Jie Luo, Lukas Beule, Guodong Shao, Dan Niu, Edzo Veldkamp, Marife D. Corre
{"title":"两种截然不同的农林系统下的土壤总 N2O 排放量和吸收量:河岸树木缓冲区与巷作树行","authors":"Jie Luo, Lukas Beule, Guodong Shao, Dan Niu, Edzo Veldkamp, Marife D. Corre","doi":"10.1007/s10533-024-01141-3","DOIUrl":null,"url":null,"abstract":"<div><p>In addition to the removal of excess mineral nitrogen (N) via root uptake, trees in agroforestry systems may mitigate negative effects of high N fertilization of adjacent crops by enhancing complete denitrification of excess mineral N aside from root uptake. Presently, little is known about the potential for NO<sub>3</sub><sup>−</sup> reduction through denitrification (conversion to greenhouse gas N<sub>2</sub>O and subsequently to non-reactive N<sub>2</sub>) in contrasting agroforestry systems: riparian tree buffer versus tree row of an upland alley-cropping system. Our study aimed to (1) quantify gross N<sub>2</sub>O emissions (both N<sub>2</sub>O + N<sub>2</sub> emissions) and gross N<sub>2</sub>O uptake (N<sub>2</sub>O reduction to N<sub>2</sub>), and (2) determine their controlling factors. We employed the <sup>15</sup>N<sub>2</sub>O pool dilution technique to quantify gross N<sub>2</sub>O fluxes from 0 to 5 cm (topsoil) and 40 to 60 cm (subsoil) depths with seasonal field measurements in 2019. The riparian tree buffer exhibited higher topsoil gross N<sub>2</sub>O emissions and uptake than the alley-cropping tree row (<i>P</i> < 0.03). Gross N<sub>2</sub>O emissions were regulated by N and carbon (C) availabilities and aeration status rather than denitrification gene abundance. Gross N<sub>2</sub>O uptake was directly linked to available C and <i>nirK</i> gene abundance. In the subsoil, gross N<sub>2</sub>O emission and uptake were low in both agroforestry systems, resulting from low mineral N contents possibly due to N uptake by deep tree roots. Nonetheless, the larger available C and soil moisture in the subsoil of riparian tree buffer than in alley-cropping tree row (<i>P</i> < 0.05) suggest its large potential for N<sub>2</sub>O uptake whenever NO<sub>3</sub><sup>−</sup> is transported to the subsoil.</p></div>","PeriodicalId":8901,"journal":{"name":"Biogeochemistry","volume":null,"pages":null},"PeriodicalIF":3.9000,"publicationDate":"2024-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10533-024-01141-3.pdf","citationCount":"0","resultStr":"{\"title\":\"Soil gross N2O emission and uptake under two contrasting agroforestry systems: riparian tree buffer versus alley-cropping tree row\",\"authors\":\"Jie Luo, Lukas Beule, Guodong Shao, Dan Niu, Edzo Veldkamp, Marife D. Corre\",\"doi\":\"10.1007/s10533-024-01141-3\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>In addition to the removal of excess mineral nitrogen (N) via root uptake, trees in agroforestry systems may mitigate negative effects of high N fertilization of adjacent crops by enhancing complete denitrification of excess mineral N aside from root uptake. Presently, little is known about the potential for NO<sub>3</sub><sup>−</sup> reduction through denitrification (conversion to greenhouse gas N<sub>2</sub>O and subsequently to non-reactive N<sub>2</sub>) in contrasting agroforestry systems: riparian tree buffer versus tree row of an upland alley-cropping system. Our study aimed to (1) quantify gross N<sub>2</sub>O emissions (both N<sub>2</sub>O + N<sub>2</sub> emissions) and gross N<sub>2</sub>O uptake (N<sub>2</sub>O reduction to N<sub>2</sub>), and (2) determine their controlling factors. We employed the <sup>15</sup>N<sub>2</sub>O pool dilution technique to quantify gross N<sub>2</sub>O fluxes from 0 to 5 cm (topsoil) and 40 to 60 cm (subsoil) depths with seasonal field measurements in 2019. The riparian tree buffer exhibited higher topsoil gross N<sub>2</sub>O emissions and uptake than the alley-cropping tree row (<i>P</i> < 0.03). Gross N<sub>2</sub>O emissions were regulated