Directorate E: Sectoral and regional statistics Unit E-4: Regional statistics and geographical information LUCAS 2018.

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1 EUROPEAN COMMISSION EUROSTAT Directorate E: Sectoral and regional statistics Unit E-4: Regional statistics and geographical information Doc. WG/LCU 52 LUCAS 2018 Eurostat Unit E4 Working Group for Land Cover and Land Use Statistics Meeting of 17 and 18 November 2016 Luxembourg BECH Building Room Quetelet starting on 17 November at 09h30 and planned to finish on 18 November at 13h00 CHAIRED BY: MR GUNTER SCHÄFER No interpretation, English only

2 1 INTRODUCTION Future LUCAS surveys were discussed in the framework of the Task Force on "LUCAS 2018 and beyond"; the assessment of user needs and requirements collected from Commission services related to land cover and land use information confirmed the need for aggregated statistics and the priority use of LUCAS in-situ information which provide valuable input for modelling. In particular the review of DG needs, through questionnaires and dedicated workshops prepared in cooperation with national experts, confirmed the general approach taken for the LUCAS survey. Moreover the need for specific analyses through dedicated additional modules, such as specific soil collection and/or dedicated modules for grassland have been identified and specified. The technical and financial preparation for LUCAS 2018 started in Q and required a tight coordination of the user needs; survey 2018 is co-financed by DG AGRI, DG CLIMA, DG ENV and DG GROW. A revised stratification of Master Sample (LUCAS grid 2 by 2 Km) was launched. Content wise the survey 2018 includes pilot data collection concerning: 1) a Grassland module whose technical specifications have been circulated among MS, 2) new Soil Modules developed in tight cooperation with JRC; final documents expected by end October. In addition, some parameters of the core LUCAS are being reviewed to better adapt it to Copernicus needs. Sample design for LUCAS 2018 requires specific attention. 2 STRATIFICATION OF THE LUCAS MASTER The current LUCAS survey design is based on a two stage sampling process: i) First Phase (Base grid): The LUCAS base is obtained by using a 1 Km 2 grid (resulting from the INSPIRE recommendations) with a systematic spatial sampling design 1 which includes around points in the entire European Union territory. ii) First Phase (Master grid): The LUCAS master is a subset of the base, comprising around N= points (corresponding to a 2 Km 2 grid covering the EU-28 territory, also systematically selected). Each of these points is classified into k land cover categories (the strata) on the basis of photointerpretation of aerial photos or satellite images. In 2005 these points in the master were stratified into 7 aggregated strata. iii) Second Phase (Sample): The final field sample is a sub-selection of the master. A sample of n points, out of N, is selected by strata and by NUTS2 and the n points are visited in order to determine the land cover and land use at a more detailed level. In such framework, the quality and timeliness of the stratification of the First Phase Master grid is very important for the accuracy of the statistical estimates. A revision of the existing LUCAS stratification, done using a recent image coverage of known positional accuracy, that covers also the countries presently missing in the master grid, is required to improve the quality of the sampling for the next LUCAS surveys. 1 The point selection is referred to as Systematic Spatial Sampling if the total area under study is divided into quadrants, the first point is randomly selected in a quadrant and the remaining N-1 points are placed in the same position within the corresponding quadrants. 2

