摘要
【目的】以河北省廊坊市小麦-玉米轮作区沙质潮土为研究对象,通过2015—2018年田间连续定位试验,研究两种土壤改良剂对土壤活性有机碳组分含量和土壤碳库管理指数的影响,以期为沙质潮土有机碳库培育,改善土壤质量提供理论依据。【方法】试验采用单因素随机区组设计,设4个处理:(1)单施化肥(CK);(2)CK+有机改良剂15 t·hm^-2(T1);(3)CK+无机改良剂2.25 t·hm^-2(T2);(4)CK+有机改良剂15 t·hm^-2+无机改良剂2.25t·hm^-2(T3)。收获季测定土壤有机碳、全氮、pH、速效磷、速效钾,并运用修正的内梅罗指数法计算土壤综合肥力指数(IFI)。再分析活性有机碳各组分含量,并计算碳库管理指数(CPMI)。最后通过CPMI和IFI指示指标评价连续施用土壤改良剂对沙质潮土改良的应用效果。【结果】较CK处理,施用有机改良剂处理土壤总有机碳(TOC)和土壤综合肥力指数(IFI)均显著提高,尤其是有机无机改良剂配施时效果最显著;施用有机改良剂处理各活性碳组分含量均呈升高趋势,并且活性有机碳各组分含量呈现为:易氧化有机碳(LOC)>可溶性有机碳(DOC)>微生物量碳(MBC);施用有机改良剂各处理土壤活性碳库组分有效率均呈下降趋势,T1、T3处理土壤易氧化有机碳有效率(LOC/TOC)较CK分别显著降低了12.57%和12.02%,微生物量碳有效率(MBC/TOC)较CK分别显著降低了12.84%和12.30%,单施无机改良剂处理较CK无显著影响,说明施用有机改良剂增加活性有机碳各组分含量的同时,向土壤中输入了更多的稳定态碳,进而导致有效率的降低;施用有机改良剂各处理土壤碳库指数显著升高、碳库活度显著降低,说明施用有机土壤改良剂能够促进土壤碳库的积累;施用有机改良剂各处理土壤碳库管理指数均呈升高趋势。主成分分析结果表明,施用有机改良剂能够影响土壤中活性碳各组分含量及其有效率。【结论】连续施用有机改良剂能够显著提高沙质潮土肥力,增加土壤碳库管理指数,累积碳库库容,改善土壤质量。
【Objective】Impacting of two soil amendments on the contents of active organic carbon components and soil carbon pool management index were studied from 2015 to 2018 in a sandy fluvo-aquic soil in Langfang City,Hebei Province under wheat-corn rotation.The purpose of the study was to provide a theoretical basis for the higher accumulation of organic carbon in sandy fluvo-aquic soil and for the improvement of soil quality.【Method】The experiment was carried out by a single factor randomized block design with four treatments:(1)chemical fertilizer only(CK),(2)CK+organic amendment 15 t·hm^-2(T1),(3)CK+inorganic amendment 2.25 t·hm^-2(T2),and(4)CK+organic amendment 15 t·hm^-2+inorganic amendment 2.25 t·hm^-2(T3).Soil organic matter content,total nitrogen,pH,available phosphorus and available potassium were measured to calculate soil integrated fertility index(IFI)by modified Nemero index method.Active organic carbon pools were also measured to calculate carbon pool management index(CPMI).Both IFI and CPMI were used to evaluate the soil amendments for the improvement of soil quality.【Result】The results showed that soil organic carbon(TOC)and IFI increased significantly under organic amendment comparing to CK,especially under the combination of organic with inorganic amendment(T3).The contents of active carbon pools increased under organic amendment,and was in the order of easily labile organic carbon(LOC)>dissolved organic carbon(DOC)>microbial biomass carbon(MBC).The ratio of active carbon pools to TOC decreased under organic amendment:the ratio of easily labile organic carbon to TOC(LOC/TOC)decreased significantly by 12.57%and 12.02%under T1 and T3,respectively;the ratio of microbial biomass carbon to TOC MBC/TOC decreased significantly by 12.84%and 12.30%under T1 and T3,respectively.Inorganic amendment(T2)had no effects on TOC and active carbon pools,therefore,the decreased ratios of active carbon pools to TOC mean that organic amendment increased stable TOC more than active carbon pools.The increase of CPMI and decrease of the ratio of soil carbon pools to TOC under organic amendment(T1 and T3)indicated that organic amendment resulted in the accumulation of organic carbon.The CPMI increased under the organic amendment.Principal component analysis showed that the organic amendment affected the composition and ratio of active carbon pools in the soil.【Conclusion】Continuous application of organic amendment significantly improved fertility of sandy fluvo-aquic soil,increased soil carbon pool management index and carbon storage capacity,and ultimately improved soil quality.
作者
周吉祥
张贺
杨静
李桂花
张建峰
ZHOU JiXiang;ZHANG He;YANG Jing;LI GuiHua;ZHANG JianFeng(National Engineering Laboratory of Cultivated Land Cultivation Technology,Institute of Agricultural Resources and Regional Planning,Chinese Academy of Agricultural Sciences,Beying 100081)
出处
《中国农业科学》
CAS
CSCD
北大核心
2020年第16期3307-3318,共12页
Scientia Agricultura Sinica
基金
国家自然科学基金(21577172)。
关键词
土壤改良剂
沙质潮土
肥力因子
土壤活性有机碳
碳库管理指数
soil amendment
sandy fluvo-aquic soil
fertility factor
soil active organic carbon
carbon pool management index