A Change of Vegetation and Soil of the Desertified Grasslands on the Process of Recovery. 2. At the sites of non-saline meadow and saline meadow.

Following the study in the previous paper^4) of the change of vegetation and soil on the process of recovery of the desertified grasslands at the sand dune (site No. 1) and the fiat sandland (site No. 2) in Keerqin Sandland, Inner Mongolia, China, the same study has been carried out at two sites of non-saline meadow (No. 3) and saline meadow (No. 4). The following results were obtained. The meadow which is harvested plants for hay in autumn and grazed in winter is more conservative land utilization than the pasture which is grazed yearlong. Vegetation and soil of three grasslands (A, B and C) which have different backgrounds of land utilization were compared at site No 3. Plot A has been the pasture land for 30 years, B plot had been the pasture land for 20 years and after then it has been the meadow land for 8 years, C plot has been the meadow land for 30 years. Coverage of vegetation (%) was C plot>B plot>A plot. B plot had a higher coverage of species which indicate non-degradation but had a lower coverage of species which indicate degradation than A plot. Thus, vegetation condition of A, B and C plot were poor, fair and excellent, respectively. The soil organic matter and available nitrogen were C plot )B plot≧A plot. Soil pH was C plot<B plot<A plot, A plot was the most alkalined and C plot was the least alkalined. Thus, B plot kept better condition of soil and vegetation than A plotthough C plot had the best condition. It is considered that on the process of rehabilitation of degraded pasture land vegetation and soil are corresponding each other. On the saline meadow at site No. 4, a gypsum land plaster was applied to improve soil salinity 15 years ago (B plot). Vegetation and soil of B plot were compared with A plot (control). Vegetation of B plot had a higher plant height, coverage and standing crop than A plot. Moreover, it had fewer saline tolerant species. Soil of B plot had a lower pH and salts, and showed the remarkable improvement of the salinity. Besides, it had a higher content of the organic matter, available N and P, and fertile than A plot. Thus vegetation and soil were improved correspondingly by a gypsum land plaster. Considering the results of sites 1-4, the followings are pointed OUt. There is a high correlation coefficient, r= 0.97, between the organic matter and available N. Accumulation of the soil organic matter and the vegetation development are closely correlated. To diagnose the stages of recowery from desertified grasslands, not only the life form and the growth form of dominant species but also measurements of vegetation such as coverage, plant height, the number of annual and perennial species, and existence of degradation indicator speciesl etc. are effective.