Effects of Fire and Fertilization on the Species Diversity and Biomass Accumulation of Subalpine Meadows

Purpose In this experiment, the plant community characteristics of the degraded subalpine meadows were studied in order to learn the effects of burning and fertilization on grassland rehabilitation.

Method Factors like fire and fertilization were introduced in the experiment and split design was applied. Of this design, fire included burning treatment and no-burning treatment. For fertilization (NPK compound fertilizer), 0, 30 and 60 g/m² were set.

Result Fire and fertilization reduced the dominance and important value of Euphorbia jolkinii of subalpine meadow, and changed the number of plant species and dominant species, furthermore, significantly increased the aboveground biomass (P<0.05), however, its changes were related to both experimental factors and economic component. The combination of fire and fertilization significantly increased the aboveground biomass of Gramineae plants (P<0.05) while decreased forbs. In contrast, fertilization significantly increased the aboveground biomass of leguminous plants (P<0.05). It was observed that burning and fertilization had opposite effects on Shannon-Wiener diversity index and richness index. Burning tended to increase plant species diversity. As a result, plant community structure was changed, which led to community dissimilarity. The similarity coefficient between burning and control reduced to less than 50%, which showed that grassland succession were changed.

Conclusion Fire and fertilization changed the plant species and dominant species of subalpine meadows, reduced the important value of the E. jolkinii, and increased the aboveground biomass of the grassland. The plant community species diversity index, grassland community uniformity, species richness and community similarity coefficient were affected to a certain degree.