{"id":31646,"date":"2025-07-07T15:17:55","date_gmt":"2025-07-07T13:17:55","guid":{"rendered":"http:\/\/&amp;p=26335"},"modified":"2025-07-07T15:17:55","modified_gmt":"2025-07-07T13:17:55","slug":"desertification-pathways-induced-by-rapid-vegetation-transformations-from-shrub-encroachment-to-exotic-grass-invasions-in-north-american-deserts","status":"publish","type":"tribe_events","link":"https:\/\/www.dica.polimi.it\/it\/evento\/desertification-pathways-induced-by-rapid-vegetation-transformations-from-shrub-encroachment-to-exotic-grass-invasions-in-north-american-deserts\/","title":{"rendered":"Desertification pathways induced by rapid vegetation transformations: from shrub encroachment to exotic grass invasions in North American deserts"},"content":{"rendered":"<p><strong>Mercoled\u00ec 9 Luglio <\/strong>si terr\u00e0 un seminario presso l\u2019aula Castigliano (Edificio 5) dalle ore 10:00 dal titolo <strong>\u201cDesertification pathways induced by rapid vegetation transformations: from shrub encroachment to exotic grass invasions in North American deserts<\/strong><strong>\u201d<\/strong>.<\/p>\n<p>Il seminario sar\u00e0 tenuto dal <b data-ogsc=\"\" data-olk-copy-source=\"MessageBody\">Dr. Sijith Ravi,\u00a0<\/b><i data-ogsc=\"\">Department of Earth and Environmental Science, Temple University, Philadelphia, PA, USA.<\/i><\/p>\n<div class=\"x_elementToProof\" data-ogsc=\"rgb(0, 0, 0)\" data-ogsb=\"rgb(255, 255, 255)\"><b data-ogsc=\"\" data-olk-copy-source=\"MessageBody\">Abstract<\/b><\/div>\n<div data-ogsc=\"rgb(0, 0, 0)\" data-ogsb=\"rgb(255, 255, 255)\"><\/div>\n<div class=\"x_elementToProof\" data-ogsc=\"rgb(0, 0, 0)\" data-ogsb=\"rgb(255, 255, 255)\">Vegetation patterns and transitions in drylands, such as shrub encroachment and grass invasions, are often sustained by positive feedbacks between ecosystem states and environmental conditions (e.g., sediment\u2013vegetation interactions) or disturbances (e.g., fire, grazing), operating across scales from patches to landscapes. Drawing on a decade of research at shrub\u2013grass ecotones in North American deserts, we identify internal feedback mechanisms\u2014such as those involving soil moisture, microclimate, and nutrient dynamics\u2014that reinforce shrub-dominated states, and demonstrate how these are altered by prescribed fire and grazing management. We hypothesize that similar feedbacks underlie transitions from native shrublands to invasive grasslands in other desert systems, such as the Sonoran Desert, although the ecological consequences may differ. Our findings suggest that both spatial heterogeneity, associated with shrub encroachment, and spatial homogenization, associated with grass invasions, can drive land degradation, depending on plant functional traits and feedback dynamics. These processes underscore the critical role of vegetation\u2013sediment interactions in shaping pattern formation, state transitions, desertification, and the long-term stability of arid landscapes.<\/div>\n<div data-ogsc=\"rgb(0, 0, 0)\" data-ogsb=\"rgb(255, 255, 255)\"><\/div>\n<div data-ogsc=\"rgb(0, 0, 0)\" data-ogsb=\"rgb(255, 255, 255)\">&#8212;<\/div>\n<div data-ogsc=\"rgb(0, 0, 0)\" data-ogsb=\"rgb(255, 255, 255)\"><\/div>\n<div class=\"x_elementToProof\" data-ogsc=\"rgb(0, 0, 0)\" data-ogsb=\"rgb(255, 255, 255)\"><span data-ogsc=\"\" data-ogsb=\"rgb(255, 255, 255)\"><b data-ogsc=\"\">Speaker&#8217;s bio<\/b><\/span><\/div>\n<div data-ogsc=\"rgb(0, 0, 0)\" data-ogsb=\"rgb(255, 255, 255)\"><\/div>\n<div class=\"x_elementToProof\" data-ogsc=\"rgb(0, 0, 0)\" data-ogsb=\"rgb(255, 255, 255)\">Sujith Ravi is a broadly trained environmental