Ecological Benefits Of The Different Measures On Serious Erosion Area

In south of China, red soil developed from granite undergo severely erosion. Although for a long time, people have done lots of ecological restoration in this area, but few researches have done on synthesized ecological benefit. It makes lack of theory basis for promoting effective restoration measures. Our research was carried out in the serious eroded area, located in Changting County, Fujian Province. There are three kinds of management measures: old-man Masson pine rehabilitation (OMPR), repair planted trees and shrubs (RPTS), grass mixed with shrub and trees (GMST). And we also take severely soil erosion land as check measure (CK). In this study, we discussed the ecological benefits from soil property, vegetation, runoff sediment, and microclimate. Our results showed that:(1) The soil porosity, soil aggregate, antierodibility, and soil infiltration rate were improved by those measures. The drainage and ventilation of soil also increased, and the soil dispersion rate decreased. The soil physical improvement of those measures was sequence of GMST>OMPR>RPTS.(2) Soil organic matter, total N, total P, total K, available N, available P, and available K of those measures were higher than check measure. This means ecological restoration measures can improved soil fertility, and the sequence of measures'effect was GMST> OMPR> RPTS> CK.(3) Compared with CK, the soil microbial biomass (SMB) were increased obviously (about 53.4% to 98.4%) in those measures. The sequence of SMB was GMST> OMPR> RPTS> CK. The microflora varies form measure to measure. The proportion of bacteria in different measures varies form 43.0% to 47.6%, epiphyte varies form 30.6% to 35.2%, and ray fungi vary form 21.0% to 23.7%. Compared with the natural forest, the proportion of bacteria in those three measures was lower than natural forest. But the proportions of epiphyte and ray fungi were higher than natural forest.(4) The analysis of vegetation restoration and growth showed that: by contrast, the forest cover rate increased form 21%~23% to 83%~92% in different treatments, and the annual timber growing stock also increased from 1.06 m~3/hm~2 to 3.4~5.1m~3/hm~2. Stands and grass cover grew faster, and the plants in the management areas appear the obvious increase trend. Compared with CK (11species, 11 genera, 10 families), the plants in the plot of GMST enjoy the most abundant species, reaching 31 species of 28 genera under 18 families. There are 25 species, 22 genera, and 17 families in RPTS and the OMPR have 16species, 14 genera, and 12 families. So the species richness can be ranked as: GMST> RPTS> OMPR> CK.(5) The amount of soil erosion in those three measures is lower than 500 t/km~2/a year, the grades of soil erosion intensity reaching non-erosion. Compared with CK, the amplitude reduction for soil erosion module in management plots reached 91.6%~95.1%, and the runoff coefficient also reduce 38.0~45.9%. The soil and water conservation benefit was in sequence of GMST> RPTS> OMPR> CK.(6) The soil management measures, by contrast, can reduce soil temperature, reduce temperature's daily variation, and increase moisture. But different measures have various effect on microclimate, the tendency of different treatments on microclimate was GMST> RPTS> OMPR> CK. This may be cause by the different vegetation types and the forest cover rate.As we have seen, different measures can improve soil quality, promote vegetation growth, increase biodiversity, reduce runoff and soil erosion, and change microclimate. And the GMST treatment has obvious ecological benefit in three measures. It shows that in serious erosion area, if we take appropriate biological measures (such as GMST plus level trench), we can increase forest cover rate effectively, control soil erosion, prevent soil degradation. And also we can improve soil fertility, increase soil antierodibility. Only in this way, we can effective improve erosion areas'environment.