Lea de Nascimento

Universidad de La Laguna | ULL · Botany, Ecology and Plant Physiology

São Tomé (Gulf of Guinea, Central Africa) is a 854 km2 tropical island that had a pivotal role in early European colonial expansion through the Atlantic between the 15th and 16th centuries. Historical sources suggest that native vegetation has been heavily impacted since human arrival (1470 CE) due to monoculture economies and the introduction of m...

Palaearctic Erica sect. Chlorocodon, known as the wind-pollinated besom heaths (WPBH), includes the Macaronesian E. azorica, E. platycodon subsp. platycodon and E. platycodon subsp. maderincola together with the Mediterranean and North African E. scoparia. Despite the broad extant distribution, the mainland fossil record of this section is scarce a...

Partial cover page with a photo of a Erica fossil found in a 1.3 Ma sedimentary deposit in Madeira Island.

Human‐mediated changes in island vegetation are, among others, largely caused by the introduction and establishment of non‐native species. However, data on past changes in non‐native plant species abundance that predate historical documentation and censuses are scarce. Islands are among the few places where we can track human arrival in natural sys...

Cabo Verde remained uninhabited until 1460 CE, when European sailors founded a settlement in Santiago, and soon after in Fogo island. The degree to which different island ecosystems in Cabo Verde have been transformed by humans remains uncertain because of a scarcity of historical information and archaeological evidence. Disentangling these process...

Islands contribute enormously to global biodiversity, but are threatened by human activities. The emergence of island societies has transformed island ecosystems since prehistory. Focusing on drivers of change related to human activities, such as land(sea)-use change, resource extraction, pollution, invasive and alien species, and climate change, w...

Oceanic islands are renowned for their unique flora and high levels of endemism. Native island plants, however, are imperilled by non-native species that can become invasive by outcompeting natives. The threat of native island assemblages generally increases with isolation and the number of endemics featured, but also with human-associated disturba...

Questions Pollen traits (e.g., size, wall thickness, number of apertures) have been suggested to be relevant in terms of pollination mechanisms and the ability of the male gametophyte to withstand desiccation. We examined the spatiotemporal distribution of pollen traits related to dispersal (ornamentation and dispersal unit) and desiccation toleran...

Significance Assessing the ecological consequences of human settlement can help preserve island forests and their ecosystem services, but to understand the legacy of these interactions requires datasets that span centuries. We used paleoecological data (e.g. fossil pollen) to show that prehuman Holocene forests were dynamic in response to climatic...

Research in Macaronesia has led to substantial advances in ecology, evolution and conservation biology. We review the scientific developments achieved in this region, and outline promising research avenues enhancing conservation. Some of these discoveries indicate that the Macaronesian flora and fauna is composed of rather young lineages, not Terti...

Despite islands contributing only 6.7% of land surface area, they harbor ~20% of the Earth’s biodiversity, but unfortunately also ~50% of the threatened species and 75% of the known extinctions since the European expansion around the globe. Due to their geological and geographic history and characteristics, islands act simultaneously as cradles of...

Insular woodiness (IW), referring to the evolutionary transition from herbaceousness toward woodiness on islands, has arisen more than 30 times on the Canary Islands (Atlantic Ocean). One of the IW hypotheses suggests that drought has been a major driver of wood formation, but we do not know in which palaeoclimatic conditions the insular woody line...

Accelerating ecosystem disruption Oceanic islands are among the most recent areas on Earth to have been colonized by humans, in many cases in just the past few thousand years. Therefore, they are important laboratories for the study of human impacts on natural vegetation and biodiversity. Nogué et al. provide a quantitative palaeoecological study o...

New Zealand’s iconic, flightless and endangered species of kiwi (Apterygidae) are at risk of extinction on the mainland due to predation by introduced mammals. In order to provide effective conservation management a robust understanding of genetic variation in the group is needed. Recent genomic analyses of kiwi suggest that several cryptic and as...

