Strategies in growth and reproduction of the native endangered plant species Scripus mariqueter and the driving factors in a coastal salt marsh wetland, eastern China

Scripus mariqueter is a native endangered plant species with both sexual and asexual reproduction in a coastal salt marsh wetland, eastern China. Understanding the patterns of growth and reproduction of S. mariqueter populations in different tidal flats and the main driving factors is necessary and urgent for the effective restoration of this species. The characteristics of growth and reproduction of S. mariqueter populations were investigated in the seaward, middle and landward habitats along the north, east and south directions of the Dongtan salt marsh wetland. Results showed that when individually and comprehensively analyzing the effect of soil physicochemical properties on the differentiation patterns of the growth and reproduction, based on the pairwise index analysis, SEM (structural equation model) and PCA (principal component analysis), soil salinity was the most important driving factor, and comprehensive factor (Y) played a major role than tidal levels and directions. Soil physicochemical factors independently explained 61.63% of the growth-reproduction variation, in which soil salinity explained 13.78% and the comprehensive factor explained 69.20%. Correlation between sexual and asexual reproduction was negative in series habitats in the north direction, and positive in series habitats in the east and south direction, where soil physicochemical properties in the series habitats in the south direction was relatively unfavorable or stressful than those in the east and north direction in term of sexual reproduction. Our results provided a theoretical and practical basis for the sustainable conservation and restoration of S. mariqueter population, which may further help enhance its ecological functions in protecting beaches, reducing waves, facilitating siltation and maintaining biodiversity in the coastal salt marsh wetland, eastern China.