{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T05:06:59Z","timestamp":1790140019011,"version":"4.0.1"},"reference-count":31,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T00:00:00Z","timestamp":1790121600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Plant Sci."],"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>\n                      Farmland shelterbelts are critical for agricultural production in arid and semiarid regions, but they may compete with crops for limited soil water. This study aimed to quantify seasonal water-source use, soil moisture dynamics, and fine-root distribution in a\n                      <jats:italic>Populus simonii<\/jats:italic>\n                      \u2013maize shelterbelt system.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      The study was conducted in Zhangbei County, northwestern Hebei Province, China. Three land-use conditions were compared: a pure\n                      <jats:italic>P. simonii<\/jats:italic>\n                      shelterbelt (P), a\n                      <jats:italic>P. simonii<\/jats:italic>\n                      \u2013maize intercropping system (PC), and a maize monoculture reference (C). Synchronous sampling was conducted in May, July, August, and October 2023. Stable hydrogen and oxygen isotope ratios of soil water, groundwater, and plant xylem water were measured. The MixSIAR Bayesian mixing model was used to estimate water-source contributions. Fine-root length density was measured to 160 cm depth and at four horizontal distances from tree trunks. Schoener\u2019s proportional similarity index, Pianka\u2019s niche-overlap index, and Levins\u2019 niche-breadth index were calculated.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      <jats:italic>P. simonii<\/jats:italic>\n                      relied strongly on deep soil water and a groundwater-like endmember, with a combined contribution exceeding 55% during the dry season. Maize relied more on shallow soil water, with &amp;gt;60% of its water uptake from the 0\u201340 cm layer during the rainy season; during the dry season, its estimated contribution from 40\u2013100 cm increased. Water-source overlap was higher in the dry season than in the rainy season. The strongest fine-root co-occurrence occurred in the 40\u201380 cm soil layer within 0\u2013100 cm of the tree trunk.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Discussion<\/jats:title>\n                    <jats:p>\n                      <jats:italic>P. simonii<\/jats:italic>\n                      exhibited a broader and more stable water-source niche than maize. Maize showed a larger seasonal shift in water uptake, especially under intercropping, suggesting an asymmetric water-use response. These results identify the specific soil layers and periods where tree\u2013crop water interactions are likely to occur. However, because the study was conducted in a single year and at one site, the findings should be treated as testable hypotheses for future multi-year, replicated irrigation and spacing experiments.\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fpls.2026.1968926","type":"journal-article","created":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T04:43:40Z","timestamp":1790138620000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Seasonal shifts in water-source partitioning and fine-root overlap in a Populus simonii\u2013maize shelterbelt system"],"prefix":"10.3389","volume":"17","author":[{"given":"Jianuo","family":"Zhang","sequence":"first","affiliation":[{"name":"North China University of Water Resources and Electric Power","place":["Zhengzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zerui","family":"Tan","sequence":"additional","affiliation":[{"name":"Co\u2010Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University","place":["Nanjing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Han","family":"Yan","sequence":"additional","affiliation":[{"name":"Key Laboratory of Soil and Water Conservation and Desertification Combating of Ministry of Education, Beijing Forestry University","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fengbin","family":"Sun","sequence":"additional","affiliation":[{"name":"Weather Modification Centre, China Meteorological Administration","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,9,23]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","DOI":"10.3390\/agriculture15192004","article-title":"Enhancing agroecological resilience in arid regions: A review of shelterbelt structure and function","volume":"15","author":"Aili","year":"2025","journal-title":"Agriculture"},{"key":"B2","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0312876","article-title":"Synergistic windbreak efficiency of desert vegetation and oasis shelter forests","volume":"19","author":"Aili","year":"2024","journal-title":"PloS One"},{"key":"B3","doi-asserted-by":"publisher","DOI":"10.1016\/j.agwat.2023.108206","article-title":"Water competition among the coexisting Platycladus orientalis, Prunus davidiana and Medicago sativa in a semi-arid agroforestry system","volume":"279","author":"Chen","year":"2023","journal-title":"Agric. Water Manage."