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Terrestrial, UAV-borne, and airborne laser scanning point clouds of central European forest plots, Germany, with extracted individual trees and manual forest inventory measurements

Laser scanning point clouds of forest stands were acquired in southwest Germany in 2019 and 2020 from different platforms: an aircraft, an uncrewed aerial vehicle (UAV) and a ground-based tripod. The UAV-borne and airborne laser scanning campaigns cover twelve forest plots of approximately 1 ha. The plots are located in mixed central European forests close to Bretten and Karlsruhe, in the federal state of Baden-Württemberg, Germany. Terrestrial laser scanning was performed in selected locations within the twelve forest plots. Airborne and terrestrial laser scanning point clouds were acquired under leaf-on conditions, UAV-borne laser scans were acquired both under leaf-on and later under leaf-off conditions. In addition to the laser scanning campaigns, forest inventory tree properties (species, height, diameter at breast height, crown base height, crown diameter) were measured in-situ during summer 2019 in six of the twelve 1-ha plots. Single tree point clouds were extracted from the different laser scanning datasets and matched to the field measurements. For each tree entry, point clouds, tree species, position, and field-measured and point cloud-derived tree metrics are provided. For 249 trees, point clouds from all three platforms are available. The tree models form the basis of a single tree database covering a range of species typical for central European forests which is currently being established in the framework of the SYSSIFOSS project.

Sonderforschungsbereich (SFB) 1537: Skalenübergreifende Quantifizierung von Ökosystemprozessen in ihrer räumlich-zeitlichen Dynamik mittels smarter autonomer Sensornetzwerke, Teilprojekt A04: Prozessbasierte Analyse von Ökosystem-Atmosphäre-Austauschs von CO2, H2O und flüchtigen organischen Verbindungen (VOC)

A4.1 Ökosystemreaktionen und Rückkopplungen im Ökosystem-Atmosphäre-Austausch von CO2, H2O und VOCs in einem heterogenen Waldökosystem Um die Lücke zwischen der relativ kleinen Skala eines einzelnen Baumes und einem Waldbestand zu schließen, analysiert A4.1 den Austausch zwischen Ökosystem und Atmosphäre durch Eddy-Kovarianz Messungen von H2O, CO2 und dessen Isoflux (13CO2). Somit lassen sich die Flüsse auf einer integrierten Skala in ihre Komponenten (Ökosystematmung und Bruttoprimärproduktion) auftrennen. Darüber hinaus messen wir die Aufnahme und Freisetzung von VOC durch unsere Wälder und bringen sie mit wichtigen Ökosystemfunktionen in Verbindung, die stark auf Umweltveränderungen reagieren. A4.2 Entwicklung eines auf einem Interbandkaskadenlaser basierenden Messsystems zur Untersuchung des Austauschs zwischen Ökosystem und Atmosphäre von VOCs. Hier entwickeln wir erstmals eine optische spektroskopische Sensortechnologie, um VOCs mit Hilfe der durchstimmbaren Laserabsorptionsspektroskopie (TLAS) zu messen. Dies soll entlang der Konzentrationsgradienten am Messturm und in Verbindung mit Einzelblattküvetten (A3.2) erfolgen.

Geochemical parameters in peat depth profiles from ombrotrophic bogs in North and Central Europe. Fochteloër Veen, the Netherlands