Aim Palaeoecological data provide an essential long‐term perspective of ecological change and its drivers in oceanic islands. However, analysing the effects of multi‐scalar and potentially co‐occurring disturbances is particularly challenging in dry islands. Here, we aim to identify the ecological consequences of the integrated impacts of a regiona...

Aim Long‐term ecological data provide a stepped frame of island ecosystem transformation after successive waves of human colonization, essential to determine conservation and management baselines. However, the timing and ecological impact of initial human settlement on many islands is still poorly known. Here, we report analyses from a 4800‐year se...

Oceanic islands remained free of humans until relatively recent times. On contact, humans encountered pristine environments with unique ecosystems and species highly vulnerable to novel impacts. In the course of rendering an island habitable, the new settlers transformed it through fire, deforestation, hunting and introduction of pests and weeds. T...

Islands contribute enormously to global biodiversity, but their species and ecosystems are highly threatened and often confined to small patches of remaining native vegetation. Islands are thus ideal microcosms to study the local dimensions of global change. While human activities have drastically transformed most islands, the extent to which socie...

Aim: Insular woodiness, referring to the evolutionary transition from herbaceousness towards woodiness on islands, has arisen at least 38 times on the Canary Islands. Distribution patterns and physiological experiments have suggested a link between insular woodiness and increased drought stress resistance in current-day species, but we do not know...

Confined to the humid cloud belt of the Macaronesian Islands the Laurel-forests are sensitive to climate changes. Intense natural disturbances are rare and regeneration includes asexual regeneration and dominance of shade intolerant species in the seedling bank. Long-term monitoring of the seedling bank showed that even under these relatively stabl...

The Walker and Syers model predict that phosphorus (P) availability decreases with time leading to a final stage known as retrogression. We tested the validity of the Walker and Syers model in the Canary Islands, a soil chronosequence ranging from 300 years to 11 million years under recurrent episodes of atmospheric dust-containing P inputs. In par...

Laurus azorica wood anatomy: detail in TLS of the vessels, showing simple perforation plates (Fig. 5F in the paper)

A popular article on the Juniper (Juniperus turbinata ssp. canariensis) woodlands of the Canary Islands, with information and photos of different landscapes, trees, plant species and birds associated to this type of forests. There are also detailed maps showing the distribution of such woodlands in all the islands. Published in Rincones del Atlánti...

Terceira island (Azores archipelago, central Atlantic Ocean) presents a unique but poorly studied Quaternary palaeobotanical record. Among the sites referenced in the literature, Fanal Bay, within Angra do Heroísmo city, is known at least since the 1940’s. Field prospection in the summer of 2016 revealed two layers of leaf fossils with an unexpecte...

Plants on oceanic islands can evolve insular syndromes such as secondary woodiness, a generalized trend found in island floras worldwide. This phenomenon occurs through evolution in situ. It is triggered by ecological and physiological stimuli that transform herbaceous annuals into woody perennials. However, well-dated and informative fossils that...

Top left corner: Melanoselinum decipiens, a neoendemic plant from Madeira Island.

Plant fossils are known from the Azores Islands, yet poorly studied. We present a comprehensive bibliographical review for the archipelago. A first pre-scientific reference dates from late 16th century, while the first scientific description was reported in 1821, accounting for trunks in pyroclastic units and silicified plants within hydrothermal d...

Endemics–Area Relationships (EARs)are fundamental in theoretical and applied biogeography for understanding distribution patterns and promoting biodiversity conservation. However, calculating EARs for vascular plant species from existing data is problematic because of biased knowledge of endemic species distributions and differences between taxonom...

In Tenerife (Canary Islands), the laurel forest is considered one of the most biodiverse ecosystems of the archipelago. This study aims at providing useful information about tree species strategies and their natural dynamics in order to improve understanding of the functioning of this ecosystem. The knowledge gained would be of great importance for...