},{"key":"B4","doi-asserted-by":"publisher","first-page":"907","DOI":"10.1007\/s10457-020-00527-0","article-title":"Using isotopic labeling to investigate root water uptake in an alley cropping system within Taklimakan Desert Oasis, China","volume":"95","author":"Guo","year":"2021","journal-title":"Agrofor. Syst."},{"key":"B5","doi-asserted-by":"publisher","first-page":"588","DOI":"10.1016\/j.ijsrc.2025.04.004","article-title":"Effects of different vegetation litter cover on hydrodynamic characteristics of soil runoff-sediment yield in Taiyi Mountain area of northern China","volume":"40","author":"He","year":"2025","journal-title":"Int. J. Sediment Res."},{"key":"B6","doi-asserted-by":"publisher","DOI":"10.3390\/w16020198","article-title":"Comparison of water utilization patterns of sunflowers and maize at different fertility stages along the Yellow River","volume":"16","author":"He","year":"2024","journal-title":"Water"},{"key":"B7","doi-asserted-by":"publisher","DOI":"10.3390\/f14102087","article-title":"Tree ring width responses of Pinus densiflora and Robinia pseudoacacia to climate variation in the Mount Tai area of Northern China","volume":"14","author":"He","year":"2023","journal-title":"Forests"},{"key":"B8","doi-asserted-by":"publisher","first-page":"3963","DOI":"10.5194\/hess-28-3963-2024","article-title":"Hydrological and pedological effects of combining Italian alder and blackberries in an agroforestry windbreak system in South Africa","volume":"28","author":"Hoffmeister","year":"2024","journal-title":"Hydrol. Earth Syst. Sci."},{"key":"B9","doi-asserted-by":"publisher","DOI":"10.1016\/j.agrformet.2021.108620","article-title":"Dynamics of interspecific water relationship in vertical and horizontal dimensions under a dryland apple-Brassica intercropping system: Quantifying by experiments and the 3D Hi-sAFe model","volume":"310","author":"Huo","year":"2021","journal-title":"Agric. For. Meteorol."},{"key":"B10","doi-asserted-by":"publisher","DOI":"10.3389\/fsufs.2021.606631","article-title":"Crop yields in European agroforestry systems: A meta-analysis","volume":"5","author":"Ivezic","year":"2021","journal-title":"Front. Sustain. Food. Syst."},{"key":"B11","doi-asserted-by":"publisher","DOI":"10.1002\/eco.70060","article-title":"Increased groundwater dependence of riparian vegetation in response to drought","volume":"18","author":"Kui","year":"2025","journal-title":"Ecohydrology"},{"key":"B12","doi-asserted-by":"publisher","DOI":"10.1111\/1365-2745.70302","article-title":"Dominant and subdominant rooting niches","volume":"114","author":"Kulmatiski","year":"2026","journal-title":"J. Ecol."},{"key":"B13","doi-asserted-by":"publisher","DOI":"10.1093\/plphys\/kiaf432","article-title":"Integrating 3D imaging, GWAS, and single-cell transcriptome approaches to elucidate root system architecture in Populus","volume":"199","author":"Li","year":"2025","journal-title":"Plant Physiol."},{"key":"B14","doi-asserted-by":"publisher","DOI":"10.1016\/j.agee.2020.106832","article-title":"Optimizing the quantity and spatial patterns of farmland shelter forests increases cotton productivity in arid lands","volume":"292","author":"Li","year":"2020","journal-title":"Agric. Ecosyst. Environ."},{"key":"B15","doi-asserted-by":"publisher","DOI":"10.1016\/j.jhydrol.2022.128201","article-title":"Deep soil water deficit causes Populus simonii Carr degradation in the three north shelterbelt region of China","volume":"612","author":"Liang","year":"2022","journal-title":"J. Hydrol."},{"key":"B16","doi-asserted-by":"publisher","DOI":"10.1016\/j.agwat.2020.106138","article-title":"Water uptake and WUE of Apple tree-Corn Agroforestry in the Loess hilly region of China","volume":"234","author":"Liu","year":"2020","journal-title":"Agric. Water Manage."},{"key":"B17","doi-asserted-by":"publisher","DOI":"10.1016\/j.foreco.2026.123842","article-title":"Root architecture links water source plasticity and growth stability in subtropical trees under seasonal drought","volume":"615","author":"Liu","year":"2026","journal-title":"For. Ecol. Manage."