Sandra Nogué

Looking forward through the past : identification of 50 priority research questions in palaeoecology

Summary 1. Priority question exercises are becoming an increasingly common tool to frame future agendas in conservation and ecological science. They are an effective way to identify research foci that advance the field and that also have high policy and conservation relevance. 2. To date there has been no coherent synthesis of key questions and priority research areas for palaeoecology, which combines biological, geochemical and molecular techniques in order to reconstruct past ecological and environmental systems on timescales from decades to millions of years. 3. We adapted a well-established methodology to identify 50 priority research questions in palaeoecology. Using a set of criteria designed to identify realistic and achievable research goals, we selected questions from a pool submitted by the international palaeoecology research community and relevant policy practitioners. This article is protected by copyright. All rights reserved. Accepted Article 4. The integration of online participation, both before and during the workshop, increased international engagement in question selection. 5. The questions selected are structured around six themes: human–environment interactions in the Anthropocene; biodiversity, conservation, and novel ecosystems; biodiversity over long timescales; ecosystem processes and biogeochemical cycling; comparing, combining and synthesizing information from multiple records; and new developments in palaeoecology. 6. Future opportunities in palaeoecology are related to improved incorporation of uncertainty into reconstructions, an enhanced understanding of ecological and evolutionary dynamics and processes, and the continued application of long-term data for better-informed landscape management. 7. Synthesis Palaeoecology is a vibrant and thriving discipline and these 50 priority questions highlight its potential for addressing both pure (e.g. ecological and evolutionary, methodological) and applied (e.g. environmental and conservation) issues related to ecological science and global change.

The ancient forests of La Gomera, Canary Islands, and their sensitivity to environmental change

Summary 1. Garajonay National Park in La Gomera (Canary Islands) contains one of the largest remnant areas of a forest formation once widespread throughout Europe and North Africa. Here, we aim to address the long-term dynamics (the last 9600 cal. years) of the monteverde forest (laurel forest and Morella-Erica heath) located close to the summit of the National Park (1487 m a.s.l.) and determine past environmental and human impacts. 2. We used palaeoecological (fossil pollen, microscopic and macroscopic charcoal) and multivariate ecological techniques to identify compositional change in the monteverde forest in relation to potential climatic and human influences, based on the analysis of a core site at 1250-m elevation. 3. The regional mid-Holocene change towards drier conditions was matched in this system by a fairly rapid shift in representation of key forest elements, with declines in Canarian palm tree (Phoenix canariensis), Canarian willow (Salix canariensis) and certain laurel forest taxa and an increase in representation of the Morella–Erica woody heath. 4. Charcoal data suggest that humans arrived on the island between about 3000 and 1800 years ago, a period of minimal vegetation change. Levels of burning over the last 800 years are among the lowest of the entire 9600 years. 5. Synthesis. A rapid climatic-induced shift of forest taxa occurred 5500 years ago, with a decrease in hygrophilous species in the pollen record. In contrast, we found no evidence of a significant response to human colonization. These findings support the idea that Garajonay National Park is protecting a truly ancient relict, comprising a largely natural rather than cultural legacy.

Conservation of the Unique Neotropical Vascular Flora of the Guayana Highlands in the Face of Global Warming

VALENTI RULL,∗†† TERESA VEGAS-VILARRUBIA,† SANDRA NOGUE,∗‡ AND OTTO HUBER§∗∗ ∗CSIC-Botanic Institute of Barcelona, Palynology & Paleoecology, Pg. del Migdia s/n, 08038 Barcelona, Spain †University of Barcelona, Department of Ecology, Av. Diagonal 645, 08028 Barcelona, Spain ‡Autonomous University of Barcelona, Department of Animal Biology, Plant Biology and Ecology, Campus Bellaterra, 08193 Barcelona, Spain §Trauttmansdorff Botanical Gardens, Via San Valentino 51a, 39012 Merano, Italy ∗∗Botanical Institute of Venezuela Dr. Tobias Lasser, Av. Salvador Allende, Caracas 1050, Venezuela

Predictability in community dynamics

The coupling between community composition and climate change spans a gradient from no lags to strong lags. The no-lag hypothesis is the foundation of many ecophysiological models, correlative species distribution modelling and climate reconstruction approaches. Simple lag hypotheses have become prominent in disequilibrium ecology, proposing that communities track climate change following a fixed function or with a time delay. However, more complex dynamics are possible and may lead to memory effects and alternate unstable states. We develop graphical and analytic methods for assessing these scenarios and show that these dynamics can appear in even simple models. The overall implications are that (1) complex community dynamics may be common and (2) detailed knowledge of past climate change and community states will often be necessary yet sometimes insufficient to make predictions of a communitys future state.

