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General typology of grassland ecosystems We consider Grassland ecosystem as a natural or seminatural vegetation type. It could be part of farm holdings like pastures, meadows, uncultivated lands, etc. Grassland ecosystems include lands used for production of natural resources for animal consumption as food, for production of fiber or for livestock services. 2
Typology of ecosystems in Bulgaria Level 1 and Level 2 Following the MAES (2013) classification, Grassland ecosystems are Ecosystem type at Level 2. Level 1 Main ecosystem types Terrestrial Fresh water Marine Level 2 Ecosystem types Cropland Heathland and shrub Sparsely vegetated land Woodland and forest Grassland Urban Wetlands River and lakes Marine 3
Terrestrial Grassland FINANCIAL MECHANISM OF THE EUROPEAN ECONOMIC AREA EEA FM 2009-2014 Grassland ecosystem typology Level 3 The proposed typology of Grassland ecosystems corresponds with the EUNIS Level 2 chosen to be the base for our mapping and assessment approach. Five grassland ecosystem subtypes are selected at Level 3. Level 1 Level 2 Level 3 E1. Dry grasslands E2. Mesic grasslands E3. Seasonally wet and wet grasslands E4. Alpine and subalpine grasslands E6. Inland salt steppes 4
Grassland ecosystem typology Mapping at Level 3 М 1:1 500 000 5
Grassland ecosystems in Bulgaria Grassland ecosystems typology 301. Dry grasslands 302. Mesic grasslands 303. Seasonally wet and wet grasslands 304. Alpine and subalpine grasslands 305. Inland salt steppes Total area within NATURA 2000: 5 691 sq. km Total area outside NATURA 2000: 6 695 sq. km. The total number of polygons outside NATURA 2000: >120 000 - with area < 1.0 ha: around ¼ of polygons DD MM YYYY, City, Event Place Type of event 6
Grassland ecosystem typology DRY GRASSLANDS Dry lands dominated by grasses or herbs mostly with low productivity but high species richness, developed on places of termophile oak forests. They could be open or closed, arid, floristically rich, steppe-like, typically with species of genera Stipa and Festuca. In Bulgaria within this group are included also communities dominated by Dichantium ischaemum, Chrysopogon gryllus and Poa bulbosa. 7
DRY GRASSLANDS Distribution in Bulgaria М 1:1 500 000 8
Grassland ecosystem typology MESIC GRASSLANDS Lowland and montane mesotrophic and eutrophic pastures and hay meadows. They are generally more productive than dry grasslands. The soils are moistened by underground or surface water supplied by slope runoff. Species richness is generally high. Typical dominant species are Arrhenatherum elatius, Festuca pratensis, Alopecurus pratensis, Trisetum flavescens. 9
MESIC GRASSLANDS Distribution in Bulgaria М 1:1 500 000 10
Grassland ecosystem typology SEASONALLY WET AND WET GRASSLANDS Grasslands of occasionally flooded river terraces, of depressions where rain water collects. Very typical are humid meadows rich in clover (Trifolium spp.), mostly developed below the montane level. 11
SEASONALLY WET AND WET GRASSLANDS Distribution in Bulgaria М 1:1 500 000 12
Grassland ecosystem typology ALPINE AND SUBALPINE GRASSLANDS Primary and secondary grass- or sedge- dominated communities of the alpine and subalpine levels. Part of these grasslands form dense, closed, chionophilous grasslands of acid substrates at the 1800-2500 m of high mountains. Particular group are alpine and subalpine grasslands of base-rich soils. 13
ALPINE AND SUBALPINE GRASSLANDS Distribution in Bulgaria М 1:1 500 000 14
Grassland ecosystem typology INLAND SALT STEPPES Salt steppes and their associated salt-tolerant herbaceous communities and other sub-halophyte plant communities. In Bulgaria large areas of halophyte vegetation occurs in south-eastern parts of the country on plain territories with salty soils. Dominate species from genera Puccinelia, Camphorosma, Crypsis, Elymus, Artemisia, etc. 15
INLAND SALT STEPPES Distribution in Bulgaria М 1:1 500 000 16
Grassland ecosystem typology Interpretation keys Interpretation keys are aimed at explaining the features of all five grassland ecosystem subtypes. They describe the main characteristics of Bulgarian grassland subtypes. In order to be easily interpreted and applied by a wide range of specialists, interpretation keys comprise only indicative and easily recognizable parameters. 17
GIS Activities Mapping of grassland ecosystems Creation of a model for defining grassland subtypes Creation of GIS database, including: GIS layer of grassland ecosystem subtypes; GIS data for mapping of ecosystem condition and services GIS data presenting final results Validation Creation of thematic maps of grassland ecosystem subtypes Creation of Web GIS Application Transfer Grassland Database to the Database, common to all 9 ecosystems. 18
Mapping of grassland ecosystems The main aims Mapping of grassland ecosystems out of NATURA 2000 Sites Coverage 100 % of grasslands out of NATURA 2000 Sites Minimum mapping unit 0,25 ha Thematic and geometric accuracy 85% Classification of grassland ecosystems in 5 subtypes according EUNIS 301 - Dry grassland 302 - Mesic grassland 303 - Seasonally wet and wet grasslands 304 - Alpine and subalpine grasslands 305 - Inland salt steppes NATURA 2000 Network Total number of grassland polygons: over 120 000 Total area of grassland ecosystems: over 6000 sq.km 19
Mapping of grassland ecosystems Processing chain Step 1 Examination of available national databases, related to mapping of grassland ecosystems Cadastre, Map of Restored Property, Land Parcel Identification System (LPIS), CORINE Land cover, etc. Step 2 Visual inspection and digitalization based on the latest available aerial photography Geometry correction of existing grassland polygons, according to Methodology requirements; Digitize new grassland polygons, not part of existing ones. Step 3 check for gaps and overlaps between the 9 ecosystems. Step 4 terrain verification and validation of results Step 5 the final result is one polygon layer in which each individual polygon has a unique identifier (ID) to which thematic information have been assigned (indicators for ecosystem condition and services) 20
