Abstract
To better understand the outcomes of river restoration, our paper analyzes the variability of the water content in a restored riparian wetland. We focused our demonstration on the case study of the Babina Islet located in the northern Danube Delta. This site was restored in 1994 by opening levees to regain the pristine hydrological regime with both flooding and dry phases depending on the water level of the Danube River. We monitored the wetland by using the Normal Difference Water Index (NDWI) estimated on Landsat scenes for the period 1984–2020. When compared to pre-restoration conditions, we found an increase of the surface-water area. The maximum surface-water area corresponded to the restoration works. Post-implementation of the restoration solution in 1994, the surface-water area is decreasing. The surface-water area pre-restoration is smaller than the surface-water area in present-day conditions, similar to the control site (Small Islet of Brăila), thus confirming the role of hydrology in maintaining the effects of restoration works. Moreover, we detected the increase of drought area since 1984 on both the restored and the control site. This finding appears to be a new challenge for restoring the riparian wetlands of the Lower Danube River. Our paper recommends the use of standardized indicators via satellite remote sensing to understand riparian wetlands functioning at large scale, which could help to design a coherent strategy of river restoration.
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References
Alsdorf DE, Rodríguez E, Lettenmaier DP (2007) Measuring surface water from space. Reviews of Geophysics 45(2):1–24. https://doi.org/10.1029/2006RG000197
Angelopoulos NV, Cowx IG, Buijse AD (2017) Integrated planning framework for successful river restoration projects: Upscaling lessons learnt from European case studies. Environmental Sciences and Policy 76:12–22. https://doi.org/10.1016/j.envsci.2017.06.005
Besacier-Monbertrand AL, Paillex A, Castella E (2014) Short-term impacts of lateral hydrological connectivity restoration on aquatic macroinvertebrates. River Research and Applications 30(5):557–570. https://doi.org/10.1002/rra.2597
Birsan VM, Zaharia L, Chendes V, Branescu E (2014) Seasonal trends in Romanian streamflow. Hydrological Processes 28(15):4496–4505. https://doi.org/10.1002/hyp.9961
Carvalho L, Mackay EB, Cardoso AC et al (2019) Protecting and restoring Europe’s waters: An analysis of the future development needs of the Water Framework Directive. Science of the Total Environment 658:1228–1238. https://doi.org/10.1016/j.scitotenv.2018.12.255
Castillo D, Kaplan D, Mossa J (2016) A synthesis of stream restoration efforts in Florida (USA). River Research and Applications 12https://doi.org/10.1002/rra.3014
Constantinescu S, Achim D, Rus I, Giosan L (2015) Embanking the Lower Danube: from natural to engineered floodplains and back. In Hudson PF, Middelkoop H (eds) Geomorphic approaches to integrate floodplain management of lowland fluvial systems in North America and Europe. Springer, New York 265–288. https://doi.org/10.1007/978-1-4939-2380-9_11
Cordell S, Questad EJ, Asner GP, Kinney KM, Thaxton JM, Uowolo A, Brooks S, Chynoweth MW (2016) Remote sensing for restoration planning: how the big picture can inform stakeholders. Restoration Ecology 25(S2):S147–S154. https://doi.org/10.1111/rec.12448
Dawson SK, Fisher A, Lucas R, Hutchinson DK, Berney P, Keith D, Catford JA, Kingsford RT (2016) Remote Sensing Measures Restoration Successes, but Canopy Heights Lag in Restoring Floodplain Vegetation. Remote Sensing 8(7,542):2–19. https://doi.org/10.3390/rs8070542
