Research On Soil Genetic Characteristics And Taxonomic Classification In Niubeiliang National Natural Reserve

Niubeiliang National Nature Reserve has important forest resources in China,it was builtlater and the soil development was young.The forest soil of Niubeiliang National NaruralRewerve has lack of a comprehensive and systematic investigation and study.Took soilsamples of16complete soil profiles in different altitude range in four main Protection ofNiubeiliang National Narural Rewerve research in this study. By field investigation, collectionof typical soil samples, combined with indoor soil physical and chemical analysis and themathematical statistics.Based on comprehensive and systematic study of the physical andchemical properties of the Reserve,to discussed and summarize the development process andevolution rule,diagnostic horizons and diagnostic characteristies were determined. To retrievethe16soil samples under the Keys to Chinese Soil Taxionomy,the taxa includedorder,suborder,group and subgroup, determined the positions in Taxonomy classification andthe distribution of the soil, established the soil vertical zone spectrum and determined theboundaries.This study intends to provide the theoretical foundation for Soil Taxonomy ofmountain and resources development and future management.The results indicate that:1. The main physical and chemical characteristics vary regularly with the rising of thealtitude:the soil color between yellow orange to yellow-brown,and the depth of soil wasshallow.Soil sand proportion of mechanical composition firstly decreased then graduallyincreased along with increased sampling altitude,but soil slit propotion changed in theopposite,soil clay proportion has been at least.The soil mechanical composition differences ofeach layers in common soil profile was larger at low and high altitude areas.2. The spatial distribution range of soil nutrient index in Niubeiliang National NaturalReserve was pH value5.35⁶.65,organic matter5.65⁷4.84g/kg,total N0.30⁵.43g/kg,available N106.64²08.66mg/kg,total P0.45¹.30g/kg,available P0.44⁶.82mg/kg,total K14.88¹8.78g/kg，available K26.18²77.00mg/kgï¼›The spatial variation degree ofsoil organic matter,total N, total P and available P was big, whereas soil pH value and total Kwas smallï¼›the spatial variation degree of soil pH value,total K and available K decreased withthe deep of soil,whereas soil total N and available N increased. Correlation analysis showedthat the. contents of soil organic matter,total N,P, K,available N,P,K,and soil pH value were significantly correlated to altitude.The contents of soil organic matter, available K and soil pHvalue firstly increased to the highest values at altitudes from1900m to2000m,and thengradually reduced along with increased sampling altitude.3. The soil CEC contents was between6.28to26.74cmol/kg,and as the soil depth,thesoil CEC content gradually reduced.The BS basically morn than50%and all belonging to thebase saturation. With the chemical composition analysis,we can find the content ofSiO₂,Al₂O₃and Fe₂O₃is relatively stablilizationï¼›In the soil body, the content of SiO₂ishighest,the total contents of SiO₂,Al₂O₃and Fe₂O₃occupy more than90%of the mineralparts,and the sequence of mineral elements is: SiO₂>Al₂O₃>Fe₂O₃>K2O>MgO>CaO>TiO₂>MnO₂,4. The diagnostic surface horizons divided on the soils of the Reverse are Mollicepipedon and Ochric epipedon.The diagnostic subsurface horizons are Cambic horizon andArgic horizon.The diagnostic characteristics are Folic soil materials,Soil moistureconditions,Soil temperature conditions,Base saturation and Ferric property.According toretrieval, the forest soil of Niubeiliang National Narural Rewerve are divided into twoorders,three suborders,seven groups and nine subgroups in Soil Taxonomyï¼›the verticalstructure in Niubeiliang National NaruralReserve:Tipic-Hapli-Udic Argosolsâ†'Tipic-Hapli-Udic Cambosolsâ†'Typic-Ferric-Udic Argosolsâ†'Tipic-Acidi-Udic Cambosolsâ†'Tipic-Hapli-Udic Cambosolsâ†'Molli-Hapli-Udic Cambosolsâ†'Typic-Ferric-Udic Cambosolsâ†'Tipic-Hapli-Bori Argosolsâ†'Molli-Bori-Udic Cambosolsâ†'Tipic-Hapli-Bori Argosolsâ†'Tipic-Bori-Udie Cambosols。5.The results of Soil Taxonomy consist fundamentally with that of the geneticclassification and the boundaries roughly identify with each other,indicating the taxonomicclassification is based on the genesis theory and the two classification system are touchedtightly.