盐分与有机无机肥配施对土壤氮素矿化的影响  

Effect of Salt and Organic-Inorganic Fertilizer Application on Soil Nitrogen Mineralization

作　　者：周慧 史海滨[1] 郭珈玮 徐昭[1] 付小军 李正中 ZHOU Hui;SHI Haibin;GUO Jiawei;XU Zhao;FU Xiaojun;LI Zhengzhong(College of Water Conservancy and Civil Engineering,Inner Mongolia Agricultural University,Huhhot 010018,China;Shahaoqu Irrigation Experimental Station,Jiefangzha Management Bureau of Hetao Irrigation District,Bayannur 015400,China)

机构地区：[1]内蒙古农业大学水利与土木建筑工程学院,呼和浩特010018 [2]内蒙古河套灌区解放闸灌域管理局沙壕渠试验站,巴彦淖尔015400

出　　处：《农业机械学报》2020年第5期295-304,共10页Transactions of the Chinese Society for Agricultural Machinery

基　　金：国家自然科学基金重点项目(51539005);国家自然科学基金项目(51769024);国家重点研发计划项目(2016YFC0400205);内蒙古自治区科技计划项目(201602049)。

摘　　要：针对有机无机肥配施在不同土壤盐分水平下所产生的氮素矿化过程,通过室内恒温培养试验,分别在4种盐分水平(0.46、0.98、1.55、1.97 dS/m)下,以0.0895 g/kg(纯氮施用量与风干土质量比)为相同施氮总量设置5个施肥处理(有机肥占施肥比例分别为0、25%、50%、75%、100%)及1个不施肥处理,研究了不同盐分水平下有机无机肥料配施对土壤净氨化量、净硝化量及净氮矿化量的影响。结果表明,土壤盐分含量随有机肥施入比例的增大而减小;盐分水平的增加对无机肥氨化作用的抑制较为强烈,当土壤电导率小于0.98 dS/m时,增施有机肥会减弱盐分对氨化作用的影响,而电导率升至1.55 dS/m以上时,则明显延缓有机肥氨化过程,但并不会完全抑制。盐分水平对土壤NO^-3-N生成速率的影响有一个阈值,当土壤电导率小于0.98 dS/m时,随着盐分水平的升高,NO^-3-N增加速率上升;而盐分水平继续升高,则抑制土壤NO^-3-N的形成速率。相比不施肥,施肥显著提高了各盐分土壤净氮矿化量,同一盐分水平下均表现出无机肥施入比例越大、净氮矿化量越大的趋势。相较0.46 dS/m,增施有机肥减小了0.98 dS/m盐分水平下各处理之间净氮矿化量差异,而土壤电导率增至1.55 dS/m及以上时,盐分水平对有机肥矿化过程产生明显的延缓作用。综合有机无机肥料配施对土壤盐分及氮素矿化过程的影响,推荐不同盐分水平下适宜的施肥模式为:50%有机肥+50%化肥(非盐渍化土壤)、100%有机肥(轻度盐渍化土壤)、25%有机肥+75%化肥(中度及重度盐渍化土壤)。Nitrogen mineralization is an important ecological process that determines ability of soil nitrogen supply.In order to provide theoretical basis for efficient fertilizer application in salinized soil,the effect of organic and inorganic fertilizers on the soil net nitrification,ammonification and nitrogen mineralization under different soil salinity were determined.By laboratory aerobic incubation,under four salt levels(0.46 dS/m,0.98 dS/m,1.55 dS/m and 1.97 dS/m),the same amount of nitrogen of 0.0895 g/kg(dry weights of pure fertilizer/dry weights of purple soil)was applied to different treatments,and five fertilization treatments(the fertilization proportion of the organic fertilizer was 0,25%,50%,75%and 100%,respectively)and one blank control were provided,which were designated as U1,U3O1,U1O1,U1O3,O1 and CK,respectively.Main conclusions were as follows:soil salt concentration was decreased with the increase of proportion of organic fertilizer applied;the increase of salt content had a strong inhibition on the amination of inorganic fertilizer.When the EC was less than 0.98 dS/m,the application of organic fertilizer would reduce the effect of salt on amination,while when the EC was raised above 1.55 dS/m,it would obviously delay the amination process of organic fertilizer,but it would not be completely suppressed.There was a threshold value for the effect of salinity on the formation rate of NO^-3-N.When the EC was less than 0.98 dS/m,the increase rate of NO^-3-N was increased with the increase of salinity level,while the continuous increase of salinity would inhibit the formation rate of NO^-3-N.Compared with no fertilizer,fertilizer significantly increased the amount of net nitrogen mineralization in each salt soil,and the same salt level showed that the larger proportion of inorganic fertilizer was applied,the greater amount of net nitrogen mineralization was.Compared with the application of organic fertilizer under 0.46 dS/m,the difference of net nitrogen mineralization between the treatments under 0.98 dS/

关 键 词：土壤盐分 有机无机肥配施比例 铵态氮 硝态氮 矿化 

分 类 号：S153.6[农业科学—土壤学]