S. Carolina Córdova, Alexandra N. Kravchenko, Jessica R. Miesel, G. Philip Robertson
{"title":"Soil carbon change in intensive agriculture after 25 years of conservation management","authors":"S. Carolina Córdova, Alexandra N. Kravchenko, Jessica R. Miesel, G. Philip Robertson","doi":"10.1016/j.geoderma.2024.117133","DOIUrl":null,"url":null,"abstract":"Changes in soil organic carbon (SOC) and nitrogen (SON) are strongly affected by land management but few long-term comparative studies have surveyed changes throughout the whole soil profile. We quantified 25-year SOC and SON changes to 1 m in 10 replicate ecosystems at an Upper Midwest, USA site. We compared four annual cropping systems in maize (<ce:italic>Zea mays</ce:italic>)-soybean (<ce:italic>Glycine</ce:italic> max)-winter wheat (<ce:italic>Triticum aestivum</ce:italic>) rotations, each managed differently (Conventional, No-till, Reduced input, and Biologically based); in three managed perennial systems (hybrid Poplar (<ce:italic>Populus</ce:italic> × <ce:italic>euramericana</ce:italic>), Alfalfa (<ce:italic>Medicago sativa</ce:italic>), and Conifer (<ce:italic>Pinus</ce:italic> spp.); and in three successional systems (Early, Mid- and Late succession undergoing a gradual change in species composition and structure over time). Both Reduced input and Biologically based systems included winter cover crops. Neither SOC nor SON changed significantly in the Conventional or Late successional systems over 25 years. All other systems gained SOC and SON to different degrees. SOC accrual was fastest in the Early successional system (0.8 ± 0.1 Mg C ha<ce:sup loc=\"post\">−1</ce:sup> y<ce:sup loc=\"post\">−1</ce:sup>) followed by Alfalfa and Conifer (avg. 0.7 ± 0.1 Mg C ha<ce:sup loc=\"post\">−1</ce:sup> y<ce:sup loc=\"post\">−1</ce:sup>), Poplar, Reduced input, and Biologically based systems (avg. 0.4 ± 0.1 Mg C ha<ce:sup loc=\"post\">−1</ce:sup> y<ce:sup loc=\"post\">−1</ce:sup>), and Mid-successional and No-till systems (0.3 and 0.2 Mg C ha<ce:sup loc=\"post\">−1</ce:sup> y<ce:sup loc=\"post\">−1</ce:sup>, respectively). Over the most recent 12 years, rates of SOC accrual slowed in all systems except Reduced input and Mid-successional. There was no evidence of SOC loss at depth in any system, including No-till. Rates of SON accrual ranged from 64.7 to 0.8 kg N ha<ce:sup loc=\"post\">−1</ce:sup> y<ce:sup loc=\"post\">−1</ce:sup> in the order Alfalfa ≥ Early successional > Reduced input and Biologically based ≥ Poplar > No-till and Conifer > Mid-successional systems. Pyrogenic C levels in the Conventional, Early, and Late successional systems were similar despite 17 years of annual burning in the Early successional system (∼ 15 % of SOC to 50 cm, on average, and ∼40 % of SOC from 50 to 100 cm). Results underscore the importance of cover crops, perennial crops, and no-till options for sequestering whole profile C in intensively managed croplands.","PeriodicalId":12511,"journal":{"name":"Geoderma","volume":"32 1","pages":""},"PeriodicalIF":5.6000,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Geoderma","FirstCategoryId":"97","ListUrlMain":"https://doi.org/10.1016/j.geoderma.2024.117133","RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"SOIL SCIENCE","Score":null,"Total":0}
引用次数: 0
Abstract
Changes in soil organic carbon (SOC) and nitrogen (SON) are strongly affected by land management but few long-term comparative studies have surveyed changes throughout the whole soil profile. We quantified 25-year SOC and SON changes to 1 m in 10 replicate ecosystems at an Upper Midwest, USA site. We compared four annual cropping systems in maize (Zea mays)-soybean (Glycine max)-winter wheat (Triticum aestivum) rotations, each managed differently (Conventional, No-till, Reduced input, and Biologically based); in three managed perennial systems (hybrid Poplar (Populus × euramericana), Alfalfa (Medicago sativa), and Conifer (Pinus spp.); and in three successional systems (Early, Mid- and Late succession undergoing a gradual change in species composition and structure over time). Both Reduced input and Biologically based systems included winter cover crops. Neither SOC nor SON changed significantly in the Conventional or Late successional systems over 25 years. All other systems gained SOC and SON to different degrees. SOC accrual was fastest in the Early successional system (0.8 ± 0.1 Mg C ha−1 y−1) followed by Alfalfa and Conifer (avg. 0.7 ± 0.1 Mg C ha−1 y−1), Poplar, Reduced input, and Biologically based systems (avg. 0.4 ± 0.1 Mg C ha−1 y−1), and Mid-successional and No-till systems (0.3 and 0.2 Mg C ha−1 y−1, respectively). Over the most recent 12 years, rates of SOC accrual slowed in all systems except Reduced input and Mid-successional. There was no evidence of SOC loss at depth in any system, including No-till. Rates of SON accrual ranged from 64.7 to 0.8 kg N ha−1 y−1 in the order Alfalfa ≥ Early successional > Reduced input and Biologically based ≥ Poplar > No-till and Conifer > Mid-successional systems. Pyrogenic C levels in the Conventional, Early, and Late successional systems were similar despite 17 years of annual burning in the Early successional system (∼ 15 % of SOC to 50 cm, on average, and ∼40 % of SOC from 50 to 100 cm). Results underscore the importance of cover crops, perennial crops, and no-till options for sequestering whole profile C in intensively managed croplands.
期刊介绍:
Geoderma - the global journal of soil science - welcomes authors, readers and soil research from all parts of the world, encourages worldwide soil studies, and embraces all aspects of soil science and its associated pedagogy. The journal particularly welcomes interdisciplinary work focusing on dynamic soil processes and functions across space and time.