Díaz-Delgado R, Aragonés D, Afán I, Bustamante J (2016) Long-Term Monitoring of the Flooding Regime and Hydroperiod of Doñana Marshes with Landsat Time Series (1974–2014). Remote Sensing 8(775):2–19. https://doi.org/10.3390/rs8090775
Dorondel S, Serban S, Tudor M (2021) Ecological Restoration in “Liquid Societies.” Lessons from Eastern Europe Nat Cult 16(2):86–117. https://doi.org/10.3167/nc.2021.160205
Dufour S, Piégay H (2009) From the myth of a lost paradise to targeted river restoration: forget natural references and focus on human benefits. River Research and Applications 25(5):568–581. https://doi.org/10.1002/rra.1239
Eid ANM, Olatubara CO, Ewemoje TA, El-Hennawy MT, Farouk H (2020) Inland Wetland Time-Series Digital Change Detection Based on SAVI and NDWI Indices: Wadi El-Rayan Lakes. Egypt Remote Sensing Applications: Society and Environment 19:100347. https://doi.org/10.1016/j.rsase.2020.100347
Earth Observing System (2020) EOS Land Viewer - satellite observation imagery application. https://eos.com/landviewer/
Finlayson CM, Davis JA, Gell PA, Kingsford RT, Parton KA (2013) The status of wetlands and the predicted effects of global climate change: The situation in Australia. Aquatic Sciences 75(1):73–93. https://doi.org/10.1007/s00027-011-0232-5
Funk A, Martínez-López J, Borgwardt F, Trauner D, Bagstad KJ, Balbi S, Magrach A, Villa F, Hein T (2019) Identification of conservation and restoration priority areas in the Danube River based on the multi-functionality of river-floodplain systems. Science of the Total Environment 654:763–777. https://doi.org/10.1016/j.scitotenv.2018.10.322
Gâștescu P, Știucă R (2008) Delta Dunării. Rezervație a Biosferei. Editura Libris SRL, Bucharest
Gâștescu P, Țuchiu E (2012) The Danube River in the pontic sector – hydrological regime. In: Gâştescu P, William L, Bretcan P (eds), Proceedings of 1st Water and Wetlands Resources Conference. Editura Transversal, Târgoviște 13–26
Gilbert RO (1987) Statistical methods for environmental pollution monitoring. Wiley, New York
González E, Sher AA, Tabacchi E, Masip A, Poulin M (2015) Restoration of riparian vegetation: a global review of implementation and evaluation approaches in the international, peer-reviewed literature. J Environmental Management 158:85–94. https://doi.org/10.1016/j.jenvman.2015.04.033
Global Runoff Database Center (2021) Global Runoff Data Base. https://www.bafg.de/GRDC/EN/Home/homepage_node.html
Grecu F, Zaharia L, Ioana-Toroimac G, Armaș I (2017) Floods and Flash-Floods Related to River Channel Dynamics. In: Radoane M, Vespremeanu-Stroe A (eds) Landform Dynamics and Evolution in Romania. Springer Geography, Springer, Cham 821–844. https://doi.org/10.1007/978-3-319-32589-7_33
Gumiero B, Mant J, Hein T, Elso J, Boz B (2013) Linking the restoration of rivers and riparian zones/wetlands in Europe: Sharing knowledge through case studies. Ecological Engineering 56:36–50. https://doi.org/10.1016/j.ecoleng.2012.12.103
Guo M, Li J, Sheng C, Xu J, Wu L (2017) A Review of Wetland Remote Sensing. Sensors 17(777):2–36. https://doi.org/10.3390/s17040777
Habersack H, Hein T, Stanica A, Liska I, Mair R, Jäger E, Hauer C, Bradley C (2016) Challenges of river basin management: Current status of, and prospects for, the River Danube from a river engineering perspective. Science of the Total Environment 543:828–845. https://doi.org/10.1016/j.scitotenv.2015.10.123
