JOURNAL OF NATURAL RESOURCES ›› 2019, Vol. 34 ›› Issue (12): 2601-2614.doi: 10.31497/zrzyxb.20191210

• Special Forum of "Wetland" • Previous Articles     Next Articles

Seed coating methods and availability for applying in the restoration of salt marsh vegetation in coastal wetlands

SUI Hao-chen1(), MA Xu1, YAN Jia-guo1, ZHANG Shu-yan2, GAI Ling-yun2, LIU Ze-zheng1, QIU Dong-dong1, CUI Bao-shan1()   

  1. 1. School of Environment, State Key Laboratory of Water Environment Simulation, Beijing Normal University, Beijing 100875, China
    2. Huanghekou Management Station, Shandong Yellow River Delta National Nature Reserve Administration, Dongying 257500, Shandong, China
  • Received:2019-03-10 Revised:2019-06-17 Online:2019-12-28 Published:2019-12-28

Abstract:

A crucial question in restoration of coastal saltmarsh ecosystem is how to keep sustainable and evenly distributed seed banks, and approaches to enhance the seed settlement and germination. Thus, an urgent need is to develop a method by ameliorating the available conditions for seeds settlement and germination, thereby promoting the effectiveness of coastal vegetation restoration. Here, using an annual saltmarsh vegetation Suaeda salsa as a model species in the Yellow River Delta, we experimentally enveloped a thin layer outside each seed by three kinds of super absorbent materials, thereby testing their difference and providing an optimal selection for the restoration of Suaeda salsa. The materials we selected were polyacrylamide PAM, hydroxyethyl cellulose HEC, and hydroxypropyl methyl cellulose HPMC, which of each harbors the high ability in water absorption. Firstly, we coated the powder of each kind of absorbent material outside the seeds; secondly, we experimentally manipulated a gradient of water salinity to know the coated seed germination vary with the salinity; thirdly, we experimentally released 30 seeds for testing their mean suspension time and 20 seeds for the whole process of settlement; in the end, we investigated the seeds germination with different absorbent materials. Our results showed that, compared to the natural seeds dispersed to the bare ground, seeds that were enveloped by the water retaining materials (i.e. seed product) significantly harbored more water and maintained the water for a longer time. Our findings are that seed product coated by absorbent materials presented shorter suspension time and quick settlement within the sea water; the seed product significantly increased the germination rate and salt tolerance In addition, we observed that PAM, HPMC and HEC differed significantly in making contribution to the seed suspension, settlement, and seed germination, showing that the seed product with PAM is higher than HPMC, HEC and natural seeds, successively. Our study provides an available approach for governing the persistence of the coastal seed banks, with important management implication to use artificial seed products in the restoration of degraded saltmarsh ecosystems.

Key words: saltmarsh, ecological restoration, seed coating, superabsorbent material, Suaeda salsa