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  • 1
    Online Resource
    Online Resource
    Spatial trends in leaf size of Amazonian rainforest trees
    Copernicus GmbH ; 2009
    In:  Biogeosciences Vol. 6, No. 8 ( 2009-08-10), p. 1563-1576
    Details
    In: Biogeosciences, Copernicus GmbH, Vol. 6, No. 8 ( 2009-08-10), p. 1563-1576
    Abstract: Abstract. Leaf size influences many aspects of tree function such as rates of transpiration and photosynthesis and, consequently, often varies in a predictable way in response to environmental gradients. The recent development of pan-Amazonian databases based on permanent botanical plots has now made it possible to assess trends in leaf size across environmental gradients in Amazonia. Previous plot-based studies have shown that the community structure of Amazonian trees breaks down into at least two major ecological gradients corresponding with variations in soil fertility (decreasing from southwest to northeast) and length of the dry season (increasing from northwest to south and east). Here we describe the geographic distribution of leaf size categories based on 121 plots distributed across eight South American countries. We find that the Amazon forest is predominantly populated by tree species and individuals in the mesophyll size class (20.25–182.25 cm2). The geographic distribution of species and individuals with large leaves (〉20.25 cm2) is complex but is generally characterized by a higher proportion of such trees in the northwest of the region. Spatially corrected regressions reveal weak correlations between the proportion of large-leaved species and metrics of water availability. We also find a significant negative relationship between leaf size and wood density.
    Type of Medium: Online Resource
    ISSN: 1726-4189
    URL: Article
    DOI: 10.5194/bg-6-1563-2009
    Language: English
    Publisher: Copernicus GmbH
    Publication Date: 2009
    detail.hit.zdb_id: 2158181-2
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  • 2
    Online Resource
    Online Resource
    Spatial distribution and functional significance of leaf lamina shape in Amazonian forest trees
    Copernicus GmbH ; 2009
    In:  Biogeosciences Vol. 6, No. 8 ( 2009-08-10), p. 1577-1590
    Details
    In: Biogeosciences, Copernicus GmbH, Vol. 6, No. 8 ( 2009-08-10), p. 1577-1590
    Abstract: Abstract. Leaves in tropical forests come in an enormous variety of sizes and shapes, each of which can be ultimately viewed as an adaptation to the complex problem of optimising the capture of light for photosynthesis. However, the fact that many different shape "strategies" coexist within a habitat demonstrate that there are many other intrinsic and extrinsic factors involved, such as the differential investment in support tissues required for different leaf lamina shapes. Here, we take a macrogeographic approach to understanding the function of different lamina shape categories. Specifically, we use 106 permanent plots spread across the Amazon rainforest basin to: 1) describe the geographic distribution of some simple metrics of lamina shape in plots from across Amazonia, and; 2) identify and quantify relationships between key environmental parameters and lamina shape in tropical forests. Because the plots are not randomly distributed across the study area, achieving this latter objective requires the use of statistics that can account for spatial auto-correlation. We found that between 60–70% of the 2791 species and 83 908 individual trees in the dataset could be classified as having elliptic leaves (= the widest part of the leaf is on an axis in the middle fifth of the long axis of the leaf). Furthermore, the average Amazonian tree leaf is 2.5 times longer than it is wide and has an entire margin. Contrary to theoretical expectations we found little support for the hypothesis that narrow leaves are an adaptation to dry conditions. However, we did find strong regional patterns in leaf lamina length-width ratios and several significant correlations with precipitation variables suggesting that water availability may be exerting an as yet unrecognised selective pressure on leaf shape of rainforest trees. Some support was found for the hypothesis that narrow leaves are an adaptation to low nutrient soils. Furthermore, we found a strong correlation between the proportion of trees with non-entire laminas (dissected, toothed, etc.) and mean annual temperature once again supporting the well documented association that provides a basis for reconstructing past temperature regimes.
