Eerstelaag

Eerstelaag is a Dutch term meaning "first layer." In Dutch scientific and technical usage it is a generic label for the layer that occupies the top position in a stratified arrangement, or the layer encountered first in examination, sampling, or manufacture. The precise interpretation depends on the discipline.

In archaeology and geology, een eerstelaag refers to the layer encountered at the surface or the top-most strata in an excavation or core. It is typically the youngest part of the sequence, and its contents help establish recent chronological phases. In stratigraphic records, it may be affected by modern disturbance, bioturbation, or human activity.

In soil science, the term is often used informally to denote the topsoil, the A horizon or the uppermost soil layer that interacts with rainfall, vegetation, and organic matter inputs. Its properties strongly influence water movement, nutrient availability, and rooting.

In materials science and engineering, een eerstelaag refers to the initial coating applied to a substrate, for example primers or adhesion-promoting layers, upon which subsequent layers are built. The quality of this layer affects adhesion, corrosion protection, and the performance of the whole coating system.

The term does not correspond to a single standardized concept but is defined by the context, often accompanied by more specific terminology such as top layer, surface layer, or initial coat. See also laag, stratigrafie, topsoil, coating.