Climate change will reduce suitable Caatinga dry forest habitat for endemic plants with disproportionate impacts on specialized reproductive strategies

Global climate change alters the dynamic of natural ecosystems and directly affects species distributions, persistence and diversity. The impacts of climate change may lead to dramatic changes in biotic interactions, such as pollination and seed dispersal. Life history traits are extremely important to consider the vulnerability of a species to climate change, producing more robust models than those based primarily on species distributions. Here, we hypothesized that rising temperatures and aridity will reduce suitable habitats for the endemic flora of the Caatinga, the most diverse dry tropical forest on Earth. Specifically, species with specialized reproductive traits (e.g. vertebrate pollination, biotic dispersal, obligatory cross-pollination) should be more affected by climate change than those with generalist traits. We performed two ecological niche models (current and future) to simulate the effects of climate change on the distribution area of endemic species in relation to life-history traits. We used the MIROC-ESM and CCSM4 models for both intermediate (RCP4.5) and highest predicted (RCP8.5) GHG emission scenarios, with a resolution of 30' (~1 km2). Habitat with high occurrence probability (>80%) of endemic species will be reduced (up to ~10% for trees, ~13% for non-arboreous, 10-28% for species with any pollination/reproductive system), with the greatest reductions for species with specialized reproductive traits. In addition, the likely concentration of endemic plants in the extreme northeastern portion of the Caatinga, in more mesic areas, coincides with the currently most human-modified areas of the ecosystem, which combined with climate change will further contract suitable habitats of endemic species. In conclusion, plant species endemic to the Caatinga are highly vulnerable to even conservative scenarios of future climate change and may lose much of their climatic envelopes. New protected areas should be located in the northeastern portion of the Caatinga, which hosts a more favorable climate, but is currently exposed to escalating agricultural intensification

Neglected diversity of crop pollinators: Lessons from the world’s largest tropical country

We draw attention to potential pollinator species that have not yet been reported as crop pollinators but could likely contribute to agricultural productivity. We refer to this as the neglected diversity of crop pollinators, which we argue should not be excluded from conservation strategies and land-use planning. We used Brazil as case study for at least five main reasons: (1) Brazil is one of the world’s largest food producers and exporters; (2) Tropical agricultural production is highly dependent on pollinators; (3) Brazil is almost certainly the most biologically megadiverse country; (4) Brazil has high diversity of pollinators; (5) Brazil has played a leading international role in environmental sustainability. We estimated that the neglected diversity of bees as potential crop pollinators in Brazil is 88.4%. For vertebrates, the neglected diversity is 95.2%. This means that many yet to be observed plant–pollinator interactions are entirely off the radar in terms of the conservation agenda for agricultural stability

Divergent responses of plant reproductive strategies to chronic anthropogenic disturbance and aridity in the Caatinga dry forest

Anthropogenic disturbance and climate change are major threats to biodiversity persistence and functioning of many tropical ecosystems. Although increases in the intensity of anthropogenic disturbance and climate change are associated with reduced taxonomic, phylogenetic and functional diversities of several organisms, little is known about how such pressures interfere with the distribution of plant reproductive traits in seasonally dry tropical forests. Here we test the hypothesis that individual and combined effects of increasing chronic anthropogenic disturbance and water deficit negatively affect the richness, abundance and diversity of specialized reproductive strategies of native woody plants in the Caatinga dry forest. This study was carried out at the Catimbau National Park, northeastern Brazil (62,294ha). Chronic anthropogenic disturbance intensity was measured through different sources of disturbance (cattle/goat herbivory, wood extraction, and other people pressures). Water deficit data was obtained from hydrological maps and used as a proxy of aridity. We constructed generalized linear models and selected best-supported models for richness, abundance and functional diversity of reproductive traits. We documented that richness and abundance of plants with certain reproductive traits, regardless the specialization, can increase (in 18 out of the 49 trait categories analyzed; e.g. obligatory cross-pollination in response to increases in aridity and wood extraction), be impaired (in 20 categories; e.g. pollination by Sphingids/beetles with increase in aridity), or remain unchanged (in 21 categories; e.g. pollination by vertebrates with increases in chronic anthropogenic disturbance and aridity) with higher disturbance and aridity. There were combined effects of chronic anthropogenic disturbance and aridity on the richness of plants in nine traits (e.g. pollen flowers; dioecious and self-incompatible plants). Aridity affected 40% of the reproductive traits, while chronic anthropogenic disturbance affected 35.5%. The functional diversity of reproductive traits was affected only by disturbance. Changes in plant community structure promoted by chronic anthropogenic disturbance and aridity will likely threaten plant-animal interactions, thereby compromising the functioning of communities and the persistence of biodiversity in the Caatinga

