摘要
本文研究了我国北方农区主要土壤的固钾能力。结果表明,在施K量0-4000mg/kg范围内,土壤固钾量与施钾量的关系符合方程y=ax^(3/2)/(x^(3/2)+b)。不同土壤固钾量相差很大,其固钾量与土壤矿物学性质和理化性质(粘粒含量、CEC、非交换性钾和速效钾含量)有关,与原始土壤非交换性钾含量呈显著负相关(不同施钾水平下土壤固钾量与非交换性钾含量之间的相关系数均在-0.6769以上)。供试土壤固钾能力表现出一定的地带性分布规律。施K1200mg/kg以下时土壤固钾能力的一般趋势是取自西北的土壤<取自东北的土壤<取自华北的土壤;而施K1200mg/kg以上时土壤固钾能力,从西向东呈逐渐增加的趋势。取自西北地区的土壤,固钾量(施K量为400～4000mg/kg,下同)平均为133～348mg/kg,最大同钾量平均是372mg/kg;取自华北地区的土壤,其固钾量平均为235～1001mg/kg,最大固钾量平均是1121mg/kg;取自东北地区的土壤,其固钾量平均为199～1254mg/kg,最大固钾量平均是1519mg/kg。
Potassium fixation by soils was studied for 25 soil samples taken from major agricultural regions of north China with 0~4000 mg K added to each kilogram of soil. Potassium fixation can be well discribed by an equation y=ax3/2 /(x3/2+b) (y is the amount of K fixed in mg/kg, x is the amount of K added in mg/kg, a is an estimation of maximum potassium fixation in mg/kg, b is a constant ). Fixation power of the various soils differred significantly, the amount of K fixed was closely related to the types and the amount of clay minerals existing in the soil, and physical and chemical properties (clay content, CEC, non-exchangeable K and available K levels). Potassium fixation by soils was negatively correlated with non-exchangeable K content of the soils. Soils taken from different regions showed different K fixation characteristics. When K application level was below 1200mg/kg soil, capacity of K fixation of these tested soils followed a general order: soils from northwestern region < soils from northeastern region < soils from northcentral region;while K added was above 1200mg/kg, K fixation power of the soils showed a general tendency: soils taken from northwestern region < soils from northcentral region < northeastern region. When 400~4000 mg K was added to one kilogram of soil, on average, 133 ~ 348 mg / kg were fixed by soils from northwestern region with an average maximum fixation of 372 mg/kg; 235~1001mg/kg were fixed by soils from northcentral region with an average maximum fixation of 1121 mg/kg; 199-1254 mg/kg were fixed by soils from northeastern region with an average maximum fixation of 1519 mg/kg soil.
出处
《植物营养与肥料学报》
CAS
CSCD
1996年第2期131-138,共8页
Journal of Plant Nutrition and Fertilizers
基金
国家自然科学基金
关键词
土壤
外源钾
最大固钾量
固钾率
拟合方程
Soil K applied Maximum amount of potassium fixation Percentage of potassium fixed K fixation equation
