Padrão de frugivoria por Tapirus terrestris na Mata Atlântica do norte do Espírito Santo, Brasil

A anta Tapirus terrestris (Linnaeus, 1758), último representante da megafauna Pleistocênica na região Neotropical, representa um importante grupo funcional, pois se alimentam de uma grande variedade de espécies vegetais, especialmente frutos. No entanto, o padrão de frugivoria da espécie pode variar entre diferentes áreas. Dessa forma, nosso interesse foi investigar o grau de frugivoria da espécie em duas diferentes áreas no estado do Espírito Santo e a sua importância para a dinâmica florestal. Para isso, foram coletadas amostras fecais, através de busca ativa em diferentes ambientes na Reserva Biológica do Córrego do Veado (Rebio Córrego do Veado) e na Reserva Particular do Patrimônio Natural Recanto das Antas (RPPN Recanto das Antas), durante o período de janeiro de 2011 a novembro de 2013. Após a triagem do material biológico, as sementes foram individualizadas, classificadas quanto às características e grupos ecológicos e identificadas até o menor nível taxonômico possível. Foi obtido um esforço amostral de 130 dias, resultando em 325 amostras fecais coletadas, sendo 53,2% da Rebio Córrego do Veado e 46,8% da RPPN Recanto das Antas. Do total de amostras, 41,8% estavam depositadas dentro ou próximas a corpos dágua e 58,2% na serrapilheira/substrato seco. A dieta da anta foi composta por 94,1% de fibras e 5,9% de frutos. Foram encontradas duas vezes mais amostras contendo sementes na RPPN Recanto das Antas do que na Rebio Córrego do Veado. Das 30 morfoespécies encontradas nas amostras, 15 foram identificadas em nível específico, as quais estão distribuídas em oito famílias. As famílias mais representativas foram Anacardiaceae, Fabaceae e Myrtaceae. As espécies mais freqüentemente encontradas nas amostras foram Spondias macrocarpa Engl. e S. venulosa (Engl.) Engl. Do total de sementes encontradas 60% apresentam dispersão zoocórica e 46,7% são sementes grandes e muito grandes e 50% possuem fruto do tipo carnoso. Das morfoespécies encontradas, sete foram registradas em ambas as unidades de conservação, 21 foram encontradas apenas na RPPN Recanto das Antas e duas foram encontradas na Rebio Córrego do Veado. Isso pode indicar que o ambiente na RPPN Recanto das Antas pode fornecer mais frutos que na Rebio Córrego do Veado, o que pode ser um resultado do histórico de perturbações da última 8 reserva. Na década de 1980, 80% da Rebio Córrego do Veado foi queimada em um incêndio e, atualmente, o entorno da reserva é composto principalmente por pastagens. Ao contrário, a RPPN Recanto das Antas, apesar de sua área ter sofrido extração seletiva na década de 50, está inserida no maior remanescente de Mata Atlântica do Espírito Santo. Ainda que a anta possua uma dieta composta por uma variedade de frutos nas áreas de estudo, ela aparenta ser menos frugívora do que em outras áreas da Mata Atlântica. Contudo, é evidente a importância de T. terrestris na dispersão de um grande número de espécies vegetais, especialmente as espécies com sementes grandes, aumentando o recrutamento de espécies de plantas que não são dispersadas por outras espécies animais

Leaf Temperatures in a Gas Exchange Chamber and in the Open Air

Leaf temperatures in a Koch fully climatized gas-exchange chamber as designed by Siemens and in a similarly equipped open-air reference were measured with horizontally and vertically inserted thermocouples on Nerium oleander L. On a sunny day with only little air movement and an average air temperature of 20.4 °C, leaf over-temperatures in the gas-exchange chamber were lower on average by 2.2 K. The extent of reduction of over-temperature in the chamber is determined by the reduced global radiation in the chamber and the differences of wind velocities in chamber and reference. Differences in the ventilation intensity in the chamber have no demonstrable influence on the leaf over-temperatures. The over-temperatures of the reference leaves, on the other hand, depend to a large degree on air velocity. The changed radiation and air flow conditions in the chamber as compared with open-air conditions have consequences for the physiological reactions of the enclosed plant and must be taken into account when comparing results from gas-exchange measurements with open-air conditions. For further improvements of gas-exchange measurement equipment, air flow conditions and radiation quantity and quality might be starting point

Tightly Correlated HI and FUV Emission in the Outskirts of M83

We compare sensitive HI data from The HI Nearby Galaxy Survey (THINGS) and deep far UV (FUV) data from GALEX in the outer disk of M83. The FUV and HI maps show a stunning spatial correlation out to almost 4 optical radii (r25), roughly the extent of our maps. This underscores that HI traces the gas reservoir for outer disk star formation and it implies that massive (at least low level) star formation proceeds almost everywhere HI is observed. Whereas the average FUV intensity decreases steadily with increasing radius before leveling off at ~1.7 r25, the decline in HI surface density is more subtle. Low HI columns (<2 M_solar/pc^2) contribute most of the mass in the outer disk, which is not the case within r25. The time for star formation to consume the available HI, inferred from the ratio of HI to FUV intensity, rises with increasing radius before leveling off at ~100 Gyr, i.e., many Hubble times, near ~1.7 r25. Assuming the relatively short H2 depletion times observed in the inner parts of galaxies hold in outer disks, the conversion of HI into bound, molecular clouds seems to limit star formation in outer galaxy disks. The long consumption times suggest that most of the extended HI observed in M83 will not be consumed by in situ star formation. However, even these low star formation rates are enough to expect moderate chemical enrichment in a closed outer disk.Comment: Accepted for Publication in ApJ