by N and carbon (C) availabilities and aeration status rather than denitrification gene abundance. Gross N<sub>2</sub>O uptake was directly linked to available C and <i>nirK</i> gene abundance. In the subsoil, gross N<sub>2</sub>O emission and uptake were low in both agroforestry systems, resulting from low mineral N contents possibly due to N uptake by deep tree roots. Nonetheless, the larger available C and soil moisture in the subsoil of riparian tree buffer than in alley-cropping tree row (<i>P</i> < 0.05) suggest its large potential for N<sub>2</sub>O uptake whenever NO<sub>3</sub><sup>−</sup> is transported to the subsoil.</p></div>\",\"PeriodicalId\":8901,\"journal\":{\"name\":\"Biogeochemistry\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":3.9000,\"publicationDate\":\"2024-05-16\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://link.springer.com/content/pdf/10.1007/s10533-024-01141-3.pdf\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Biogeochemistry\",\"FirstCategoryId\":\"93\",\"ListUrlMain\":\"https://link.springer.com/article/10.1007/s10533-024-01141-3\",\"RegionNum\":3,\"RegionCategory\":\"环境科学与生态学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"ENVIRONMENTAL SCIENCES\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Biogeochemistry","FirstCategoryId":"93","ListUrlMain":"https://link.springer.com/article/10.1007/s10533-024-01141-3","RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ENVIRONMENTAL SCIENCES","Score":null,"Total":0}
Soil gross N2O emission and uptake under two contrasting agroforestry systems: riparian tree buffer versus alley-cropping tree row
In addition to the removal of excess mineral nitrogen (N) via root uptake, trees in agroforestry systems may mitigate negative effects of high N fertilization of adjacent crops by enhancing complete denitrification of excess mineral N aside from root uptake. Presently, little is known about the potential for NO3− reduction through denitrification (conversion to greenhouse gas N2O and subsequently to non-reactive N2) in contrasting agroforestry systems: riparian tree buffer versus tree row of an upland alley-cropping system. Our study aimed to (1) quantify gross N2O emissions (both N2O + N2 emissions) and gross N2O uptake (N2O reduction to N2), and (2) determine their controlling factors. We employed the 15N2O pool dilution technique to quantify gross N2O fluxes from 0 to 5 cm (topsoil) and 40 to 60 cm (subsoil) depths with seasonal field measurements in 2019. The riparian tree buffer exhibited higher topsoil gross N2O emissions and uptake than the alley-cropping tree row (P < 0.03). Gross N2O emissions were regulated by N and carbon (C) availabilities and aeration status rather than denitrification gene abundance. Gross N2O uptake was directly linked to available C and nirK gene abundance. In the subsoil, gross N2O emission and uptake were low in both agroforestry systems, resulting from low mineral N contents possibly due to N uptake by deep tree roots. Nonetheless, the larger available C and soil moisture in the subsoil of riparian tree buffer than in alley-cropping tree row (P < 0.05) suggest its large potential for N2O uptake whenever NO3− is transported to the subsoil.
期刊介绍:
Biogeochemistry publishes original and synthetic papers dealing with biotic controls on the chemistry of the environment, or with the geochemical control of the structure and function of ecosystems. Cycles are considered, either of individual elements or of specific classes of natural or anthropogenic compounds in ecosystems. Particular emphasis is given to coupled interactions of element cycles. The journal spans from the molecular to global scales to elucidate the mechanisms driving patterns in biogeochemical cycles through space and time. Studies on both natural and artificial ecosystems are published when they contribute to a general understanding of biogeochemistry.