Research on the Species Diversity and Distribution Patterns of Wild Ribes in Northeast Asia

<i>Ribes</i> is the only genus in the Grossulariaceae family and holds considerable economic importance. Northeast Asia represents one of the major global centers of <i>Ribes</i> distribution. This study presents the first comprehensive investigation focused on this region, examining the diversity, distribution patterns, and environmental determinants of wild <i>Ribes</i> species through field surveys and a review of the relevant literature. Results indicate the presence of 36 species (including 8 varieties) from 7 subgenera of wild <i>Ribes</i> across Northeast Asia, predominantly belonging to the subgenera <i>Berisia</i>, <i>Ribes</i>, and <i>Grossularia</i>. The species are unevenly distributed throughout the region: (1) The Russian Far East exhibits the highest species richness, with 21 species from 5 subgenera, followed by Northeast China (16 species, 6 subgenera), Japan (12 species, 7 subgenera), Mongolia (10 species, 3 subgenera), South Korea (9 species, 5 subgenera), and North Korea (8 species, 5 subgenera). These findings suggest that the Russian Far East currently serves as the core distribution center for <i>Ribes</i> in Northeast Asia. (2) The species diversity of wild <i>Ribes</i> exhibits a unimodal latitudinal pattern, peaking between 47° N and 52° N. (3) A similar unimodal trend is evident along altitudinal gradients, with most species occurring between 500 m and 1500 m. (4) Species richness is primarily influenced by temperature stability and extreme low temperatures, followed by precipitation seasonality and elevation, while annual precipitation shows a relatively minor effect. This study offers crucial baseline data for the conservation and sustainable utilization of <i>Ribes</i> in Northeast Asia.