土壤电超滤-氮、磷、钾中无机和有机组分的分配及相关研究  

DISTRIBUTION OF INORGANIC AND ORGANIC FRACTIONS IN SOIL ELECTRO-ULTRAFILTRATION (EUF)-N, -P, AND -K AND THEIR CORRELATION STUDY

作　　者：李酉开[1] 任桦[1] 易小琳[1] 

机构地区：[1]北京农业大学,北京100094

出　　处：《中国农业科学》1993年第6期59-67,共9页Scientia Agricultura Sinica

摘　　要：旱地土壤电超滤-氮和磷中无机与有机组分的分配和解吸溶解动态有很大的不同。电超滤-全氮中的硝态氮和有机氮大致各占一半;电超滤-全磷的绝大部分是无机磷,有机磷的贡献极小。电超滤-吸光量与电超滤-氮有极高的正相关,可以相互换算。二者与冬小麦吸氮量都呈高度相关,远优于土壤全氮和碱解氮等化学指数。电超滤-磷与小麦吸磷量也有很高的相关性,与Mehlieh3-P相同,稍低于Olsen-p,但差异不显著。华北石灰性土壤电超滤-钾值(O-35min)仅为交换性钾值的57%二者的相关性极高,与小麦吸钾量呈中等高度的正相关。从电超滤-养分的解吸动态可以显示它们对植物供应的速率。The distribution and desorption (dissolution) rate of inorganic and organic fractious in soil EUF-total N (EUF-N_T) are quite different from those in EUF-P_T. In the 51 aerated calcareous field soils tested, inorganic (nitrate) and organic N (N_No_3 and N(?)) fractions about equally distributed in the soil EUF-N_T. On an average, 91% of EUF-N_No_3 was already desorhed (dissolved) at the earlier stage (0-30min, 20℃) of EUF-extraction Organic N formed the bulk (79%) of the N desorbed at the late stage (30-35min,80℃), but it only made up 37% of the whole EUF-N_(org) (0-35min). In con- trast to EUF-N_T,a larger majority (84%) of EUF-P_T Was mineral P (P(?)) and the greater part (60%) of EUF-P_(?) , as well as EUF-P_(org) , was desorbed (dissolved) at the later stage at higher temperature. The whole lot of soil EUF-K existed in inorganic form. For the 51 calcareous soil samples tested, the EUF-K (0-35min) value only amounted to 57% of the soil NH_4OAc-K value. It showed that the EUF-K (30-35min) fraction might still be mainly exchangeahie-K of the soil.The excellent positive correlation between the EUF-N_T value and the EUF-total absorbability (EUF-Q_T) value determined by the previous paper(r=0.994,n=50) allowed for the conversion of these two parameters into each other with the aid of the following conversion factors,1.00 mg/kg soil EUF-N_T≈0.62q/kg soil EUF-Q_T,1.00q/kg soil EUF-Q_T≈1.61mg/kg soil EUF-N_TThe results of correlation studies showed that both soil EUF-N_T and -Q_T of aerated soils were well correlated with the relative N-uptake of winter wheat in pot experiments (r=0.95, r^2=0.90, n=50), far better than those of some chemical testing values, such as the O.M. , Kj-N, and alkaline hydrolyzable N contents in the soils. Good or significant correlation were also found between EUF-P_T/EUF-K values and relative P-/K-uptuke of winter wheat (r=0.797/0.638,n=50), but the correlatious were inferior to those of Olsen-P/exchangeable or slowly available K respectively.

关 键 词：电超滤 氮 磷 钾 相关研究 

分 类 号：S158.3[农业科学—土壤学]