论文部分内容阅读
通过比较不同土地利用方式下赤红壤pH值、粘粒、容重、孔隙度、有机碳、氮磷钾全量及其速效养分含量的差异,并运用主成分分析方法分析各变量的相互关系、土壤综合理化特征及其关键改良因子。研究结果表明:新垦旱地容重最高,粘粒含量和孔隙度最低;有机碳、全量氮磷钾养分和速效氮磷养分含量均处于较低水平(P<0.05)。果园土容重显著低于其他土地利用方式土壤,且全氮、碱解氮和速效磷钾水平均处于较高水平(P<0.05)。桉树林的全钾和速效钾含量显著高于灌木林,而粘粒含量和速效磷含量相对较低(P<0.05)。主成分分析结果显示:新垦旱地、果园和桉树林、灌木林土壤理化综合质量差异显著(P<0.05),其中新垦旱地当前质量相对较差。有机碳、全氮和速效氮养分缺乏是当前新垦旱地土壤理化质量较差的主要原因。较少的速效磷钾养分含量是当前桉树林地、灌木林土壤质量的限制因素。主成分分析不仅能够区分不同土地利用方式下赤红壤理化质量差异,而且也是探查改良土壤质量因子的有效方法。
By comparing the differences of pH value, clay, bulk density, porosity, organic carbon, total N, P and K contents and their available nutrient contents in latosolic soils under different land use patterns, and using principal component analysis to analyze the relationship among variables, Physical and chemical characteristics and their key improvement factors. The results showed that the fresh weight of dry land was the highest, and the clay content and porosity were the lowest. The contents of organic carbon, total nitrogen, phosphorus and potassium and available nitrogen and phosphorus were both lower (P <0.05). The content of soil orchard in the orchard was significantly lower than that of other land use types, and the total N, available N and available P and K levels were all at a high level (P <0.05). The total potassium and available potassium in Eucalyptus forest were significantly higher than those in shrub forest, but the clay content and available phosphorus content were relatively low (P <0.05). The results of principal component analysis showed that there was significant difference (P <0.05) in the comprehensive quality of soil physical and chemical properties between newly reclaimed dry land, orchard and eucalyptus forest and shrubbery, and the current quality of newly reclaimed dry land was relatively poor. Organic carbon, total nitrogen and available nitrogen deficiency is the main reason for the poor physical and chemical quality of newly reclaimed dry land. The less available phosphorus and potassium nutrient content is the limiting factor of soil quality of eucalyptus woodland and shrubbery. The principal component analysis not only can distinguish the physical and chemical quality difference of the red soil under different land use patterns, but also is an effective method to explore and improve the soil quality factor.