Mapping of grassland ecosystems sources of information Cadastre, Map of Restored Property CORINE Land Cover LPIS 21
Mapping of grassland ecosystems The Beginning LPIS a starting point for mapping grassland ecosystems Pros Very good geometric accuracy LPIS is digitized based on up-to date aerial photography Cons Classification of LPIS polygon according their permanent use, does not allow to determine unequivocally whether it concerns a grassland ecosystem (for example areas around settlements, shrubs and grasslands, mixed landuse, bare and eroded areas - in all of them are found a lot of grasslands) The use of LPIS has led to an initial set of hundreds of thousands of potential grass polygons that have been checked with aerial photography and decided whether they are grassland; In many of grassland polygons from LPIS were found areas, part of other ecosystems - correction in the shape. 22
Mapping of grassland ecosystems The diversity of grassland ecosystems in different parts of Bulgaria creates different precedents for their mapping Risk for subjective opinion The main question is: grassland or arable land? Allowable area of shrub cover, above which a polygon can't be considered as grass 23
Mapping of grassland ecosystems Mapping of grassland ecosystems should be done on the most up-to-date images, from the same year, covering the territory of the whole investigated territory. The reason: Under the influence of natural and anthropogenic factors, grassland ecosystems are changing their coverage and this is visible on aerial photographs over a period of several years. 2006 2013 24
Mapping of grassland ecosystems The loss of grassland is related to shrub expansion; conversion into arable land or into urban area; The process of change has not only a negative sign for grasslands agricultural subsidies encourage farmers to maintain grasslands. The change is quick and use of up-to-date data for grassland mapping play a crucial role. The answer is usage of satellite images Landsat, NDVI Sentinel 2 visible (10 m) and infrared (20 m) As a result of this project, we have mapped grassland ecosystems outside of NATURA 2000 sites, with accuracy and detail that have not been done in Bulgaria so far. 25
Grassland subtypes: Model for grassland subtypes Step 1: Use of available data 6 000 plots, for which there is accurate information about ecosystem subtype Terrain data from 2016 Bulgarian Phytocoenosis Database (GIVD ID: EU-BG-001) Balkan Phytocoenosis Database (GIVD ID: EU-00-019) Balkan Database for Dry Grassland (GIVD ID: EU-00-013) Inventory of grassland in Bulgaria (PINMATRA/2001/020), 2002-2004 Most of available information about grassland ecosystems refers to the areas part of NATURA 2000 sites 26
Grassland subtypes: Model for grassland subtypes Step 2: Creation of a model for defining grassland subtypes Determine different variables Elevation Slope Accumulation Soils Distance to water bodies Etc. Good results for dry, seasonally wet and wet and alpine grassland subtypes The main difficulty is to make difference between dry and mesic grasslands 27
Grassland subtypes: Model for grassland subtypes Difference between dry and mesic grassland ecosystems: It can not be established by visual interpretation of aerial photography in visible spectrum Use of satellite images Landsat NDVI mosaic for 3 months may, june, july. Disadvantage: The mosaic was made from images from different years; Resolution - 30 m There are no trends in NDVI values at national level for different grassland subtypes. A regionalization method based on phytogeographical regions has been adopted. The available data for grassland subtype (6000 samples) is used. Established difference between dry and mesic grasslands at region level. We consider using this approach will give good results for determining grassland ecosystem subtypes 28
Grassland Database Combine available data for grassland ecosystems GIS layer of grassland ecosystem subtypes GIS data for mapping of ecosystem condition and services Data from phytocoenosis databases Other GIS data LPIS, soil map, geological Map, DEM, maps of water and wind erosion, etc. Data from national public registers the most of them were not in GIS format Processed data, which are processed and can be used directly for calculation of indicators for ecosystem condition and services Result data, GIS data presenting final results Models for automatic calculation 29
Grassland Ecosystem Database Grassland ecosystem one polygon layer Grassland ecosystem subtypes Data for administrative structure District, Municipality, Populated place (NUTS 3, LAU 1, LAU 2) Phytogeographical regions Base morphometric data Altitude, Aspect, Slope, Area NDVI values for vegetation period Data sources EcoUnit_ID unique identifier for a individual grassland polygon 30
Grassland Ecosystem Database Indicators for condition and services The final results for each parameter/indicator are stored in separate table. There is information about: The value of the parameter / indicator The accuracy with which it was calculated Score in 5 point scale (1 very bad 5 very good) The source of the data, which are used for calculation Data validity From-To Date The link between the GIS layer of grassland and indicator tables is done through the EcoUnit_ID field 31
Web GIS FINANCIAL MECHANISM OF THE EUROPEAN ECONOMIC AREA EEA FM 2009-2014 An overview of the distribution of the grassland ecosystem types View the assessment of each indicator and the services provided Query http://grass.wgs.resac-bg.org/map/ 32
Grassland Ecosystem Database Methodology Database 9 ecosystems, 1 database, managed by Bulgarian Executive Environment Agency Specialized database for Grassland Ecosystem Methodology Database Unifying the data of the nine ecosystems 33
THANK YOU FOR YOUR ATTENTION! http://grasslands-ecoservices-bg.eu 34