Hachemi K, Grecu F, Ioana-Toroimac G, Constantin DM, Ozer A (2021) The diachronic analysis of island dynamics along the Vedea-Oltenița Danube river sector using SAR imagery. Mediterranean Geoscience Reviews 3:159–173. https://doi.org/10.1007/s42990-020-00042-5
Hamilton SK (2009) Wetlands of Large Rivers: Flood plains. Reference Module in Earth Systems and Environmental Sciences. Encyclopedia of Inland Waters: 607–610. https://doi.org/10.1016/B978-012370626-3.00065-X
Hausner MB, Huntington JL, Nash C et al (2018) Assessing the effectiveness of riparian restoration projects using Landsat and precipitation data from the cloud-computing application ClimateEngine.org. Ecological Engineering 120:432–440. https://doi.org/10.1016/j.ecoleng.2018.06.024
Hein T, Schwarz U, Habersack H, Nichersu I, Preiner S, Willby N, Weigelhofer G (2016) Current status and restoration options for floodplains along the Danube River. Science of the Total Environment 543:778–790. https://doi.org/10.1016/j.scitotenv.2015.09.073
Hopkinson C, Fuoco B, Grant T, Bayley SE, Brisco B, MacDonald R (2020) Wetland hydroperiod Change Along the Upper Columbia River Floodplain, Canada, 1984 to 2019. Remote Sensing 12(408):2–20. https://doi.org/10.3390/rs12244084
Huang C, Chen Y, Wu J (2014) Mapping spatio-temporal flood inundation dynamics at large river basin scale using time-series flow data and MODIS imagery. International Journal of Applied Earth Observation and Geoinformation 26:350–362. https://doi.org/10.1016/j.jag.2013.09.002
Huang C, Chen Y, Zhang S, Wu J (2018) Detecting, Extracting, and Monitoring Surface Water From Space Using Optical Sensors: A Review. Reviews of Geophysics 56:333–360. https://doi.org/10.1029/2018RG000598
Ioana-Toroimac G, Salit F (2016) La restauration hydromorphologique d’un hydrosystème sociale. Etude de cas dans du delta du Danube. Cinq Continents 6(14):219–234
Ioana-Toroimac G, Zaharia L (2016) Hydromorphological priorities of river restoration projects in Romania. In Gâştescu P, Bretcan P (eds.) Proceedings of 3rd Water and Wetlands Resources Conference. Editura Transversal, Târgoviște. 23–30
Ionita M, Badaluta CA, Scholz P, Chelcea S (2018) Vanishing river ice cover in the lower part of the Danube basin – signs of a changing climate. Scientific Reports 8:7948. https://doi.org/10.1038/s41598-018-26357-w
Kendall MG (1975) Rank correlation methods. Charles Griffin, London
Kissel AM, Halabisky M, Scherer RD, Ryan ME, Hansen EC (2020) Expanding wetland hydroperiod data via satellite imagery for ecological applications. Frontiers in Ecology and the Environment 18(8):432–438. https://doi.org/10.1002/fee.2233
Klaus VH, Sintermann J, Kleinebecker T, Hözel N (2011) Sedimentation-induced eutrophication in large river floodplains – an obstacle to restoration? Biological Conservation 144(1):451–458. https://doi.org/10.1016/j.biocon.2010.09.031
Kondolf GM, Boulton AJ, O’Daniel S et al (2006) Process-based ecological river restoration: visualizing three-dimensional connectivity and dynamic vectors to recover lost linkages. Ecological Society 11(2):5
Li L, Vrieling A, Skidmore A, Wang T, Muñoz AR, Turak E (2015) Evaluation of MODIS Spectral Indices for Monitoring Hydrological Dynamics of a Small, Seasonally-Flooded Wetland in Southern Spain. Wetlands 35:851–864. https://doi.org/10.1007/s13157-015-0676-9
Lisenby P, Croke J, Fryirs K (2016) Geomorphic effectiveness: a linear concept in a non-linear world. Earth Surface Processes and Landforms. https://doi.org/10.1002/esp.4096
Maaß AL, Schüttrumpf H (2019) Reactivation of floodplains in river restorations: long-term implications on the mobility of floodplain sediment deposits. Water Resources Research 55:8178–8196. https://doi.org/10.1029/2019WR024983