},{"key":"B18","doi-asserted-by":"publisher","first-page":"109687","DOI":"10.1016\/j.catena.2025.109687.","article-title":"Shallow resource foraging and deep-water shift: plant-soil feedbacks sustain transient coexistence during Phyllostachys edulis invasion","volume":"262","author":"Liu","year":"2026","journal-title":"Catena"},{"key":"B19","doi-asserted-by":"publisher","DOI":"10.3389\/fpls.2022.894172","article-title":"Application of UAV remote sensing in monitoring water use efficiency and biomass of cotton plants adjacent to shelterbelt","volume":"13","author":"Ma","year":"2022","journal-title":"Front. Plant Sci."},{"key":"B20","doi-asserted-by":"publisher","first-page":"6","DOI":"10.1080\/00049158.2022.2027648","article-title":"Maximising the benefits of trees on farms in Tasmania - a desktop review of investment opportunities to improve farm enterprise productivity, profitability and sustainability","volume":"85","author":"Monckton","year":"2022","journal-title":"Aust. For."},{"key":"B21","doi-asserted-by":"publisher","first-page":"1151","DOI":"10.1111\/1365-2745.14088","article-title":"Crops grown in mixtures show niche partitioning in spatial water uptake","volume":"111","author":"Schmutz","year":"2023","journal-title":"J. Ecol."},{"key":"B22","doi-asserted-by":"publisher","first-page":"73","DOI":"10.1007\/s13593-023-00927-3","article-title":"Are agroforestry systems more productive than monocultures in Mediterranean countries? A meta-analysis","volume":"43","author":"Scordia","year":"2023","journal-title":"Agron. Sustain. Dev."},{"key":"B23","doi-asserted-by":"publisher","DOI":"10.1016\/j.agwat.2025.109747","article-title":"Stable water isotope analysis of plant-soil interspecific interactions in wheat-maize intercropping","volume":"319","author":"Shi","year":"2025","journal-title":"Agric. Water Manage."},{"key":"B24","doi-asserted-by":"publisher","first-page":"250","DOI":"10.1038\/s41561-023-01125-2","article-title":"Global patterns of water storage in the rooting zones of vegetation","volume":"16","author":"Stocker","year":"2023","journal-title":"Nat. Geosci."},{"key":"B25","doi-asserted-by":"publisher","first-page":"209","DOI":"10.1111\/jac.12553","article-title":"Competition, stress and benefits: Trees and crops in the transition zone of a temperate short rotation alley cropping agroforestry system","volume":"208","author":"Swieter","year":"2022","journal-title":"J. Agron. Crop Sci."},{"key":"B26","doi-asserted-by":"publisher","DOI":"10.1038\/srep19502","article-title":"Below-ground interspecific competition for water in a rubber agroforestry system may enhance water utilization in plants","volume":"6","author":"Wu","year":"2016","journal-title":"Sci. Rep."},{"key":"B27","doi-asserted-by":"publisher","first-page":"30","DOI":"10.1016\/j.jaridenv.2016.03.004","article-title":"Fine root distributions of shelterbelt trees and their water sources in an oasis of arid northwestern China","volume":"130","author":"Xiao","year":"2016","journal-title":"J. Arid. Environ."},{"key":"B28","doi-asserted-by":"publisher","DOI":"10.1128\/spectrum.03683-23","article-title":"A comparative analysis of soil physicochemical properties and microbial community structure among four shelterbelt species in the northeast China plain","volume":"12","author":"Yang","year":"2024","journal-title":"Microbiol. Spectr."},{"key":"B29","doi-asserted-by":"publisher","DOI":"10.3389\/fpls.2025.1607207","article-title":"Opinionated views on biophysical and social constraints on agroforestry system","volume":"16","author":"Zha","year":"2025","journal-title":"Front. Plant Sci."},{"key":"B30","doi-asserted-by":"publisher","DOI":"10.1016\/j.jhydrol.2024.130677","article-title":"Dynamic hydrological niche segregation: How plants compete for water in a semi-arid ecosystem","volume":"630","author":"Zhao","year":"2024","journal-title":"J. Hydrol."},{"key":"B31","doi-asserted-by":"publisher","first-page":"499","DOI":"10.1007\/s11104-023-06349-0","article-title":"Matching root water uptake patterns to fine root and soil water distributions","volume":"495","author":"Zhu","year":"2024","journal-title":"Plant Soil"}],"container-title":["Frontiers in Plant Science"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fpls.2026.1968926\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T04:43:46Z","timestamp":1790138626000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fpls.2026.1968926\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,9,23]]},"references-count":31,"alternative-id":["10.3389\/fpls.2026.1968926"],"URL":"https:\/\/doi.org\/10.3389\/fpls.2026.1968926","relation":{},"ISSN":["1664-462X"],"issn-type":[{"value":"1664-462X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,9,23]]},"article-number":"1968926"}}