Effect Of Different Improvement Measures On Characteristics Of Communities And Soil Of Degradated Grassland

In order to explore the restoration effect of various improvement measures on typical savanes degradated L. chinensis grassland, we conducted a study including six treatments (shallow plowing, root cutting, root cutting+fertilizing, root cutting +irrigation, root cutting+fertilizing+irrigation and CK) in Inner Mongolia University grassland ecology research base of MAO deng pasture of Inner Mongolia Xilinhot city from 2012 to 2015, the study used randomized block experiment and set four repeat. In each treatment, we measured the community characteristics, biomass, species diversity indexes and physical and chemical properties of soil in the peak growing season (mid August). Now the main conclusions are following:1 Each treatment can different degree increase aboveground and underground biomass of grassland community, aboveground biomass of L. chinensis, and control miscellaneous grass invasion, reduce species richness, diversity and evenness index of the grassland with a positive effect on the productivity and community structure of degraded grassland except root cutting.2 Fertilizer, irrigation treatment significantly changed the ground-underground biomass allocation of the root cutting grassland, the R/S increased by 6.85%～23.83%, and size of each treatment in the order root cutting+fertilizing> root cutting +fertilizing+irrigation> root cutting+fertilizing.3 The proportion of the main population biomass of the processing occured a significant change:L. chinensis increasing year by year, Stipa krylovii and Cleistogenes squarrosa whole descending, a biennial miscellaneous grass is more only shallow plowing early, the later gradually disappear.4 The surface water content of soil of the processing is lower than CK except irrigation average increased by 10.58%; the early treatment can effectively reduce the bulk density of soil, and as the age growth, the organic carbon content of soil of each sample increase year by year.5 The fire of green phase will make each processing sample to a sharp drop in output, but effect of root fertilizer+irrigation treatment of 266.16g/m2 still is best; the proportion of gramineae plant decreases after burning, leguminosae, chenopodiaceae, compositae and other relatively increase; the fire of green phase can inhibit the growth of the roots grass and bunch grass and add the proportion of a biennial miscellaneous grass and other plants. In addition, fire can increase the surface bulk density of soil and reduce the surface organic carbon content of soil, but no significant difference (P> 0.05).6 After different measures to deal with four years, comprehensive recovery effects of degraded grassland community structure is in proper order shallow plowing > root cutting+fertilizing+irrigation> root cutting+irrigation> root cutting +fertilizing> root cutting.