Populational ecology of seven tree species in a selective logging area in Central Amazon

Orientadores: Flavio Antonio Maës dos Santos, Eduardo Martins VenticinqueTese (doutorado) - Universidade Estadual de Campinas, Instituto de BiologiaResumo: Exploração de madeira realizada sob manejo de impacto reduzido tem sido considerada uma forma de auxiliar a refrear o desmatamento na Amazônia. No entanto, poucos dados estão disponíveis para verificar o impacto dessa atividade sobre a floresta, e assim, avaliar o potencial das áreas sob manejo para conservação de habitats. Nessa tese investigamos o impacto da exploração seletiva de madeira na regeneração e dinâmica de cinco espécies comerciais (Goupia glabra, Manilkara huberi, Manilkara bidentata, Minquartia guianensis e Zygia racemosa) e duas não exploradas (Pouteria anomala e Protium hebetatum). Instalamos parcelas permanentes em áreas sem exploração e em talhões com diferentes idades de regeneração após a exploração (2, 5 e 12 anos). Verificamos ocorrência de efeitos da exploração de madeira sobre fatores abióticos, e a relação desses com a regeneração de indivíduos pequenos (10 a 100cm de altura, Capítulo I). Através de modelos e simulações, avaliamos a sustentabilidade dos parâmetros (como ciclo de corte e intensidade de extração) atualmente utilizados nos principais planos de manejo propostos para a Amazônia (Capítulo II). Por fim, avaliamos se variações nas condições luminosas, encontradas nas áreas exploradas, podem alterar a interação herbívoro-planta, resultando em efeitos sobre a mortalidade de jovens (Capítulo III). Nossos resultados apontam para maior luminosidade e fertilidade do solo nas áreas exploradas. Em função do aumento da luz, verificamos também aumento no crescimento, mas que deve persistir apenas até aproximadamente 5 anos após a exploração. Já o aumento da fertilidade do solo encontrado nas áreas exploradas não contribuiu para aumento do crescimento. As taxas de mortalidade foram maiores nas áreas exploradas, mesmo em locais com 12 anos de regeneração. Tais variações nas taxas vitais foram verificadas para espécies comerciais e não comerciais indicando que as alterações ambientais proporcionadas pela exploração afetam também a regeneração das espécies sem valor madeireiro. Encontramos maiores taxas de herbivoria e crescimento nas clareiras e nas áreas exploradas, em função da maior luminosidade. No entanto, enquanto nas áreas controle a herbivoria foi maior nas clareiras que no sub-bosque, respondendo, então, a um aumento de luminosidade, nas áreas exploradas não ocorreu diferença, indicando que as taxas de herbivoria são independentes da intensidade luminosa. A herbivoria foi um fator importante como condicionante da mortalidade dos jovens, mas aparentemente essa interação está influenciando a mortalidade de maneira análoga entre áreas exploradas e controle. Portanto, essa interação não deve ser responsável pela maior mortalidade de jovens encontrada nas áreas exploradas (Capítulo I). As taxas assintóticas de crescimento (ls) encontrados nas áreas controle indicam estabilidade ou crescimento populacional, dependendo da espécie. Já nas áreas exploradas encontramos ls que indicam declínio das populações, com exceção de P. hebetatum, espécie não explorada. Deste modo, concluímos que a exploração de madeira não é sustentável, mesmo considerando as melhores técnicas de extração praticadas no Brasil. Aparentemente, a mortalidade de jovens (verificada no Capítulo I) e a intensidade de corte são fatores determinantes das taxas de crescimento populacional encontradas nas áreas exploradasAbstract: Reduced-impact logging systems have been considered one way to diminish deforestation rate in Amazonia. However, we do not have enough knowledge about the effects of such systems, due to a lack of data about regeneration and dynamics of tree species. In this thesis we investigated the impact of selective logging on regeneration and dynamics of five commercial species (Goupia glabra, Manilkara huberi, Manilkara bidentata, Minquartia guianensis and Zygia racemosa) and two non-exploited species (Pouteria anomala and Protium hebetatum). We investigated effects of selective logging on the abiotic factors as well as in the regeneration of small individuals (10 to 100cm tall, Chapter I). Through models and simulations, we verified the sustainability of the parameters currently used in the major management plans, proposed for logging activities in Amazon (Chapter II). Finally, we assessed whether variations in light conditions found in the exploited areas could change herbivore-plant interactions, resulting in effects on the mortality of small individuals and their regeneration. Our results pointed to higher light and soil fertility in the exploited areas. We also found an increment in growth rate, due to canopy opening, which should last five years after exploitation. The higher soil fertility found in the exploited areas did not increase the growth rate. The mortality rate was higher in the exploited areas, even in those after 12 year regeneration period. The variation in the vital rates was verified in both exploited and non exploited species, which indicates that logging environmental alteration might also affect the regeneration of noncommercial species. We found higher herbivory and growth rates in gaps and in exploited areas, due to higher light intensity. However, in the control areas the herbivory was higher in the gaps than in the understory, thus responding to the increase in light conditions. In the exploited areas, the herbivore rate was the same in gaps and understory. Herbivory was an important factor conditioning the mortality of small individuals, but this interaction has equally influenced mortality in exploited and non-exploited areas. Therefore, this interaction should not be considered a cause of higher small individuals mortality rates found in the exploited areas. Population growth rates indicate stability or population growth of the tree species in the control areas, but in the exploited ones we found a shrinking population (exception to P. hebetatum, non-exploited species). We concluded that the reduced impact selective logging is not sufficient to warrant sustainability. Higher mortality of small individuals and logging intensity seems to be an important factor that contributes to the lower population growth rates verified in the exploited areasDoutoradoEcologiaDoutor em Ecologi

