Wang Meng-Li, Yu Hai-Bo, Gao He-Miao, Yuan Long-Yi, Ren Ai-Tian
College of Horticulture and Gardening, Yangtze University, Jingzhou 434025, Hubei, China.
Ying Yong Sheng Tai Xue Bao. 2024 Apr 18;35(4):1044-1054. doi: 10.13287/j.1001-9332.202404.002.
Aiming to understand the responses of soil seed bank to different water levels, we investigated vegetation and soil seed bank along a water level gradient (frequently flooded area, unflooded area) on the floodplain wetland of Juzhang River. We used the structural equation model to explore the direct and indirect effects of water level on soil seed bank, and used non-metric multidimensional scaling (NMDS) to assess the role of soil seed bank for vegetation regeneration. The results showed that the density of transient and persistent seed banks at unflooded area was 36.9% and 7.8% higher than that of frequently flooded area, respectively. Shannon index and Pielou index of seed bank and vegetation were significantly affected by water level and sampling location. Water level significantly affected the similarity between seed bank and aboveground vegetation, and the similarity of persistent seed bank with aboveground vegetation was significantly higher than that with transient seed bank. Structural equation model showed that water level had a direct effect on seed bank density, and indirect effects on density and richness of seed bank via affecting soil pH and NH-N content. NMDS results showed that there was no significant difference in the composition of the persistent seed bank and vegetation community in autumn under different water levels, but water level significantly changed the community composition of transient seed bank. Transient seed bank was affected by the vegetation and soil property, while persistent seed bank was determined by aboveground vegetation and water level. Although soil seed bank had low regeneration potential for the vegetation communities in floodplain wetlands, soil seed bank could not be neglected during the restoration of propagule diversity after disturbance in wetlands. Persistent seed bank would be an importance source of diversity of propagules for floodplain wetlands restoration following disturbance.
为了解土壤种子库对不同水位的响应，我们在巨漳河漫滩湿地沿水位梯度（常淹区、非淹区）调查了植被和土壤种子库。我们使用结构方程模型探讨水位对土壤种子库的直接和间接影响，并使用非度量多维尺度分析（NMDS）评估土壤种子库对植被更新的作用。结果表明，非淹区临时种子库和持久种子库的密度分别比常淹区高36.9%和7.8%。种子库和植被的香农指数和皮洛指数受水位和采样位置的显著影响。水位显著影响种子库与地上植被的相似性，且持久种子库与地上植被的相似性显著高于与临时种子库的相似性。结构方程模型表明，水位对种子库密度有直接影响，并通过影响土壤pH值和铵态氮含量对种子库的密度和丰富度产生间接影响。NMDS结果表明，不同水位下秋季持久种子库和植被群落的组成没有显著差异，但水位显著改变了临时种子库的群落组成。临时种子库受植被和土壤性质的影响，而持久种子库则由地上植被和水位决定。虽然土壤种子库对漫滩湿地植被群落的更新潜力较低，但在湿地干扰后繁殖体多样性恢复过程中，土壤种子库不容忽视。持久种子库将是干扰后漫滩湿地恢复中繁殖体多样性的重要来源。
