, located in the Gulf of Riga. The viability of the method for dredging impact detection was tested by evaluating the dredging-induced turbidity on monthly mean TSM maps for the dredging period in autumn 2008 in Pakri Bay, which is an environmentally sensitive area. A threshold TSM concentration value of >2.26 mg l–1 difference from background TSM was defined as a criterion for dredging impact detection for Pakri Bay. The area of dredging-induced turbidity was between 0.56 and 1.25 km2 and did not reach the environmentally sensitive NATURA 2000 region adjoining Paldiski South Harbour.

[1]  S. Peters,et al.  Comparison of remote sensing data, model results and in situ data for total suspended matter (TSM) in the southern Frisian lakes. , 2001, The Science of the total environment.

[2]  Sindy Sterckx,et al.  Retrieval of Suspended Sediment from Advanced Hyperspectral Sensor Data in the Scheldt Estuary at Different Stages in the Tidal Cycle , 2007 .

[3]  Per Stålnacke,et al.  Riverine input of nutrients to the Gulf of Riga - temporal and spatial variation , 1999 .

[4]  M. Laamanen,et al.  Long-term changes in summer phytoplankton communities of the open northern Baltic Sea , 2007 .

[5]  Roland Doerffer,et al.  Atmospheric correction algorithm for MERIS above case‐2 waters , 2007 .

[6]  Flow, waves and water exchange in the Suur Strait, Gulf of Riga, in 2008 , 2011 .

[7]  L. Sipelgas,et al.  Monitoring the effect of upwelling on the chlorophyll a distribution in the Gulf of Finland (Baltic Sea) using remote sensing and in situ data , 2012 .

[8]  Liis Sipelgas,et al.  Analysis of historical MERIS and MODIS data to evaluate the impact of dredging to monthly mean surface TSM concentration , 2013, Remote Sensing.

[9]  David Doxaran,et al.  Dynamics of the turbidity maximum zone in a macrotidal estuary (the Gironde, France): Observations from field and MODIS satellite data , 2009 .

[10]  Seppo Kaitala,et al.  Identification and quantification of plankton bloom events in the Baltic Sea by continuous pCO2 and chlorophyll a measurements on a cargo ship , 2006 .

[11]  L. Rahm,et al.  Resuspension patterns in the Baltic proper , 2007 .

[12]  Helgi Arst,et al.  Optical investigations of CDOM-rich coastal waters in Pärnu Bay , 2011 .

[13]  T. Kutser,et al.  Operative Monitoring of the Extent of Dredging Plumes in Coastal Ecosystems Using MODIS Satellite Imagery , 2024, Journal of Coastal Research.

[14]  A. Lindfors,et al.  MERIS Case II water processor comparison on coastal sites of the northern Baltic Sea , 2013 .

[15]  Jukka Seppälä,et al.  Ship-of-opportunity based phycocyanin fluorescence monitoring of the filamentous cyanobacteria bloom dynamics in the Baltic Sea , 2007 .

[16]  Carsten Brockmann,et al.  Using MERIS full resolution data to monitor coastal waters : A case study from Himmerfjärden, a fjord-like bay in the northwestern Baltic Sea , 2008 .

[17]  Liis Sipelgas,et al.  Environmental monitoring of water quality in coastal sea area using remote sensing and modeling , 2006, 2006 IEEE US/EU Baltic International Symposium.

[18]  Martti Hallikainen,et al.  A case study of airborne and satellite remote sensing of a spring bloom event in the Gulf of Finland , 2007 .

[19]  L. Sipelgas.  Monitoring the concentration, distribution, origin and size of suspended particles in the water column during harbour dredging in Pakri Bay, the Gulf of Finland , 2011 .

[20]  Guofeng Wu,et al.  Concurrent monitoring of vessels and water turbidity enhances the strength of evidence in remotely sensed dredging impact assessment. , 2007, Water research.

[21]  T. Schroeder,et al.  Retrieval of atmospheric and oceanic properties from MERIS measurements: A new Case‐2 water processor for BEAM , 2007 .

[22]  T. Soomere,et al.  Towards quantifying variations in wind parameters across the Gulf of Finland , 2010 .

[23]  R. Doerffer,et al.  The MERIS Case 2 water algorithm , 2007 .

[24]  K. Kononen,et al.  Effect of upwelling on the pelagic environment and bloom-forming cyanobacteria in the western Gulf of Finland, Baltic Sea , 2005 .

[25]  Mariano Bresciani,et al.  Validation of MERIS bio-optical products with in situ data in the turbid Lithuanian Baltic Sea coastal waters , 2012 .

[26]  A. Lehmann,et al.  Detailed assessment of climate variability of the Baltic Sea area for the period 1958-2009 (solicited) , 2011 .

[27]  Guofeng Wu,et al.  Using remotely sensed suspended sediment concentration variation to improve management of Poyang Lake, China , 2013 .

[28]  Richard L. Miller,et al.  Using MODIS Terra 250 m imagery to map concentrations of total suspended matter in coastal waters , 2004 .

[29]  R. Colwell.  Remote sensing of the environment , 1980, Nature.

[30]  K. Edelvang,et al.  CASI data utilized for mapping suspended matter concentrations in sediment plumes and verification of 2-D hydrodynamic modelling , 2000 .

[31]  P. Fearns,et al.  Digitise This! A Quick and Easy Remote Sensing Method to Monitor the Daily Extent of Dredge Plumes , 2012, PloS one.

[32]  R. Doerffer,et al.  MERIS potential for coastal zone applications , 1999 .

[33]  U. Raudsepp,et al.  A Fuzzy Logic Model to Describe the Cyanobacteria Nodularia spumigena Blooms in the Gulf of Finland, Baltic Sea , 2005, Hydrobiologia.

[34]  T. M. Lillesand,et al.  Testing the utility of simple multi-date Thematic Mapper calibration algorithms for monitoring turbid inland waters , 1991 .

[35]  Shanti Reddy,et al.  Evaluation of satellite remote sensing for operational monitoring of sediment plumes produced by dredging at Hay Point, Queensland, Australia , 2007 .