This data was collected and analysed for the project "Dissolved inorganic nitrogen uptake by seaweeds: a global analysis" published in Botanica Marina. Data was compiled between May 2025 and July 2025 from published studies on the uptake kinetics of nitrate (NO₃⁻) and ammonium (NH₄⁺) by marine macroalgae i.e. the rate of Dissolved Inorganic Nitrogen (DIN) uptake rate at a range of DIN concentrations. Each study contained values for the Michaelis-Menten kinetic constants maximum uptake rate (Vmax) and the half saturation constant (Ks), linear uptake gradients, or described biphasic uptake patterns. A total of 84 published studies presenting this data were discovered, with 556 distinct data entries. The project examined DIN uptake rates in marine macroalgae by Phylum, order, experimental irradiance and temperature, geographic location and functional group. Articles were identified through searches on Google Scholar and Web of Science, with all studies reporting Michaelis-Menten kinetic constants or linear uptake slopes included. For each study, we recorded taxonomic information, functional group, the experimental subject (species and algal tissue used), habitat of origin (subtidal, intertidal, or cultured), and season of collection. We also documented experimental conditions, including temperature, irradiance, DIN source (nitrate or ammonium), presence and concentration of other macronutrients (e.g., phosphate or non-target DIN), and the phosphate:DIN ratio of the culture medium. Where available, we extracted kinetic parameters (Vmax, Ks/Km), linear uptake slopes, uptake pattern (saturating, linear, or biphasic), maximum DIN concentration tested, the range of concentrations used in multi-flask experiments, and the time interval over which uptake was measured (for time-course experiments). Geographic coordinates of the study location were also recorded. Each study entry in this dataset includes the full study reference (author and year) and a functional DOI where available (as of November 2025).

Seagrass beds are a dominant marine ecosystem of Tayaritja (the Furneaux Group of Islands) in the north-eastern waters off Tasmania. Historical coarse mapping has indicated extensive beds of Posidonia, Amphibolis, Heterozostera, and Zostera species, potentially comprising some of the largest and deepest seagrass extents found in temperate Australian waters. However, limited data on the distribution and ecological value of these seagrass habitats represents a significant knowledge gap in understanding Australia's wetland natural assets. This project mapped the extent, ecological composition, population structure, and blue carbon value of seagrass beds around Tayaritja, in partnership with the Tasmanian Aboriginal Centre. The study area focused on the coastal waters surrounding Flinders Island in the western Furneaux Group, with mapping extending from the high tide line to the depth limit of reliable optical detection (approximately 30 m), based on analysis of field data and satellite imagery capabilities in the region. This record specifically describes the benthic mapping component of the study. See https://doi.org/10.25959/WRXK-KV06 for imagery annotation data from the field validation campaigns. A combination of close-range remote sensing methods was used to map the extent and ecological values of seagrass beds. The approach developed through this study contributed to the creation of the NESP Standard Operating Procedure (SOP) for Seagrass Mapping using Optical Remote Sensing (https://sustainabledevelopmentreform.github.io/nesp-sop-seagrass-mapping).. High-resolution satellite imagery from Sentinel-2 (10 m) sensors, combined with bathymetric LiDAR data and oceanographic variables, was used to map baseline seagrass extent and composition. A field campaign deployed a Benthic Observation Survey System (BOSS) and unBaited Remote Underwater stereo-Video system (stereo-uBRUV) at approximately 400 locations to validate remote sensing outputs. From these data, maps were produced showing the extent and coverage of seagrass, sand, and macroalgae, and where possible, seagrass species composition, subject to water depth and clarity constraints. See the "Lineage" section of this record for full methodology. Three key types of mapping products were developed: ---Occurrence probability maps--- Continuous probability surfaces (0-100%), modelled from presence/absence data, indicating the likelihood of habitat presence at each pixel for: • Seagrass (all morphologies; > 5% cover observed in underwater field imagery) • Macroalgae species/assemblages • Sand ---Habitat percentage cover maps--- Quantitative estimates of percent cover for each habitat category: • Seagrass (all morphologies) • Macroalgae species/assemblages • Sand ---Derived products--- • Baseline binary presence/extent maps derived from optimised probability thresholds:     ○ Seagrass:     sgprob > 0.5 & sgprob > macroprob & sandcover < 0.9     ○ Macroalgae: macroprob > 0.5 & macroprob > sgprob & sandcover < 0.9     ○ Sand:           sandprob > 0.5 & sandcover < 0.2 • Predicted seagrass species composition of binary extent map. • Fractional cover visualisation: combining cover percentages of multiple habitats into a single composite product • Composite habitat maps: combining binary habitat extents and delineating mixed habitat classes These complementary products serve different purposes: probability maps provide confidence measures, extent maps delineate habitat boundaries, percent cover maps support quantitative analysis of habitat density patterns, and composite habitat maps represent the diversity of mixed habitat classes. Together, they provide a comprehensive understanding of seagrass and associated habitat distribution across the study area.

