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Project manager Jesper H. Andersen This report contains, as said in the title, the supplementary material to the synthesis report from the ECOMAR project (2018- 2020). The supplementary material consists of three parts: 1) Annex A, being the data sets and layers dealing with human pressures and activities, 2) Annex B, being the data set related to ecosystem components and analogue data sets, and 3) Annex C, being additional data used for the mapping of potentially cumulative effects in Danish marine waters as well as maps of results mentioned, but not show in the synthesis report. For each data set, a specific reference to the data authoring organization as well as contact information for the Data Author. THE VELUX FOUNDATIONS

Kystdirektoratet, Institut for Geovidenskab og Naturforvaltning ved Københavns Universitet, GEUS og NIRAS har siden 2013 samarbejdet omkring anvendelse og udvikling af metoder til opmåling og monitering med flybåren grøn laser, der, i modsætning til traditionel laseropmåling, også tillader måling af havbunden på vanddækkede arealer. Vi præsenterer resultater af opmålinger med flybåren grøn laser langs Nordsjællands kyst samt i Vadehavet (figur) og perspektiverer disse i forhold til fremtidig anvendelsesområder for kystnære opmålinger af dybdeforhold og i miljømonitering. Grøn laser kan anvendes til mange formål og gerne i kombination med andre data som luftfotos, in situ målinger af sedimenttransport, on-site validering af bundforhold, satellitdata mv. Detaljeret kortlægning af kystzonen er vigtig i forhold til morfologi, sedimenter og geologi, især i forhold til den fremtidige kystudvikling set i lyset af klimaændringer og et potentielt ændret stormklima. Et godt kendskab til de faktiske dybde- og bundforhold vil give bedre mulighed for fremskrivning af erosion/kystlinjeændringer, for modellering af oversvømmelsesfaren langs kysterne og optimering af nuværende og fremtidige kystbeskyttelsestiltag langs kysterne. Endvidere vil teknologien styrke forvaltning og monitering i relation til eksempelvis sandfodring/-bypass og habitatkortlægning. Anvendelse af grøn laser giver mulighed for ”sømløs” kortlægning af hele kystzonen, inklusiv overgangszonen land-hav; en forbedret og mere effektiv søopmåling; at favne små- og storskala morfologi i hidtil uset detaljeringsgrad og nøjagtighed, og mulighed for at efterleve EU-målsætninger om integreret, økosystembaseret kystzoneforvaltning. Et fortsat og udvidet samarbejde omkring anvendelse af grøn laser vil bidrage til en effektiv og bæredygtig udnyttelse og beskyttelse af landets naturressourcer især indenfor kystzonen, hvor informationsniveauet indtil videre er utilstrækkeligt. Fremadrettet ses desuden store perspektiver i anvendelse af civile droner (UAV’s) til grøn laseropmåling. Dette kræver dog endnu udvikling bl.a. i at mindske vægten af måleudstyr.

Shallow water environments in the land-sea transition zone are challenging to map in high spatial resolution at large spatial scales. Historically this has led to gaps (white ribbons) between terrestrial and marine surveys. Topobathymetric LiDAR (Light Detection And Ranging), also referred to as green LiDAR which is able to penetrate through water, holds the potential to close this gap. However, water column turbidity poses limitations to the penetration of the green laser beam, and water column refraction of the laser beam poses limitations to the scale of features which can be resolved at the seabed. The aim of this study is to investigate the performance of topobathymetric LiDAR in shallow water environments in relation to resolving small-scale morphological features at landscape scale. More specifically, the objectives are: 1) to determine the spatial resolution as well as the horizontal and vertical precision of green LiDAR based on object detection; and 2) to assess the potential of topobathymetric LiDAR as a tool to combine and integrate terrestrial and marine mapping and related investigations in the land-sea transition zone. Topobathymetric LiDAR surveys were carried out in spring 2014 on an app. 7 km reach of the Ribe Vesterå river and in a 5 km x 10 km section of the Knudedyb tidal inlet in the Danish Wadden Sea using the airborne hydrographic laser scanner RIEGL® VQR-820-G. Prior to the surveys three geometrically defined objects (steel frames with dimensions of 0.8 m x 0.8 m x 0.25 m) were placed within the survey area in the river section, and in a back-barrier tidal channel and on a back-barrier salt marsh in the tidal inlet system, respectively. The exact locations of the three objects were determined by a Trimble® R8 GNSS Receiver. The preliminary results show that the topobathymetric LiDAR system can detect the three objects. However, the sharp corners and edges of the objects are not perfectly resolved due to a combination of point density, which primarily is a function of effective measurement rate and flight height and speed, and seabed footprint size, which primarily is a function of water depth and water column refraction. The horizontal and vertical precision of the LiDAR system is at sub-decimetre scale at a 95% confidence level. This suggests that topobathymetric LiDAR is capable of resolving relatively small-scale morphological features in challenging shallow water environments in the land-sea transition zone at landscape scale, as large spatial areas can be covered within short time, thereby enabling a closing of the historical gap between terrestrial and marine surveys.