| The distribution of Latosolic red soil area is the widest in southeast coast in Fujian. It is up to (61.544 ) hectares, and accounts for 5.09% of the whole provincial area. Also, there is serious soil and water loss and degradation of ecosystems due to common high rainfall nature of the climate and fragile soils on steep slopes. Through artificial measure - Ecological orchard that with straw covering and soil dressing in the orchard is a kind of typical orchard ecosystem in the south of Fujian Province, and the ecology restoration measure of planting Pinus Elliottii is a kind of typical artificial forest ecosystem.In this study, soil physical properties, nutrient content and different soili organic C fractions were measured in orchard, Pinus Elliottii plantation, native mixed secondary forest and the bare land (control). This information is also important for further understanding of change in soil process and predicting consequences of soil fertility when ecology restoration measure has been done. The results showed that:(1) When different measure had been done in orchards, soil physicalproperties were improved. Water holding capacity was the highest intreatment I, but was only 5.6% higher than that in control I. This indicatedthat the restoration of water holding capacity of Latosolic red soil was slow.(2) In the straw covering orchard, amount of soil microorganism, contents ofsoil organic C and nutrient (including available N, P and K) all increased. This effect was also found in orchard where dressing soil measure had been done, and Pinus Elliottii plantation. While the soil fertility responses in the latter were not obvious.(3) The sequence of contents of soil total N, P and K was control II > treatment I > treatment II > treatment III ~> treatment IV> control I. Soil hydrolysable N content in different treatments was more than 40 mg-kg"1 except for control I. Also, various treatments had relatively higher available K content except for control and treatment III. The ranges of soil total P and available P contents in different ecosystems was 0.07-0.544 g-kg"1 and 0.072-18.40m g-kg'1 respectively. Significant difference in contents of total and available P among different treatments was found.5) Total N, total P, total K, hydrolysable N, available P, available K and soil organic matter at top 10cm soils serves as important indicators for soil fertility. The order of soil fertility in different treatments using grey relation analysis based on indicator mentioned above was treatment I (0.825)> treatment V ( 0.803)> treatment II (0.734)> treatment IV (0.529)> treatment III (0.495)> contrast I (0.333). The corresponding order for soil fertility using indicators of soil organic C, light fraction organic C, microbial biomass C and dissolved organic C at topsoil was treatment V (0.996 )> treatment I (0.797)> treatment III (0.522)> treatment IV (0.52) > treatment II (0.519)> control (0.333).In conclusion ,soil fertility has been greatly improved through different controlled measurement, and this effect was most obvious in measure of straw covering. Thus appropriate measurement should been made in orchard to prevent soil degradation.
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