Qualidade da operação na cultura da cana-de-açúcar utilizando cartas de controle

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

Prevendo mudanças climáticas: resposta da meiofauna a mudanças na distribuição espacial de espécies-chave

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Conforto térmico de edificações: análise crítica das tecnologias existentes

The rising in greenhouse gases emission as consequence of industrial expansion especially in developing countries is appointed as one of those reasons responsible for global warming. High-level temperatures are set as responsible for low productivity and high levels of discomfort. With the increase of worldwide energy demand, due to the population growth, this work aims to be an introductory text revising the current ventilation (mechanical and natural) and refrigeration technologies as well as low energy cooling techniques and architectural alternatives that seeks offering good ventilation and ideal buildings temperatures, making them sustainable. In addition, the text deals with the measurement instruments used to evaluate the parameters defined by international and national standards. At last, a case of study applies few concepts and technologies described in the text, introducing the results achieved, the limitations and suggestions to future works

Attenuation of ruminal methanogenesis

Ruminal methanogens reduce carbon dioxide to methane (CH 4 ), thereby preventing hydrogen use by bacteria for VFA synthesis resulting in a 2 to 12% loss in feed gross energy. Methane is a greenhouse gas that contributes to global warming. The objectives of this work were to determine: (1) the extent to which ruminal cultures acquire resistance to a nitrofuranyl derivative of para-aminobenzoate (NFP) and an extract from the plant Yucca shidigera (Yucca); (2) the effect of distillers dried grains plus solubles (DDGS) on ruminal CH4 production; (3) the effect of brome hay-based diets, corn-based diets, and in vivo 2-bromoethansulfonate treatment on ruminal methane (CH4 ) production; and (4) the effect of the above treatments on the methanogen population. Ruminal cultures treated with NFP for 90 d maintained a diminished capacity to generate CH4 , but cultures became resistant to the inhibitory effects of Yucca treatment within 10 d. Both treatments decreased (P < 0.01) the relative abundance of total Archaea and the order Methanomicrobiales, but Yucca treatment increased (P < 0.01) the relative abundance of the order Methanobacteriales. The replacement of brome hay and corn with DDGS in lamb diets decreased (P < 0.01) and increased (P < 0.05), respectively, the amount of CH4 produced per unit of digested DM. The substitution of DDGS for brome hay increased (P < 0.01) the relative abundance of the order Methanomicrobiales. The replacement of brome hay with corn decreased (P < 0.05) the amount of CH4 produced per unit of digested DM, and also decreased (P < 0.05) the relative abundance of both Archaea and the order Methanomicrobiales. However, the abundance of the order Methanobacteriales increased (P < 0.05) as corn replaced brome hay. Intraruminal administration of 2-bromoethansulfonate decreased (P < 0.05) CH4 emissions, and decreased (P < 0.05) the relative abundance of Archaea and Methanobacteriales. In conclusion, NFP may be efficacious for chronically inhibiting ruminal methanogenesis, and the replacement of dietary forage with DDGS attenuates CH4 emissions from ruminant animals. Changes in domain- and order-specific ribosomal DNA indicators of methanogens are not consistently correlated with changes in CH4 production.

Climate Change Policy: The Waxman-Markey Bill

The Waxman-Markey Bill is a comprehensive national climate and energy legislation designed to reduce global warming pollution and transition to a clean energy economy. In order to accomplish the first goal, the bill introduces a cap-and-trade program.

Conforto térmico de edificações: análise crítica das tecnologias existentes

The rising in greenhouse gases emission as consequence of industrial expansion especially in developing countries is appointed as one of those reasons responsible for global warming. High-level temperatures are set as responsible for low productivity and high levels of discomfort. With the increase of worldwide energy demand, due to the population growth, this work aims to be an introductory text revising the current ventilation (mechanical and natural) and refrigeration technologies as well as low energy cooling techniques and architectural alternatives that seeks offering good ventilation and ideal buildings temperatures, making them sustainable. In addition, the text deals with the measurement instruments used to evaluate the parameters defined by international and national standards. At last, a case of study applies few concepts and technologies described in the text, introducing the results achieved, the limitations and suggestions to future works

Revealing archaeal diversity patterns and methane fluxes in Admiralty Bay, King George Island, and their association to Brazilian Antarctic Station activities

