作 者：
申艳;段英华;黄绍敏;郭斗斗;张盛楠;徐明岗
单 位：
中国农业科学院农业资源与农业区划研究所/耕地培育技术国家工程实验室;河南省农业科学院植物营养与资源环境研究所;河北农业大学资源与环境科学学院
关键词：
施磷;Olsen-P;CaCl_2-P;淋失风险;潮土
摘 要：
【目的】土壤有效磷(Olsen-P)与可溶性磷(Ca Cl_2-P)含量之间存在着平衡,研究磷肥施用量对潮土Ca Cl_2-P和Olsen-P及其比值的影响,评价磷素的淋失风险,可为潮土区合理利用养分资源、减少磷肥投入和流失提供理论依据。【方法】选择长期定位监测基地的5个处理(对照、NPK、预备处理、NPKM和1.5NPKM处理,简称OP1、OP2、OP3、OP4、OP5),5个处理的土壤Olsen-P含量存在显著差异(0.8、12.5、25.7、44.7、56.4mg/kg),据此在每个处理上再设置5个施磷量水平(F0、F1、F2、F3、F4),试验采取微区形式,随机区组设计,种植作物为夏玉米–冬小麦双季轮作。作物收获后,采集土壤样品,测定土壤Olsen-P和CaCl_2-P含量,建立Olsen-P和CaCl_2-P之间的定量关系。【结果】土壤CaCl_2-P含量为0.07～2.68 mg/kg,约为Olsen-P含量的0.5%～5.6%。短期高量磷肥施用可以显著提高土壤Olsen-P和CaCl_2-P含量,但土壤Olsen-P和CaCl_2-P的增加不同步。当土壤Olsen-P低于28.0 mg/kg时,Ca Cl2-P/Olsen-P比值随着Olsen-P的增加而降低,当Olsen-P增加至28.0 mg/kg后,Ca Cl2-P/Olsen-P比值随着Olsen-P的增加迅速增加,这表明磷肥施用首先提高土壤Olsen-P含量,Olsen-P增长到一定程度后CaCl_2-P才迅速增加。土壤CaCl_2-P和Olsen-P的关系符合双直线模型,突变点时土壤Olsen-P含量为30.2 mg/kg,对应的CaCl_2-P含量为0.3 mg/kg。当土壤Olsen-P含量超过30.2 mg/kg时,土壤磷素淋失风险增加。【结论】高量磷肥施用可以提高土壤CaCl_2-P含量,促进作物对磷的吸收,但同时增加了土壤磷素的淋失风险。研究区土壤磷素淋失临界值为30.2 mg/kg,微区试验中超过50%的小区土壤Olsen-P含量已经超过磷素淋失临界值,存在磷素淋失风险,应加强农田磷肥的科学施用和管理。
译 名：
Response of CaCl_2-P to phosphorus fertilization and leaching risk in fluvo-aquic soils
作 者：
SHEN Yan;DUAN Ying-hua;HUANG Shao-min;GUO Dou-dou;ZHANG Sheng-nan;XU Ming-gang;Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences/National Engineering Laboratory for Improving Quality of Arable Land;Institute of Plant Nutrient and Environment Resources,Henan Academy of Agricultural Sciences;College of Resources and Environment Science, Hebei Agricultural University;
单 位：
SHEN Yan%DUAN Ying-hua%HUANG Shao-min%GUO Dou-dou%ZHANG Sheng-nan%XU Ming-gang%Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences/National Engineering Laboratory for Improving Quality of Arable Land%Institute of Plant Nutrient and Environment Resources,Henan Academy of Agricultural Sciences%College of Resources and Environment Science, Hebei Agricultural University
关键词：
phosphorus fertilization;;Olsen-P;;CaCl_2-P;;leaching loss risk;;fluvo-aquic soil
摘 要：
【Objectives】This study aimed to investigate the effect of phosphorus(P) fertilization on soil soluble P extracted by CaCl_2 solution(CaCl_2-P) in fluvo-aquic soils with different available P(Olsen-P) content and evaluate the leaching risk of soil P, in order to provide the theoretical reference on rational utilization of nutrients,reduction of chemical P fertilizer application and P loss from fluvo-aquic soils.【Methods】Five treatments with different Olsen-P content(0.8, 12.5, 25.7, 44.7, 56.4 mg/kg, here after referred as OP1, OP2, OP3, OP4, and OP5)from a long-term monitoring experiment were selected, and five rates of P fertilizer(F0, F1, F2, F3, and F4) were applied for each treatment. Micro-plots with random block design were established and a double cropping system was adopted in the experiment with both winter wheat and summer maize crops grown sequentially in every cropping year. After harvesting, soil samples were collected. Soil Olsen-P and CaCl_2-P contents were measured and the relationship between Olsen-P and CaCl_2-P was established.【Results】Soil CaCl_2-P content was in the range of 0.07-2.68 mg/kg, accounting for 0.5%-5.6% of the soil Olsen-P. High amount of P fertilization in the short term significantly enhanced soil Olsen-P and CaCl_2-P. However, the increment of Olsen-P and CaCl_2-P was not synchronous. When soil Olsen-P was lower than 28.0 mg/kg, the ratio of CaCl_2-P/Olsen-P decreased with the increase of Olsen-P, while the ratio of CaCl_2-P/Olsen-P increased rapidly after soil Olsen-P was increased to 28.0 mg/kg, indicating that P fertilizer increased soil Olsen-P first and CaCl_2-P increased rapidly after Olsen-P was increased to a certain level. The relationship between CaCl_2-P and Olsen-P was fitted well with line-line model,with the change-point of 30.2 mg/kg for Olsen-P and 0.3 mg/kg for CaCl_2-P, indicating that soil P leaching loss risk increased when soil Olsen-P was higher than 30.2 mg/kg.【Conclusions】High amount of P application improved soil CaCl_2-P content, which on one hand facilitated the P uptake of crops, but on the other hand increased the leaching loss risk of soil P. In the study area, the soil P leaching loss threshold was 30.2 mg/kg. Soil Olsen-P content was higher than 30.2 mg/kg in more than 50% of plots in the microplot experiment. Therefore,scientific application and management of P fertilizer should be strengthened to decrease the leaching loss risk of soil P.
