摘要
横坡垄作对坡耕地土壤有机碳(soil organic carbon,SOC)流失有一定的阻控作用,但黑土区特有长而缓的地形与横垄对坡耕地SOC空间分异会产生交互作用,而这种交互作用引发的SOC流失风险没引起足够的重视。该研究以典型黑土区黑龙江省黑河市北安分局红星农场为研究区域,2022年在横坡垄作与顺坡水线方向上共布设25个采样点,采用地理探测器模型、单因素方差分析(one-way ANOVA)和Pearson相关性分析,探讨土壤有机碳的空间分异及其交互作用。结果表明,横坡垄作方向上垄沟土壤有机碳含量从坡顶到水线呈现逐渐增大的变化趋势;在垄台从坡顶到水线呈现先增大后减小的变化趋势。顺坡水线方向,土壤有机碳含量在垄沟呈现从上坡到下坡增大的变化趋势;在垄台呈现先增大后减小的变化趋势。由于断垄产生水线,顺坡土壤有机碳含量上坡与下坡仍有显著差异(P<0.05)。Pearson相关性分析表明,有机碳与可蚀性K因子呈显著负相关(垄沟和垄台相关系数分别为–0.228和–0.238,P<0.05),与碳循环相关的β-葡萄糖苷酶和微生物生物量碳在垄沟呈极显著正相关(相关系数为0.398和0.676,P<0.01)。地理探测器分析表明,顺坡水线对土壤有机碳空间分异的影响最大,其对垄沟和垄台SOC的解释力分别达到61%和52%以上;顺坡水线与其他因子的交互作用共同增强了对土壤有机碳的解释力,尤其是顺坡水线与高程的交互作用最为明显。黑土区坡耕地土壤有机碳空间分异主要受顺坡水线与高程的交互作用,横坡垄作虽然能够拦截径流,但由于长缓坡地形影响产生的断垄会加剧土壤侵蚀诱发的有机碳流失。因此,黑土坡耕地治理需要同时考虑横垄与地形的共同影响,从而实现防蚀的优化效果。
The contour ridge tillage had a certain effect on reducing soil organic carbon(SOC)loss in sloping cropland,but the unique long and slow topography would interact with contour ridge cropping on the spatial differentiation of SOC in sloping cropland of the black area.However,the risk of SOC loss caused by this interaction has not attracted enough attention yet.In this study,Hongxing Farm of Beian Branch,Heihe City,Heilongjiang Province,a typical black soil area,was taken as the study area,and the two directions of the contour ridge cropping and longitudinal waterline direction were divided according to the study purpose under the contour ridge cropping measure,and a total of 75 sample sizes were taken in the two directions.The geographic detector model as well as one-way ANOVA and Pearson's correlation analysis were conducted to explore the spatial differentiation of SOC and its interactive effects.In the contour ridge tillage direction,SOC content showed a trend of gradual increase from the top position of the slope to the waterline in the ridge furrow;and it showed a trend of increase and then decrease from the top position of the slope to the waterline in the ridge platform.Along the longitudinal waterline direction,the SOC content showed a trend of increasing from lower to upper position in the ridges,and it showed a trend of increasing and then decreasing in the ridge platform.Soil organic carbon content was significantly greater in ridges than in furrows(P<0.05).The soil organic carbon content of the upper was still significantly different from the lower due to the waterline created by the broken ridge(P<0.05).Spatial differentiation of soil organic carbon resulted in greater spatial variability of SOC along the direction of contour ridge cropping and less spatial variability along the direction of the longitudinal waterline.Pearson's correlation analysis showed that organic carbon was significantly negatively correlated with the erodibility factor(correlation coefficient of-0.228 and-0.238,P<0.05 for furrow and platform,respectively),and thatβ-glucosidase(BG)and microbial biomass carbon(MBC),which are related to carbon cycling,were highly significantly positively correlated with the erodibility factor in furrow(correlation coefficient of 0.398 and 0.676,P<0.01).Geographic detector analysis showed that,among the single factors,the longitudinal waterline had the greatest effect on soil organic carbon differentiation,and its explanatory rate reached more than 61%and 52%for ridges and ridgetops,respectively;among the two factors,the interaction between longitudinal waterline and other factors had the greatest effect,and all of them strengthened the explanatory power of soil organic carbon,especially the interaction between longitudinal waterline and topography was the most obvious,and the explanatory rate in ridges and ridgetops both reached more than 90%.The spatial differentiation of SOC in sloping cropland in the black soil area was mainly affected by the interaction between the longitudinal waterline and topography on the downslope.Although the contour ridge tillage was able to intercept runoff,the broken ridges generated by the influence of the topography on the long and gentle slopes will exacerbate the loss of SOC induced by soil erosion.Therefore,it is suggested to consider the joint influence of contour ridges and topography at the same time in the management of black soil slope cropland,and to pay enough attention to the potential risk of contour ridges,so as to achieve the optimized effect for erosion prevention.
作者
李雪亮
张晴雯
李孟妮
石玉龙
于博威
荆雪锴
蒋嫄可
刘国成
LI Xueliang;ZHANG Qingwen;LI Mengni;SHI Yulong;YU Bowei;JING Xuekai;JIANG Yuanke;LIU Guocheng(College of Resources and Environment Sciences,Qingdao Agricultural University,Qingdao 266109,China;Institute of Agricultural Environment and Sustainable Development in Agriculture,Chinese Academy of Agricultural Sciences,Beijing 100081,China)
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2024年第3期103-113,共11页
Transactions of the Chinese Society of Agricultural Engineering
基金
国家自然科学基金项目(41977072)
中国农业科学院科技创新工程项目(CAAS-ZDRW-202202,CAAS-CSAL-202302)。
关键词
土壤
侵蚀
有机碳
坡耕地
横坡垄作
交互作用
soils
erosion
organic carbon
slope cropland
contour ridge tillage
interaction