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耕作历史和种植方式是影响黑河绿洲农田土壤总有机碳及其组成的重要因素。研究结果显示,随着耕作时间的延长,土壤总有机碳(TOC)、活性有机碳(AOC)、惰性有机碳(NOC)的含量均呈增加趋势,但AOC、NOC的增幅存在差异,AOC因性质活泼,对农业活动等措施引起的变化较NOC有较快响应,因此,在耕作的初期(0～5 a),AOC的增幅高于NOC,而20 a的耕地NOC增幅大于AOC,之后达到AOC与NOC的增幅接近(>100 a)的动态发展趋势,表明总有机碳含量积累的过程是AOC与NOC增幅逐渐接近、NOC积累增速的过程。>100 a的耕地,因种植方式不同,剖面上TOC、AOC、NOC含量呈现出:油菜地>普通玉米地>制种玉米地>小麦地。分析发现,绿洲区近年来大面积种植制种玉米引起TOC、AOC、NOC发生改变,增加秸秆或牲畜粪便的归还量是提高土壤有机碳的有效途径。
Tillage history and cultivation methods are important factors that affect soil total organic carbon and its composition in Heihe oasis farmland. The results showed that the contents of total organic carbon (TOC), active organic carbon (AOC) and inert organic carbon (NOC) tended to increase with the prolongation of farming time, but there was a difference in the increase of AOC and NOC. The AOC Therefore, during the early stage of farming (0-5 years), the increase of AOC was higher than that of NOC, while the increase of NOC of cultivated land over 20 years was greater than that of AOC, and then reached The trend of AOC and NOC increase is close to (> 100 a), indicating that the accumulation of total organic carbon is the process of gradual increase of AOC and NOC and the accumulation of NOC. > 100 a. Due to different planting methods, the contents of TOC, AOC and NOC in the profile show: rape land> common corn land> corn seed> wheat land. The analysis found that in recent years, oases have changed the TOC, AOC and NOC in a large area in maize planting. Increasing the return of straw or livestock manure is an effective way to increase soil organic carbon.