This dataset contains geochemical variables measured in six depth profiles from ombrotrophic peatlands in North and Central Europe. Peat cores were taken during the spring and summer of 2022 from Amtsvenn (AV1), Germany; Drebbersches Moor (DM1), Germany; Fochteloër Veen (FV1), the Netherlands; Bagno Kusowo (KR1), Poland; Pichlmaier Moor (PI1), Austria and Pürgschachen Moor (PM1), Austria. The cores AV1, DM1 and KR1 were taken using a Wardenaar sampler (Royal Eijkelkamp, Giesbeek, the Netherlands) and had diameter of 10 cm. The cores FV1, PM1 and PI1 had an 8 cm diameter and were obtained using an Instorf sampler (Royal Eijkelkamp, Giesbeek, the Netherlands). The cores FV1, DM1 and KR1 were 100 cm, core AV1 was 95 cm, core PI1 was 85 cm and core PM1 was 200 cm. The cores were subsampeled in 1 cm (AV1, DM1, KR1, FV1) and 2 cm (PI1, PM1) sections. The subsamples were milled after freeze drying in a ballmill using tungen carbide accesoires. X-Ray Fluorescence (WD-XRF; ZSX Primus II, Rigaku, Tokyo, Japan) was used to determine Al (μg g-1), As (μg g-1), Ba (μg g-1), Br (μg g-1), Ca (g g-1), Cl (μg g-1), Cr (μg g-1), Cu (μg g-1), Fe (g g-1), K (g g-1), Mg (μg g-1), Mn (μg g-1), Na (μg g-1), P (μg g-1), Pb (μg g-1), Rb (μg g-1), S (μg g-1), Si (μg g-1), Sr (μg g-1), Ti (μg g-1) and Zn (μg g-1). These data were processed and calibrated using the iloekxrf package (Teickner & Knorr, 2024) in R. C, N and their stable isotopes were determined using an elemental analyser linked to an isotope ratio mass spectrometer (EA-3000, Eurovector, Pavia, Italy & Nu Horizon, Nu Instruments, Wrexham, UK). C and N were given in units g g-1 and stable isotopes were given as δ13C and δ15N for stable isotopes of C and N, respectively. Raw data C, N and stable isotope data were calibrated with certified standard and blank effects were corrected with the ilokeirms package (Teickner & Knorr, 2024). Using Fourier Transform Mid-Infrared Spectroscopy (FT-MIR) (Agilent Cary 670 FTIR spectromter, Agilent Technologies, Santa Clara, Ca, USA) humification indices (HI) were determined. Spectra were recorded from 600 cm-1 to 4000 cm-1 with a resolution of 2 cm-1 and baselines corrected with the ir package (Teickner, 2025) to estimate relative peack heights. The HI (no unit) for each sample was calculated by taking the ratio of intensities at 1630 cm-1 to the intensities at 1090 cm-1. Bulk densities (g cm-3) were estimated from FT-MIR data (Teickner et al., in preparation).

Photos of marine litter in the shallow seafloor of the southernmost North and Baltic seas during the Walther Herwig III cruise WH462 in 2022

The dataset is a set of photos of marine litter at the seafloor and corresponding coordinates. The photos were taken in the southernmost North and Baltic seas, between 30.11.2022 and 12.12.2022 during the Walther Herwig III 462 research cruise (Date begin: 29.11.2022 - Date end: 14.12.2022, harbor begin: Bremerhaven - harbor end: Bremerhaven) . The video system used consists of a GoPro HERO 9 black in an aluminium case mounted in the front of the sledge and two lights with a total of 7200 lumen. Three laser pointers mounted in an equilateral triangle (laser center point distance 25.5 cm) provided the size reference for the video observation. The photos were taken as part of a study to visually quantify the amount of marine letter in the seafloor and compare this value with bottom trawl data.

Historical digital terrain model data of the Weser Estuary (HIWEST)

The Weser estuary at the German North Sea coast serves as a fairway to the harbours of Bremerhaven and Bremen. To ensure safe shipping and navigation, the navigation channel depths are nowadays intensively monitored, and have been so in the past. These are valuable data for consulting and research purposes, and enables investigations leading to a better understanding of hydrodynamics, salt intrusion and morphological processes in the estuary, in the present as well as the past. For recent years, thanks to modern monitoring techniques and digitalization, measuring data has been compiled to consistent digital terrain models of high quality and accuracy. For time periods before the 1990ies however, measurements were scarcer and the data are available only in form of printed bathymetrical and nautical charts. The objective of the project “Historical system states of the Weser estuary (HIWEST)” was to: • digitalize depths measurements starting from 1960, • georeference the data points and • process and compile them to digital terrain models that can be used for research and consulting. The project was led and financed by the Federal Waterways Engineering and Research Institute (BAW). It was supported by the Federal Maritime and Hydrographic Agency (BSH) and by the German Water and Shipping Administration (WSV) who provided printed charts and scanned data sets. The smile consulting GmbH was contracted to process the data and compile digital terrain models. One of the main challenges of the project was georeferencing. While georeferencing and projecting in the horizontal domain was comparatively straightforward, the transformation of depths below different chart datums to the Germans mean height reference system represented a challenge. This was accomplished by an algorithm considering spatial polygons provided by BSH and further meta information on the different levelling systems. The accuracy of the data sets differs depending on the quality of the original data. Since the 1990ies, powerful measurement methods such as airborne laser scanning (ALS) and multibeam echo-sounding has led to high resolutions and high data accuracy. In past surveys, the depths were measured in single-beam echo-soundings, often along individual cross sections, and there is no information between these soundings. As a result, the older terrain models are much smoother then the newer ones and contain less detailed information. More technical details can be found in the appendix of the technical report. The following digital terrain models (DTM, in the following the German abbreviation DGM is used) of the Lower and Outer Weser estuary were made available: • DGM 1966, marking the situation before deepening the Outer Weser to SKN-12 m</li> • DGM 1972, marking the situation before deepening the Lower Weser to SKN-9 m</li> • DGM 1981, marking the situation before extensive river works in the Lower Weser</li> • DGM 1996, marking the situation before deepening the Outer Weser to SKN-14 m</li> • DGM 2002, marking the situation after deepening the Outer Weser to SKN-14 m, reference digital terrain model. The years were chosen so they would represent consistent periods not affected by constructive engineering measures such as channel deepenings, and secondly based on optimal data availability. Each data set however consists not only of data from the respective year, but data had to be added from adjacent years. To close gaps, data from recent surveys were used. The data sets span the whole estuary from the North Sea to the tidal weir in the city of Bremen and are available as 1x1 m raster data sets. How to cite the HIWEST data: <strong style="color: red;"> The data set is only to be quoted together with the Technical Report.</strong> Report: Bundesanstalt für Wasserbau (2020): Historical digital terrain models of the Weser Estuary (HIWEST). Technical Report B3955.02.04.70168-6. Bundesanstalt für Wasserbau. https://henry.baw.de/handle/20.500.11970/107521 Data set: Bundesanstalt für Wasserbau (2020): Historical digital terrain model data of the Weser Estuary (HIWEST) [Data set]. Bundesanstalt für Wasserbau. https://doi.org/10.48437/02.2020.K2.5200.0001

