水位变化对沮漳河河漫滩湿地土壤种子库的影响  

Effects of water level on soil seed bank in the floodplain wetland of Juzhang River,China

作　　者：王梦丽 余海波 高禾苗 袁龙义[1] 任爱天 WANG Mengli;YU Haibo;GAO Hemiao;YUAN Longyi;REN Aitian(College of Horticulture and Gardening,Yangtze University,Jingzhou 434025,Hubei,China)

机构地区：[1]长江大学园艺园林学院,湖北荆州434025

出　　处：《应用生态学报》2024年第4期1044-1054,共11页Chinese Journal of Applied Ecology

基　　金：湖北省教育厅中青年人才项目(Q20221312);湖北省自然科学基金青年项目(2023AFB285)资助。

摘　　要：为了解土壤种子库对不同水位变化的响应,以沮漳河河漫滩湿地为研究对象,沿水位梯度(常淹区,未淹区)调查地上植被和土壤种子库,采用结构方程模型,探讨水位变化对种子库的直接和间接影响,采用非度量多维尺度(NMDS)分析研究种子库在植被重建中的潜力。结果表明:未淹区的短暂种子库和持久种子库密度分别比常淹区提高36.9%和7.8%。种子库和地上植被的Shannon指数和Pielou指数受水位和采样地点双因素的显著影响。水位显著影响种子库与地上植被的相似性,持久种子库与地上植被的相似性显著高于短暂种子库。结构方程模型表明,水位变化对种子库密度有直接影响,并通过土壤pH和NH_(4)^(+)-N间接影响种子库密度和丰富度。NMDS结果显示,水位变化对持久种子库和秋季地上植被群落组成没有显著影响,但显著改变了短暂种子库群落组成。短暂种子库主要受地上植被和土壤理化性质的影响,而持久种子库由地上植被和水位共同决定。在河漫滩湿地中,种子库再生潜力较低,但在水位变化过程中,种子库对湿地扰动后繁殖体多样性的恢复作用不容忽视,持久种子库可能是地上物种多样性的重要来源。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_(4)^(+)-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.

关 键 词：河漫滩 土壤种子库 植被组成 水位 湿地 

分 类 号：Q948[生物学—植物学]