Effects Of Reduced Impact Logging On The Forest Regeneration In The Central Amazonia

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Selective logging can alter the biota (presence of seed source) and distribution of resources (light and soil factors), modifying the performance of seedlings. To evaluate these effects on forest regeneration processes is of critical importance, since reduced impact logging (Rh) has been advocated as a potential tool for conservation. We describe the abiotic alterations caused by selective logging and examine the effect of disturbances on the abundance and performance of seedlings of seven trees species. To test long-term effects we evaluated the regeneration process in a chronosequence spanning 11-years after logging in which 144 plots were sampled, representing an area of 300,000 ha in the central Amazonia. Seedling performance was affected by habitat alterations caused by logging. Growth is enhanced in logged sites for up to three years after logging for all species. However, in five out of seven species, the mortality rates found in logged were higher than the ones in control sites up to 11 years after logging. For most species the presence of a seed source is the most important factor determining the number of regenerating individuals. This effect of dispersal limitation on seedlings can affect tree regeneration on logged areas, since no rules limit the number of individuals per species that can be harvested per hectare. Demographic responses to abiotic alterations resulting from selective logging affect tree species regeneration patterns, and in a long term can influence the structure of tropical forest communities. We concluded that over time the habitat becomes less suitable for species regeneration on logged areas. These results indicate that RIL can have more effects on tree regeneration than previously supposed. Methods to minimize these effects (mainly on survivorship rates) should be considered in future management plans. (C) 2015 Elsevier B.V. All rights reserved.3605259Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundacao Boticario de Protecao Natureza [0722/20062]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)FAPESP [06/04710-9, 06/56981-6

Effects of reduced impact logging on the forest regeneration in the central Amazonia

