贵州喀斯特区C4植物物种组成与水分生态型划分

该研究通过查阅文献、核对贵州大学林学院标本库及现场群落调查与标本采集,并运用碳同位素比值法研究典型C_4植物水分利用特性,探索C_4植物在喀斯特植被恢复中的地位,进而揭示贵州喀斯特地区C_4植物资源的基本特征。结果表明:贵州喀斯特区共有C_4植物141种,隶属于74属15科,分别占全国科属种的62.50%、46.25%、24.48%,以禾本科(Gramineae)和莎草科(Cyperaceae)为主;区内C_4植物种均为一年生或多年生草本,多年生植物种略多于一年生植物种;水分生态型整体偏旱生,旱生和中生植物分别占总数的24.82%和31.21%;喀斯特区C_4植物具有高水分利用效率,但不同水分生态型间差异不显著;贵州喀斯特区C_4植物资源具有资源丰富、利用途径广泛、能长期利用、竞争力强、能大面积分布、偏旱生且水分利用幅度广的基本特征,适合喀斯特区生境,自然状态下多为恢复早期物种,有利于喀斯特区生态恢复。在贵州喀斯特恶劣生态环境下C_4植物有较好的生态适应性,并表现出较高的药用、食用、饲用、景观应用等价值,对其开发利用对贵州经济、社会发展及生态恢复有重要意义。

Species composition and water ecotype division of C4 plant in Guizhou karst region

The status of C₄ plants in vegetation restoration of the karst region was explored, and the essential characteristics of C₄ plant resources in Guizhou karst region were revealed, by consulting literatures, checking the specimen library of Forestry College of Guizhou University, investigating on-site community and collecting specimens, as well as based on carbon isotope ratio method to study the water utilization characteristics of typical C₄ plants. The results showed that 141 species of C₄ plants belonging to 74 genera and 15 families were found in the Guizhou karst region, which accounted for 62.05%, 46.25% and 24.48% of the countrywide families, genera and species respectively, and they were composed mainly of Gramineae and Cyperaceae; The species of C₄ plants in the area were either annual plants or perennial plants, and the species number of perennial plant were slightly more than the annual plant; The overall water ecotype was dry, and the siccocolous and the mesad accounted for 84.82% and 31.21% of the total amount; C₄ plants in karst region had high water use efficiency, while there was no significant difference among different water ecotypes; The C₄ plant resources in Guizhou karst region had the essential characteristics of abundant resources, wide application, long-term utilization, strong competitiveness, large-area distribution, drought-producing and wide water use. Karst region provides a suitable habitat for C₄plants. Under natural conditions, most of them are restoring early species, which is conducive to ecological restoration in karst region. C₄ plants have good ecological adaptability under the harsh ecological environment of Guizhou karst region, and present relatively high value for medicinal, edible, feeding, landscape and other purposes. The exploitation of C₄ plants is of great significance for the ecological restoration in Guizhou and the economic and social development of Guizhou area.