The study of Antarctic archaeal communities adds information on the biogeography of this group and helps understanding the dynamics of biogenic methane production in such extreme habitats. Molecular methods were combined to methane flux determinations in Martel Inlet, Admiralty Bay, to assess archaeal diversity, to obtain information about contribution of the area to atmospheric methane budget and to detect possible interferences of the Antarctic Brazilian Station Comandante Ferraz (EACF) wastewater discharge on local archaeal communities and methane emissions. Methane fluxes in Martel Inlet ranged from 3.2 to 117.9 mu mol CH(4) m(-2) d(-1), with an average of 51.3 +/- 8.5 mu mol CH(4) m(-2) d(-1) and a median of 57.6 mu mol CH(4) m(-2)d(-1). However, three negative fluxes averaging -11.3 mu mol CH(4) m(-2) d(-1) were detected in MacKellar Inlet, indicating that Admiralty Bay can be either a source or sink of atmospheric methane. Denaturing gradient gel electrophoresis (DGGE) showed that archaeal communities at EACF varied with depth and formed a group separated from the reference sites. Granulometric analysis indicated that differences observed may be mostly related to sediment type. However, an influence of wastewater input could not be discarded, since higher methane fluxes were found at CF site. suggesting stimulation of local methanogenesis. DGGE profile of the wastewater sample grouped separated from all other samples, suggesting that methanogenesis stimulation may be due to changes in environmental conditions rather than to the input of allochtonous species from the wastewater. 16S ribosomal DNA clone libraries analysis showed that all wastewater sequences were related to known methanogenic groups belonging to the hydrogenotrophic genera Methanobacterium and Methanobrevibacter and the aceticlastic genus Methanosaeta. EACF and Botany Point sediment clone libraries retrieved only groups of uncultivated Archaea, with predominance of Crenarchaeota representatives (MCG, MG1, MBG-B, MBG-C and MHVG groups). Euryarchaeota sequences found were mostly related to the LDS and RC-V groups, but MBG-D and DHVE-5 were also present. No representatives of cultivated methanogenic groups were found, but coverage estimates suggest that a higher number of clones would have to be analyzed in order to cover the greater archaeal diversity of Martel Inlet sediment. Nevertheless, the analysis of the libraries revealed groups not commonly found by other authors in Antarctic habitats and also indicated the presence of groups of uncultivated archaea previously associated to methane rich environments or to the methane cycle. (C) 2010 Elsevier Ltd. All rights reserved.

An integrated stratigraphic record of the Palaeocene-lower Eocene at Gubbio (Italy): new insights into the early Palaeogene hyperthermals and carbon isotope excursions

Terra Nova, 24, 380386, 2012 Abstract A high-resolution, integrated stratigraphic framework (stable isotope stratigraphy, standard calcareous nannofossil and foraminiferal biostratigraphy, magnetostratigraphy) together with geochemical and rock magnetic properties analyses of a complete and well-preserved succession at Contessa Valley (Gubbio, central Italy) have offered an excellent opportunity to identify and constrain the Palaeocene to early Eocene hyperthermals and carbon isotope excursions (CIEs). In addition, we provide the first evidence in the Tethys Ocean of CIEs, previously identified in the Pacific, Atlantic and Southern Oceans, highlighting their global significance and of some unknown CIEs. Their characteristics are compared with those reported for deep-sea cores and other land-based sections to test whether the signature associated with CIEs documented in our composite section might give evidence for tracing them over wider areas. The Contessa composite section thus represents a reference succession also for insight into the magnetobiochronostratigraphy and the magnitude of early Palaeogene hyperthermals and CIEs.

Do Higher Temperatures Increase Growth in the Nocturnal Gecko Homonota darwini (Gekkota: Phyllodactylidae)? A Skeletochronological Assessment Analyzed at Temporal and Geographic Scales

Recent studies predict that several lineages of tropical animals are at particular risk given current estimates of global climate change. Yet, much uncertainty exists on the effects of climate shifts in ectothermic species from cool temperate regions such as Patagonia. In this study, we focus on the impact of environmental temperature on growth, age at sexual maturity, and life-span of the Patagonian gecko Homonota darwini. Skeletochronological methods were used to assess the bone growth rates Of individuals from three populations at different geographic and temporal scales: two populations from Chubut (warm site; 1941 and 2010) and one population from Rio Negro (cold site; 1997-1998). Populations displayed similar bone arrangement and the growth patterns fit a von Bertalanffy curve. Three populations attained reproductive size at a minimum age of 3 yr, but at the cold site two specimens were shown to mature in 4 yr. We found no differences in juvenile growth rates in body size or bone zone width between juveniles of 1 to 3 yr of age from the 1941 warm site and the 2010 warm site. However, these traits appeared to be higher at these two warm sites than at the cold site, which is consistent with the climatic differences among the three localities. Our results suggest that higher temperatures positively affect growth, denoting that global warming might benefit H. darwini, especially the southern populations.