Bau und Erprobung eines verkleinerten Prototypen eines laserunterstützten optischen Abwassermengenmessgerätes auf Basis der Ergebnisse des Projektes AZ 05807/01-/03

Zielsetzung und Anlass des Vorhabens: Die Messung von Abwassermengen wird bei steigenden Kosten der Aufbereitung und höheren Anforderungen an Leitungssysteme immer wichtiger. In dem von der DBU geförderten Projekt 05807/01-03 'Entwicklung eines Verfahrens zur Messung der Abwassermenge in teilgefüllten Gerinnen und Freispiegelleitungen' konnten nicht alle Auflagen erfüllt werden. Bedingt durch eine Geschäftsumorientierung nahm die Jüke Systemtechnik GmbH als rechtliche Nachfolgerin der ursprünglichen Antragstellerin Fa. meta GmbH in Altenberge Abstand davon, das Projekt fortzusetzen. Nach Diskussionen mit Fachleuten der Abwassertechnik stellte sich jedoch heraus, dass durchaus ein Interesse besteht, ein Gerät, das nach dem berührungslosen Laser-Korrelationsverfahren arbeitet, zu entwickeln. Zwischenzeitlich durchgeführte Versuche und Überlegungen führten zu einem deutlich verbesserten, leichter anwendbaren Konzept. Fazit: Es konnte gezeigt werden, dass das Korrelationsverfahren zur Messung der Abwassermenge grundsätzlich geeignet ist. Dies gilt sowohl für die Messung im Zulauf als auch im Auslauf. Dabei sind folgende positiven Eigenschaften hervorzuheben: - berührungslose Messung - großer Dynamikbereich - hohe Genauigkeit der Messung der Strömungsgeschwindigkeit und des Durchflusses - variabler Messquerschnitt. Die zu Beginn des Projektes genannte Zielvorstellung ' .. ohne größere bauliche Eingriffe' messen zu können, muss allerdings relativiert werden. Zur Messung ist auch beim Korrelationsverfahren eine halbwegs gleichgerichtete, zur Messanordnung parallele Strömung, frei von großvolumigen Wirbeln, erforderlich. Um dies zu erreichen, sollte das Gerinne über eine Strecke von etwa fünf- bis zehnfacher Gerinnebreite gerade und ohne Querschnittsveränderung ausgeführt sein. In einer für den Dauerbetrieb geeigneten Ausführung sollte anstelle des Schwimmers eine automatische Höhennachführung verwendet werden. Dabei steht dann auch die aktuelle Füllhöhe als Messwert zur Verfügung, so dass auch die jeweils aktuelle Strömungsquerschnittsfläche recht genau bestimmt werden kann. Das tatsächliche Strömungsprofil über den Querschnitt wird mit Hilfe eines Modells, in das die Gerinneabmessungen und die Beschaffenheit der Begrenzungsflächen eingeht, berechnet.

