【摘要】：可溶性有機(jī)碳(DOC)吸附影響土壤元素化學(xué)行為。為此,本研究采用批處理法研究了DOC在長期不同施肥處理(對照CK、氮N、氮磷NP、氮磷鉀NPK、化肥+秸稈還田NPKS、化肥+有機(jī)肥NPKM)潮土上的吸附動力學(xué)和等溫吸附特征。結(jié)果表明,豬糞源DOC易于分解,需要添加0.025 mmol(1 mL 25 mmol/L)Na N3抑制其分解,抑制率超過90%。DOC吸附符合準(zhǔn)二級動力學(xué)方程(R~2≥0.99)。不同施肥處理下,吸附速率常數(shù)k及初始速率常數(shù)h與平衡吸附Qe都沒有顯著差異,平均值分別為0.208 kg/(g·h)、1.60 g/(kg·h)和2.77g/kg。吸附等溫式可用Langmuir方程很好擬合(R~2≥0.96),吸附容量(最大吸附量)Q_(max)在不同施肥處理下也沒有顯著差異(平均7.05 g/kg),但在N和NP等非平衡施肥下卻保持高的親合力,半飽和吸附濃度k_d分別為50.2和57.6 mg/L,吸附親合常數(shù)K則分別為0.02和0.017 4 L/mg;相反,在NPKM處理下,顯著低的親合性發(fā)生,k_d和K分別為72.94 mg/L和0.013 8 L/mg。研究證明粘粉粒含量控制了不同施肥處理潮土對DOC的吸附;土壤有機(jī)碳水平不影響Q_(max),而且高土壤有機(jī)碳還降低其吸附親合性。
[Abstract]:The adsorption of soluble organic carbon (DOC) affected the chemical behavior of soil elements. For this reason, the adsorption kinetics and isothermal adsorption characteristics of DOC on the fluvo-aquic soil treated with long-term fertilization (CK, N, P, NP, N, P, K, NPK, NPKM) were studied by batch treatment. The results showed that DOC from pig manure was easy to decompose, and 0.025 mmol (1 mL 25 mmol/L) Na N3 was added to inhibit the decomposition, and the inhibition rate was higher than that of 90%.DOC adsorption in accordance with the quasi second order kinetic equation (RN 2 鈮，

本文編號：2364930