Seagrass beds are a dominant marine ecosystem of Tayaritja (the Furneaux Group of Islands) in the north-eastern waters off Tasmania. Historical coarse mapping has indicated extensive beds of Posidonia, Amphibolis, Heterozostera, and Zostera species, potentially comprising some of the largest and deepest seagrass extents found in temperate Australian waters. However, limited data on the distribution and ecological value of these seagrass habitats represents a significant knowledge gap in understanding Australia's wetland natural assets. This project mapped the extent, ecological composition, population structure, and blue carbon value of seagrass beds around Tayaritja. The study area focused on the coastal waters surrounding Flinders Island in the western Furneaux Group, with mapping extending from the high tide line to the depth limit of reliable optical detection (approximately 30 m), based on analysis of field data and satellite imagery capabilities in the region. The field validation component of this study involved deployment of benthic video platforms to capture imagery of seagrass beds and associated ecosystems. A field campaign deployed a Benthic Observation Survey System (BOSS) and unBaited Remote Underwater stereo-Video system (stereo-uBRUV) at approximately 400 locations to collect photoquadrats and validate remote sensing outputs. Imagery annotation was conducted in the SQUIDLE+ platform. The approach developed through this study contributed to the creation of the NESP Standard Operating Procedure (SOP) for Seagrass Mapping using Optical Remote Sensing (https://sustainabledevelopmentreform.github.io/nesp-sop-seagrass-mapping).. See the "Lineage" section of this record for full methodology of field collection techniques. See associated dataset https://doi.org/10.25959/e4s6-ge74 for habitat maps derived from field validation and remote sensing inputs.

***This record contains a subset of benthic habitat data from https://doi.org/10.25959/E4S6-GE74 (NESP MaC Project 3.6) rehosted for the purposes of the Seamap Australia collaborative project.*** Seagrass beds are a dominant marine ecosystem of Tayaritja (the Furneaux Group of Islands) in the north-eastern waters off Tasmania. Historical coarse mapping has indicated extensive beds of Posidonia, Amphibolis, Heterozostera, and Zostera species, potentially comprising some of the largest and deepest seagrass extents found in temperate Australian waters. However, limited data on the distribution and ecological value of these seagrass habitats represents a significant knowledge gap in understanding Australia's wetland natural assets. This project mapped the extent, ecological composition, population structure, and blue carbon value of seagrass beds around Tayaritja, in partnership with the Tasmanian Aboriginal Centre, as part of NESP Marine and Coastal Hub Project 3.6. The study area focused on the coastal waters surrounding Flinders Island in the western Furneaux Group, with mapping extending from the high tide line to the depth limit of reliable optical detection (approximately 30 m), based on analysis of field data and satellite imagery capabilities in the region. This metadata record specifically describes the benthic mapping component of the study. A combination of close-range remote sensing methods was used to map the extent and ecological values of seagrass beds. High-resolution satellite imagery from Sentinel-2 (10 m) sensors, combined with bathymetric LiDAR data and oceanographic variables, was used to map baseline seagrass extent and composition. A field campaign deployed a Benthic Observation Survey System (BOSS) and unBaited Remote Underwater stereo-Video system (stereo-uBRUV) at approximately 400 locations to validate remote sensing outputs, collecting field photo quadrats and rhizome cores. From these data, maps were produced showing the extent and coverage of seagrass, sand, and macroalgae, and where possible, seagrass species composition, subject to water depth and clarity constraints. See the "Lineage" section of this record for full methodology.