Seabed Images at pilot oyster reefs in the Borkum Reef Ground marine protected area taken in May 2024

Video transects were done using the A.IKANBILISTM hovering autonomous underwater vehicle (HAUV) of the company BeeX (https://beex.sg/a-ikanbilis/), which flew over the reefs along predefined transects at a depth of 0.5m above seabed and at a speed of 1 m s-1. From the dive videos of the HAUV, SBIs were extracted every second. Each SBI features two parallel laser lines 30 cm away from each other. The camera used was a GoPro, the videos and pictures were taken perpendicularly to the seabed. The seabed images provide insights into the general composition of key species, higher systematic groups and ecological guilds. The images contain information on how benthic species are associated to each other. Transect files include individual images, whereas metadata of each image includes diving depth, date/time of transect. Geographical coordinates and time of individual images is unavailable, images have a resolution of 300dpi and a size of 9 to 13 MB.

Seabed Images at pilot oyster reefs in the Borkum Reef Ground marine protected area taken in July 2025

Video transects were done using the A.IKANBILISTM hovering autonomous underwater vehicle (HAUV) of the company BeeX (https://beex.sg/a-ikanbilis/), which flew over the reefs along predefined transects at a depth of 0.5m above seabed and at a speed of 1 m s-1. From the dive videos of the HAUV, SBIs were extracted every 5 seconds. SBIs, each SBI features two parallel laser lines 25 cm away from each other. The camera used was a GoPro, the videos and pictures were taken perpendicularly to the seabed. The seabed images provide insights into the general composition of key species, higher systematic groups and ecological guilds. The images contain information on how benthic species are associated to each other. Transect files include individual images, whereas metadata of each image includes diving depth, date/time of transect. Geographical coordinates of some individual images is unavailable, images have a resolution of 300dpi and a size of 7 to 13 MB.

KI-Ableitung der Straßenbreiten in Freiburg i. Br.

Dieser Datensatz enthält die Straßenbreiten im Freiburger Stadtgebiet, von Bordsteinunterkante zu Bordsteinunterkante, dargestellt als Breitenlinien. Die Straßenbreiten wurden aus den 3D-Punktwolken der Befahrung des Frühjahr 2024 automatisiert abgeleitet, indem die Unterkante der Bordsteine auf beiden Straßenseite identifiziert und lokalisiert wurden. An den Stellen, an denen auf einer oder beiden Seiten der Bordstein nicht identifiziert werden konnte, erfolgte keine Breitebestimmung. Die automatisierte Ableitung wurde nicht manuell nachgearbeitet. Bei groben Verschmutzungen am Fahrbahnrand, Bordsteinabsenkungen, ggf. parkenden Autos und verschiedenem "Straßenmobiliar" (z.B. Poller) kann es daher sein, dass ein "falscher Bordstein" identifiziert wurde und es daher zu einer fehlerhaften Breitebestimmung kam. Wir empfehlen daher die gleichzeitige Einblendung von Luftbildern um eine schnelle Einordnung der Bestimmung vorzunehmen.

Photosynthetic efficiency and symbiont cover of Amphistegina lobifera measured by PAM fluorometry and CLSM during a menthol-DCMU bleaching experiment (Nov–Dec 2022, Bremen, Germany)

This dataset contains experimental data from a one-month aquarium-based bleaching experiment conducted on Large Benthic Foraminifera (Amphistegina lobifera) from 16 November to 16 December 2022 at the Marine Experimental Facility of the Leibniz Centre for Tropical Marine Research (ZMT), Bremen, Germany. The aim of the experiment was to obtain symbiont-free A. lobifera individuals for future re-inoculation studies and symbiont switching experiments. The foraminifera were originally collected in May 2022 at the Interuniversity Institute for Marine Sciences (IUI) in Eilat, Israel (29°30'07.8N, 34°55'04.9E) and maintained in culture in Germany until the start of the experiment. To assess the effectiveness of two chemical agents—menthol and 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU)—in disrupting symbiosis, photosynthetic efficiency (measured as maximum quantum yield, Fv/Fm) was recorded every other day during the first week of the experiment using a Pulse-Amplitude-Modulated (PAM) fluorometer. Fv/Fm measurements were discontinued after the first week due to complete inhibition of photosynthesis. Symbiont coverage (%) was assessed on day one and then weekly until week four using Confocal Laser Scanning Microscopy (CLSM).

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