摘要
【目的】生物碳可提高土壤肥力,增强土壤对养分的保持能力,减少养分损失,提高肥料利用率。研究不同温度热解制备的生物碳对棉花生长和肥料利用率的差异,可以为提高生物碳的有效利用提供依据。【方法】供试生物碳由棉花秸秆分别在450℃、600℃和750℃高温限氧条件下热解制备而成。本试验为两因素(生物碳、氮)温室盆栽试验,生物碳处理包括3种不同热解温度生物碳处理(分别以450BC、600BC、750BC表示)和1个空白对照(CK);每个生物碳土壤设置3个施氮水平0、2.1和4.2 g/pot(分别以N0、N1、N2表示),用15N同位素示踪方法分析不同施氮水平下3种热解温度生物碳对棉花生长、15N回收和淋洗损失的影响。【结果】1)施用3种生物碳处理棉花干物质重总体表现为750BC>600BC、450BC>CK,450BC、600BC和750BC处理分别较对照平均增加了9.2%、12.6%和17.3%;并且棉花总干物质重随施氮量的增加而增加,但生物碳作用随之降低;2)3种生物碳处理棉花氮素吸收总量总体也表现为750BC>600BC、450BC>CK。不施氮肥条件下(N0),600BC和750BC处理棉花氮素吸收总量显著高于CK,但450BC处理与与CK无显著差异;施氮肥条件下(N1、N2),3种生物碳处理均显著高于CK,450BC、600BC和750BC处理棉花氮素吸收总量平均较CK分别增加29.5%、37.1%和48.8%;3)15N标记试验结果表明,450BC、600BC和750BC处理植株15N回收率显著高于对照,分别较CK平均提高27.46%、36.44%和42.87%。而N1和N2水平下3种生物碳处理之间植株15N回收率均没有显著差异;4)450BC、600BC和750BC处理土壤15N残留率分别较对照平均增加101.4%、147.3%和200.7%。土壤15N残留率在N1水平下随着生物碳热解温度的升高而增加,而在N2水平下750BC处理显著高于450BC和600BC处理,但是后二者之间没有显著差异。土壤15N残留率随着施氮量的增加而降低;5)施用生物碳可以显著降低土壤15N的淋洗,并且不同施氮水平下(N1、N2)淋洗率都随着生物碳热解温度的升高而降低。【结论】施用生物碳可促进棉花生长,增加棉花氮素吸收,提高氮肥利用率,降低氮素损失,并且生物碳的热解温度越高效果越明显;但是随着氮肥施用量的增加生物碳作用减弱。
【Objectives 】 Biochar are found having efficacy of retaining ions and reducing nutrient loss when applied into soils. The differences of their beneficial effects of biochar made in different temperatures were studied to provide a base for efficient biochar manufacture and reasonable use in cotton production. And the effect of three N fertilizer rates on cotton growth,N use efficiency and N leaching was studied using15 N tracer techniques.【Methods】Cotton straw was thermodynamic decomposed to make biochar at 450℃( 450BC),600℃( 600BC) and750℃( 750BC),respectively. A two-factor pot experiment was designed using the three kinds of biochar and threelevels of nitrogen. The three kinds of biochar recorded as 450 BC,600BC and 750 BC,with no biochar addition as control( CK). In each kind of biochar treatment,three levels of15 N labeled nitrogen fertilizer: 0( N0),2. 1( N1)and 4. 2 g / pot( N2) were added. The biomass and yield of cotton and the N use efficiency were measured.【Results】1) The cotton dry weights were generally increased in order of 750 BC > 600BC、450BC > CK,the increase in cotton dry weights was averaged 9. 2% in the 450 BC treatments,12. 6% in 600 BC treatments and17. 3% in the 750 BC treatments. The cotton dry weights increased with the increased rate of N application. 2) The N uptake in cotton was generally increased,and the increase in the 750 BC treatments was higher than in 600 BC treatments,and also higher than in 450 BC treatments regardless of the N application rates. When the N rate was N0,the nitrogen uptakes in the cotton in both the 750 BC and the 600 BC treatments were significantly higher than in CK,not significantly higher than in 450 BC treatment. The input of N increased the N uptake in cotton in all the biochar treatments. The biochar addition averagely increased the N uptake by 29. 5% in 450 BC treatments,37. 1%in 600 BC treatments,and 48. 8% in 750 BC treatments,respectively. 3) The15 N tracer data showed that compared with the CK treatment,plant15 N recovery in the 450 BC treatment increased by 27. 46% and plant15 N recovery in the 600 BC treatment increased by 36. 44%,and plant15 N recovery in the 750 BC treatment increased by 42. 87%.But in two N rates( N1,N2),there were no significant difference among the three biochar treatments. 4) Soil15 N recovery in the 450 BC treatment increased by 101. 4%,and 147. 3% in the 600 BC treatment,and 200. 7% in the750 BC treatment relative to the CK treatment. In case of lower N rates( N1),soil15 N recovery increased as the biochar pyrolysis temperature increased. In N2 treatments,the soil15 N recovery in the 750 BC was significantly higher than in both the 450 BC and the 600 BC treatments,but the difference between the 600 BC treatment and the450 BC treatment was not significant. Soil15 N recovery decreased as N application rate increased in all three biochar amended treatments. 5) The15 N leaching in the biochar amended treatments was significantly lower than that in the CK treatment. Furthermore,15 N leaching decreased as the biochar pyrolysis temperature increased.【Conclusions】The beneficial effects of biochar increase as the pyrolysis temperature increased,and decrease as the N application rate increased. Therefore,cotton straws are recommended to be treated at high temperature,and the N input should be reduced for the maximum positive effects of biochar on crop growth and N use efficiency.
出处
《植物营养与肥料学报》
CAS
CSCD
北大核心
2015年第3期600-607,共8页
Journal of Plant Nutrition and Fertilizers
基金
国家自然科学基金(31160415)
新疆生产建设兵团杰出青年创新资金专项(2014CD002)资助
关键词
生物碳
制备温度
棉花
氮素吸收
氮肥利用率
biochar
preparation temperature
cotton
nitrogen uptake
nitrogen use efficiency