    Type of Medium: Online Resource
    ISSN: 1726-4189
    URL: Article
    DOI: 10.5194/bg-6-1577-2009
    Language: English
    Publisher: Copernicus GmbH
    Publication Date: 2009
    detail.hit.zdb_id: 2158181-2
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  • 3
    Online Resource
    Online Resource
    Life history patterns of river invertebrates
    Springer Science and Business Media LLC ; 1992
    In:  Hydrobiologia Vol. 248, No. 1 ( 1992-11), p. 31-37
    Details
    In: Hydrobiologia, Springer Science and Business Media LLC, Vol. 248, No. 1 ( 1992-11), p. 31-37
    Type of Medium: Online Resource
    ISSN: 0018-8158 , 1573-5117
    URL: Article
    DOI: 10.1007/BF00008883
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 1992
    detail.hit.zdb_id: 1478162-1
    detail.hit.zdb_id: 214428-1
    SSG: 12
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  • 4
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    Online Resource
    The ghosts of forests past and future: deforestation and botanical sampling in the Brazilian Amazon
    Wiley ; 2020
    In:  Ecography Vol. 43, No. 7 ( 2020-07), p. 979-989
    Details
    In: Ecography, Wiley, Vol. 43, No. 7 ( 2020-07), p. 979-989
    Abstract: The remarkable biodiversity of the Brazilian Amazon is poorly documented and threatened by deforestation. When undocumented areas become deforested, in addition to losing the fauna and flora, we lose the opportunity to know which unique species had occupied a habitat. Here we quantify such knowledge loss by calculating how much of the Brazilian Amazon has been deforested and will likely be deforested until 2050 without having its tree flora sufficiently documented. To this end, we analysed 399 147 digital specimens of nearly 6000 tree species in relation to official deforestation statistics and future deforestation scenarios. We find that by 2017, 30% of all the localities where tree specimens had been collected were mostly deforested. Some 300 000 km 2 (12%; 485 25 × 25 km grid cells) of the Brazilian Amazon had been deforested by 2017, without having a single tree specimen recorded. An additional 250 000–900 000 km 2 of severely under‐collected rainforest will likely become deforested by 2050. If future tree sampling is to cover this area, sampling effort has to increase two‐ to six‐fold. Nearly 255 000 km 2 or 7% of rainforest in the Brazilian Amazon is easily accessible but does yet but remain under‐collected. Our study highlights how progressing deforestation increases the risk of losing undocumented species of a hyper‐diverse tree flora.
    Type of Medium: Online Resource
    ISSN: 0906-7590 , 1600-0587
    URL: Issue
    URL: Article
    DOI: 10.1111/ecog.2020.v43.i7
    DOI: 10.1111/ecog.05026
    Language: English
    Publisher: Wiley
    Publication Date: 2020
    detail.hit.zdb_id: 2024917-2
    detail.hit.zdb_id: 1112659-0
    SSG: 12
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  • 5
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    Online Resource
    Drivers of taxonomic bias in conservation research: a global analysis of terrestrial mammals
    Wiley ; 2020
    In:  Animal Conservation Vol. 23, No. 6 ( 2020-12), p. 679-688
    Details
    In: Animal Conservation, Wiley, Vol. 23, No. 6 ( 2020-12), p. 679-688
    Abstract: Scientific knowledge of species and the ecosystems they inhabit is the cornerstone of modern conservation. However, research effort is not spread evenly among taxa (taxonomic bias), which may constrain capacity to identify conservation risk and to implement effective responses. Addressing such biases requires an understanding of factors that promote or constrain the use of a particular species in research projects. To this end, we quantified conservation science knowledge of the world’s extant non‐marine mammal species ( n  = 4108) based on the number of published documents in journals indexed on Clarivate Analytics’ Web of Science ™. We use an innovative hurdle model approach to assess the relative importance of several ecological, biogeographical and cultural factors for explaining variation in research production between species. The most important variable explaining the presence/absence of conservation research was scientific capacity of countries within the range of the species, followed by body mass and years since the taxonomic description. Research volume (more than one document) was strongly associated with number of years since the data describing on that species, followed by scientific capacity within the range of species, high body mass and invasiveness. The threat status was weakly associated to explain the presence/absence and research volume in conservation research. These results can be interpreted as a consequence of the dynamic interplay between the perceived need for conservation research about a species and its appropriateness as a target of research. As anticipated, the scientific capacity of the countries where a species is found is a strong driver of conservation research bias, reflecting the high variation in conservation research funding and human resources between countries. Our study suggests that this bias could be most effectively reduced by a combination of investing in pioneering research, targeted funding and supporting research in countries with low scientific capacity and high biodiversity.