Understanding patterns of community structure and the causes for their variation can be furthered by comparative biogeographic analyses of island biotas. We used woody plant data at the local scale to investigate variations in species rarity, alpha, beta, and gamma diversity within and between three islands from the oceanic archipelagoes of Azores,...

Aim To quantify the influence of past archipelago configuration on present‐day insular biodiversity patterns, and to compare the role of long‐lasting archipelago configurations over the Pleistocene to configurations of short duration such as at the Last Glacial Maximum (LGM) and the present‐day. Location 53 volcanic oceanic islands from 12 archipe...

Well age-constrained and taxonomically determined plant fossils are crucial for providing independent minimum ages for molecular phylogenetic dating. In oceanic Islands these are especially useful for taxa that evolved in insular ecosystems. In this study, we have revisited the fossil plant bed of Porto da Cruz on Madeira Island (Portugal), to gain...

Fossil flowers from Madeira Island were first described by Oswald Heer (1809-1883) in his pivotal paper dealing with the Mio-Pleistocene São Jorge fossil flora. Since Heer’s paper, and due to a long lag (more than 150 years) of palaeobotanical investigations in Madeira Island, no further fossil flowers were found or described. Recent field and labo...

Bryophyta spore fossils are present in the palaeoecological reconstructions for every Late Pleistocene to Holocene sediment cores from lakes, ponds and peat bogs from Macaronesia. Gametophyte and sporophyte somatofossils from Holocene or Late Pleistocene, certainly are present in many of these sedimentary cores (and especially in peat bogs) but w...

Well age-constrained and taxonomically determined plant fossils are crucial for providing independent minimum ages for molecular phylogenetic dating. In oceanic Islands these are especially useful for taxa that evolved in insular ecosystems. In Macaronesian Islands, recent studies propose molecular dating for several plant families and genera but t...

Due to their geology, isolation and relatively recent human colonization, oceanic Islands have been, since Darwin and Wallace's proposal of the evolution by natural selection, the ideal sites to observe and study ecological and evolutionary processes. Although these islands were recently settled, the rapid anthropogenic modification and the relativ...

The recovery and survival of the Macaronesian laurel forest depends on its regeneration strategies. After years of long-term monitoring, both sexual and asexual regeneration appear to be equally important. However, the mechanisms for each are just beginning to be understood. In order to contribute to the understanding of the laurel forest sexual re...

Macaronesia, History, Plant fossils, Palaeoecology, Biogeography

Aim The majority of documented extinctions world‐wide in the last four centuries are of species endemic to islands. However, the phenomenon of delayed extinctions as a result of habitat loss has rarely been assessed on oceanic islands. In this study, we tested whether extinction debt ( ED ), in general, occurs on islands and for which taxonomical g...

In the early 15th century, when the Portuguese Madeira and Azores archipelagos were settled, the islands were described as presenting luxurious and pristine forests. Since then the vegetation suffered overexploitation, area loss, degradation, extirpation and extinction, while numerous new species were introduced from all over the world. Anthropic i...

The discovery and colonisation 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 degrade...

Aims The 50th anniversary of the publication of the seminal book, The Theory of Island Biogeography, by Robert H. MacArthur and Edward O. Wilson is a timely moment to review and identify key research foci that could advance island biology. Here, we take a collaborative horizon-scanning approach to identify 50 fundamental questions for the continued...

Past climate dynamics have helped shape the endemic ecosystems of Macaronesia. However, these insular ecosystems have since been modified following the arrival of human settlers, who had to adapt to the new environments and resources.

On volcanic islands, the interaction between explosive volcanic events and the vegetation creates ideal taphonomical settings for plants and soils to be buried and preserved. In the Azores Islands the palaeobotanical record is linked with the volcanic activity. Although plant macrofossils have been known since the 19th century, palaeovegetation div...

The subaerial evolution of volcanic islands, characterized by recurrent and varied volcanic activity alternating with quiescence, erosion and sedimentation periods, provides, from a taphonomical point of view, excellent opportunities for palaeovegetation to be preserved as fossils. The palaeobotanical history of the Portuguese Macaronesian Islands,...

