Upkeep - Reference parcel processing
Updates and refreshes
As a part of upkeep (see the highlighted part of Figure 3.1), update is the process of addressing non-conformities due to the changes on the land. It involves all the operations and database interventions necessary to give a reference parcel up to date attribute values. Any change that cannot be attributed to the life-cycle dynamics of the land but is due to appearance or dissappearance of physical features is called a " manifest change".
The EC services consider four generic cases of manifest changes:
- Type I: irreversible conversion of agricultural land covers. It involves conversion into a land cover unsuitable for agrictultural activaties (“inclusions” that are 1000m2 or more and/or along the perimeter that results in average more than 5 meters wide and measure more than 100m2). Type I also includes the opposite conversions from non-agricultural into agricultural land cover.
- Type II: the appearance of permanent constructions, regardless of their width and size such as building, processing facility, artificial surface pavement, or other man-made structure that remains more than three years onsite, which changes the land cover or soil condition in a way that normal agriculture activities cannot be carried out.
- Type III: change of the perimeter at least between two reference parcels manifesting in splitting, merging, or mutual exchange of land.
- Type IV: change in the perimeter of a single reference parcel that is caused by inclusion of previously unidentified agricultural land to that reference parcel.
Figure 3.2 represent the UML process diagram of update.
- In summary, updates for
- changes of type I follow the detailed processing schema for confirming the change and committing a new reference area when the difference is significant.
- changes of type II require reduction of the reference area to take into account the newly appeared feature.
- changes of type III require the digitization of the new perimeter segments.
- changes of type IV need to be treated as completion of an omission. From that that point on, they are no longer in scope of the update guidance but follow the non-update processing
Area modifications triggered by type I and type III are subject to the threshold set by the expected area error amplitude (EAEA), inherent to the border of the polygon.
In all cases, completely new reference parcel(s) can be created from scratch and act as completely new reference parcel. At that point, they are no longer in scope of the update guidance but follow the non-update processing
Update process and sequence diagram
Figure 3.3 provides a general overview of reference parcel processing (the part bounded by red line):
figure 3.3: Sequence diagram for reference parcel processing
As shown in the red highlighted part of the diagram the update process consists of the following steps:
- dedicated personnel or contractors retrieve an existing anomaly and RP data (5.0), review parcels and deliver data (5.0.2). They may perform some data processing (5.0.1), which is optional, since data processing is mandatory at the level of LPIS custodian only.
- the LPIS custodian operator retrieves existing anomalies and RP data (5.0). The operator describes and assesses the anomalies, carries out data processing and testing (5.1) and then performs the necessary database operations (5.2).
- before committing the change (5.3) to the RDBMS, the LPIS custodian reviews the reference parcel against the existing anomaly and RP data (5.0).
Go back to the main upkeep article