Effect Of The Grassland Enclosure On The Recovery Of Gression Grassland And Field Liquorice Resource In Ningxia

This research was carried out in Ningxia province, and the study objects were regression grassland and liquorice resource. Based on the investigation of plants and natural environment, such as soil conditions, we studied the effect of Enclosure and Complemental sowing on the recovery of regression grassland and field liquorice resource, the effect of reasonable digging and utilization means on the recovery of grassland and liquorice quality were also studied. The main results are as follows:1. The experiment area can be divided into four main types. The two types that mainly build by liquorice are fit to carry out liquorice production.2. Enclosure is very important to the recovery of regression grassland. The mean value of plant cover degree was increased from 53.6% (2002) to 70.2% (2004) by 16.6%. The production of grass was also increased from 142.4 kg/mu (2002) to 217.8 kg/mu (2004) by 52.9%.3. Enclosure is very important to the protection and recovery of liquorice resource. After three years of enclosure, the cover degree, density and stock of liquorice were all increased. To the year of 2004, the cover degree, density and stock were increased by 29%, 100% and 175.1%, respectively.4.The best exploitation mode of wild Liquorice is alternate plant excavating with excavate big plant and leave small plant, which damage grassland area least and alleviate the press on the grassland ecosystem through carriage the soil return instantly after excavating and increase Liquorice commodity rate and commodity yield and Liquorice quality.5. A new model of liquorice production and the recovery of regression grassland was set up.