[GIS] Cut part of a shapefile

multipartqgisqgis-2

This is my first time with QGIS and maybe it is an easy question but I can't figure out how to cut part of a layer to add it to another one.

In the image you can find (red circles) parts of a layer totally embedded in other layers. I would like to "cut" that parts and join/add to the surrounding layer.
enter image description here

I have tried to freehand selection tool but after defining the selected area the whole layer is selected. I just want to select the embedded piece, then create a new layer and add to the surrounding one.

Shapefiles have only one attribute, so I can't (do not want) to select by attribute but for region.

Shapefiles available in this file (Dropbox link)

I'm using QGIS 2.18.3 under Ubuntu 16.04.

As a novice any idea or advice is welcome

Best Answer

The reason why you cannot choose the embedded piece alone is that your layer has multipart polygons. Try Vector | Geometry Tools | Multipart to singleparts to break them apart.

Or you may want to try an excellent plugin Multipart Split. It enables us to split only aimed poygon and the splitted polygons are written directly onto the same layer, so your task can be done quickly and efficiently.

Related Question