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S. V. CUADRA M. H. COSTA C. J. KUCHARIK H. R. DA ROCHA J. D. TATSCH G. INMAN‐BAMBER R. P. DA ROCHA C. C. LEITE O. M. R. CABRAL 《Global Change Biology Bioenergy》2012,4(1):36-48
Scientists predict that global agricultural lands will expand over the next few decades due to increasing demands for food production and an exponential increase in crop‐based biofuel production. These changes in land use will greatly impact biogeochemical and biogeophysical cycles across the globe. It is therefore important to develop models that can accurately simulate the interactions between the atmosphere and important crops. In this study, we develop and validate a new process‐based sugarcane model (included as a module within the Agro‐IBIS dynamic agro‐ecosystem model) which can be applied at multiple spatial scales. At site level, the model systematically under/overestimated the daily sensible/latent heat flux (by ?10.5% and 14.8%, H and λE, respectively) when compared against the micrometeorological observations from southeast Brazil. The model underestimated ET (relative bias between ?10.1% and –12.5%) when compared against an agro‐meteorological field experiment from northeast Australia. At the regional level, the model accurately simulated average yield for the four largest mesoregions (clusters of municipalities) in the state of São Paulo, Brazil, over a period of 16 years, with a yield relative bias of ?0.68% to 1.08%. Finally, the simulated annual average sugarcane yield over 31 years for the state of Louisiana (US) had a low relative bias (?2.67%), but exhibited a lower interannual variability than the observed yields. 相似文献
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MARCELO DA COSTA SOUZA MARLI PIRES MORIM 《Botanical journal of the Linnean Society. Linnean Society of London》2008,158(2):306-308
A new species, Eugenia marambaiensis M.C.Souza & M.P.Morim, is described and illustrated. It is characterized by having large translucent gland dots densely distributed on the leaves, with a caudate apex and slightly wavy margins and a glabrous raceme, with only two flowers. Eugenia marambaiensis was only found in the locality of Restinga da Marambaia, Rio de Janeiro, Brazil. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 306–308. 相似文献
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MIGUEL MENEZES DE SEQUEIRA JORGE HENRIQUE CAPELO JOSÉ CARLOS COSTA ROBERTO JARDIM 《Botanical journal of the Linnean Society. Linnean Society of London》2008,156(4):639-647
The species formerly recognized as Teucrium scorodonia in Madeira is here described as new: Teucrium francoi M. Seq., Capelo, J.C. Costa & R. Jardim. Morphologically close to species of Teucrium gr. scorodonia [ T. scorodonia L., T. pseudoscorodonia Desf., T. siculum (Raf.) Guss. and T. kotschyanum Poech], it exhibits, nonetheless, some distinct diagnostic characters. The indumentum density and type of hairs of T. francoi are clearly distinct from those of related species, as are the shape and dimensions of the leaves and bracts, calyx, and corolla, which are all taken as taxonomically significant diagnostic features. A diagnosis and a distribution map are presented for this new species. Morphology, ecology, biogeography, and conservation issues are discussed. Teucrium francoi , which is an endemic from Madeira (Portugal), is to be found mostly in the scope of the association Teucrio francoi–Origanetum virentis J.C. Costa, Capelo, Jardim, Sequeira, Lousã & Rivas-Martínez, but also occurs in somewhat humid habitats, such as open stands of Rosa mandonii Déségl. associated with small streams. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 156 , 639–647. 相似文献
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M. L. CHAVES M. RIERADEVALL P. CHAINHO J. L. COSTA M. J. COSTA N. PRAT 《Freshwater Biology》2008,53(1):55-76
1. Macroinvertebrate assemblages of five non‐glacial intermittent high altitude headwater streams (above 1400 m – Serra da Estrela, Portugal), with dry periods of different lengths (0–3 months), were investigated in nearly undisturbed conditions to (i) examine spatial differences and identify environmental variables responsible for the observed invertebrate patterns, (ii) assess the association of dry period length with invertebrate community structure and (iii) determine the influence of using different taxonomic identification levels (order, family and genus) to assess invertebrate community patterns. 2. More than 100 macroinvertebrate genera were identified. Insects clearly dominated these communities with more than 95% of total captures and around 95% of the total richness. Diptera were the most rich and abundant group with chironomid occurrences comprising over 70% of macroinvertebrate captures. 3. The highest taxon richness, diversity, EPT (Ephemeroptera + Plecoptera + Trichoptera) and OCH (Odonata + Coleoptera + Heteroptera) genus richness, the greatest number of exclusive and characteristic taxa identified by the Indicator Value (IndVal), and a distinct community structure shown by Canonical Correspondence Analyses (CCA), were found in the only stream that was never totally dry, with pools lasting over summer. Environmental gradients that spatially structured the macroinvertebrate communities were always related to flow variations. 4. Over time, the highest abundances found in these systems were also related to flow variations and maximum genus richness occurred in the connected pools or in isolated pools. Streams with longer dry periods presented a distinct recolonization phase, with higher abundance of the stonefly larvae Nemoura sp. and the presence of the chironomid larvae Krenosmittia sp., possibly arriving from the hyporheos. 5. Taxonomic level of invertebrate identification was vital for recognizing the characteristic taxa (IndVal) of streams yet was not critical for identifying streams with the highest macroinvertebrate richness/diversity or structuring environmental gradients. 6. Overall, this study emphasizes the variability of high altitude intermittent streams macroinvertebrate communities, despite spatial proximity. This variability was probably related to flow intermittency and hydrologic permanence, different vegetation covers and riverbed substrata. Consequently, the establishment of reference conditions should involve long‐term data collections and more detailed physical characterization. Also, these findings have significant implications for accurately predicting the ecological consequences of future climate change in high altitude scenarios. 相似文献
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Reproductive and Foraging Energetics of High Latitude Penguins, Albatrosses and Pinnipeds: Implications for Life History Patterns 总被引:3,自引:0,他引:3
Pinnipeds and seabirds feed at sea, but are tied to shore torear their young. Such a fundamental life history constraintshould lead to convergent adaptations in foraging and reproductiveecology. However, intrinsic differences in mammalian and avianreproductive biology may limitthe potential for convergence.In this paper I examine both reproductive and foraging energeticsof pinnipeds and seabirds. This is done in an attempt to identifytraits that might be considered convergent adaptations to lifein the marine environment and to show how divergent life historypatterns are optimal for different reasons. From this analysiswe find that seabirds invest a greater total amount of energyand protein into the offspring than pinnipeds, but this comesat the cost of making more trips to sea. Whereas pinnipeds foragein a manner more consistent with the predictions of centralplace foraging theory and exhibit a greater ability to compensateto the shortened breeding season typical of high latitude environments. 相似文献
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