139 research outputs found
Flora da fazenda Nhumirim, Nhecolandia, Pantanal: relacao preliminar.
Com o objetivo de contribuir ao conhecimento da flora do Pantanal, ainda pouco conhecida, e para servir de base a estudos ecologicos fez-se a relacao preliminar da fazenda Nhumirim, considerada representativa da Nhecolandia em termos de solo (arenoso) e flora. As plantas arroladas pertencem a 606 especies, 377 generos e 116 familias. As familias mais numerosas sao: Gramineae (91 especies), Leguminosae (85), Compositae (28), Euphorbiaceae (26) e Cyperaceae (25). Os generos mais representados sao: Cassia (senso amplo), Paspalum, Panicum, Aeschynomene, Axonopus, Croton, Desmodium, Digitaria, Eleocharis, Eupatorium, Ludwigia, Polygala e Tabebuia. Cerca de 12% sao ruderais.bitstream/item/41132/1/PA05.pd
Dromion solutions of noncommutative Davey-Stewartson equations
We consider a noncommutative version of the Davey-Stewartson equations and
derive two families of quasideterminant solution via Darboux and binary Darboux
transformations. These solutions can be verified by direct substitution. We
then calculate the dromion solutions of the equations and obtain computer plots
in a noncommutative setting.Comment: 23 pages, 6 figure
Exploitation of Erythrina dominguezii Hassl. (Fabaceae)nectar by perching birds in a dry forest in western Brazil
Componente arbóreo, estrutura fitossociológica e relações ambientais em um remanescente de cerradão, em Curvelo - MG
Contribution of forest species to the floristic composition of a forested savanna in southeastern Brazil
Effect of environmental quality and mesohabitat structure on a Biotic Integrity Index based on fish assemblages of cerrado streams from Rio Cuiabá basin, Brazil
The role of protected areas in the avoidance of anthropogenic conversion in a high pressure region : a matching method analysis in the core region of the brazilian cerrado
Global efforts to avoid anthropogenic conversion of natural habitat rely heavily on the establishment of protected areas. Studies that evaluate the effectiveness of these areas with a focus on preserving the natural habitat define effectiveness as a measure of the influence of protected areas on total avoided conversion. Changes in the estimated effectiveness are related to local and regional differences, evaluation methods, restriction categories that include the protected areas, and other characteristics. The overall objective of this study
was to evaluate the effectiveness of protected areas to prevent the advance of the conversion of natural areas in the core region of the Brazil’s Cerrado Biome, taking into account the influence of the restriction degree, governmental sphere, time since the establishment of the protected area units, and the size of the area on the performance of protected areas. The evaluation was conducted using matching methods and took into account the following two fundamental issues: control of statistical biases caused by the influence of covariates on the likelihood of anthropogenic conversion and the non-randomness of the allocation of protected areas throughout the territory (spatial correlation effect) and the control of statistical bias caused by the influence of auto-correlation and leakage effect. Using a sample design that is not based on ways to control these biases may result in outcomes that underestimate or overestimate the effectiveness of those units. The matching method accounted for a bias reduction in 94–99% of the estimation of the average effect of protected areas on anthropogenic conversion and allowed us to obtain results with a reduced influence of the auto-correlation and leakage effects. Most protected areas had a positive influence on the maintenance of natural habitats, although wide variation in this effectiveness was dependent on the type, restriction, governmental sphere, size and age group of the unit
Neptune to the Common-wealth of England (1652): the republican Britannia and the continuity of interests
In the seventeenth century, John Kerrigan reminds us, “models of empire did not always turn on monarchy”. In this essay, I trace a vision of “Neptune’s empire” shared by royalists and republicans, binding English national interest to British overseas expansion. I take as my text a poem entitled “Neptune to the Common-wealth of England”, prefixed to Marchamont Nedham’s 1652 English translation of Mare Clausum (1635), John Selden’s response to Mare Liberum (1609) by Hugo Grotius. This minor work is read alongside some equally obscure and more familiar texts in order to point up the ways in which it speaks to persistent cultural and political interests. I trace the afterlife of this verse, its critical reception and its unique status as a fragment that exemplifies the crossover between colonial republic and imperial monarchy at a crucial moment in British history, a moment that, with Brexit, remains resonant
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