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 t...

Although the role that Pleistocene glacial cycles have played in shaping the present biota of oceanic islands world-wide has long been recognized, their geographical, biogeographical and ecological implications have not yet been fully incorporated within existing biogeographical models. Here we summarize the different types of impacts that glacial...

Key message The long-term effect of forest fires in the regeneration ofPinus canariensiswas studied. Forest fires had little long-term effects on seed production, seedling germination and seedling mortality. The characteristics of different forest stands across the island had influence in some of the regeneration parameters studied.ContextDespite t...

Since the early 19th century, there are frequent reports of the occurrence of macrofossil plant remains in the Portuguese Macaronesian islands. Charcoal, wood, peat and palaeosoils have been used for radiocarbon dating of volcanic events in both archipelagos. However there is a paucity of palaeobotanical and palaeopalynological studies. The remains...

Vegetation history in the Canary Islands, one of the most biodiverse regions within Europe, has recently and for the first time, been the subject of palaeoecological studies. The interpretation of fossil records may be limited by several uncertainties regarding how well the different vegetation types are represented in the pollen rain. In this stud...

As a working hypothesis, we examined evidence for the former presence of a climacic woodland of Juniperus cedrus above the pine forest in the high elevation area of Tenerife (Canary Islands), which would indicate that the current dominant vegetation (endemic Spartocytisus supranubius scrub) may not be pristine. The main causes of the great regressi...

Sustainable grazing in natural protected areas is a complex planning target. In this work, research was done by three different approaches, 1) assessment of the stocking rate (SR), carrying capacity (CC) and utilization rate (UR) 2) spatial analysis and 3) participatory rural appraisal (PRA), aiming to determine the factors involved in the selectio...

The history of the recent past landscape and vegetation change in the Canary Islands has been recently afforded by a paleoecological project focusing on former lakes sedimentary successions from Tenerife and La Gomera (de Nascimento et al., 2009; Nogué et al., 2013). These records, spanning the last 5 and 9 ka respectively, highlighted substantial...

Seedling dynamics of the Macaronesian laurel forest have been monitored for the first time in a long-term study to determine whether the survival of the seedling community is affected by slope aspect and forest structure. More than 4000 seedlings were monitored monthly from 2000 to 2003 in well-preserved laurel forest stands on Tenerife, Canary Isl...

Vegetation dynamics since the last glacial maximum in small oceanic islands and in continental settings are compared. We selected the islands of Minorca (Western Mediter- ranean), Tenerife (Eastern Atlantic), the Azores (Central Atlantic) and Mauritius (Indian Ocean) and compared pollen-based dynamics with selected continental areas of southern...

Three natural forest formations are distributed today in the Canary Islands archipelago: the pine, the laurel, or Monteverde, and thermophilic forests. Despite its importance, the regeneration of these ecosystems has been insufficiently studied, especially in the thermophilic forest, one of the most severely degraded ecosystems in the islands. In t...

In this study, we inquire into the effects of short-term goat grazing abandonment on plant species and functional composition, bare ground and net primary productivity (NPP) in two traditionally grazed pastures located in the Canarian Network of Natural Protected Areas and the Natura 2000 Network. In addition, we analyse soil chemical properties, b...

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 Nation...

Question How are semi-natural ecosystems affected by goat grazing regime (heavy, light and long-term abandonment)? Location Anaga Rural Park, Tenerife Island, Canary Islands (Spain). Methods We evaluated plant species composition, diversity and structure (frequencies of functional groups based on growth form and bare ground) for three goat gra...

The geomorphological dynamics of the Barranco de Taburiente gorge, in La Palma (Canary Islands), has exposed sub-fossil organic layers in its riverbanks and margins, in which a large number of woody remains have been recovered. Samples have been located along ~3 km of the river and are clustered in three sites. Radiocarbon dating of the remains ind...