3 Therefore an open call for tender has been launched in 2016 with the objective to classify a selection of points of the master grid of LUCAS 2018 (a 2x2 Km grid of points which comprises a total of points over the 28 EU member states) into one of 10 strata and one parameter, according to the instructions provided. The classification in strata is based on land cover characteristics and covers the following classes: arable land, permanent crops, grass, wooded areas, shrubs, bare surface (includinf low or rare vegetation), artificial constructions and sealed areas, transitional and coastal water and "impossible to photointerpret" (e.g. clouds ). Kick off meeting of the project will take place on 25 November. The project will last maximum 8 months. 3 NEW SPECIFIC MODULES IN LUCAS 2018 Based on the user needs surveys with DGs, that took place in (questionnaire, bilateral meetings and dedicated workshops) the specific modules of the LUCAS field survey have been modified. Major drivers for these integrations are climate change and ecosystem services. The specific module on transects has been dropped, the specific module on soil has been extended and a new module for grassland has been introduced. Some specific elements for a better integration of the Copernicus needs have been added to the general survey. 3.1 Soil module The soil module in addition to the basic module - will also include a test run for soil biodiversity, the assessment of bulk density and an evaluation of the peat layers. 9,000 bulk density samples (records the weight of soil for a given volume required to calculate soil carbon stops increasing bulk density may be indicative of compaction; bulk density increases with compaction and tends to increase with depth); 1,000 samples for soil biodiversity; thickness of organic horizon in peat soils (c, 2,000 samples already identified in 2009/2015 important for climate change assessments); evidence of soil erosion. A detailed description is provided by the technical report of the JRC n the annex. 3.2 Pilot Grassland The goal of the new module on grassland is to assess the type of grassland, the intensity of the use and the ecological conditions. To this end an assessment of key flowering species and a selection of specific site parameters should be done. The grassland module has been developed by experts taking into account the different climatic and biological conditions (Adaptation of the Biogeographic regions of the EEA), the different site conditions and the possibility to identify key species by an average LUCAS surveyor. The full documentation is available in the annex. Being this a new development it is foreseen to implement a test version in 2018 on some 3800 points. 2 Points visited in the latest LUCAS surveys were excluded from the project. 3

4 3.3 Copernicus As concerns the adaptation to Copernicus this mainly consists in using a specific window of observation of 50 m. The extend of the land cover at the LUCAS point and the next land cover will be registered in the 4 cardinal directions up to a maximum distance of 50 m. Copernicus also requires some fine tuning of the LUCAS land use classification, e.g. separate U361: Amenities, leisure / museum and culture, Exclude combination G12/U111, collect information on airport/port for U317 Logistics & storage 4 SAMPLE 2018 LUCAS is a multipurpose platform for agro-environmental and landscape policy purposes. LUCAS scope includes a core part which is stable and the so called additional modules such as: 1) land covers transition and linear features in the transect (a 250 meter walk direction East) and 2) top-soil sample. The strength of the survey is the specific set up that allows, once on the spot, the collection of different variables (ad-hoc modules) according to the policy needs in different surveys. Commission DGs are the main final clients of the data collected in the LUCAS survey (micro data), and have expressed need for a LUCAS data collection in 2018 with a number of new requirements: 1) a new Soil package [ top soil, of which for bulk density, for peat thickness and frozen samples for biodiversity] 4 2) a Pilot on Grassland species on points. 3) adaptation of the sample size to the Copernicus needs (densification of sample in selected areas). On average 2/3 of the points from the previous survey are kept in the field sample, but as the aim of LUCAS is also to monitor the changes in landscape it may not be worth visiting every survey areas which are likely not changing. In addition as LUCAS is a field survey the accessibility of the point has to be taken into account. Some areas cannot be reached because of natural features (for example high mountainous area) or because restricted access (private properties or military areas). The exclusion from target survey population of difficult to access areas causes bias in the final estimates; the exclusion of points below certain elevation and difficult to be accessed due to road distance and steepness, becomes critical in particular in mountain areas or remote islands. For survey 2015 Eurostat identified corrective measures for the statistical treatment of the areas excluded from the field survey for accessibility reasons, combining field survey with Photo Interpretation approach and ex-post added Photo interpreted points to the field sample. Given all the requirements and the lesson learned, the sample design for LUCAS 2018 requires a tight coordination of the user needs and a global strategy for the field part and the Photo Interpretation part. A methodological contract will be launched to improve the quality of the current survey design and to propose a new global survey design for LUCAS 2018 with the following requirements: It covers all territory of EU including both field part and photo interpreted sample.

5 It takes into account accessibility of the single points, possibly revising the accessibility criteria used so-far. It takes into account the propensity to change of land cover. It fulfils the requirements and instructions for the new elements of the LUCAS 2018 survey (soil package, grassland module and Copernicus adaptation). It ensures as much as possible comparability with the previous LUCAS surveys. It allows solid estimation of main variables at the lowest regional level possible 5 OPEN ISSUES Risk analysis and mitigation actions concerning soil and access to private land should be foreseen in cooperation with Member States. 5