Selective logging can alter the biota (presence of seed source) and distribution of resources (light and soil factors), modifying the performance of seedlings. To evaluate these effects on forest regeneration processes is of critical importance, since reduced impact logging (Rh) has been advocated as a potential tool for conservation. We describe the abiotic alterations caused by selective logging and examine the effect of disturbances on the abundance and performance of seedlings of seven trees species. To test long-term effects we evaluated the regeneration process in a chronosequence spanning 11-years after logging in which 144 plots were sampled, representing an area of 300,000 ha in the central Amazonia. Seedling performance was affected by habitat alterations caused by logging. Growth is enhanced in logged sites for up to three years after logging for all species. However, in five out of seven species, the mortality rates found in logged were higher than the ones in control sites up to 11 years after logging. For most species the presence of a seed source is the most important factor determining the number of regenerating individuals. This effect of dispersal limitation on seedlings can affect tree regeneration on logged areas, since no rules limit the number of individuals per species that can be harvested per hectare. Demographic responses to abiotic alterations resulting from selective logging affect tree species regeneration patterns, and in a long term can influence the structure of tropical forest communities. We concluded that over time the habitat becomes less suitable for species regeneration on logged areas. These results indicate that RIL can have more effects on tree regeneration than previously supposed. Methods to minimize these effects (mainly on survivorship rates) should be considered in future management plans3605259CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP478843/2006-2; 309458/2013-7; 306595/2014-1sem informação06/04710-9; 06/56981-

Interspecific variation in the defensive responses of ant mutualists to plant volatiles

In ant-plant mutualist systems, ants patrol their host plants and search for herbivores. Such patrolling can be inefficient, however, because herbivore activity is spatio-temporally unpredictable. It has been proposed that rapid and efficient systems of communication between ants and plants, such as volatile compounds released following herbivory, both elicit defensive responses and direct workers to sites of herbivore activity. We performed bioassays in which we challenged colonies of two Amazonian plant-ants, Azteca sp. and Pheidole minutula, with extracts of leaf tissue from (1) their respective host-plant species (Tococa bullifera and Maieta guianensis, both Melastomataceae), (2) sympatric ant-plants from the Melastomataceae, and (3) two sympatric but non-myrmecophytic Melastomataceae. We found that ants of both species responded dramatically to host-plant extracts, and that these responses are greater than those to sympatric myrmecophytes. Azteca sp. also responded to non-myrmecophytes with an intensity similar to that of sympatric ant-plants. By contrast, the response of P. minutula to any non-myrmecophytic extracts was limited. These differences may be driven in part by interspecific differences in nesting behaviour; although P. minutula only nests in host plants, Azteca sp. will establish carton satellite nests on nearby plants. We hypothesize that Azteca sp. must therefore recognize and defend a wider array of species than P. minutula. © 2008 The Linnean Society of London

Statistical modeling of patterns in annual reproductive rates

Reproduction by individuals is typically recorded as count data (e.g., number of fledglings from a nest or inflorescences on a plant) and commonly modeled using Poisson or negative binomial distributions, which assume that variance is greater than or equal to the mean. However, distributions of reproductive effort are often underdispersed (i.e., variance < mean). When used in hypothesis tests, models that ignore underdispersion will be overly conservative and may fail to detect significant patterns. Here we show that generalized Poisson (GP) and Conway-Maxwell-Poisson (CMP) distributions are better choices for modeling reproductive effort because they can handle both overdispersion and underdispersion; we provide examples of how ecologists can use GP and CMP distributions in generalized linear models (GLMs) and generalized linear mixed models (GLMMs) to quantify patterns in reproduction. Using a new R package, glmmTMB, we construct GLMMs to investigate how rainfall and population density influence the number of fledglings in the warbler Oreothlypis celata and how flowering rate of Heliconia acuminata differs between fragmented and continuous forest. We also demonstrate how to deal with zero-inflation, which occurs when there are more zeros than expected in the distribution, e.g., due to complete reproductive failure by some individuals. © 2019 by the Ecological Society of Americ

Statistical modeling of patterns in annual reproductive rates

Reproduction by individuals is typically recorded as count data (e.g., number of fledglings from a nest or inflorescences on a plant) and commonly modeled using Poisson or negative binomial distributions, which assume that variance is greater than or equal to the mean. However, distributions of reproductive effort are often underdispersed (i.e., variance < mean). When used in hypothesis tests, models that ignore underdispersion will be overly conservative and may fail to detect significant patterns. Here we show that generalized Poisson (GP) and Conway-Maxwell-Poisson (CMP) distributions are better choices for modeling reproductive effort because they can handle both overdispersion and underdispersion; we provide examples of how ecologists can use GP and CMP distributions in generalized linear models (GLMs) and generalized linear mixed models (GLMMs) to quantify patterns in reproduction. Using a new R package, glmmTMB, we construct GLMMs to investigate how rainfall and population density influence the number of fledglings in the warbler Oreothlypis celata and how flowering rate of Heliconia acuminata differs between fragmented and continuous forest. We also demonstrate how to deal with zero-inflation, which occurs when there are more zeros than expected in the distribution, e.g., due to complete reproductive failure by some individuals. © 2019 by the Ecological Society of Americ