This dataset presents the results of a seafloor habitat modeling exercise for the 'Capes region' of the South-west Corner Marine Park, southern WA. The model classifies five broad habitat types (hereafter 'ecosystem components'): seagrass, macroalgae, sessile invertebrates, bare consolidated substrata, and bare unconsolidated substrata. Modeling was conducted at two spatial scales to assess the effectiveness of using broad-scale (~250 m) spatial covariates derived from bathymetry in mapping habitat classes and to compare the modelling outcomes with those obtained using finer-resolution input data. The fine-scale mapping focused on an IUCN II zone near Margaret River, using a seamless 5 m resolution multibeam bathymetry composite. The broad-scale mapping covered multiple IUCN zones, including the southwestern Geographe Australian Marine Park (AMP), the northwestern tip of the South-west Corner AMP, and the Ngari Capes WA State Marine Park. This component used the 250 m resolution 2023 AusBathyTopo grid from Geoscience Australia. Habitat maps were constructed using (1) the bathymetry data sources described above; (2) ground-truthing observations from stereo-BRUV and BOSS camera systems; and (3) Physical covariates, all smoothed to 5 m or 250 m resolution, for the fine- and broad-scale mapping, respectively. Source datasets are available from: • Geoscience Australia's eCat: https://dx.doi.org/10.26186/145281 (5 m multibeam bathymetry) and https://doi.org/10.26186/148758 (250 m DEM bathymetry) • Squidle+: http://squidle.org/geodata/explore (benthic imagery annotations - see also outputs from NESP MaC Project 2.4: https://doi.org/10.25959/6G5A-3G03) • AODN Portal: https://portal.aodn.org.au/search (IMOS oceanographic datasets). This analysis uses the modelling methodology developed in NESP Project 2.1, which extended the ecosystem component modelling to include all temperate Australian shelf waters at a resolution of 250 m (https://doi.org/10.25959/BVJ7-D984). Analysing the scale effects effects of spatial covarariate inputs was undertaken by NESP Project 2.3, along with exploration of visualisation options regarding prediction certainty in consultation with Parks Australia (management end-users). Further details on sampling design for ground-truthing observations and the modelling techniques are available in the NESP MaC Project 2.1 Final Report: https://www.nespmarinecoastal.edu.au/publication/improving-seabed-habitat-predictions-for-southern-australia. A description on this specific South-west Corner case study and the spatial scale analysis is described in the NESP MaC Project 2.3 Final Report: https://www.nespmarinecoastal.edu.au/publication/improving-knowledge-transfer-to-support-australian-marine-park-decision-making-and-management-effectiveness-evaluation. A selection of mapping (WMS) services are listed in the 'Downloads & Links' section of this record. See the 'Lineage' section for a full description of the data packages available for download, and for more visualisation options.

The main aim of this research program was to determine the potential for reducing the density of urchins to encourage the return of seaweeds and an improvement in urchin roe quality and quantity from remaining urchins. Tasmanian Sea Urchin Developments used two widely-separated sub-tidal experimental lease areas. One of these areas was at Meredith Point, on the east coast, and the other at Hope Island, on the south coast. Both sites had been subject to some overgrazing by urchins. At Meredith Point, the study area was divided into plots containing urchins at three densities: artificially enhanced, continually harvested and control (undisturbed). At Hope Island, controlled clearings of urchins and limpets from barrens areas were conducted. Recovery of vegetation was monitored as well as urchin roe quality and quantity. The data represented by this record was collected at Meredith Point.