The spatial data contribution has to go through 5 sequential steps:
Choose the spatial topic
Choose the spatial layer
Check the requirements of the targeted spatial layer
Prepare the data
Upload the data
Choose the spatial topic:
You can contribute spatial data in NELGA LDH portal in one or more of the following spatial topics:
1. Land Tenure
2. Cadastral Map
3. Land Cover
4. Mineral Tenure
5. Land Conflict
6. Land use
For instance, if You want to contribute cadastral related spatial data, then the data has to be contributed in the “Cadastral Map” topic.
Choose the spatial layer
You have to choose the spatial layer of which their contributed spatial data fits. The following table shows a list of spatial layers for each spatial topic.
Check the requirements of the targeted spatial layer
The data has to be uploaded in a specific schema that makes sense in the context of every spatial topic and layer. In this regard, a data schema has been designed specially for every spatial layer. The schema of the targeted category must be followed.
Land tenure
land_tenure
The land_tenure spatial layer schema consists of 6 columns as shown in the following table and the following ERD diagram.
Cadastral_zoning layer
The schema for this spatial layer is designed to contain cadastral zones data. Cadastral zones can be defined as intermediary areas (municipalities, sections, blocks, etc.) for example. Cadastral zones are hierarchical areas. For instance, municipalities are higher in hierarchy than sections and contain sections. On the other hand, sections are higher in hierarchy than blocks and contain blocks.
The purpose of having cadastral zones is to divide the national administrative units into cadastral parcels. Though, a cadastral parcel should belong to the lowest cadastral zone level in the national cadastral hierarchy levels of zones that contain it spatially.
Please note that in the following ER Diagram there are 3 spatial layers with the following names:
cadastral_zoning_lvl1
cadastral_zoning_lvl2
cadastral_zoning_lvl3
The previous table represents a blueprint for these layers schemas. The only difference between these layers is that every layer schema is designed to contain the zones of only one level. For instance, cadastral_zoning_lvl1 layer would only contain the cadastral zones which belong to the highest level of the national cadastral hierarchy levels of zones. On the other hand, cadastral_zoning_lvl3 layer would only contain the cadastral zones which belong to the lowest level of the national cadastral hierarchy levels of zones.
cadastral_parcel layer
Cadastral parcels are areas which are defined by land registration authorities and can be owned or benefited from by individuals, authorities, organizations, etc. [1]. The data of which category can be stored and retrieved in NELGA LDP as vector data according to the following schema.
Land Cover
land_cover (vector) Layer
Land cover data can be uploaded in two different spatial data types, vector and raster.
Every vector land cover feature represents a land cover unit. A land cover unit is a homogeneous land cover area that can be categorized in one of the following main five categories:
Artificial surfaces
Agricultural areas
Forest and semi natural areas
Wetlands
Water bodies
B. land_cover (raster) Layer
land_cover (raster)
While preparing the land cover raster image, the following colors schema has to be followed for the five main categories:
Mineral Tenure
mineral_parcel
Land Conflict
Land conflict data can only be shown in two different spatial topics which are (Cadastral map and Mineral Tenure). The spatial layers (cadastral_parcel and mineral_parcel layers) can contain dispute data as shown in the previous sections.
Land Use
Land use data can be uploaded in two different spatial data types, vector and raster.
Spatial_plan Layer
In this spatial layer schema, you can add data of an ongoing/ceased spatial planning project whether it was a national development project or private investment.
Land_use_object Layer
Every vector land use feature represents a land use object. A land use object is a homogeneous land use area that can be categorized in one of main 13 categories according to hillucs_land_use codelist as shown in the following ER Diagram.
land_use (raster) Layer
While preparing the land use raster image, the following colors schema has to be followed for the five main categories:
You can prepare the data for contribution in NELGA LDH according to the schemas shown in the previous questions. The data preparation step can be done practically in one of the GIS applications for spatial data processing such as Esri ArcMap or QGIS.
Inorder to contribute spatial data in NELGA LDH, you don’t need to create the schema for the spatial data layers you want to contribute from scratch. All you need to do is to download a template for your spatial data topic and then you can fill the data in your chosen template using your favorite GIS application.
You can do that by going to the Administration panel and then click on spatial data in the side menu.
After clicking on Spatial data from the side menu, a sub menu will drop down. You can choose any of the spatial data topics. Then, a page to contribute spatial data for this topic will open. You can scroll down a little bit on this page until you see the “DOWNLOAD TEMPLATE” button. Please click on it and choose the data type of the template. It can be either shapefile or geopackage.
In this example a land cover geopackage template will be used in QGIS.
The attribute table for this file, shows the attributes that need to be filled with data. You can simply fill this file with spatial data and then upload it in NELGA LDH.