Kasviatlaksen kolmas ulottuvuus

Collection of field data for the Atlas of the vascular flora of Finland started in 1985. The original mapping period was planned to be 1985–1990, but the field work has continued yearly since then. Now, after 37 years of field work, it is important to take into account possible changes in the distribution and abundance of the species during the mapping period. We calculated distribution maps for the species based on the atlas data collected by the end of 1990 and 2020, respectively. For those species showing little change in abundance between the years, the maps are surprisingly similar. The main
difference is greater detail of small-scale variation in 2020 compared with 1990.
For documenting true change in the abundance and distribution of the species,
we have calculated distribution maps separately for the atlas data collected in 1958–1999 and in 2000–2020. These maps will be published online on the Atlas website (kasviatlas.fi) in June 2022. Transforming the function of the Atlas from mapping to monitoring is discussed. The most valuable information might be available by resurveying some of the Atlas squares originally surveyed in 1985–1999. A pilot study is
planned for the summer of 2022.