Mann HB (1945) Non-parametric tests against trend. Econometrica 13:163–171
Mann HB, Whitney DR (1947) On a test whether one of two random variables is stochastically larger than the other. Annals of Mathematical Statistics 18:50–60
Marttunen M, Weber C, Åberg U, Lienert J (2019) Identifying relevant objectives in environmental management decisions: An application to a national monitoring program for river restoration. Ecological Indicators 101:851–866. https://doi.org/10.1016/j.ecolind.2018.11.042
McFeeters SK (1996) The use of the Normalized Difference Water Index (NDWI) in the delineation of open water features. International Journal of Remote Sensing 171:1425–1432
McFeeters SK (2013) Using the Normalized Difference Water Index (NDWI) within a Geographic Information System to detect swimming pools for mosquito abatement: a practical approach. Remote Sensing 5:3544–3561. https://doi.org/10.3390/rs5073544
Meng B, Liu J, Bao K, Sun B (2020) Methodologies and Management Framework for Restoration of Wetland Hydrologic Connectivity: A Synthesis. Integrated Environmental Assessment and Management 16(4):438–451. https://doi.org/10.1002/ieam.4256
Mikhailova MV, Isupova MV, Morozov VN (2020) Hydrological-Morphometric Characteristics of Danube Delta Branches in the Backwater Zone. Water Resources 47(3):366–373. https://doi.org/10.1134/S0097807820030112
Morandi B, Piégay H, Lamouroux N, Vaudor L (2014) How is success or failure in river restoration projects evaluated? Feedback from French restoration projects. Journal of Environmental Management 137:178–188. https://doi.org/10.1016/j.jenvman.2014.02.010
Morandi B, Kail J, Toedter A, Wolter C, Piégay H (2017) Diverse approaches to implement and monitor river restoration: a comparative perspective in France and Germany diverse approaches to implement and monitor river restoration. Environmental Management 60:931–946. https://doi.org/10.1007/s00267-017-0923-3
Natural Water Retention Measures (2015) European NWRM Platform. Catalogue of measures. Babina Restoration Project, Romania. http://nwrm.eu/case-study/babina-restoration-project-romania
Otte ML, Fang WT, Jiang M (2021) A Framework for Identifying Reference Wetland Conditions in Highly Altered Landscapes. Wetlands 41:40. https://doi.org/10.1007/s13157-021-01439-0
Pasternack GB (2020) River Restoration: Disappointing, Nascent, Yet Desperately Needed. Reference Module in Earth Systems and Environmental Sciences. https://doi.org/10.1016/B978-0-12-409548-9.12449-2
Pekárová P, Pramuk B, Halmová D, Miklánek P, Prohaska S, PekárJ, (2016) Identification of long-term high-flow regime changes in selected stations along the Danube River. Journal of Hydrology and Hydromechanics 64(4):393–403. https://doi.org/10.1515/johh-2016-0045
Pekárová P, Gorbachova L, Mitkova VB, Pekár J, Miklanek P (2019) Statistical Analysis of Hydrological Regime of the Danube River at Ceatal Izmail Station. IOP Conference Series: Earth and Environmental Science 22:012035. https://doi.org/10.1088/1755-1315/221/1/012035
Perennou C, Guelmami A, Paganini M, Philipson P, Poulin B, Strauch A, Tottrup C, Truckenbrodt J, Geijzendorffer IR (2018) Chapter six - Mapping Mediterranean wetlands with remote sensing: a good-looking, map is not always a good map. Advances in Ecological Research 58:24377. https://doi.org/10.1016/bs.aecr.2017.12.002
Pettitt AN (1979) A Non-Parametric Approach to the Change-Point Problem. Journal of the Royal Statistical Society. Series C (Applied Statistics) 28(2):26–135. https://doi.org/10.2307/2346729
