Browsing by Author "Holmgren, Milena"

Now showing 1 - 4 of 4
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    Can we infer plant facilitation from remote sensing? a test across global drylands
    (2015) Xu, Chi; Holmgren, Milena; Van Nes, Egbert H.; Maestre, Fernando T.; Soliveres, Santiago; Berdugo, Miguel; Kéfi, Sonia; Marquet, P. A. (Pablo A.); Abades T., Sebastián R.; Scheffer, Marten
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    Extreme climatic events shape arid and semiarid ecosystems
    (2006) Holmgren, Milena; Jaksic Andrade, Fabián; Lima Arce, Mauricio
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    Priority questions for biodiversity conservation in the Mediterranean biome: Heterogeneous perspectives across continents and stakeholders
    (2019) Moreira, Francisco; Allsopp, Nicky; Esler, Karen J.; Wardell-Johnson, Grant; Ancillotto, Leonardo; Arianoutsou, Margarita; Clary, Jeffrey; Brotons, Lluis; Clavero, Miguel; Dimitrakopoulos, Panayiotis G.; Fagoaga, Raquel; Fiedler, Peggy; Filipe, Ana F.; Frankenberg, Eliezer; Holmgren, Milena; Marquet, Pablo A.; Martinez-Harms, Maria J.; Martinoli, Adriano; Miller, Ben P.; Olsvig-Whittaker, Linda; Pliscoff, Patricio; Rundel, Phil; Russo, Danilo; Slingsby, Jasper A.; Thompson, John; Wardell-Johnson, Angela; Beja, Pedro
    The identification of research questions with high relevance for biodiversity conservation is an important step towards designing more effective policies and management actions, and to better allocate funding among alternative conservation options. However, the identification of priority questions may be influenced by regional differences in biodiversity threats and social contexts, and to variations in the perceptions and interests of different stakeholders. Here we describe the results of a prioritization exercise involving six types of stakeholders from the Mediterranean biome, which includes several biodiversity hotspots spread across five regions of the planet (Europe, Africa, North and South America, and Australia). We found great heterogeneity across regions and stakeholder types in the priority topics identified and disagreement among the priorities of research scientists and other stakeholders. However, governance, climate change, and public participation issues were key topics in most regions. We conclude that the identification of research priorities should be targeted in a way that integrates the spectrum of stakeholder interests, potential funding sources and regional needs, and that further development of interdisciplinary studies is required. The key questions identified here provide a basis to identify priorities for research funding aligned with biodiversity conservation needs in this biome.
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    Species interactions across trophic levels mediate rainfall effects on dryland vegetation dynamics
    (2021) Farias, Ariel A.; Armas, Cristina; Gaxiola, Aurora; Cea, Alex P.; Luis Cortes, Jose; Lopez, Ramiro P.; Casanoves, Fernando; Holmgren, Milena; Meserve, Peter L.; Gutierrez, Julio R.; Kelt, Douglas A.
    Arid ecosystems are strongly limited by water availability, and precipitation plays a major role in the dynamics of all species in arid regions, as well as the ecosystem processes that occur there. However, understanding how biotic interactions mediate long-term responses of dryland ecosystems to rainfall remains very fragmented. We report on a unique large-scale field experiment spanning 25 yr and three trophic levels (plants, small mammal herbivores, predators) in a dryland ecosystem in the northern Chilean Mediterranean Region where we assessed how biotic interactions influence the long-term plant community responses to precipitation. As the most persistent ecological changes in dryland systems may result from changes in the structure, cover, and composition of the perennial vegetation, we emphasized the interplay between bottom-up and top-down controls of perennial plants in our analyses. Rainfall was the primary factor affecting the dynamics of, and interactions among, plants and small mammals. Ephemeral plant cover dynamics closely tracked short-term annual rainfall, but seemed unaffected by top-down controls (herbivory). In contrast, the response of the perennial plant cover to precipitation was mediated by (1) a complex interplay between subtle top-down (herbivory) controls that become more apparent in the long-term, (2) competition with ephemeral plants during wet years, and (3) an indirect effect of predators on subdominant shrubs and perennial herbs. This long-term field experiment highlights how climate-induced responses of arid perennial vegetation are influenced by interactions across trophic levels and temporal scales. In the face of global change, understanding how multi-trophic controls mediate dryland vegetation responses to climate is essential to properly managing the conservation of biodiversity in arid systems.