National Inventories of Landscapes in Sweden: NILS Inventory 2003–2020

Data Records

The data in this sampling event resource has been published as a Darwin Core Archive (DwC-A), which is a standardized format for sharing biodiversity data as a set of one or more data tables. The core data table contains 17,990 records.

1 extension data tables also exist. An extension record supplies extra information about a core record. The number of records in each extension data table is illustrated below.

This IPT archives the data and thus serves as the data repository. The data and resource metadata are available for download in the downloads section. The versions table lists other versions of the resource that have been made publicly available and allows tracking changes made to the resource over time.

Versions

The table below shows only published versions of the resource that are publicly accessible.

How to cite

Researchers should cite this work as follows:

Hedenås H (2026). National Inventories of Landscapes in Sweden: NILS Inventory 2003–2020. Version 1.2. National Inventories of Landscapes in Sweden, Department of Forest Resource Management, SLU. Samplingevent dataset. https://www.gbif.se/ipt/resource?r=nils-event&v=1.2

Rights

Researchers should respect the following rights statement:

The publisher and rights holder of this work is National Inventories of Landscapes in Sweden, Department of Forest Resource Management, SLU. To the extent possible under law, the publisher has waived all rights to these data and has dedicated them to the Public Domain (CC0 1.0). Users may copy, modify, distribute and use the work, including for commercial purposes, without restriction.

GBIF Registration

This resource has been registered with GBIF, and assigned the following GBIF UUID: 133c7d7c-81cf-4114-bf12-30c5d1a57e0d.  National Inventories of Landscapes in Sweden, Department of Forest Resource Management, SLU publishes this resource, and is itself registered in GBIF as a data publisher endorsed by GBIF Sweden.

Keywords

Samplingevent; Observation

Contacts

Geographic Coverage

NILS data are collected across the whole of Sweden, including alpine, lowland, forested, grassland, and wetland landscapes. The sampling design ensures national representativeness, covering both protected and unprotected areas.

Temporal Coverage

Project Data

The NILS programme is to describe the state, distribution, and long-term changes of terrestrial habitats in Sweden. By monitoring biodiversity, landscape composition and structure, and land-use impacts, the programme provides essential information for assessing habitat quality, following biodiversity trends, supporting conservation management, and meeting national and EU-level environmental reporting and policy needs.

The personnel involved in the project:

Sampling Methods

The Alpine, Deciduous Forest, Grassland and Wetland Inventories apply a unified methodological framework designed to monitor landscape composition and habitat conditions across Sweden. The methodology is structured to support long-term, repeatable data collection while remaining flexible enough to include both common and rare habitat types. All NILS inventories follow a hierarchical, two-phase sampling design that links remote sensing–based classification with targeted field surveys. For more details on the hierarchical sampling structure see Step Descriptions. Throughout the program, the hierarchical sampling structure allows inventories of different density to be nested within the same national framework. Remote-sensing classifications ensure that non-relevant areas remain part of the statistical sample even when not visited in the field, supporting unbiased national estimates of habitat distribution and change.

Method step description:

1. In Phase 1, the primary sampling units (“tracts”) are selected from a national sampling frame consisting of all 1 × 1 km grid cells containing land or freshwater within Sweden. Tracts are chosen using coordinated and balanced sampling procedures, ensuring broad spatial representation across environmental gradients. Once selected, each tract contains a systematic arrangement of circular sample plots, which form the basis for Phase 2.
2. Phase 2 consists of two steps. Phase 2 - Step 1 is a remote-sensing–based classification of all sample plots within each tract. Depending on the inventory, this step may rely on manual aerial photo interpretation, automated model-based predictions, or a combination of both. The purpose of this step is to identify plots where target habitats are likely to occur and to exclude plots or entire tracts that certain lack such habitats. Plots are assigned to selection classes that determine their eligibility and priority for field surveys.
3. Phase 2 - Step 2 consists of conducting field surveys in the subset of plots selected from Step 1. The selection is random but stratified by the classification results, giving all potentially relevant plots a non-zero probability of inclusion. This design allows rare habitats to be sampled at higher density while keeping overall field effort feasible. Field teams collect detailed information on vegetation structure, species composition, and habitat condition, enabling refined classification and ecological assessment.

Bibliographic Citations

1. Ståhl, G., Allard, A., Esseen, P.-A., Glimskär, A., Ringvall, A., Svensson, J., Sundquist, S., Christensen, P., Gallegos Torell, Å., Högström, M., Lagerqvist, K., Marklund, L., Nilsson B. & Inghe O. 2011. National Inventory of Landscapes in Sweden NILS-scope, design, and experiences from establishing a multiscale biodiversity monitoring system. Environmental Monitoring and Assessment, 173(1–4), 579–595 https://doi.org/10.1007/s10661-010-1406-7
2. Esseen, P. A., Glimskär, A., Ståhl, G., & Sundquist, S. 2007. Field instruction for National Inventory of Landscapes in Sweden, NILS, year 2007 . Umeå. SLU, Department of Forest Resource Management. https://publications.slu.se/?file=publ/show&id=22786&lang=en

Additional Metadata