Demography of the understory herb Heliconia acuminata (Heliconiaceae) in an experimentally fragmented tropical landscape

Habitat fragmentation remains a major focus of research by ecologists decades after being put forward as a threat to the integrity of ecosystems. While studies have documented myriad biotic changes in fragmented landscapes, including the local extinction of species from fragments, the demographic mechanisms underlying these extinctions are rarely known. However, many of them – especially in lowland tropical forests – are thought to be driven by one of two mechanisms: (1) reduced recruitment in fragments resulting from changes in the diversity or abundance of pollinators and seed dispersers or (2) increased rates of individual mortality in fragments due to dramatically altered abiotic conditions, especially near fragment edges. Unfortunately, there have been few tests of these potential mechanisms due to the paucity of long-term and comprehensive demographic data collected in both forest fragments and continuous forest sites. Here we report 11 years (1998-2009) of demographic data from populations of the Amazonian understory herb Heliconia acuminata (LC Rich.) found at Brazil's Biological Dynamics of Forest Fragments Project (BDFFP). The resulting data set comprises >66000 plant×year records of 8586 plants, including 3464 seedlings that became established after the initial census. Seven populations were in experimentally isolated fragments (one in each of four 1-ha fragments and one in each of three 10-ha fragments), with the remaining six populations in continuous forest. Each population was in a 50×100m permanent plot, with the distance between plots ranging from 500 m-60 km. The plants in each plot were censused annually, at which time we recorded, identified, marked, and measured new seedlings, identified any previously marked plants that died, and recorded the size of surviving individuals. Each plot was also surveyed 4-5 times during the flowering season to identify reproductive plants and record the number of inflorescences each produced. These data have been used to investigate topics ranging from the way fragmentation-related reductions in germination influence population dynamics to statistical methods for analyzing reproductive rates. This breadth of prior use reflects the value of these data to future researchers. In addition to analyses of plant responses to habitat fragmentation, these data can be used to address fundamental questions in plant demography, the evolutionary ecology of tropical plants, and for developing and testing demographic models and tools. Though we welcome opportunities to collaborate with interested users, there are no restrictions on the use this data set. However, we do request that those using the data for teaching or research inform us of how they are doing so and cite this paper and the data archive when appropriate. Any publication using the data must also include a BDFFP Technical Series Number in the Acknowledgments. Authors can request this series number upon the acceptance of their article by contacting the BDFFP's Scientific Coordinator or E. M. Bruna.The files are in .csv files and no special programs or software are required to open them. Funding provided by: National Science FoundationCrossref Funder Registry ID: http://dx.doi.org/10.13039/100000001Award Number: 1948607Funding provided by: National Science FoundationCrossref Funder Registry ID: http://dx.doi.org/10.13039/100000001Award Number: 0614339Funding provided by: National Science FoundationCrossref Funder Registry ID: http://dx.doi.org/10.13039/100000001Award Number: 0614149Funding provided by: National Science FoundationCrossref Funder Registry ID: http://dx.doi.org/10.13039/100000001Award Number: 0309819Funding provided by: National Science FoundationCrossref Funder Registry ID: http://dx.doi.org/10.13039/100000001Award Number: 9806351Funding provided by: National Science FoundationCrossref Funder Registry ID: http://dx.doi.org/10.13039/100000001Award Number: 0109226Funding provided by: Smithsonian InstitutionCrossref Funder Registry ID: http://dx.doi.org/10.13039/100000014Award Number: Funding provided by: University of California, DavisCrossref Funder Registry ID: http://dx.doi.org/10.13039/100007707Award Number: Funding provided by: University of California, DavisCrossref Funder Registry ID: http://dx.doi.org/10.13039/100007707Award Number: Funding provided by: National Science FoundationCrossref Funder Registry ID: http://dx.doi.org/10.13039/100000001Award Number: Funding provided by: Ford FoundationCrossref Funder Registry ID: http://dx.doi.org/10.13039/100000010Award Number:The plants in each plot were censused annually, at which time we recorded, identified, marked, and measured new seedlings, identified any previously marked plants that died, and recorded the size of surviving individuals. Each plot was also surveyed 4-5 times during the flowering season to identify reproductive plants and record the number of inflorescences each produced