Emission of Methane by Eudrilus eugeniae and Other Earthworms from Brazil

Earthworms emit denitrification-derived nitrous oxide and fermentation-derived molecular hydrogen. The present study demonstrated that the earthworm Eudrilus eugeniae, obtained in Brazil, emitted methane. Other worms displayed a lesser or no capacity to emit methane. Gene and transcript analyses of mcrA (encoding the alpha subunit of methyl-CoM reductase) in gut contents of E. eugeniae suggested that Methanosarcinaceae, Methanobacteriaceae, and Methanomicrobiaceae might be associated with this emission.

How far can we go in simplifying biomonitoring assessments? An integrated analysis of taxonomic surrogacy, taxonomic sufficiency and numerical resolution in a megadiverse region

The need for biodiversity conservation is increasing at a rate much faster than the acquisition of knowledge of biodiversity, such as descriptions of new species and mapping species distributions. As global changes are winning the race against the acquisition of knowledge, many researchers resort to the use of surrogate groups to aid in conservation decisions. Reductions in taxonomic and numerical resolution are also desirable, because they could allow more rapid the acquisition of knowledge while requiring less effort, if little important information is lost. In this study, we evaluated the congruence among 22 taxonomic groups sampled in a tropical forest in the Amazon basin. Our aim was to evaluate if any of these groups could be used as surrogates for the others in monitoring programs. We also evaluated if the taxonomic or numerical resolution of possible surrogates could be reduced without greatly reducing the overall congruence. Congruence among plant groups was high, whereas the congruence among most animal groups was very low, except for anurans in which congruence values were only slightly lower than for plants. Liana (Bignoniaceae) was the group with highest congruence, even using genera presence-absence data. The congruence among groups was related to environmental factors, specifically the clay and phosphorous contents of soil. Several groups showed strong spatial clumping, but this was unrelated to the congruence among groups. The high degree of congruence of lianas with the other groups suggests that it may be a reasonable surrogate group, mainly for the other plant groups analyzed, if soil data are not available. Although lianas are difficult to count and identify, the number of studies on the ecology of lianas is increasing. Most of these studies have concluded that lianas are increasing in abundance in tropical forests. In addition to the high congruence, lianas are worth monitoring in their own right because they are sensitive to global warming and the increasing frequency and severity of droughts in tropical regions. Our findings suggest that the use of data on surrogate groups with relatively low taxonomic and numerical resolutions can be a reliable shortcut for biodiversity assessments, especially in megadiverse areas with high rates of habitat conversion, where the lack of biodiversity knowledge is pervasive. (c) 2012 Elsevier Ltd. All rights reserved.

The impact of rising sea temperature on innate immune parameters in the tropical subtidal sea urchin Lytechinus variegatus and the intertidal sea urchin Echinometra lucunter

Ocean temperatures are rising throughout the world, making it necessary to evaluate the impact of these temperature changes on sea urchins, which are well-known bioindicators. This study evaluated the effect of an increase in temperature on the immune response of the subtidal Lytechinus variegatus and the intertidal Echinometra lucunter sea urchins. Both species were exposed to 20 (control), 25 and 30 °C temperatures for 24 h, 2, 7 and 14 days. Counting of coelomocytes and assays on the phagocytic response, adhesion and spreading of coelomocytes were performed. Red and colorless sphere cells were considered biomarkers for heat stress. Moreover, a significant decrease in the phagocytic indices and a decrease in both cell adhesion and cell spreading were observed at 25 and 30 °C for L. variegatus. For E. lucunter, the only alteration observed was for the cell proportions. This report shows how different species of sea urchins respond immunologically to rising temperatures

Human Abuses of Coral Reefs- Adaptive Responses and Regime Transitions

During the last few decades, coral reefs have become a disappearing feature of tropical marine environments, and those reefs that do remain are severely threatened. It is understood that humans have greately altered the environment under which these ecosystems previously have thrived and evoloved. Overharvesting of fish stocks, global warming and pollution are some of the most prominent threats, acting on coral reefs at several spatial and temporal scales. Presently, it is common that coral reefs have been degraded into alternative ecosystem regimes, such as macroalgae-dominated or sea urchin-barren. Although these ecosystems could potentially return to coral dominance in a long-term perspective, when considdering current conditions, it seems likely that they will persist in their degraded states. Thus, recovery of coral reefs cannot be taken for granted on a human timescale. Multiple stressors and disturbances, which are increasingly characteristic of coral reef environments today, are believed to act synergistically and produce ecological surprises. However, current knowledge of effects of compounded disturbances and stress is limited. Based on five papers, this thesis investigates the sublethal response of multiple stressors on coral physiology, as well as the effects of compounded stress and disturbance on coral reef structure and function. Adaptive responses to stress and disturbance in relation to prior experience are highlighted. The thesis further explores how inherent characteristics (traits) of corals and macroalgae may influence regime expression when faced with altered disturbance regimes, in particular overfishing, eutrophication, elevated temperature, and enhanced substrate availability. Finally, possibilities of affecting the resilience of macroalgae-dominaed reefs and shifting the community composition towards a coral-dominated regime are explored.

