摘要
【目的】土壤有机碳作为土壤肥力的核心,其不同组分间具有高度异质性。研究不同施肥措施对煤矿区复垦土壤有机碳及其各组分提升的差异特征,可为煤矿区土壤修复提供理论依据。【方法】田间试验在山西煤矿复垦区进行,复垦始于2014年,种植作物为大豆(1年)和玉米(2年)轮作,采样时(2018年)种植作物为玉米。试验共设5个处理分别为未复垦自然恢复(ZH)、不施肥(CK)、单施化肥(NPK)、单施有机肥(M)和有机肥配施化肥(MNPK)。使用物理-化学联合分组方法,将土壤有机碳分为游离活性、物理保护、化学保护和生物化学保护4个组分,分析了不同施肥处理下土壤各组分有机碳的含量,计算了各组分有机碳与总有机碳含量间的相关关系。【结果】相较于自然恢复处理,CK、NPK、M、MNPK处理中土壤总有机碳含量分别提高了11.8%、24.0%、49.3%和38.8%,有机肥处理又显著高于CK和NPK处理。M、MNPK处理下,游离活性有机碳含量分别为2.11和1.68 g/kg,物理保护有机碳含量分别为0.70和0.49 g/kg,均显著高于CK和NPK处理;化学保护和生物化学保护组分的有机碳含量在各处理间差异不显著。除了微团聚体内的轻组和粘、粉粒外,各组分质量比例在不同施肥处理间均存在显著差异,施用有机肥主要增加了大团聚体(游离活性态和物理保护态)的质量比例,改善了土壤结构。相关分析表明,游离态的粗颗粒和细颗粒有机碳及物理保护有机碳与总有机碳含量间呈现极显著正相关关系(P<0.01),其中拟合方程的斜率表示组分碳含量随单位总有机碳含量增加而引起的变化值,最高的为游离粗颗粒有机碳组分,达到39.7%,游离细颗粒和物理保护有机碳组分的变化率分别为18.6%和21.7%;而化学保护粘、粉粒和生物化学保护粘粒组有机碳与总有机碳含量无显著相关性。【结论】施肥和轮作与自然恢复状态相比,短期可显著提高土壤有机碳含量,施用有机肥效果好于单施化肥。单施或者与NPK配合施有机肥主要促进了土壤大团聚体中游离活性态和物理保护态有机碳含量的提升,单施有机肥效果更佳。由于新增的土壤有机碳活性高,需要长时间持续投入才可能恢复土壤有机碳的稳定性。
【Objectives】Soil organic carbon is the core of soil fertility,the fractions of organic carbon are highly heterogeneous.We studied the promotion effect of fertilization on different organic carbon fractions to provide theoretical basis for efficient remediation of coal mining soil.【Methods】A field experiment was conducted in the coal mining reclamation soil in Shanxi Province since 2014.The planting system was rotation of one-year-soybean with two-year-maize.Five fertilization treatments included natural recovery(ZH),no fertilization(CK),chemical fertilizer(NPK),organic manure(M),manure combined with chemical fertilizer(MNPK).In the 2018 maize season,0-20 cm top soil samples were collected.Using the physical-chemical fractionation methods,the soil organic carbon were classified into four fractions:unprotected fractions,physical protective fractions,chemical protective fractions and biochemical protective fractions.The saturation trend of soil organic carbon by analyzing the correlation between the fractions carbon and the total organic carbon content.【Results】Compared with natural reclamation,rotation significantly increased the soil total organic carbon content(P<0.05).Soil total organic carbon increased by 11.8%,24.0%,38.8%and 49.3%respectively in CK,NPK,M and MNPK treatments,and M and MNPK trenaments were significantly higher than in CK and NPK treatments.Of the total organic C in M and MNPK treatments,the unprotected organic C were2.11 g/kg and 1.68 g/kg and the physically protected organic C were 0.70 g/kg and 0.49 g/kg,respectively,which were significantly higher than in CK and NPK treatments;while the chemically protected organic C and biochemical protection organic C content were not significantly different among the four treatments.The quality ratios of each fraction in M and MNPK treatments were not significantly different with the CK and NKP treatments in the light fraction,silt and clay in the micro-aggregate,but significantly in the large aggregates(unprotected and physically-protected).The organic C in unprotected coarse and fine particles and the physically protected organic C were all significantly and positively correlated with the total organic C content(P<0.01).According to the slope of the fitted equation,with the increase of total organic C per unit,the highest increase rate in the four fractions was the unprotected coarse particle organic C(39.7%),then were the unprotected fine particulate organic C(18.6%)and physically protected organic C(21.7%),respectively.The relationship between the silt and clay of chemical protection fractions C and the clay of biochemical protection fractions C were not significant with the total organic C.【Conclusions】Fertilization and crop rotation are more effective than natural recovery in rapid increase of soil organic carbon contents,manure are more effective than pure NPK fertilization.Single and combined application of manure with NPK could increase the coarse aggregates contents,i.e.increase the friable unprotected coarse and fine particle C and physically protected C,and single manure application performs better than with NPK together.However,as the newly increased soil carbon are quite active,so longterm organic manure input is necessary for the recovery of soil function in coal mine reclamation.
作者
安永齐
王小利
靳东升
郜春花
张强
洪坚平
徐明岗
AN Yong-qi;WANG Xiao-li;JIN Dong-shen;GAO Chun-hua;ZHANG Qiang;HONG Jian-ping;XU Ming-gang(College of Agriculture,Guizhou University,Guiyang 550025,China;Institute of Agricultural Resources and Regional Planning,Chinese Academy of Agricultural Sciences(CAAS)/National Engineering Laboratory for Improving Quality of Arable Land,Beijing 100081,China;Institute of Agricultural Environment and Resources,Shanxi Academy of Agricultural Sciences,Taiyuan 030031,China;College of Resources and Environment,Shanxi Agricultural University,Taigu,Shanxi 030801,China)
出处
《植物营养与肥料学报》
CAS
CSCD
北大核心
2020年第6期1117-1125,共9页
Journal of Plant Nutrition and Fertilizers
基金
国家自然科学基金联合基金(U1710255)
国家自然科学基金项目(31860160)。
关键词
煤矿区复垦土壤
土壤有机碳
物理–化学联合分组
有机碳组分
土壤碳固定
coal mining reclamation soil
soil organic carbon
physical-chemical fractionation
organic carbon fractions
soil carbon sequestration
