棉秆炭对灰漠土活性有机碳氮的影响

【目的】研究棉秆炭炭化条件对灰漠土土壤基本理化性质和活性有机碳氮的影响,为西北干旱区棉花秸秆生物炭在灰漠土土壤上改良和应用提供理论依据。【方法】采用室内恒温培养法,研究棉秆炭定量施入对灰漠土土壤基本理化性质和活性有机碳氮的影响。【结果】添加棉秆炭提高了土壤pH值、电导率和有机碳含量,相比CK处理分别提高了1.48%~2.65%、25.62%~39.61%和54.99%~213.09%;T₄H₀、T₄H₄、T₆H₀、T₆H₂和T₆H₄ 处理土壤微生物量氮较CK处理含量增加了67.73%、9.38%、95.49%、5.21%和6.90%,添加棉秆炭降低了土壤微生物量碳和CEC(T₄H₀除外)27.89%~49.50%和0.08%~5.12%,T₄H₁、T₆H₁、T₆H₄处理提高土壤可溶性有机碳总含量,其他处理降低了土壤可溶性有机碳总含量;随着炭化温度和炭化时间的增长,土壤pH值增加。炭化时间一致,炭化温度升高,降低土壤CEC、有机碳含量,提高土壤微生物量氮、可溶性有机碳含量,炭化处理间炭化时间过短或长(0.5、4 h)提高土壤微生物量碳。炭化温度高时(600℃),炭化时间影响土壤pH值和有机碳含量。【结论】低温短时间(450℃,1 h)制备的棉秆炭对灰漠土理化性质和活性有机碳氮变化影响较好,是较适宜的炭化处理。

Effects of Cotton Stalk Charcoal on Active Organic Carbon and Nitrogen in Ash Desert Soil

【Objective】 To study the effects of carbonization conditions of cotton stalk charcoal on the basic physiochemical properties and active organic carbon and nitrogen of ash desert soil in the hope of providing a theoretical basis for the improvement and application of cotton stalk biochar in ash desert soil in northwest China. 【Methods】 The effects of quantitative application of cotton stalk carbon on basic physiochemical properties and active organic carbon and nitrogen in ash desert soil were studied by indoor constant temperature culture method. 【Results】 Adding cotton stem carbon increased soil pH value, electrical conductivity and organic carbon content, which were increased by 1.48%-2.65%, 25.62%-39.61% and 54.99%-213.09% compared with CK, respectively. Soil microbial biomass nitrogen in some treatments (H₀, H₄ and T6H₂) was increased by 5.21%-95.49% compared with CK, and soil microbial biomass carbon and CEC (except T₄H₀)were decreased by 27.89-49.50% and 0.08%-5.12%, respectively.T₄H₁, T₆H₁ and T₆H₄ treatments increased the total soil soluble organic carbon content, while other treatments decreased the total soil soluble organic carbon content. With the increase of carbonization temperature and carbonization time, the soil pH value increased. The carbonization time was the same, the carbonization temperature increased, the soil CEC and organic carbon content decreased, and the soil microbial biomass nitrogen and soluble organic carbon content increased. The carbonization time was too short or too long (0.5 h, 4 h) between the carbonization treatments to increase the soil microbial biomass carbon. When the carbonization temperature was high (600℃), the carbonization time affected the soil pH value and organic carbon content. 【Conclusion】 Based on the comprehensive analysis, the cotton stalk charcoal prepared at low temperature for a short time (450℃, 1h) has a good effect on the physiochemical properties and the changes of active organic carbon and nitrogen of ash desert soil, and it is a more suitable carbonization treatment.