免耕覆盖与生物炭对黑垆土团聚体稳定性和腐殖质性质的影响  

Effects of no-tillage mulching and biochar application on the stability and humus properties of black loam soil aggregate

作　　者：周明星 樊军[1,2,3] 王茜 代子俊 苟国花 ZHOU Ming-xing;FAN Jun;WANG Xi;DAI Zi-jun;GOU Guo-hua(State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau,Northwest A&F University,Yangling,Shaanxi 712100,China;College of Natural Resources and Environment,Northwest A&F University,Yangling,Shaanxi 712100,China;Institute of Soil and Water Conservation,Chinese Academy of Sciences and Ministry of Water Resources,Yangling,Shaanxi 712100,China)

机构地区：[1]西北农林科技大学黄土高原土壤侵蚀与旱地农业国家重点实验室,陕西杨凌712100 [2]西北农林科技大学资源环境学院,陕西杨凌712100 [3]中国科学院水利部水土保持研究所,陕西杨凌712100

出　　处：《植物营养与肥料学报》2023年第5期848-859,共12页Journal of Plant Nutrition and Fertilizers

基　　金：中国科学院战略性先导科技专项(XDA23070202);国家自然科学基金面上项目(41977016)。

摘　　要：【目的】研究免耕条件下,长期采用不同的土壤覆盖方式及配合施用生物炭对渭北旱塬农田土壤团聚体稳定性和腐殖质性质的影响,为选择适合的耕作管理措施提供理论依据。【方法】基于连续18年田间定位试验,选择其中免耕条件下的无覆盖(NT)、施用生物炭(NB)、秸秆覆盖(NS)、地膜覆盖(NP)、秸秆地膜二元覆盖(NSP) 5个处理,采集0—10、10—20 cm土层土壤样品,通过干筛+湿筛法分为粉黏粒(<0.053 mm)、微团聚体(0.053~0.25 mm)、细大团聚体(0.25~2 mm)、粗大团聚体(>2 mm)共4个团聚体粒级,并测定了各粒级团聚体中有机碳和腐殖质组分含量。【结果】1)与NT处理相比,NS处理各粒径团聚体胡敏酸含量(0.93%~92.6%)和富里酸含量(1.8%~327.5%)显著增加且增幅最大,NSP处理各粒径团聚体有机碳含量显著提高了1.6%~30.5%;NB处理各粒径团聚体有机碳含量(39.90%~161.8%)及胡敏素含量的增幅最大,0—10 cm土层胡敏素含量显著提高了87.2%~271.7%。与NT相比,NS、NSP和NB处理均提高了土壤团聚体的稳定性和玉米籽粒产量,其中NSP处理的提升效果最显著,0—10、10—20 cm土层土壤团聚体平均重量直径(MWD)分别增加了48.6%和73.5%,几何平均直径(GMD)分别增加了59.2%和63.1%,2021年玉米籽粒产量增加了25.8%。2)各粒径水稳性团聚体有机碳中,均以胡敏素的比例最高,达37.6%~91.3%。与NT相比,NB处理显著提高了大部分粒径水稳性团聚体腐殖质的胡敏酸与富里酸之比(HA/FA),其中在0—10 cm土层微团聚体提高幅度最大,为80.2%,地膜覆盖(NP和NSP处理)降低了腐殖质HA/FA (6.8%~27.6%),各处理粉黏粒胡敏酸E4/E6值显著降低(4.2%~6.6%)。【结论】免耕条件下,秸秆覆盖和施用生物炭(NS、NSP和NB)可提升各粒径团聚体的有机碳含量,提高团聚体的稳定性和玉米产量,但对有机碳的腐殖化程度影响不同。单独秸秆覆盖提升黑垆土腐殖质的胡敏酸和富里酸含量【Objectives】We studied the effects of different soil mulching methods and biochar addition on soil aggregate stability and humus properties under no-tillage conditions in Weibei dryland.We aim to provide a theoretical basis for selecting suitable farming management measures.【Methods】The field experiment lasted 18 consecutive years;we collected soil samples at 0−10 cm and 10−20 cm depth from the five no-tillage treatments,namely,no mulching control(NT),biochar application(NB),straw mulching(NS),plastic film mulching(NP),and straw plastic film binary mulching(NSP).Dry-sieving and wet-sieving methods were used to divide the soil aggregate into four fractions:silty-clay(<0.053 mm),microaggregate(0.053−0.25mm),macroaggregate(0.25−2 mm),and large macroaggregate(>2 mm),and the contents of organic carbon and humus components in the aggregates of each fraction were determined.【Results】1)Compared with NT,NS had the highest humin acid content(0.93%−92.6%)and fulvic acid content(1.8%−327.5%)across the four aggregate sizes;NSP increased the organic carbon by 1.6%−30.5%;organic carbon increased by 39.9%−161.8%in soil aggregate of NB treatment NB recorded a higher increase in humin content in 0−10 cm soil layer(87.2%−271.7%).NB,NS,and NSP improved soil aggregate stability and maize seed yield,with the most remarkable effect recorded for NSP.Compared with NT,NSP increased the mean weight diameter(MWD)of soil aggregate in 0−10 cm and 10−20 cm soil layers by 48.6%and 73.5%,the geometric mean diameter(GMD)in 0−10 cm and 10−20 cm soil layers by 59.2%and 63.1%,and the corn grain yield by 25.8%in 2021.2)Humin was dominant in the organic carbon,accounting for 37.6%−91.3%of the total organic carbon in the water-stable aggregates in different particle sizes.NB(P<0.05)increased the ratio of humic to fulvic acid(HA/FA)in most water-stable aggregates,with the maximum increase(80.2%)recorded in micro-aggregates in 0−10 cm soil layer.Plastic film mulching(NP and NSP)decreased the HA/FA of humus(6.8%

关 键 词：团聚体稳定性 腐殖质 E4/E6 H/F 黑垆土 秸秆覆盖 地膜覆盖 生物炭 

分 类 号：S152[农业科学—土壤学]