Biogenic habitat structure provided by temperate macroalgae change along a latitudinal gradient in ocean climate

[EN] Global warming is affecting all major ecosystems, including temperate reefs where canopy-forming seaweeds provide biogenic habitat. In contrast to the rapidly growing recognition of how climate affects the performance and distribution of individuals and populations, relatively little is known about possible links between climate and biogenic habitat structure. We examined the relationship between several ocean temperature characteristics, expressed on time-scales of days, months and years, on habitat patch characteristics on 24 subtidal temperate reefs along a latitudinal gradient (Western Australia; ca 34 to 27º S). Significant climate related variation in habitat structure was observed, even though the landscape cover of kelp and fucalean canopies did not change across the climate gradient: monospecific patches of kelp became increasingly dominant in warmer climates, at the expense of mixed kelp-fucalean canopies. The decline in mixed canopies was associated with an increase in the abundance of Sargassum spp., replacing a more diverse canopy assemblage of Scytothalia doryocarpa and several other large fucoids. There were no observed differences in the proportion of open gaps or gap characteristics. These habitat changes were closely related to patterns in minimum temperatures and temperature thresholds (days > 20 °C), presumably because temperate algae require cool periods for successful reproduction and recruitment (even if the adults can survive warmer temperatures). Although the observed habitat variation may appear subtle, similar structural differences have been linked to a range of effects on canopy-associated organisms through the provision of habitat and ecosystem engineering. Consequently, our study suggests that the magnitude of projected temperature increase is likely to cause changes in habitat structure and thereby indirectly affect numerous habitat-dependent plants and animals

Climatic and stratigraphic paleoindicators from the Canary Island

[EN] The last 5 Myr  are characterized by cliamatic variations globally and are reflected in ancient fossiliferous marine deposits visible in the Canary Islands. The fossils contained are identificated as paleoecological and paleoclimatic indicators. The Mio-Pliocene Transit is represented by the coral Siderastrea micoenica Osasco, 1897; the gastropods Rothpletzia rudista Simonelli, 1890; Ancilla glandiformis (Lamarck, 1822); Strombus coronatus Defrance, 1827 and Nerita emiliana Mayer, 1872 and the bivalve Gryphaea virleti Deshayes, 1832 as most characteristic fossils  and typical of a very warm climate and littoral zone. Associated  lava flows  have been dated radiometrically  and provides a range between  8.9 and about 4.2 Kyr. In the mid-Pleistocene, about 400,000 years ago, the called Marine Isotope Stage 11, a strong global warming that caused a sea level rise happens. Remains of the MIS 11  are preserved on the coast of Arucas (Gran Canaria), and associated with a tsunami in Piedra Alta (Lanzarote). These fossilifeorus  deposits contains the bivalve Saccostrea cucullata (Born, 1780), the gastropod Purpurellus gambiensis (Reeve, 1845) and the corals Madracis pharensis (Heller, 1868) and Dendrophyllia cornigera (Lamarck, 1816). Both sites have been dated by K-Ar on pillow lavas (approximately 420,000 years) and by Uranium Series on corals (about 481,000 years) respectively. The upper Pleistocene starts with another strong global warming known as the last interglacial or marine isotope  stage (MIS) 5.5, about 125,000 years ago, which also left marine  fossil deposits exposed in parallel to current in Igueste of San Andrés (Tenerife),  El Altillo, the  city of Las Palmas de Gran Canaria  and Maspalomas (Gran Canaria),  Matas Blancas, the Playitas and Morrojable (Fuerteventura ) and in Playa Blanca and Punta Penedo (Lanzarote ). The fossil coral Siderastrea radians (Pallas , 1766 ) currently living in the Cape Verde Islands , the Gulf of Guinea and the Caribbean has allowed Uranium series dating. The gastropods Strombus bubonius Lamarck, 1822 and Harpa doris (Röding , 1798 ) currently living in the Gulf of Guinea. Current biogeography using synoptic data obtained through satellites provided by the ISS Canary Seas provides data of Ocean Surface Temperature (SST) and Chlorophyll a (Chlor a) . This has allowed the estimation of these sea conditions during interglacials compared to today .