Reconstructing Holocene vegetation on the island of Gran Canaria before and after human colonization

We provide the first fossil pollen and charcoal analysis from the island of Gran Canaria (Canary Islands). The pollen record obtained from Laguna de Valleseco (870 m a.s.l.) spans the late Holocene (c. 4500–1500 cal. yr BP) and thereby captures the impact of human colonization. During the earliest period, pollen composition resembled contemporary thermophilous communities, with palms (Phoenix canariensis) and junipers (Juniperus cf. turbinata) being the dominant trees, suggesting that these elements were more widespread in the past. Vegetation in Valleseco began to change at around 2300 cal. yr BP, 400 years before the earliest archaeological evidence of human presence in the island (c. 1900 cal. yr BP). Our data show an increased frequency of fires at that time, coinciding with the decline of palms and the increase of grasses, indicating that humans were present and were transforming vegetation, thus showing that the demise of Gran Canaria’s forest began at an early point in the prehistoric occupation of the island. In the following centuries, there were no signs of forest recovery. Pollen from cultivated cereals became significant, implying the introduction of agriculture in the site, by 1800 cal. yr BP. The next shift in vegetation (c. 1600 cal. yr BP) involved the decrease of grasses in favour of shrubs and trees like Morella faya, suggesting that agriculture was abandoned at the site.

Bureaucratic obstruction of conservation science in the Guayana Highlands.

Unfortunately, field research in the area [northern South America Guayana Highlands (GH)] has been stopped for nearly 20 years. Official permits to visit the tepui summits were suspended in 1989, until a detailed management plan could be made (Huber 1995a). Today most of the tepuis are in national parks and other protection areas, and there is also a special policy for their summits (Huber 1995a). There is an administrative process through which fieldwork permits can be obtained, but the process is so difficult that no scientific expedition has been carried out since closure of the area. Studies involving genetic analysis are not allowed. Thus, officials will not consider permit requests that do not explicitly state that no samples will be used for any type of genetic study. This prohibition makes it impossible to develop phylogenetic and phylogeographic surveys, which are crucial to understanding the origin and maintenance of GH biodiversity (Rull 2007).

Island biodiversity conservation needs palaeoecology

The discovery and colonization of islands by humans has invariably resulted in their widespread ecological transformation. The small and isolated populations of many island taxa, and their evolution in the absence of humans and their introduced taxa, mean that they are particularly vulnerable to human activities. Consequently, even the most degraded islands are a focus for restoration, eradication, and monitoring programmes to protect the remaining endemic and/or relict populations. Here, we build a framework that incorporates an assessment of the degree of change from multiple baseline reference periods using long-term ecological data. The use of multiple reference points may provide information on both the variability of natural systems and responses to successive waves of cultural transformation of island ecosystems, involving, for example, the alteration of fire and grazing regimes and the introduction of non-native species. We provide exemplification of how such approaches can provide valuable information for biodiversity conservation managers of island ecosystems.

