The vector grid system provides a spatial and statistical infrastructure that allows the integration of environmental and socio-economic data. Its use allows the crossing of different spatial data within the same grid units. Project results obtained using this grid system can be more easily linked. This system of grids forms the geographic and statistical infrastructure of the [Southern Quebec Land Accounts] (https://statistique.quebec.ca/fr/document/comptes-des-terres-du-quebec-meridional-regions-administratives-et-provinces-naturelles) of the Institut de la Statistique du Québec (ISQ). It forms the geospatial and statistical context for the development of ecosystem accounting in Quebec. **In order to improve the vector grid system and land accounts in southern Quebec and to better anticipate the future needs of users, we would like to be informed about their use (field of application, purposes of use, territory, association with other products, etc.). You can write to us at maxime.keith@stat.gouv.qc.ca **. This grid system allows the spatial integration of various data relating, for example, to human populations, the economy or the characteristics of the terrain. The ISQ wishes to encourage the use of this system in projects that require the integration of several data sources, the analysis of these data at different spatial scales, and the monitoring of these data over time. The fixed geographical references of the grids simplify the compilation of statistics according to different territorial divisions and facilitate the monitoring of changes over time. In particular, the grid system promotes data consistency at the provincial level. The spatial intersection of the grid and the spatial data layer to be integrated allows the underlying information of the layer to be transferred within each cell of the grid. In the case of the Southern Quebec Land Accounts, the spatial intersection of the grid and each of the three land cover layers (1990s, 2000s, and 2010s) made it possible to report the dominant coverage within each grid cell. The set of [Southern Quebec Land Accounts matrix files] (https://www.donneesquebec.ca/recherche/fr/dataset/comptes-des-terres-du-quebec-meridional-changement-de-la-couverture-terrestre) is the result of this intersection. **Characteristics: ** The product includes two vector grids: one formed of 1 km² cells (or 1,000 m on a side), which covers all of Quebec, and another of 2,500 m² cells (or 50 m on a side, or a quarter of a hectare), which fits perfectly into the first and covers Quebec territory located south of the 52nd parallel. Note that the nomenclature of this system, designed according to a Cartesian plan, was developed so that it would be possible to integrate cells with finer resolutions (up to 5 meters per side). In its 2023 update, the 50 m grid system is broken up into 331 parts with a side of 50 km in order to limit the number of cells per grid part to millions and thus facilitate geospatial processing. This grid includes a total of around 350 million cells or 875,000 km2. It is backwards compatible with the 50 m grid released by the ISQ in 2018 (spatial structure and unique identifiers are identical, only the fragmentation is different). **Attribute information for 50 m cells: ** * ID_m50: unique cell code; * CO_MUN_2022: geographic code of the municipality as of January 2022; * CERQ_NV2: code of the natural region of the Quebec ecological reference framework; * CL_COUV_T00, CL_COUV_T01a, CL_COUV_T01b, CL_COUV_T02: coverage class codes Terrestrial maps from the years 1990, 2000 and 2010. Note: the 2000s are covered by two land cover maps: CL_COUV_T01A and CL_COUV_T01B. The first inventories the land cover prior to the reassessment using the 2010s map, whereas the second presents the land cover after this reassessment process. **Complementary entity classes: ** * Index_grile50m: index of parts of the grid; * Decoupage_mun_01_2022: division of municipalities; * Decoupage_MRC_01_2022: division of geographical MRCs; * Decoupage_ra_01_2022: division of administrative regions. Source: System on administrative boundaries [SDA] of the Ministry of Natural Resources and Forests [MRNF], January 2022, allows statistical compilations to be made according to administrative divisions hierarchically higher than municipalities. * Decoupage_CERQ_NV2_2018: division of CERQ level 2, natural regions. Source: Ministry of the Environment, the Fight against Climate Change, Wildlife and Parks [MELCCFP]. **Geospatial processes delivered with the grid (only with the high FGDB data) :** * ArcGIS ModelBuilder allowing the spatial intersection and selection of the dominant value of the geographic layer to populate the grid; * ModelBuilder allowing the statistical compilation of results according to different groupings. Additional information on the grid in the report [Southern Quebec Land Accounts] (https://statistique.quebec.ca/fr/fichier/comptes-des-terres-du-quebec-meridional-edition-revisee.pdf#page=46) published in October 2018 (p. 46). View the results of the Southern Quebec Land Accounts on the [interactive map] (https://statistique.quebec.ca/cartovista/comptes_terres/index.html) of the Institut de la Statistique du Québec.**This third party metadata element was translated using an automated translation tool (Amazon Translate).**