{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:19:33Z","timestamp":1760059173618,"version":"build-2065373602"},"reference-count":41,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2025,5,28]],"date-time":"2025-05-28T00:00:00Z","timestamp":1748390400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sustainability"],"abstract":"<jats:p>Pasture-based dairy systems are a cornerstone of agricultural practices in the Azores, contributing significantly to both the local economy and environmental sustainability. However, the environmental impact of these systems, particularly in terms of methane (CH4) emissions, remains a major challenge, especially given the need to balance productivity with ecological preservation. This study aimed to compare enteric methane emissions, floristic composition, productivity, and nutritional quality between conventional and organic pasture systems in the Azores. Data were collected from representative dairy farms over a 12-month period, with pasture samples analyzed monthly to assess floristic diversity, dry matter productivity, and nutritional quality (crude protein and digestibility). Methane emissions were estimated using the IPCC Tier 2 methodology, incorporating data on animal performance, diet composition, and energy intake to calculate CH4 emissions per cow per year. The results showed that organic pastures had greater floristic diversity (5.10 \u00b1 0.25 species\/m2) than conventional pastures (4.00 \u00b1 0.23 species\/m2). However, conventional systems exhibited higher dry matter productivity (22.85 g\/m2 vs. 15.35 g\/m2) and incorporated corn silage, which enhanced digestible energy and reduced methane emissions (81.33 kg CH4\/cow\/year) compared to organic systems (89.17 kg CH4\/cow\/year). Although organic pastures had higher crude protein content (20.65%), their lower digestibility contributed to higher methane emissions. This study underscores the trade-offs between environmental sustainability, pasture productivity, and methane mitigation in pasture-based dairy systems, highlighting the need for integrated management approaches that balance ecological and production goals.<\/jats:p>","DOI":"10.3390\/su17114944","type":"journal-article","created":{"date-parts":[[2025,5,28]],"date-time":"2025-05-28T03:52:08Z","timestamp":1748404328000},"page":"4944","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Insights into Enteric Methane Emissions in Conventional and Organic Dairy Grazing Systems in Island Regions"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9935-851X","authenticated-orcid":false,"given":"H\u00e9lder P. B.","family":"Nunes","sequence":"first","affiliation":[{"name":"IITAA\u2014Institute of Agricultural and Environmental Research and Technology, Universidade dos A\u00e7ores, Rua Capit\u00e3o d\u2019\u00c1vila, S\u00e3o Pedro, PT-9700-042 Angra do Hero\u00edsmo, Portugal"},{"name":"FCAA\u2014Faculty of Agrarian and Environmental Sciences, Faculdade de Ci\u00eancias Agr\u00e1rias e do Ambiente, Universidade dos A\u00e7ores, Rua Capit\u00e3o Jo\u00e3o D\u2019\u00c1vila, S\u00e3o Pedro, PT-9700-042 Angra do Hero\u00edsmo, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6655-8109","authenticated-orcid":false,"given":"Cristiana","family":"Maduro Dias","sequence":"additional","affiliation":[{"name":"IITAA\u2014Institute of Agricultural and Environmental Research and Technology, Universidade dos A\u00e7ores, Rua Capit\u00e3o d\u2019\u00c1vila, S\u00e3o Pedro, PT-9700-042 Angra do Hero\u00edsmo, Portugal"},{"name":"FCAA\u2014Faculty of Agrarian and Environmental Sciences, Faculdade de Ci\u00eancias Agr\u00e1rias e do Ambiente, Universidade dos A\u00e7ores, Rua Capit\u00e3o Jo\u00e3o D\u2019\u00c1vila, S\u00e3o Pedro, PT-9700-042 Angra do Hero\u00edsmo, Portugal"}]},{"given":"Adriana","family":"Abreu","sequence":"additional","affiliation":[{"name":"FCAA\u2014Faculty of Agrarian and Environmental Sciences, Faculdade de Ci\u00eancias Agr\u00e1rias e do Ambiente, Universidade dos A\u00e7ores, Rua Capit\u00e3o Jo\u00e3o D\u2019\u00c1vila, S\u00e3o Pedro, PT-9700-042 Angra do Hero\u00edsmo, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8481-791X","authenticated-orcid":false,"given":"Alfredo","family":"Borba","sequence":"additional","affiliation":[{"name":"IITAA\u2014Institute of Agricultural and Environmental Research and Technology, Universidade dos A\u00e7ores, Rua Capit\u00e3o d\u2019\u00c1vila, S\u00e3o Pedro, PT-9700-042 Angra do Hero\u00edsmo, Portugal"},{"name":"FCAA\u2014Faculty of Agrarian and Environmental Sciences, Faculdade de Ci\u00eancias Agr\u00e1rias e do Ambiente, Universidade dos A\u00e7ores, Rua Capit\u00e3o Jo\u00e3o D\u2019\u00c1vila, S\u00e3o Pedro, PT-9700-042 Angra do Hero\u00edsmo, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0691-6725","authenticated-orcid":false,"given":"Catarina D.","family":"Melo","sequence":"additional","affiliation":[{"name":"FCAA\u2014Faculty of Agrarian and Environmental Sciences, Faculdade de Ci\u00eancias Agr\u00e1rias e do Ambiente, Universidade dos A\u00e7ores, Rua Capit\u00e3o Jo\u00e3o D\u2019\u00c1vila, S\u00e3o Pedro, PT-9700-042 Angra do Hero\u00edsmo, Portugal"},{"name":"CE3C\u2014Centre for Ecology, Evolution and Environmental Changes, Azorean Biodiversity Group, Faculdade de Ci\u00eancias Agr\u00e1rias e do Ambiente, Universidade dos A\u00e7ores, Rua Capit\u00e3o Jo\u00e3o D\u2019\u00c1vila, S\u00e3o Pedro, PT-9700-042 Angra do Hero\u00edsmo, Portugal"},{"name":"CFE\u2014Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, PT-3001-401 Coimbra, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,5,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Nunes, H.P.B., Dias, C.S.A.M.M., Vouzela, C.M., and Borba, A.E.S. 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