研究报告
胥佳忆,李先德,刘吉龙,黑杰,王亚非,尹晓雷,阳祥,张永勋,王维奇.农业土地利用转变对土壤团聚体组成及碳、氮含量的影响[J].环境科学学报,2022,42(8):438-448
农业土地利用转变对土壤团聚体组成及碳、氮含量的影响
- Effects of the change of agricultural soil utilization pattern on soil aggregate composition and carbon, nitrogen content
- 基金项目:国家自然科学基金(No.41571287);“安徽铜陵姜-稻轮作系统”申报全球重要农业文化遗产项目
- 胥佳忆
- 福建师范大学地理科学学院,福州 350007
- 李先德
- 中国农业科学院农业经济与发展研究所,北京 100081
- 刘吉龙
- 中国农业科学院农业经济与发展研究所,北京 100081
- 王亚非
- 福建师范大学地理科学学院,福州 350007
- 尹晓雷
- 福建师范大学地理科学学院,福州 350007
- 张永勋
- 中国农业科学院农业经济与发展研究所,北京 100081
- 王维奇
- 福建师范大学地理科学学院,福州 350007;福建师范大学湿润亚热带生态-地理过程教育部重点实验室,福州 350007
- 摘要:为探究农业土地利用转变对土壤团聚体组成、稳定性及有机碳(SOC)、全氮(TN)含量变化的影响,选取玉米地、玉米地转变为姜地、稻田和稻田转变为姜地4种农业土地利用类型为研究对象,对土壤水稳性团聚体的组成、稳定性及SOC、TN含量进行测定与分析.结果表明: ①玉米地转变为姜地后,>0.25 mm粒级的大团聚体减少21.48%(p<0.01),>0.25 mm稳定性团聚体的含量(DR0.25)显著降低53.39%;稻田转变为姜地后,大团聚体差异不显著,<0.053 mm粒级的粉黏团聚体增加8.93%(p<0.01);冗余分析和相关分析表明,土壤含水量是团聚体组成和 稳定性的重要影响因素;②玉米地转变为姜地后,0.25~1 mm粒级团聚体中SOC、TN含量分别减少52.68%、50.98%,粉黏团聚体(<0.053 mm)中SOC和TN含量增加约2倍(p<0.01);稻田转变为姜地后,>0.25 mm的大团聚体和0.053~0.25 mm的微团聚体中的SOC、TN含量均减少(p<0.05),其中,大团聚体碳氮比与团聚体组成和稳定性存在相关关系(p<0.05);③所有处理均为大团聚体SOC、TN贡献率最高,转变后的姜地较玉米地、稻田的土壤粉黏团聚体的SOC、TN贡献率显著增加,尤其是较玉米地的粉黏团聚体SOC、TN贡献率增加3倍(p<0.01);④平均质量 直径(MWD)和几何平均直径(GMD)与大团聚体的SOC、TN含量呈显著正相关(p<0.05),分形维数(D)与MWD及1~2 mm粒级大团聚体的SOC、TN含量呈显著负相关(p<0.01),DR0.25与大团聚体的SOC、TN含量呈显著正相关(p<0.01).总体上,玉米地和稻田两种用地转变为姜地后,土壤团聚体的组成发生较大变化,团聚体稳定性变化虽不显著,但大团聚体中SOC、TN含量降低,粉黏团聚体中SOC、TN含量增加.本研究的开展对农田科学管理和可持续生产具有重要的指导意义.
- Abstract:In order to explore the effects of the change of agricultural soil utilization pattern on the composition and stability characteristics of farmland soil aggregates and the changes of soil organic carbon(SOC) and total nitrogen(TN), we took four farmland types, such as corn field, corn changing into ginger field, rice field and rice field changing into ginger field as the research objects, and the composition, stability, SOC and TN content of soil water stable aggregates were measured and analyzed. The results showed that: ① Large aggregates with particle size > 0.25 mm were reduced by 21.48% compared with corn field (p<0.01), and the DR0.25 was significantly reduced by 53.39%, and the large aggregates were not significantly changed after rice field changing to ginger field, however, silt and clay aggregates < 0.053 mm were increased by 8.93% (p<0.01). Soil water content was an important factor influencing the composition and stability of aggregates by RDA and correlation analysis. ② SOC and TN contents were decreased by 52.68%, 50.98% in 0.25~1 mm aggregates of ginger field comparison with the corn field, however, SOC and TN contents were increased by two times in < 0.053 mm aggregates(p<0.01). Compared with rice field, SOC and TN contents of large aggregates and microaggregates were decreased in ginger field (p<0.05). Carbon to nitrogen ratio of large aggregates was correlated with the composition and stability of the aggregates.③ In all treatments, the SOC and TN contribution rates of large aggregates were the highest, and the contribution rates of SOC and TN of silt and clay aggregates were increased in ginger field comparison with those of corn and rice fields, especially SOC and TN contribution rates of the silt and clay aggregates were increased by 3 times after corn field alternation to ginger field (p<0.01). ④The stability parameters, for example MWD and GMD of aggregates were significantly and positively correlated with the SOC and TN contents of large aggregates(p<0.05). D was significantly and negatively correlated with MWD, SOC and TN contents of 1~2 mm aggregates(p<0.01). DR0.25 was significantly and positively correlated with the SOC and TN content of large aggregates (p<0.01). In general, the composition of soil aggregates changes greatly. the stability of aggregates did not change, moreover, the contents of SOC and TN contents were decreased of large aggregates, and the content of SOC and TN in in silt and clay aggregates were increased after corn fields and rice fields are converted to ginger fields. The research will be of great significance to scientific management and and sustainable production in farmlands.