    Type of Medium: Online Resource
    ISSN: 1367-9430 , 1469-1795
    URL: Issue
    URL: Article
    DOI: 10.1111/acv.v23.6
    DOI: 10.1111/acv.12586
    Language: English
    Publisher: Wiley
    Publication Date: 2020
    detail.hit.zdb_id: 1481960-0
    SSG: 12
    SSG: 23
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  • 6
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    Online Resource
    Influence of landscape heterogeneity on spatial patterns of wood productivity, wood specific density and above ground biomass in Amazonia
    Copernicus GmbH ; 2009
    In:  Biogeosciences Vol. 6, No. 9 ( 2009-09-08), p. 1883-1902
    Details
    In: Biogeosciences, Copernicus GmbH, Vol. 6, No. 9 ( 2009-09-08), p. 1883-1902
    Abstract: Abstract. Long-term studies using the RAINFOR network of forest plots have generated significant insights into the spatial and temporal dynamics of forest carbon cycling in Amazonia. In this work, we map and explore the landscape context of several major RAINFOR plot clusters using Landsat ETM+ satellite data. In particular, we explore how representative the plots are of their landscape context, and test whether bias in plot location within landscapes may be influencing the regional mean values obtained for important forest biophysical parameters. Specifically, we evaluate whether the regional variations in wood productivity, wood specific density and above ground biomass derived from the RAINFOR network could be driven by systematic and unintentional biases in plot location. Remote sensing data covering 45 field plots were aggregated to generate landscape maps to identify the specific physiognomy of the plots. In the Landsat ETM+ data, it was possible to spectrally differentiate three types of terra firme forest, three types of forests over Paleovarzea geomorphologycal formation, two types of bamboo-dominated forest, palm forest, Heliconia monodominant vegetation, swamp forest, disturbed forests and land use areas. Overall, the plots were generally representative of the forest physiognomies in the landscape in which they are located. Furthermore, the analysis supports the observed regional trends in those important forest parameters. This study demonstrates the utility of landscape scale analysis of forest physiognomies for validating and supporting the finds of plot based studies. Moreover, the more precise geolocation of many key RAINFOR plot clusters achieved during this research provides important contextual information for studies employing the RAINFOR database.
    Type of Medium: Online Resource
    ISSN: 1726-4189
    URL: Article
    DOI: 10.5194/bg-6-1883-2009
    Language: English
    Publisher: Copernicus GmbH
    Publication Date: 2009
    detail.hit.zdb_id: 2158181-2
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  • 7
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    Online Resource
    Post‐release monitoring of A ntillean manatees: an assessment of the B razilian rehabilitation and release programme
    Wiley ; 2016
    In:  Animal Conservation Vol. 19, No. 3 ( 2016-06), p. 235-246
    Details
    In: Animal Conservation, Wiley, Vol. 19, No. 3 ( 2016-06), p. 235-246
    Abstract: Mammalian reintroduction programmes frequently aim to reconnect isolated sub‐populations and restore population viability. However, these long‐term objectives are rarely evaluated due to the inadequacy of post‐release monitoring. Here, we report the results of a unique long‐term telemetry‐based monitoring programme for rehabilitated A ntillean manatees T richechus manatus manatus reintroduced into selected sites in north‐east B razil with the aim of reconnecting isolated relict populations. Twenty‐one satellite‐tagged rehabilitated manatees, 13 males and 8 females, were released into the wild from two sites between N ovember 2008 and J une 2013. Individual accumulation curves were plotted and home ranges were calculated through the fixed kernel method using 95% of the utilization distribution. The number and size of the centres of activity ( COAs ) were calculated using 50% of the utilization distribution. Manatees displayed a dichotomous pattern of movement, with individuals either characterized by sedentary habits or by much more extensive movements. Moreover, home‐range size was not significantly influenced by gender, age at release or release site. COAs were strongly associated with sheltered conditions within reefs and estuaries, and also by the presence of freshwater and feeding sites. Our data confirm that manatee reintroductions in B razil have the potential to reconnect distant sub‐populations. However, pre‐release identification of potential long‐distance migrants is currently unfeasible, and further analysis would be required to confirm genetic mixing of distant sub‐populations.
