Native plant lists had lower total spatial differences but uncertain replacement change in six bison-grazed Konza watersheds, 1996–2000 to 2021–2025

We tested spatial differences in native plant lists at six bison-grazed Konza Prairie watersheds. We used 119 fixed upland plots and open PVC02 version 25 data. We compared 1996–2000 with 2021–2025. A code entered a period list when it occurred in at least three years. Mean richness rose from 26.56 to 40.51 codes per plot. Mean total Sorensen dissimilarity fell from 0.3675 to 0.3455. All six watersheds had lower total differences. The primary Simpson replacement measure changed by -0.0163. Its reference 95% Student t interval across six watershed changes was -0.0353 to +0.0026. Thus, its mean change was uncertain. Requiring all five years gave a larger replacement decrease with an interval below zero. Other list rules gave intervals across zero. All 35 planned period choices had negative observed mean changes, but those comparisons overlap. Prior work already found that grazing can reduce spatial heterogeneity at Konza. This study adds a fixed-pair comparison through 2025 with total and replacement components. Shared grazing, changed field staff and taxon labels limit interpretation. The results describe recorded lists and do not identify a bison effect. The package has raw source files, rights, hashes, code, figures, all results and independent arithmetic checks.

plant diversity · spatial turnover · Konza Prairie · bison · species richness · beta diversity · recorded incidence · reproducible analysis