Polinização por beija-flores em remanescente da Mata Atlantica pernambucana, nordeste do Brasil

Orientadores: Marlies Sazima, Isabel Cristina MachadoTese (doutorado) - Universidade Estadual de Campinas, Instituto de BiologiaResumo: A polinização por beija-flores é encontrada em grande número de famílias vegetais sendo este o maior grupo de polinizadores vertebrados de plantas neotropicais. Estudos sobre guildas de polinização são um eficiente meio de se entender a dinâmica de processos ecológicos em ecossistemas naturais. Foi estudada a guilda de plantas ornitófilas em um remanescente da Mata Atlântica Pernambucana, Nordeste do Brasil, no período de maio/1997 a janeiro/1999 e de agosto a dezembro/1999. Foram registradas 27 espécies ornitófilas, tendo sido incluídas no estudo mais duas cujos atributos florais foram compatíveis com outras síndromes de polinização, tendo os beija-flores atuado como polinizadores efetivos e frequentes. Dentre as 29 espécies estudadas, 15 são dicotiledôneas, distribuídas em 11 famílias, e 14 monocotiledôneas, pertencentes a seis famílias, totalizando 17 famílias e 25 gêneros. Bromeliaceae foi a família com maior riqueza de espécies polinizadas por beija-flores constituindo 27,6% do total de espécies da guilda. A maioria das espécies (64,3%) constituiu-se de epífitas, epífitas facultativas ou lianas, seguidas pelas terrestres de hábito herbáceo (17,9%), arbustivo (14,3%) e arbóreo (3,5%). Também a maioria delas apresentou flores vermelhas, vermelho-alaranjadas ou cor-de-rosa (55,2%), do tipo tubo (79,3%), com corolas cujo comprimento médio do tubo foi 31,4 mm. A concentração de açúcares no néctar variou de 10,2 a 46,8% e o volume de 2,5 a 97,4%. A grande maioria das espécies (91,7%) estava em floração no período de chuvas, havendo, entretanto, durante todo o ano espécies floridas. Foram registradas oito espécies de beija-flores visitantes às flores da comunidade estudada, das quais três foram residentes, sendo as demais transitórias. Glaucis hirsuta (Phaethornithinae), devido ao seu comportamento de visita foi considerada como a espécie dominante da comunidade. Comparações com outros estudos com enfoque semelhante permitiram concluir que a estrutura da guilda de plantas ornitófilas estudada foi semelhante a outros estudos realizados em mata atlântica no Sudeste do Brasil, corroborando a riqueza de plantas ornitófilas apontada para este ecossistema. Dentro deste estudo geral da guilda de polinização de espécies ornitófilas, foi feita uma investigação detalhada das espécies de Bromeliaceae e um estudo de caso com uma espécie de Bignoniaceae (Lundia cordata). o estudo com Bromeliaceae enfocou a polinização e a fenologia reprodutiva das oito espécies ornitófilas registradas para a comunidade (Aechmea fulgens, A. muricata, A. tomentosa, Bi/lbergia morelii, Bromelia plumieri, Portea leptantha Ti/landsia gardneri e T. stricta). As espécies florescem seqüencialmente, havendo ao longo de todo o ano espécies em floração. O comprimento médio do tubo da corola das espécies estudadas foi 31,5 mm. A concentração média de açúcares no néctar foi 29,9%, sendo o volume médio 29,4 µl. Verificou-se correlação positiva entre o comprimento da corola e o volume e a concentração média de açúcares no néctar. Cinco espécies de beija-flores visitaram as flores das Bromeliaceae ao longo do ano (Amazilia fimbriata, Eupetomena macroura, Glaucis hirsuta, Phaethomis pretrei e P. rubef). Glaucis hirsuta visitou as espécies com flores mais longas e com néctar mais concentrado. Phaethomis ruber visitou todas as oito espécies, atuando como pilhador em Bi/lbergia morelii, enquanto que P. pretrei foi visto apenas duas vezes visitando flores de Bromelia plumieri. Amazilia fimbriata e Eupetomena macroura visitaram, respectivamente, flores de três e uma espécie, sempre sobrepondo se no uso de néctar com outras espécies de beija-flores. A família Bromeliaceae foi considerada como uma das principais fontes de néctar para os beija-flores da comunidade. O último estudo abordou a ocorrência de nectários nas flores de Lundia cordata (Bignoniaceae), além de aspectos da biologia floral e fenologia desta espécie. Descrevemos pela primeira vez, para o gênero Lundia, nectários situados no tubo da corola. Este gênero é apontado como tendo principalmente flores de engano. As flores de L. corda ta são tubulosas, resupinadas e protândricas, durando dois dias. Há um disco nectarífero vestigial, não funcional, sendo o néctar secretado por tricomas glandulares distribuídos na superfície interna da corola. O néctar é armazenado na base da corola, ilustrando um caso de apresentação secundária. Os tricomas nectaríferos são multicelulares e uniseriados. Três espécies de beija-flores atuaram como polinizadores (Amazilia fimbriata, Eupetomena macroura e Phaethornis pretrel), enquanto que P. ruber, Xy/ocopa sp. e