Thomas Oliver Robert ollie@projectseagrass.org 0009-0000-1636-9492 Unsworth Richard K F r.k.f.unsworth@swansea.ac.uk Swansea University https://www.swansea.ac.uk https://ror.org/053fq8t95 2026 Spatial, Light, Temperature and Seagrass Planting and Monitoring record data from North Wales 2023-2024 dataset bundled publication https://doi.pangaea.de/10.1594/PANGAEA.996148 2026-07-24T12:14:17 This data package contains restoration, monitoring and in-situ environmental data collected between February 2023 and October 2025 in support of a study on the resilience of restored seagrass (Zostera marina) meadows to marine heatwave exposure in North Wales, United Kingdom (Thomas et al., 2026). Seagrass was planted at four intertidal sites along the Llŷn Peninsula and Ynys Môn using directly injected seeds, hessian bags and seed balls; planting locations were surveyed with a differential Global Positioning System (dGPS) receiver, producing spatial point and polygon records of the planted areas. Restoration success was subsequently assessed through repeated intertidal quadrat surveys recording shoot and reproductive shoot density, rhizome presence, canopy height, percentage cover of seagrass, epiphytes and algae, and sediment redox potential, pH and temperature, measured using a portable multiparameter meter. In-situ seawater/intertidal temperature and light intensity were additionally recorded at 30-minute intervals over one month in May 2024 using a fixed temperature/light data logger. These restoration and monitoring records were combined with satellite-derived sea surface temperature and marine heatwave indicator data from the E.U. Copernicus Marine Service (doi:10.48670/moi-00054, doi:10.48670/moi-00055) to evaluate how marine heatwave exposure affected the establishment and persistence of a restored seagrass meadow. The package comprises four data types - in-situ light and temperature logger data, spatial point and polygon data of planting locations, seagrass planting records, and seagrass monitoring records - each published here as an individual dataset. Thomas Oliver Robert ollie@projectseagrass.org 0009-0000-1636-9492 Patterson Bridget M 0009-0000-8621-2247 Rowland Caroline Berthou Ségolène 0000-0002-9164-0841 Worsfold Mark 0000-0003-0722-4456 Yates Emily 0009-0000-0776-4466 Keen Charlotte den Haan Stijn Unsworth Richard K F r.k.f.unsworth@swansea.ac.uk 2026 Marine heat waves endanger the rebuilding of marine life journal article Environmental Research Letters 21(10) https://doi.org/10.1088/1748-9326/ae6d17 104019 2018 Atlantic - European North West Shelf - Ocean Physics Analysis and Forecast dataset Mercator Ocean International https://doi.org/10.48670/MOI-00054 2019 Atlantic - European North West Shelf - Ocean Wave Analysis and Forecast dataset Mercator Ocean International https://doi.org/10.48670/MOI-00055 -4.587140999999974 -4.319450833000019 52.86612995 53.320517 -4.446424953391386 52.95048211161729 2023-02-20T00:00:00 2025-10-08T00:00:00 SORNW Seagrass Ocean Rescue North Wales https://www.wwf.org.uk/what-we-do/projects/north-wales-seagrass-ocean-rescue World Wide Fund for Nature International WWF http://www.wwf.org/ https://ror.org/001pprn90 Natural Environment Research Council NERC http://www.nerc.ac.uk/ https://doi.org/10.13039/501100000270 NE/V016385/1 The National Lottery Heritage Fund HLF https://www.heritagefund.org.uk/ https://doi.org/10.13039/501100016135 NL-21-00035 5 CC-BY-4.0 Creative Commons Attribution 4.0 International https://creativecommons.org/licenses/by/4.0/ Type of study | Study type | Identification | ID | Project | Site | Site index code | Site ind | Region | Area/locality | Area | Planting method | Plant method | Planting Date | Date/time start, experiment | Date/time start exp | Year of observation | Year obs | Species, unique identification | Species UID | Intertidal / subtidal | Condition | Cond | Sediment type | Sediment | Plot / transect | Experimental plot | Plot dimensions (shore-to-sea) planted area: 1 m² quadrat | Distance, shore to sea | Dist shore sea | Plot dimensions (parallel to sea), planted area: 1 m² quadrat | Distance, parallel to sea | Dist parallel sea | Planted area | Targeted | Zostera marina, seeds | Z. marina seeds | Planted by hand | Zostera marina, seeds per plot | Z. marina seeds plot | Manual count/volume measure during planting | Zostera marina, seed balls per plot | Z. marina seed balls plot | Zostera marina, hessian bags per plot | Z. marina hessian bags plot | Coordinate Description | Sample comment | Individual dGPS-coordinates recorded per plot/point at the time of planting. | Easting, local | East local | Differential Global Positioning System (DGPS), Trimble DA2 | Northing, local | North local | During planting | Sea level, relative | Sea lev rel | dGPS during planting | Accuracy, vertical | Accuracy V | Accuracy, horizontal | Accuracy H | Planter | Investigator | Comment | Monitoring reference database | Monitoring DB | Sample ID | Temperature, water | Temp | Temperature logger, Onset, HOBO Pendant MX2202 | Light intensity | Binary Object | Binary | Principal investigator | PI | Planted (yes/no) | Planted (y/n) | Monitoring identification | Monitoring ID | Month | Monitoring method | Monitor method | Sampling strategy | Sampling strat | Monitoring area | Observed | Zostera marina, shoots | Z. marina shoots | Manual quadrat count | Z.marina shoots | Depth, redox | Depth redox | Ruler stick | Worm casts | 1 | Canopy height | Canopy h | 2 | 3 | Epiphytes, cover | Epiphytes cov | Visual estimation | Algae, cover | Algae cov | Blackening | Bleaching | Oxidation reduction (RedOx) potential | Eh | Multiparameter probe, HANNA Instruments, HI-98191 | pH | Sediment surface temperature | Sed surf temp | Lithology/composition/facies | Lithology | dGPS | Global Positioning System (GPS), Garmin, GPSmap 60 CSx Field experiment In-situ Monitoring restoration method12443 method17225 method19056 method19449 method19450 method19451 method19452 method4760 param102259 param132665 param141184 param145013 param146419 param150355 param15373 param155369 param15652 param1570 param16065 param165674 param168472 param18011 param184312 param184313 param184731 param185520 param2834 param47 param48491 param500828 param505000 param510679 param516119 param533102 param567424 param567425 param567426 param567427 param567428 param567429 param567430 param567431 param567432 param567433 param567434 param567435 param567436 param567437 param567438 param567439 param567443 param567444 param567445 param567449 param567450 param567452 param7056 param7151 param717 param764 param88037 param97989 pi106706 author106706 author118504 author118506 author118507 author118508 author118509 author118510 author118511 author118512 award5164 award5167 funder1797 funder22897 geocode1599 geocode1600 geocode1601 inst22896 inst2617 journal5064 license21 project5123 ref140776 ref140777 ref140778 term38842 term47611 term50572 term52587