Climatic and ecological history of Pantepui and surrounding areas with biogeographical and evolutionary considerations

This chapter reviews the available paleoecological information on Pantepui since the Last Glacial Maximum (LGM), in order to reconstruct the ecological dynamics that have led to the present configuration of plant communities and to unravel the potential environmental drivers involved, with emphasis on regional climate changes and fire. To date, no LGM sediments have been retrieved atop the tepuis, so the vegetation of these summits during the last glaciation remains unknown. Some lowland records suggest that cold LGM climates favored downward migration of temperature-sensitive tepuian species, which drove changes in the taxonomic composition of lowland forests. The available paleoecological record of Pantepui ranges from the early Holocene to the present. These records show two contrasting situations. Some tepui summits exhibit a long vegetation constancy extending back to the mid Holocene, whereas others document significant changes in sensitive species that have been associated with regional climatic events such as the Holocene Thermal Maximum (HTM), the latitudinal migration of the Intertropical Convergence Zone (ITCZ), the El Nino-Southern Oscillation (ENSO) variability, or recent climatic shifts such as the Medieval Climatic Anomaly (MCA) or the Little Ice Age (LIA). This has been interpreted in terms of site’s sensitivity and it has been recommended to obtain past records preferably on elevational ecotones, where vertical migrations of species are more easily detected. During the last millennium, fire, most probably of anthropogenic origin and likely originated on the surrounding uplands, has been a major driver of vegetation change on some tepuis. These studies are useful both to understand the biodiversity and composition of present Pantepui plant communities and to test classical biogeographical and evolutionary hypotheses on the origin of biodiversity and endemism patterns.

Cómo la Macaronesia ha influido en nuestra perspectiva sobre los ecosistemas insulares

Puerta-Pinero, A. 2016. Identification and evaluation of afforestations through the Spanish National Forest Inventory. Ecosistemas 25(3): 43-50. Doi.: 10.7818/ECOS.2016.25-3.05 Afforestation programs in Spain were performed mainly between 1930-1970 decades. The study of the state and functioning of these anthropogenic forests has a wide debate among scientists and stakeholders. Forest inventories represent a crucial source of data to evaluate the long-term functioning of these forests at broad spatial scales. This article shows several tools to identify and select plots from the third Spanish Forest Inventory composed by uniform afforestations. The functions intend to facilitate the work of scientists and technicians whose objective could be influenced by the presence or absence of these artificial forest type. Those functions are a first attempt to include or exclude plots that are composed by artificially afforested forests. I also present some preliminary results, and discuss strengths, weaknesses and future directions relative to the use of these functions.

meeting summary: Discussing the latest advances in biogeography with young biogeographers

ISSN 1948‐6596 news and update meeting summary Discussing the latest advances in biogeography with young bio‐ geographers Advances in Biogeography: IBS Early Career Conference – Oxford, UK, 23‐25 September 2011 Last September, the School of Geography and the Biodiversity Institute (University of Oxford) hosted the first International Biogeography Society (IBS) Early Career Conference, which brought together about one hundred biogeographers from sixteen different countries (Fig. 1). This conference of‐ fered young researchers the opportunity to pre‐ sent their work and exchange experiences, as well as to attend a workshop delivered by Robert Whittaker, Editor‐in‐Chief of the Journal of Bio‐ geography, which provided an overview of the publication process. As this summary aims only to provide the main results of the conference rather than a comprehensive account of all sessions, those interested are referred to the full program 1 . Keynote talks were provided by four IBS board members. Kenneth Feeley discussed the impacts of climate change on tropical forests, identifying four possible responses of species to climate change: acclimation, adaptation, migra‐ tion and extinction. Catherine Graham showed how novel tools may help unravel the mechanisms influencing the diversity and structure of hum‐ mingbird assemblages on the Ecuadorian Andes. Michael Dawson described recent advances in marine biogeography, providing an overview of topics such as the relationship between gene flow and range size, and the pelagic larval duration (i.e. how long a species lives as a larva that dwells in the open sea). Lawrence Heaney described two paradigms in island biogeography, the equilibrium and vicariance models, and then identified chal‐ lenges to island models and emerging questions regarding oceanic island biotas. The junior participants presented cutting edge research in ten sessions that covered a broad range of non‐exclusive and interrelated top‐ ics. Starting from a more local scale, in a study on the Bolivian lowland forest Stefan Abrahamczyk found that the relationship between humming‐ birds and their food plants changes flexibly and idiosyncratically with climate. Leticia Ochoa‐ Figure 1. Group picture of the participants in the first IBS Early Career Conference. 1. Available at http://www.biogeography.org/html/Meetings/2011Oxford/ frontiers of biogeography 3.4, 2012 —