秸秆还田对土壤有机碳不同活性组分储量及分配的影响

应用生态学报

秸秆还田对土壤有机碳不同活性组分储量及分配的影响

王虎^1,2,王旭东^1,3**,田宵鸿^1,3

(¹西北农林科技大学资源环境学院, 陕西杨凌 712100; ^2杨凌职业技术学院, 陕西杨凌 712100; ^3农业部西北植物营养与农业环境重点实验室, 陕西杨凌 712100)

出版日期:2014-12-18 发布日期:2014-12-18

Effect of straw-returning on the storage and distribution of different active fractions of soil organic carbon.

WANG Hu^1,2, WANG Xu-dong^1,3, TIAN Xiao-hong^1,3

(¹College of Resources and Environment, Northwest A&F University, Yangling 712100, Shaanxi, China; ^2Yangling Vocational and Technical College, Yangling 712100, Shaanxi, China; ³Key Laboratory of Plant Nutrition and the Agrienvironment in Northwest China, Ministry of Agriculture, Yangling 712100, Shaanxi, China)

Online:2014-12-18 Published:2014-12-18

摘要/Abstract

摘要： 通过田间试验，研究了不同秸秆还田模式下土壤溶解性有机碳(DOC)、颗粒有机碳(POC)和矿物结合有机碳(MOC)储量及其在总有机碳(TOC)中的分配比例.结果表明: 相对于翻压还田(WR),小麦秸秆覆盖还田(WM)0～20 cm耕层TOC和MOC储量显著降低，降幅为4.1%和9.7%,DOC和POC储量显著提高，增幅为207.7%和11.9%;20～40 cm犁底层TOC和POC储量显著提高.玉米秸秆覆盖还田(MM)与MR相比,犁底层TOC和MOC储量显著提高,增幅为13.6%和14.6%.小麦-玉米秸秆均覆盖还田(WM-MM)相对于均翻压还田(WR-MR),耕层TOC和MOC储量显著降低,降幅为8.5%和10.3%.玉米秸秆还田耕层TOC和POC储量显著高于小麦秸秆还田.与对照(秸秆不还田)相比,6种还田模式耕层TOC储量增幅为5.2%～18.0%,差异达显著水平;除WM和MM模式外,犁底层TOC储量显著降低(降幅8.0%～11.5%).6种还田模式下土壤耕层DOC储量及DOC/TOC比值显著降低,在WM和WM-MM还田模式下耕层POC储量显著提高、POC/TOC比值增大,WR模式的耕层MOC储量显著提高、MOC/TOC比值增大,其余3种模式耕层POC和MOC储量均显著提高.秸秆覆盖还田有利于土壤有机碳活性组分积累,翻压还田有利于较稳定性有机碳组分积累.在提高关中地区农田TOC储量方面,玉米秸秆还田好于小麦秸秆还田、小麦-玉米秸秆翻压还田好于覆盖还田.

Abstract: The impacts of straw mulching and returning on the storage of soil dissolved organic carbon (DOC), particulate organic carbon (POC) and mineral associated organic carbon (MOC), and their proportions to the total organic carbon (TOC) were studied based on a field experiment. The results showed that compared to the treatment of wheat straw soilreturning (WR), the storage of TOC and MOC decreased by 4.1% and 9.7% respectively in 0-20 cm soil in the treatment with wheat straw mulching (WM), but the storage of DOC and POC increased by 207.7% and 11.9%, and TOC and POC increased significantly in 20-40 cm soil. Compared to the treatment with maize straw soilreturning (MR), the storage of TOC and MOC in the plough pan soil of the treatment with maize straw mulching (MM) increased by 13.6% and 14.6%, respectively. Compared to the WR-MR treatment, the storage of TOC and MOC in top soil (0-20 cm) significantly decreased by 8.5% and 10.3% respectively in WM-MM treatment. The storage of TOC and POC in top soil was significantly higher in the treatments with maize straw soilreturning or mulching than that with wheat straw. Compared to the treatment without straw (CK), the storage of TOC in top soil increased by 5.2% to 18.0% in the treatments with straw returning or mulching in the six modes (WM, WR, MM, MR, WM-MM,WR-MR)(P<0.05), but the storage of TOC in the plough pan soil decreased by 8.0% to 11.5% (P<0.05) except for the treatments of WM and MM. The storage of DOC and DOC/TOC ratio decreased significantly in top soil in the treatments with straw mulching or returning in six modes. The storage of POC and POC/TOC ratio in WM and WM-MM treatments, MOC and MOC/TOC ratio in WR treatment, increased significantly in top soil. In the other three treatments with straw mulching and returning (MM, MR, WR-MR), the storage of POC and MOC increased significantly in top soil. These results suggested that straw mulching had the potential to accumulate active organic carbon fraction in soil, straw soilreturning had the potential to accumulate stable organic carbon fraction. Considering organic carbon sequestration in cropland in the region of Guanzhong plain, maize straw mulching or soilreturning was better than wheat straw, and wheat straw and maize straw soilreturning (WR-MR) were better than wheat and maize straw mulching (WMMM).

王虎1,2,王旭东1,3**,田宵鸿1,3. 秸秆还田对土壤有机碳不同活性组分储量及分配的影响[J]. 应用生态学报.

WANG Hu1,2, WANG Xu-dong1,3, TIAN Xiao-hong1,3. Effect of straw-returning on the storage and distribution of different active fractions of soil organic carbon.[J]. Chinese Journal of Applied Ecology.