Study On The Comparison And Analysis Of The Broad Leaved-coniferous Mixed Forest Soil Nutrition Migration Of The Different Secondary Succession Stages

This study applied to the method of that using the special series replacing the timing series, based on the soil formation theory, the relationship between the soil nutrition cycle and the forest litter in the secondary succession of the temperate broad leaved-coniferous mixed forest was studied, in order to build up theory foundation for the restoration of the broad leaved-coniferous mixed forest landscape. The study area located in Zhuojia town jilin province, five secondary succession stages, from the weed community to the mix broad leaved forest community, of the temperate broad leaved-coniferous mixed forest was investigated and analysed, the results are as follows: Correlation analysis indicates that the nitrogen content and phosphor content in soil significantly correlated to the organic matter content. Soil organic matter increases with the succession development, which improves soil physical and chemical condition. with the succession developing, vegetation changes from the weed community into the broad leaved mix forest community, the nitrogen content, phosphor content and organic matter increased in the forest litters. Changes of the soil bulk density, soil quality, and water content in the different succession stages was consistent with the changes of the compositions and structures of the forest litter, which was opposite to the features of the parental materials. With successions getting on, the changes of soil physical property facilitate to the depositing and releasing of the soil nutrition. Consequently, soil total nitrogen, active nitrogen, total phosphor, active phosphor and organic matter all show increasing trend. The nutrition migration between the forest litter and soil is regularly,its changes show a linear trend. With the development of succession, organic matter in soil is of cumulative property, which improves the level of soil development. The difference between the succession stages not only represent in the vegetable type and the species, moreover, soil formation and physical and chemical features are all different because of the variability of the migration between the forest litter and soil. Filbert shrub and Mongolian oak forest community are of higher productivity and grow up quickly, but the structure of their mature forest is simple, prevailing species of the ecosystem is the Filbert or Mongolian oak, which ecosystem proved to be ephemeral, meanwhile, the quality of the nutrition provision ability of them is lower, which is on one side relation to the environmental condition and on the other side to its own biological features .as a result, its natural restoration takes more time. Therefore, in order to utilize land resources rationally, parent forest land have to be restored to the temperate broad leaved-coniferous mixed forest, so the harmony relationship between community, forest litter and soil have to be constructed and to facilitate to the restoration of the natural prototype. Moreover, Based on the co-conforming co-boosting relation ship between the vegetable and soil, soil and forest litter in the succession series, the restoration of the native vegetation can not be accomplished in one action, it have to be realized gradually keeping step with the succession series.