宁洱县典型烟田土壤系统分类研究

Soil Taxonomy of Typical Tobacco Fields in Ning'er County

我国土壤系统分类现处于基层单元土族和土系建设迅速发展阶段。宁洱县是云南省普洱市烤烟主要种植区之一。在宁洱县发生分类的水稻土和黄壤烟田上选择5个典型土壤剖面,通过形态观察和分层采样测试,研究了其在系统分类中的归属。结果表明:5个典型剖面分别隶属于人为土、淋溶土、富铁土3个土纲,续分为3个亚纲、3个土类、3个亚类、4个土族和5个土系;就植烟适应性而言,5个土系的总体优势是土壤质地偏黏,有利于保水保肥,但土壤通透性略差,地形均为坡地,旱地烟田易发生水土流失;属于水耕人为土土纲的土系(水田)有机碳和有效磷养分含量较高,属于淋溶土、富铁土纲的土系(旱地)养分含量低,需要注意适当增施肥料和实施秸秆还田。

Soil taxonomy in China is in the stage of soil family and soil series rapid development. Ning＇er County is one of the main tobacco planting areas of Pu＇er City in Yunnan Province. 5 typical profiles of tobacco fields belonging to the genetic paddy soil and yellow soil were selected, and the morphological characteristics of the profiles and soil chemical properties of horizons were analyzed to determine the soil category in soil taxonomy of the tobacco fields in Ning＇er County. Results showed that the 5 typical profiles could be divided into 3 Orders, namely Anthrosols, Argosols and Ferrosols, 3 Suborders, 3 Groups, 3 Subgroups, 4 Families and 5 Series. The texture of plough horizons of the 5 soil profiles is of clayey, which is beneficial to storing nutrients and water, but poor in permeability. The contents of SOC and the available P of soil series of Anthrosols are high, while the nutrient contents in soil series of Argosols and Ferrosols are lower. Thus, fertilization and straw returned to field should be applied to improved soil fertility for the later soil series. All the typical fields located in the slopes, and contour planting should be adopted toprevent soil erosion, particularly for the dryland tobacco fields.