秸秆和生物炭添加量及比例对华北下沉式设施菜田土壤CO_(2)排放的影响  

Effects of Additive Amounts and Ratios of Straw and Biochar on CO_(2) Emissions from the Soil of Sunken Vegetable Fields in North China

作　　者：王亚芳 赵以铭 李英杰 徐梓楷 李国元 王敬国[1] 林杉[1,2] WANG Ya-fang;ZHAO Yi-ming;LI Ying-jie(College of Resources and Environmental Sciences,China Agricultural University,Beijing 100193)

机构地区：[1]中国农业大学资源与环境学院,北京100193 [2]湖北工程学院生命科学技术学院(农学院),湖北孝感432000

出　　处：《安徽农业科学》2021年第21期85-90,共6页Journal of Anhui Agricultural Sciences

基　　金：国家自然科学基金国际合作项目(41761134087);湖北省科技厅重大专项(2019ABA117);国家科技支撑计划项目(2015BAD23B01-4)。

摘　　要：通过2组室内培养试验,研究玉米秸秆和生物炭添加量及其添加比例对设施菜田土壤有机碳矿化的影响。试验1为2因素4水平试验设计,主因素为有机碳源种类,即玉米秸秆、生物炭;副因素为碳添加量,分别为0、1.31、2.62、5.24 g/kg土壤(按碳量)。试验2为单因素试验设计,除对照外,有机碳添加量均为5.24 g/kg土壤,将玉米秸秆(S)和生物炭(B)按不同比例与土壤混合,添加比例分别为100%S、75%S+25%B、50%S+50%B、25%S+75%B、100%B、0S0B(对照)。培养期间,维持土壤含水量为田间最大持水量的65%,测定和计算培养期间土壤CO_(2)日均排放通量、累积排放量和排放率、土壤微生物量碳含量。结果表明,与施用生物炭相比,施用等碳量秸秆显著增加了CO_(2)累积排放量,其增幅为50%~337%;与不施用有机物料的对照相比,随着秸秆施用量增加,CO_(2)累积排放量显著增加了92%~463%,而随着生物炭施用量增加,其增幅仅为28%~39%。培养前30 d内,CO_(2)日均排放通量和累积排放量最高,其后逐渐降低,趋于平缓。随着秸秆添加比例降低和生物炭添加比例增加,CO_(2)日均和累积排放量、排放率和土壤微生物量碳含量显著减少;随着培养时间延长,CO_(2)日均排放通量逐渐降低,而累积排放量则逐渐增加。总之,将秸秆与生物炭按比例混合施用,一方面秸秆矿化过程产生的CO_(2)能够满足秋冬茬设施蔬菜对CO_(2)的高需求;另一方面,生物炭可以快速提升土壤碳储量,并且可以避免蔬菜残茬直接还田可能造成土传病害的扩散,有利于设施菜田土壤-植物碳循环和生产体系的可持续性。然而,上述研究结果仍需在大田条件下进一步验证,并根据种植茬口和土壤环境条件调整秸秆和生物炭添加量及其比例。Two laboratory incubation experiments were conducted to investigate the effects of additive amounts and ratios of maize straw and biochar on soil respiration.Experiment I included two-factors with four-level.The main factor was kinds of organic material,namely corn straw and biochar.The second factor was application amount which were 0,1.31,2.62 and 5.24 g/kg(according to carbon amount),respectively.Experiment II deal with the effect of application ratio of maize straw(S)and biochar(B)which included six treatments:100%S,75%S+25%B,50%S+50%B,25%S+75%B,100%B,0S0B(control).During the incubation period,soil water content was maitained at the 65%of field capacity.Daily CO_(2) emissions were measured and soil microbial carbon contents were analyzed at the end of incubation for experiment II.The result showed that compared with biochar addtion,application of maize straw at the same carbon addtion rate siginificantly increased soil CO_(2) emissions by 50%-337%.Compared with control,cumulative CO_(2) emissions increased with the increasing of straw addition rate(increaed by 92%-463%),whereas the biochar just increased cumulative CO_(2) emissions by 28%-39%.Within the first 30 days of incubation,daily CO_(2) emissions and cumulative CO_(2) emissions were highest over the whole incubation period and then decreased slowly.With the decreased addtion ratios of straw and increased addtion ratios of biochar,daily CO_(2) emissions,cumulative CO_(2) emissions,CO_(2) emission rates and soil microbial carbon content decreased siginificantly.Daily CO_(2) emissions decreased with the incubation days,while cumulative CO_(2) emissions increased.Our results highlight that incorporation of straw and biochar is an effective measure to increase soil resipiraiton and facilitate greenhouse CO_(2) limitation.On the other hand,addition of biochar will increase soil organic carbon stock.Therefore,simultanouesly application of maize straw and biochar is an effective option to maintain the sustainable development of greenhouse vegetable production.

关 键 词：设施菜田 玉米秸秆 生物炭 添加量 比例 CO_(2)排放 下沉式设施大棚 

分 类 号：S152.6[农业科学—土壤学]