Maximilian Altstadt, Tobias W Donath, Ermek Baibagyshov, Adilet Duulat Uulu, Myrzabek Kylychbekov, Insa Kühling
The Mountains of Central Asia constitute one of the world's most vulnerable yet least protected biodiversity hotspots. While considerable research has addressed grasslands and forests, arable lands in this region-particularly within the Central Tian-Shan mountains of Kyrgyzstan-remain poorly studied despite their high floristic richness and conservation potential. To address this gap, we conducted systematic vegetation surveys across Kyrgyz croplands to establish the first comprehensive baseline inventory of the segetal flora. Our study aimed to characterise cropland flora composition, examine regional variation across different biogeographical contexts, and assess how species distribution ranges and adjacent habitats shape floristic patterns. Plant composition was primarily determined by proximity to mountain slopes and the influence of regional species pools, whereas species richness was more strongly linked to the structure of edges between fields. They consistently supported higher species richness than field centres, reflecting reduced disturbance, spillover from adjacent fields and local ecological factors such as crop diversity and habitat quality. Across study areas, total species richness increased with proximity to slopes due to the influx of taxa from outside arable fields, many of which were subendemic. These slope-adjacent cropland areas, defined as external ecotones, therefore represent critical zones for biodiversity management, particularly in narrow valleys. A combination of various dispersal vectors and disturbance-driven niche creation facilitates the establishment of rare species within farmland. Climate change, interacting with orography and agricultural practices, is expected to intensify these processes, underscoring the role of high-mountain croplands as vital refugia within a trans-landscape conservation framework that integrates natural and agricultural systems.