Effect of Fertilizer Additions on Plant Communities and Soil Properties in a Temperate Grassland Steppe

Temperate grassland steppe is an important natural ecosystem in the world, which is being degraded under the combined pressure of climate change and human over-utilization. Our objective was to determine the effect of inorganic and organic fertilizer addition and determine the appropriate fertilizer resource and additional rate for temperate grassland restoration. The treatments consisted of an inorganic and organic fertilizer, each with three additional rates. The effect of fertilizer addition on aboveground biomass, community structure, soil properties, and N balance were examined using a 2-year in situ controlled trial at Guyuan Grassland Station, Hebei Province, China. The results showed that inorganic fertilizer treatments increased the aboveground biomass, and decreased diversity and evenness of the plant community. Organic fertilizer treatments increased soil total carbon and the carbon-to-nitrogen ratio, but did not significantly change the aboveground biomass and soil available nutrition during the 2-year experiment. The N quantity of plant harvest output is approximate to that of fertilizer addition input in inorganic fertilizer treatment with 75 kg hm(-2) urea and 45 kg hm(-2) diammonium phosphate. The study demonstrated that using fertilizer addition to restore temperature grassland steppe requires a comprehensive evaluation of the diverse services functions of the present and future.