Vascular plant diversity and distribution pattern in Tajikistan: A global hotspot of diversity

doi:10.1016/j.regsus.2026.100294

Abstract

Abstract:

Tajikistan represents a core region of the biodiversity hotspot in Central Asian mountains and has exceptional vascular plant diversity. However, the species diversity of the country faces urgent conservation challenges. There has been a lack of a comprehensive and multidimensional assessment to inform strategic conservation planning. Therefore, this study integrated 4 key biodiversity indices including species richness (SR), phylogenetic diversity (PD), threatened species richness (TSR), and endemic species richness (ESR) to map species diversity distribution patterns, identify conservation gaps, and elucidate their effects of climatic factors. This study revealed that species diversity shows a clear trend of decreasing from the western region to the eastern region of Tajikistan. The central-western mountains (specifically the Gissar-Darvasian and Zeravshanian regions) emerge as irreplaceable biodiversity hotspots. However, we found a severe spatial mismatch between these priority areas and the existing protected areas (PAs). Protection coverage for all hotspots was alarmingly low, ranging from 31.00% to 38.00%. Consequently, a critical 64.80% of integrated priority areas fall outside of the current PAs, representing a major conservation gap. This study identified precipitation seasonality and isothermality as the principal drivers, collectively explaining over 50.00% of the diversity variation and suggesting high vulnerability to hydrological shifts. Furthermore, we detected significant geographic sampling bias in the public biodiversity databases, with the most critical hotspot being systematically under-sampled. This study provides a robust scientific basis for conservation action, highlighting the urgent need to strategically expand PAs in the under-protected southwestern region and to mitigate critical sampling gaps through targeted data digitization and field surveys. These measures are indispensable for securing Tajikistan’s unique biodiversity and achieving the Kunming-Montreal Global Biodiversity Framework Target 3 (“30×30 Protection”).

Key words: Vascular plant, Species diversity, Distribution pattern, Conservation gaps, Tajikistan

ZHOU Yixin, MA Suliya, LI Wenjun, Parvina KURBONOVA, Mariyo BOBOEV, LI Yufan, Hikmat HISORIEV, MA Keping, YANG Weikang, ZHANG Yuanming. Vascular plant diversity and distribution pattern in Tajikistan: A global hotspot of diversity[J]. Regional Sustainability, 2026, 7(1): 100294.

Figures/Tables 8

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