Salt marsh vegetation distribution patterns along groundwater table and salinity gradients in yellow river estuary under the influence of land reclamation

Abstract Estuary protection is a fundamental part of watershed management. However, land reclamation activities affect species distribution patterns and cause ecological degradation. To improve watershed management, we studied the distribution patterns of three typical salt marsh species and their interspecific interactions along groundwater table depth and salinity gradients using an index of Field Box Dimension and a Relative Interaction Index. We also simulated the groundwater gradient after two typical land reclamation activities, sea reclamation and embanking, after ten years. Our results showed that sea reclamation will change the location of the groundwater salinity peak along a land-to-sea transect and that there is no salinity peak after embanking. Vegetation distribution patterns also differed, from a zonal pattern (in salt marsh) to a mosaic pattern (after embanking). The decrease in the salinity gradient of the non-core area is an important cause for the differences we found in vegetation patterns.

[1]  F. Pugnaire,et al.  MEASURING PLANT INTERACTIONS: A NEW COMPARATIVE INDEX , 2004 .

[2]  Sonia Silvestri,et al.  Tidal regime, salinity and salt marsh plant zonation , 2005 .

[3]  B. Cui,et al.  Physical Stress, Not Biotic Interactions, Preclude an Invasive Grass from Establishing in Forb-Dominated Salt Marshes , 2012, PloS one.

[4]  Simulating Dynamic Vegetation Changes in a Tidal Restriction Area with Relative Stress Tolerance Curves , 2016, Wetlands.

[5]  W. Moore,et al.  Groundwater controls ecological zonation of salt marsh macrophytes. , 2015, Ecology.

[6]  J. Jiao,et al.  Impact of Coastal Land Reclamation on Ground Water Level and the Sea Water Interface , 2007, Ground water.

[7]  Zhiyao Song,et al.  Soil saturation index of salt marshes subjected to spring‐neap tides: a new variable for describing marsh soil aeration condition , 2010 .

[8]  B. Cui,et al.  [Niches of plant species in wetlands of the Yellow River Delta under gradients of water table depth and soil salinity]. , 2008, Ying yong sheng tai xue bao = The journal of applied ecology.

[9]  Zhifeng Yang,et al.  What confines an annual plant to two separate zones along coastal topographic gradients? , 2009, Hydrobiologia.

[10]  M. Antonellini,et al.  Impact of groundwater salinity on vegetation species richness in the coastal pine forests and wetlands of Ravenna, Italy , 2010 .

[11]  J. Horton,et al.  Water table decline alters growth and survival of Salix gooddingii and Tamarix chinensis seedlings , 2001 .

[12]  Mark D. Bertness,et al.  PHYSICAL AND BIOTIC DRIVERS OF PLANT DISTRIBUTION ACROSS ESTUARINE SALINITY GRADIENTS , 2004 .

[13]  E. Sudicky,et al.  Salt marsh ecohydrological zonation due to heterogeneous vegetation–groundwater–surface water interactions , 2011 .

[14]  T. Cui,et al.  New discharge regime of the Huanghe (Yellow River): Causes and implications , 2013 .

[15]  Marco Marani,et al.  Vegetation engineers marsh morphology through multiple competing stable states , 2013, Proceedings of the National Academy of Sciences.

[16]  H. Michael,et al.  Saltwater‐freshwater mixing dynamics in a sandy beach aquifer over tidal, spring‐neap, and seasonal cycles , 2014 .

[17]  M. Bertness,et al.  Physical Stress and Positive Associations Among Marsh Plants , 1994, The American Naturalist.

[18]  Hailong Li,et al.  Analytical Studies on the Impact of Land Reclamation on Ground Water Flow , 2001, Ground water.

[19]  C. Crain Interactions between marsh plant species vary in direction and strength depending on environmental and consumer context , 2007 .

[20]  J. Jiao,et al.  Modeling the influences of land reclamation on groundwater systems: A case study in Shekou peninsula, Shenzhen, China , 2010 .

[21]  Mark D. Bertness,et al.  Plant zonation in low‐latitude salt marshes: disentangling the roles of flooding, salinity and competition , 2005 .