摘要
本区施用锌肥的有效土壤条件主要决定于土壤有效锌(DTPA—Zn)含量,一般以土壤有效锌含量低于0.5ppm作为土壤缺锌临界值,本区缺锌土壤占测定总数的62.5%。锌肥肥效还与土壤氮、磷供应水平密切相关。本区土壤中锌的形态,按含量顺序依次为:Res-Zn>CFeOX-Zn>AFeOX-Zn>Cab-Zn>OM—Zn和MnOX—Zn>Ex—Zn,采用逐步回归方程运算表明:MnOX—Zn和CFeOX—Zn与土壤有效锌含量密切相关,并与作物植株含锌浓量、吸锌量呈显著正相关。本区城市附近污灌农田土壤均受锌污染,锌污染深度为33cm,在下有滞水层时可达66cm,当土壤含锌量超过一定量时,作物生长受阻,并出现毒害症状。
The application of zinc fertilizer and soil zinc fractionate statue in lossial plateau region were studied, The main sesults showed that:
1. There are no doubt that zinc fertilizer has an effect closely corrected with the content of DTPA-Zn in soil, and it has been bound up with the content of N and P. More than 60% soils are Zn-deficient in this area.
2. The Zn-forms in loessia plateau soils may be fractionated chemically into: 1) water and exchangeable Zn ( Ex-Zn) , 2) carbonate bourided Zn (Cab-Zn), 3) organic bounded (Om-Zn), 4) bounded by Mn-oxide ( MnOx-Zn), bounde by amorphous Feoxide ( AFOx-Zn), occupied in crystalline Fe-oxide (CFeOx-Zn) and residual mainly in the mineral stracture forms (Res-Zn).The order of amount present in soils is: Res-Zn CFeOx-Zn AFeOx-Zn Cab-Zn MnOx-Zn Om-Zn Ex-Zn. The soil DTPA extractable-Zn was mainly dependent on AFeOx-Zn and MnOx-Zn fractions.
3. The paper mentioned that Zinc pollution have been found near the industrial cities, and has a potential hazard in this region.
出处
《华中农业大学学报》
CAS
CSCD
北大核心
1989年第S1期52-57,共6页
Journal of Huazhong Agricultural University