GALEX and Optical Light Curves of EF Eridanus During a Low State: the Puzzling Source of UV Light

Low state optical photometry of EF Eri during an extended low accretion state combined with GALEX near and far UV time-resolved photometry reveals a source of UV flux that is much larger than the underlying 9500K white dwarf, and that is highly modulated on the orbital period. The near UV and optical light curves can be modeled with a 20,000K spot but no spot model can explain both the large amplitude FUV variations and the SED. The limitations of limb darkening, cyclotron and magnetic white dwarf models in explaining the observations are discussed.Comment: 10 pages, 4 figures to be published in ApJ Letter

The fate of spiral galaxies in clusters: The star formation history of the anemic Virgo cluster galaxy NGC 4569

We present a new method for studying the star formation history of late-type cluster galaxies undergoing gas starvation or a ram pressure stripping event by combining bidimensional multifrequency observations with multizone models of galactic chemical and spectrophotometric evolution. This method is applied to the Virgo Cluster anemic galaxy NGC 4569. We extract radial profiles from recently obtained UV GALEX images at 1530 and 2310 Å, from visible and near-IR narrow (Hα) and broadband images at different wavelengths (u, B, g, V, r, i, z, J, H, and K), from Spitzer IRAC and MIPS images, and from atomic and molecular gas maps. The model in the absence of interaction (characterized by its rotation velocity and spin parameter) is constrained by the unperturbed H-band light profile and by the Hα rotation curve. We can reconstruct the observed total gas radial density profile and the light surface brightness profiles at all wavelengths in a ram pressure stripping scenario by making simple assumptions about the gas removal process and the orbit of NGC 4569 inside the cluster. The observed profiles cannot be reproduced by simply stopping gas infall, thus mimicking starvation. Gas removal is required, which is more efficient in the outer disk, inducing radial quenching in the star formation activity, as observed and reproduced by the model. This observational result, consistent with theoretical predictions that a galaxy cluster-IGM interaction is able to modify structural disk parameters without gravitational perturbations, is discussed in the framework of the origin of lenticular galaxies in cluster

Synthetic Mudscapes: Human Interventions in Deltaic Land Building

In order to defend infrastructure, economy, and settlement in Southeast Louisiana, we must construct new land to mitigate increasing risk. Links between urban environments and economic drivers have constrained the dynamic delta landscape for generations, now threatening to undermine the ecological fitness of the entire region. Static methods of measuring, controlling, and valuing land fail in an environment that is constantly in flux; change and indeterminacy are denied by traditional inhabitation. Multiple land building practices reintroduce deltaic fluctuation and strategic deposition of fertile material to form the foundations of a multi-layered defence strategy. Manufactured marshlands reduce exposure to storm surge further inland. Virtual monitoring and communication networks inform design decisions and land use becomes determined by its ecological health. Mudscapes at the threshold of land and water place new value on former wastelands. The social, economic, and ecological evolution of the region are defended by an expanded web of growing land

Numerical Approximation of the Transport Equation: Comparison of Five Positive Definite Algorithms

IIASA's Regional Acidification INformation and Simulation (RAINS) model will be used to develop and assess international control strategies to reduce emissions of acidifying pollutants. These strategies will involve the expenditure of large sum of money; it is important, therefore, to assess the effect of uncertainties in the model on its results. An important component of the RAINS model is its atmospheric transport component; this paper reports the results of examining several algorithms for solution of the atmospheric transport equation. It also represents a joint effort between IIASA scientists and those in the Institute of Meteorology and Water Management in Warsaw and Central Institute for Meteorology and Geodynamics in Vienna

Thermal quark production in ultra-relativistic nuclear collisions

We calculate thermal production of u, d, s, c and b quarks in ultra-relativistic heavy ion collisions. The following processes are taken into account: thermal gluon decay (g to ibar i), gluon fusion (g g to ibar i), and quark-antiquark annihilation (jbar j to ibar i), where i and j represent quark species. We use the thermal quark masses, $m_i^2(T)\simeq m_i^2 + (2g^2/9)T^2$, in all the rates. At small mass ($m_i(T)<2T$), the production is largely dominated by the thermal gluon decay channel. We obtain numerical and analytic solutions of one-dimensional hydrodynamic expansion of an initially pure glue plasma. Our results show that even in a quite optimistic scenario, all quarks are far from chemical equilibrium throughout the expansion. Thermal production of light quarks (u, d and s) is nearly independent of species. Heavy quark (c and b) production is quite independent of the transition temperature and could serve as a very good probe of the initial temperature. Thermal quark production measurements could also be used to determine the gluon damping rate, or equivalently the magnetic mass.Comment: 14 pages (latex) plus 6 figures (uuencoded postscript files); CERN-TH.7038/9