scientist interested in understanding the impacts of land use change and disturbances (natural and anthropogenic) on ecohydrological processes in terrestrial ecosystems. Dr. Ravi&#8217;s research addresses the challenge of managing scarce soil and water resources in the context of multiple demands and multiple constraints associated with land use change and disturbances, the core challenge facing the future of world\u2019s food security and environmental quality. Dr. Ravi received his PhD (2008) in Environmental Sciences (Hydrology) from the University of Virginia. Prior to joining Temple University in 2014, he was a postdoctoral fellow at The Center on Food Security and the Environment at Stanford University. Dr. Ravi\u2019s work has been recognized with a faculty early career award (NSF-CAREER) from the US National Science Foundation, the American Geophysical Union Editors Citation for Excellence in Refereeing, Distinguished Faculty Award for mentoring from Temple University, and Award for Excellence in Scholarship in the Sciences &amp; Engineering from the University of Virginia. Dr. Ravi is currently serving as the Associate Editor of two major journals: Journal of Geophysical Research \u2013 Earth Surface (American Geophysical Union) and Ecosphere (Ecological Society of America).<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Mercoled\u00ec 9 Luglio si terr\u00e0 un seminario presso l\u2019aula Castigliano (Edificio 5) dalle ore 10:00 dal titolo \u201cDesertification pathways induced by rapid vegetation transformations: from shrub encroachment to exotic grass&#8230;<\/p>\n","protected":false},"author":6,"featured_media":26336,"template":"","meta":{"_acf_changed":false,"inline_featured_image":false,"_price":"","_stock":"","_tribe_ticket_header":"","_tribe_default_ticket_provider":"","_tribe_ticket_capacity":"0","_ticket_start_date":"","_ticket_end_date":"","_tribe_ticket_show_description":"","_tribe_ticket_show_not_going":false,"_tribe_ticket_use_global_stock":"","_tribe_ticket_global_stock_level":"","_global_stock_mode":"","_global_stock_cap":"","_tribe_rsvp_for_event":"","_tribe_ticket_going_count":"","_tribe_ticket_not_going_count":"","_tribe_tickets_list":"[]","_tribe_ticket_has_attendee_info_fields":false,"_tribe_events_status":"","_tribe_events_status_reason":"","footnotes":"","_tec_slr_enabled":"","_tec_slr_layout":""},"tags":[2086,13,2087,16,2088],"tribe_events_cat":[930],"class_list":["post-31646","tribe_events","type-tribe_events","status-publish","has-post-thumbnail","hentry","tag-desertification","tag-dica","tag-earth-and-environmental-science","tag-polimi","tag-sijith-ravi","tribe_events_cat-seminari","cat_seminari"],"acf":[],"ticketed":false,"_links":{"self":[{"href":"https:\/\/www.dica.polimi.it\/it\/wp-json\/wp\/v2\/tribe_events\/31646","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.dica.polimi.it\/it\/wp-json\/wp\/v2\/tribe_events"}],"about":[{"href":"https:\/\/www.dica.polimi.it\/it\/wp-json\/wp\/v2\/types\/tribe_events"}],"author":[{"embeddable":true,"href":"https:\/\/www.dica.polimi.it\/it\/wp-json\/wp\/v2\/users\/6"}],"version-history":[{"count":0,"href":"https:\/\/www.dica.polimi.it\/it\/wp-json\/wp\/v2\/tribe_events\/31646\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.dica.polimi.it\/it\/wp-json\/wp\/v2\/media?parent=31646"}],"wp:term":[{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.dica.polimi.it\/it\/wp-json\/wp\/v2\/tags?post=31646"},{"taxonomy":"tribe_events_cat","embeddable":true,"href":"https:\/\/www.dica.polimi.it\/it\/wp-json\/wp\/v2\/tribe_events_cat?post=31646"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}