algumas espécies de vespas e mariposas somente pilharam as flores de L. cordataAbstract: Hummingbirds are the major vertebrate pollinators of Neotropical plants, pollination by hummingbird being found in many botanical families. Studies on pollination guilds constitutes an efficient way to understand ecological processes in natural ecosystems. During the period of May/1997 and January/1999 and August to Dezember/1999 we studied the ornithophilous guild of an Atlantic forest remnant in Pernambuco state, northeastern Brazil. Twenty seven ornithophilous plants were registered, but we included also two species that despite not being ornithophilous were efficiently pollinated by hummingbirds. Among these 29 species, 15 are Dicotyledons (11 famílies) and 14 are Monocotyledons (6 famílies), totalling 17 famílies and 25 genera. Bromeliaceae was the richest family with 27,6% of the guild species. Most of the species (64,3%) are epiphytes, facultative epiphytes or vines, followed by herbs (17,9%), shrubs (14,3%) and trees (3,5%). The majority showed red, red-orange or pink flowers (55,2%), with tube corollas (79,3%), measuring 31,4 mm length on average. Sugar concentration in the nectar ranged from 10,2 to 46,8% and the mean nectar volume varied from 2,5 to 97,4%. Although during the whole year one can find ornithophilous species flowering, most of them (91,7%) blooms during the rainy season. Eight species of hummingbird were registered in the community. Three of them were found to be residents, the remain were temporary. Due to the visiting behaviour, Glaucis hirsuta (Phaethornithinae) was considered as the dominant species. Comparisons with other studies on the same subject in southeastern Brazil Atlantic forest revealed similar richness of ornithophilous species. During the guild study two other studies were developed: one with the Bromeliaceae and a case history with Lundia cordata (Bignoniaceae). The first was based on the pollination and reproductive phenology of 8 ornithophilous species of Bromeliaceae (Aechmea fulgens, A. muricata, A. tomentosa, Billbergia morelii, Bromelia plumieri, Portea leptantha Tillandsia gardneri e T. stricta). The species flowered sequentially. The mean corolla tube length was 31,5 mm. Sugar concentration in the nectar was, on average, 29,9%, and the mean nectar volume was 29,4 µl. Positive correlations between corolla length and nectar volume and concentration were detected. Five hummingbird species acted as pollinators of the Bromeliaceae (Amazilia fimbriata, Eupetomena macroura, Glaucis hirsuta, Phaethornis pretrei e P. rubei). Glaucis hirsuta visited the species with the longest tubes and highest nectar concentration. Phaethornis ruber visited ali species, acting as nectar thieves in Billbergia morelli, while P. pretrei was seen just twice, visiting flowers of only one species, Bromelia plumieri. Amazilia fimbriata and Eupetomena macroura visited, respectively, three and one species, always overlapping in the use of nectar with other hummingbird species. Bromeliaceae was considered one of the main sources of nectar to the hummingbirds of the community. The third study reports for the first time corolla-borne nectaries in a species of the neotropical genus Lundia A. DC. (Bignoniaceae). The floral biology, pollination ecology and flowering phenology of Lundia corda ta were investigated. This species is a typically ornithophilous liana, with reddish, tubular, and scentless flowers. The flowers are resupinate, protandrous and last for two days. There is a vestigial non functional perigynous disk and the nectar is secreted by glandular trichomes distributed along the internal surface of the corolla. The nectar is stored at the base of the corolla tube, thus showing secondary nectar presentation. The nectariferous trichomes are multi cellular, uniseriate, with a basal cell (foot) rooting in the epidermis, one neck cell, and a glandular head with 13 cells on average (9-17). Three species of hummingbirds (Amazilia fimbriata, Eupetomena macroura and Phaethornis pretrel) served as pollinators. Phaethornis ruber, Xy/ocopa bees, wasps and diurnal moths were considered nectar thievesDoutoradoBiologia VegetalDoutor em Ciências Biológica

Plant Sexual Systems and a Review of the Breeding System Studies in the Caatinga, a Brazilian Tropical Dry Forest

• Backgrounds and Aims The reproductive biology of a community can provide answers to questions related to the maintenance of the intraspecific pollen flow and reproductive success of populations, sharing and competition for pollinators and also questions on conservation of natural habitats affected by fragmentation processes. This work presents, for the first time, data on the occurrence and frequency of plant sexual systems for Caatinga communities, and a review of the breeding system studies of Caatinga species