Changes in soil nutrients and carbon properties in relation to grassland salinization

Abstract

Soil salinization is one of the most serious problems in arid and semiarid zones. In this study, we estimated the relationship between aboveground plant communities and belowground soil nutrients and soil carbon storage and salinity in grasslands in the middle reaches of Hexi Corridor, China. Four types of salinized grasslands including lightly, moderately, heavily, and severely salinized grasslands were selected. Aboveground biomass, plant species richness and diversity of plant community decreased significantly with salinity increasing. Salinization resulted in significantly increase in soil available phosphorus, and decrease in soil organic carbon, total nitrogen, available nitrogen, total potassium. No significant difference in total phosphorus was observed. Our results indicate that ecosystem functions such as aboveground biomass, vegetation cover, and some nutrients accumulation in soils are disturbed by salinity. However, we still appeal to protect the naturally salinized grasslands for not only their conservation of endemic and rare plants and animals.