    Type of Medium: Online Resource
    ISSN: 1367-9430 , 1469-1795
    URL: Issue
    URL: Article
    DOI: 10.1111/acv.2016.19.issue-3
    DOI: 10.1111/acv.12236
    Language: English
    Publisher: Wiley
    Publication Date: 2016
    detail.hit.zdb_id: 1481960-0
    SSG: 12
    SSG: 23
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  • 8
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    Online Resource
    Breeding of White-tailed Tropicbirds (Phaethon lepturus) in the western South Atlantic
    FapUNIFESP (SciELO) ; 2016
    In:  Brazilian Journal of Biology Vol. 76, No. 3 ( 2016-04-19), p. 559-567
    Details
    In: Brazilian Journal of Biology, FapUNIFESP (SciELO), Vol. 76, No. 3 ( 2016-04-19), p. 559-567
    Abstract: Resumo Informações básicas sobre história natural são cruciais para acessar a viabilidade de populações, mas são ausentes para muitas espécies que necessitam de conservação. Uma destas espécies é o rabo-de-palha-de-bico-laranja, Phaethon lepturus Daudin, 1802. Aqui, vamos abordar o déficit de dados para esta espécie, fornecendo informações detalhadas sobre a biologia reprodutiva, tamanho da população, distribuição e ameaças em Fernando de Noronha, Brasil – a maior colônia de P. lepturus no Atlântico Sul. Acompanhamos a reprodução do rabo-de-palha-de-bico-laranja de Agosto de 2010 a Janeiro de 2011 monitorando ninhos e seus conteúdos. A estimativa da população foi obtida através de uma combinação de busca ativa de ninhos e censo no mar entre 2010 e 2012. O sucesso reprodutivo foi avaliado por métodos tradicionais. A curva de crescimento da coorte e a tabela de vida também foram obtidas. Além disso, informações sobre fidelidade ao ninho e parceiro e, a idade de reprodutores foi obtida a partir das aves anilhadas anteriormente. Nossos resultados indicam que a forma incomum de ninho (pináculos de calcário) e a predação por caranguejos podem ser responsáveis pelo sucesso observado de eclosão e recrutamento. A população de Fernando de Noronha parece estar estável entre 100-300 aves. No entanto, um programa de monitoramento a longo prazo seria desejável para avaliar as flutuações desta população globalmente importante. As estratégias de conservação devem se concentrar em controlar a predação por caranguejos e lagartos teiú.
    Type of Medium: Online Resource
    ISSN: 1678-4375 , 1519-6984
    URL: Article
    DOI: 10.1590/1519-6984.16514
    Language: Unknown
    Publisher: FapUNIFESP (SciELO)
    Publication Date: 2016
    detail.hit.zdb_id: 2159233-0
    SSG: 7,36
    SSG: 12
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  • 9
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    Online Resource
    Quantifying two‐dimensional dichromatic patterns using a photographic technique: case study on the shore crab ( Carcinus maenas L.)
    Wiley ; 2005
    In:  Ecological Research Vol. 20, No. 4 ( 2005-07), p. 497-501
    Details
    In: Ecological Research, Wiley, Vol. 20, No. 4 ( 2005-07), p. 497-501
    Abstract: Contrasting patterns of pigmentation, such as those associated with crypsis and aposematism, are common in many taxa. In order to determine why patterning varies among individuals or populations, it is important to quantify how these patches of pigment are arranged. Here we present a simple technique for measuring areas of pigmentation as well as their spatial distribution, and demonstrate its application to the study of substrate‐associated patterning in shore crabs ( Carcinus maenas L.). The results, based on a virtual grid laid over digital images of crab carapaces, allow for correlations to be made among sample populations. The technique, or variations of it, can be applied to any situation where two‐dimensional dichromatic patterns need to be quantified.
    Type of Medium: Online Resource
    ISSN: 0912-3814 , 1440-1703
    URL: Article
    DOI: 10.1007/s11284-004-0034-5
    Language: English
    Publisher: Wiley
    Publication Date: 2005
    detail.hit.zdb_id: 2023900-2
    SSG: 12
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  • 10
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    Online Resource
    Are Catfish (Ariidae) Effective Bioindicators for Pb, Cd, Hg, Cu and Zn?
    Springer Science and Business Media LLC ; 2012
    In:  Water, Air, & Soil Pollution Vol. 223, No. 7 ( 2012-9), p. 3911-3922
    Details
    In: Water, Air, & Soil Pollution, Springer Science and Business Media LLC, Vol. 223, No. 7 ( 2012-9), p. 3911-3922
    Type of Medium: Online Resource
    ISSN: 0049-6979 , 1573-2932
    URL: Article
    DOI: 10.1007/s11270-012-1160-2
    RVK:
    ZC 7520
    RVK:
    AR 10100
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2012
    detail.hit.zdb_id: 1479824-4
    detail.hit.zdb_id: 120499-3
    SSG: 12
    SSG: 13
    SSG: 21
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