Growth of an understory herb is chronically reduced in Amazonian forest fragments

The biotic and abiotic changes associated with habitat fragmentation have been shown to have major consequences for plant recruitment and survivorship. However, few studies have quantified the growth of plants that persist in fragments. Over the course of a decade, we measured annual growth of 5200 individuals of the common understory herb Heliconia acuminata (Heliconiaceae) in an experimentally fragmented Amazonian forest. We tested (A) whether annual growth rates were lower in fragments than in continuous forest, and (B) whether cumulative growth rates of plants that survived the entire period were lower in fragments. While mean annual growth rates were often lower in fragments, differences were not significant in any year. After 10 years, however, the cumulative effect was that plants in fragments were significantly smaller. This had a clear demographic consequence - plants in fragments produced fewer inflorescences than plants in continuous forest. Our results demonstrate that chronic reduced individual growth may be an important mechanism contributing to reduced population viability in fragmented forests, and that negative demographic consequences of fragmentation for plants can take years to manifest themselves. © 2010 Elsevier Ltd

ATLANTIC POLLINATION: a data set of flowers and interaction with nectar-feeding vertebrates from the Atlantic Forest

Flowering plant species and their nectar-feeding vertebrates exemplify some of the most remarkable biotic interactions in the Neotropics. In the Brazilian Atlantic Forest, several species of birds (especially hummingbirds), bats, and non-flying mammals, as well as one lizard feed on nectar, often act as pollinators and contribute to seed output of flowering plants. We present a dataset containing information on flowering plants visited by nectar-feeding vertebrates and sampled at 166 localities in the Brazilian Atlantic Forest. This dataset provides information on 1902 unique interactions among 515 species of flowering plants and 129 species of potential vertebrate pollinators and the patterns of species diversity across latitudes. All plant-vertebrate interactions compiled were recorded through direct observations of visits, and no inferences of pollinators based on floral syndromes were included. We also provide information on the most common plant traits used to understand the interactions between flowers and nectar-feeding vertebrates: plant growth form, corolla length, rate of nectar production per hour in bagged flowers, nectar concentration, flower color and shape, time of anthesis, presence or absence of perceptible fragrance by human, and flowering phenology as well as the plant's threat status by International Union for Conservation of Nature (IUCN) classification. For the vertebrates, status of threat by IUCN classification, body mass, bill or rostrum size are provided. Information on the frequency of visits and pollen deposition on the vertebrate's body is provided from the original source when available. The highest number of unique interactions is recorded for birds (1771) followed by bats (110). For plants, Bromeliaceae contains the highest number of unique interactions (606), followed by Fabaceae (242) and Gesneriaceae (104). It is evident that there was geographical bias of the studies throughout the southeast of the Brazilian Atlantic Forest and that most effort was directed to flower-hummingbird interactions. However, it reflects a worldwide tendency of more plants interacting with birds compared with other vertebrate species. The lack of similar protocols among studies to collect basic data limits the comparisons among areas and generalizations. Nevertheless, this dataset represents a notable effort to organize and highlight the importance of vertebrate pollinators in this hotspot of biodiversity on Earth and represents the data currently available. No copyright or proprietary restrictions are associated with the use of this data set. Please cite this data paper when the data are used in publications or scientific events