Temperate Coastal Salt Marsh Soils—Effects of Grazing and Management Alternatives

Abstract

Salt marshes are important ecosystems that provide a wide range of ecosystem services. Temperate coastal salt marshes at Samborombón Bay have been subjected to increasing grazing intensity. Continuous grazing on this salt marsh during the cold-humid seasons (autumn, winter, and early spring) generated negative changes in soil and vegetation properties. At medium and low elevation level of the salt marsh, grazing increased soil salinity, associated with a higher proportion of bare soil and groundwater proximity (i.e., upward flow of salts from saline groundwater). At the high elevation level, grazing increased the proportion of creeping species, avoiding the presence of bare soil and soil salinization. Grazing changed vegetation composition and decreased forage quality due to a decrease of forage legumes (Melilotus officinalis) and an increase in non-palatable dicotyledonous forbes (Sarcocornia perennis). This chapter proposes a new management alternative to improve forage quality and soil properties of the grassland. It consists in late summer patch burns followed by cattle exclusion during autumn and rotational stocking from winter to late summer. This grazing alternative could promote sustainable use of this salt marsh favoring both, its conservation and productive use.