Petts GE, Gurnell AM (2005) Dams and geomorphology: Research progress and future directions. Geomorphology 71:27–47. https://doi.org/10.1016/j.geomorph.2004.02.015
Polvi LE, Lind L, Persson H, Mirana-Melo A, Pilotto F, Su X, Nilsson C (2020) Facets and scales in river restoration: Nestedness and interdependence of hydrological, geomorphic, ecological, and biogeochemical processes. Journal of Environmental Management 265:110288. https://doi.org/10.1016/j.jenvman.2020.110288
Reid MA, Reid MC, Thoms MC (2016) Ecological significance of hydrological connectivity for wetland plant communities on a dryland floodplain river, Macintyre River. Australia Aquatic Sciences 78(1):139–158. https://doi.org/10.1007/s00027-015-0414-7
Schneider E, Cernişencu I, Cioacă E et al (2008) Evolution of Babina polder after restoration works, Kraft-Druck, Ettlingen
Smith LC (1997) Satellite remote sensing of river inundation area, stage, and discharge: a review. Hydrological Processes 11(10):1427–1439. https://doi.org/10.1002/(SICI)1099-1085(199708)11:10%3c1427::AID-HYP473%3e3.0.CO;2-S
Stagl JC, Hattermann FF (2015) Impacts of Climate Change on the Hydrological Regime of the Danube River and Its Tributaries Using an Ensemble of Climate Scenarios. Water 7(11):6139–6172. https://doi.org/10.3390/w7116139
Staras M (2001) Restoration programme in the Danube Delta: Achievements, benefits and constraints. In: Nijland HJ, Cals MJR (eds) River Restoration in Europe. RIZA Report 2001.023, Lelystad, p 95–102
Știucă R, Nichersu I, Tudor M (2007) The Danube Delta and Wetlands projects in Romania. In Final Wetlands Workshop of the UNDP/GEF Danube Regional Project 18-20 April 2007, Tulcea, Romania. http://www.undp-drp.org/pdf/Workshops_and_Meetings%20-%20Phase%20II/2007-04-18_Wetlands_Wshp/22%20M%20Tudor.pdf
Theia-land (2021) Hydroweb application - time series of water levels in the rivers and lakes around the world. http://hydroweb.theia-land.fr/?lang=en&basin=Danube
Tockner K, Uehlinger U, Robinson CT (2008) Rivers of Europe. Academic Press, Amsterdam
Watts RJ, Richter BD, Opperman JJ, Bowmer KHH (2011) Dam reoperation in an era of climate change. Marine and Freshwater Research 62:321–327. https://doi.org/10.1016/10.1071/MF10047
Wohl E, Lane SN, Wilcox AC (2015) The science and practice of river restoration. Water Resources Research 51:5974–5997. https://doi.org/10.1002/2014WR016874
Wyżga B, Amirowicz A, Bednarska A, Bylak A, Hajdukiewicz H, Kędzior R, Kukuła K, Liro M, Mikuś P, Oglęcki P, Radecki-Pawlik A, Zawiejska J (2020) Scientific monitoring of immediate and long-term effects of river restoration projects in the Polish Carpathians. Ecohydrology & Hydrobiology in Press. https://doi.org/10.1016/j.ecohyd.2020.11.005
WWF (2016) Lower Danube green corridor: floodplain restoration for flood protection. Case study description within European Climate Adaptation Platform Climate-ADAPT. https://climate-adapt.eea.europa.eu/metadata/case-studies/lower-danube-green-corridor-floodplain-restoration-for-flood-protection
Zaharia L (2010) The Iron Gates Reservoir – Aspects concerning hydrological characteristics and water quality. Lakes Reservoirs and Ponds 4:52–69
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Ioana-Toroimac, G., Zaharia, L., Moroșanu, GA. et al. Assessment of Restoration Effects in Riparian Wetlands using Satellite Imagery. Case Study on the Lower Danube River. Wetlands 42, 30 (2022). https://doi.org/10.1007/s13157-022-01543-9
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DOI: https://doi.org/10.1007/s13157-022-01543-9