Abstract
Segetal flora of cereal crop agrocenoses in the Suwałki Landscape Park was studied in between the years 2012 and 2013. One hundred phytosociological Braun-Blanquet releves were taken, documenting the occurrence of 152 species of vascular plants that represented 29 botanic families. Analysis of the contributions of geographic-historical groups revealed the dominance of the native species, apophytes (87 species, making 57.2%), over anthropophytes (65 species, 42.8%). The number of short-lived species was twice greater (103 species, 67.8%) than the perennial ones (49 species, 32.2%). As regards the lifeforms, the therophytes were dominant (96 species, 63.2%) over hemicryptophytes (44 species, 28.9%) and geophytes (12 species, 7.9%). Among the species of segetal flora in the area studied, 23 valuable species classified to different categories of protection, were identified. The presence of Consolida regalis, Centaurea cyanus and Bromus secalinus, belonging to threatened species in other regions of Poland, was abundant. Also the species: Anthemis tinctoria, Echium vulgare and Anchusa officinalis were met with high frequency. The species: Agrostemma githago, Papaver argemone and Papaver dubium were represented by single plants, which can suggest their dying out. In the Park area, expansive species, threatening the biodiversity, such as Myosotis arvensis, Viola arvensis, Galeopsis tetraehit, Stellaria media, Artemisia vulgaris, Galinsoga parviflora, Elymus repens, Capsella bursa pastoris, Erodium cicutarium, Chamomilla recutita, Matricaria maritima subsp. inodora, Convolvulus arvensis, Polygonum persicaria, Polygonum lapathifolium subsp. pallidum and Polygonum lapathifolium subsp. lapathifolium, were commonly seen in the crop land.