有机物料添加对内蒙古河套灌区碱化土壤可溶性有机碳的影响

通过研究不同有机物料添加对内蒙古河套灌区碱化土壤可溶性有机碳含量变化的影响，寻找合理高效的增碳方式，降低碱化土壤有机碳损失。以内蒙古河套灌区轻度、中度盐碱土为对象进行田间试验，设置生物炭（BC）添加、羊粪（GM）添加，对照（CK）3个处理，对比和分析不同有机物料添加后土壤有机碳（SOC）、可溶性有机碳（DOC）、土壤理化性质的变化。结果表明：（1）与CK相比，轻度碱化土壤BC、GM处理土壤DOC含量分别增加3.28%，20.66%，SOC含量增加5.40%，10.30%，中度碱化土壤BC和GM处理下可溶性碳增加41.32%，74.10%，土壤SOC含量增加60.24%，79.16%；（2）轻度碱化土壤BC和GM处理土壤DOC含量与SOC含量呈负相关，中度碱化土壤BC和GM处理下呈正相关；（3）盐碱土壤SOC、DOC含量主要与土壤pH、电导率的变化有关；BC处理较GM处理相比土壤电导率低约1.93%~29.15%，而GM处理土壤pH、碱化度比BC处理低0.31%~1.53%，7.10%~24.63%。总体来看，有机物料添加后均能使土壤中SOC、DOC含量提高，不同程度地降低土壤碱化程度，且羊粪添加较生物炭略好，因此羊粪添加对河套灌区碱化土壤碳含量的提高比生物炭添加更有效，土壤改良效果更好，土壤理化性质改善更明显。

Effects of Organic Material Addition on Dissolved Organic Carbon in Alkali Soil in Hetao Irrigation District of Inner Mongolia

In order to find a reasonable and efficient mode of carburizing and reduce the loss of organic carbon in alkalized soil, the effect of different organic materials addition on the capacity of dissolved organic carbon in saline-alkali soil of Hetao Irrigation District in Inner Mongolia had been studied. Taking mild and moderate saline-alkali soil in Hetao Irrigation District of Inner Mongolia as the objects to carry out field trials, the three treatments of biochar (BC), goat manure (GM), and CK were used to compare and analyze the changes of soil organic carbon (SOC), dissolved organic carbon (DOC), and soil physio-chemical properties after adding different organic materials. The results showed that: (1) compared with CK, the DOC capacity treated by BC and GM in mild alkalized soil has increased by 3.28% and 20.66%, the SOC capacity has increased by 5.40% and 10.30%, respectively. The capacity of dissolved carbon treated by BC and GM in moderate alkalized soil had increased by 41.32% and 74.10%, and the SOC capacity had increased by 60.24% and 79.16%, respectively. (2) There was a negative correlation between DOC capacity and SOC capacity treated by BC and GM in mild alkalized soil, and a positive correlation between DOC capacity and SOC capacity treated by BC and GM in moderate alkalized soil. (3) The capacity of SOC and DOC in saline-alkali soil was mainly related to the change of soil pH and conductivity, compared with the treatment of GM, the conductivity of BC was about 1.93%~29.15% lower, while the soil pH and alkalinity of GM was 0.31%~1.53% and 7.10%~24.63% lower than that of BC, respectively. In general, the addition of organic materials could increase the capacity of SOC and DOC in the soil, and reduced the degree of soil alkalization, and the addition of GM was slightly better than that of BC. Therefore, compared with BC, GM was more effective to improve the carbon capacity of alkalization soil in Hetao Irrigation District, the effect of soil amendment was better, and the improvement of soil physio-chemical properties was more obvious.