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MANEJO E MONITORAMENTO DE IMPACTOS SOBRE O ECOSSISTEMA EM ÁREAS PROTEGIDAS DE CERRADO: ESTRUTURA DA VEGETAÇÃO, GRAMÍNEAS EXÓTICAS E INCÊNDIOS - Tese de Doutorado pela UFGO

RESUMO: O uso de sensoriamento remoto e o avanço do conhecimento científico alavancaram a fitogeografia no mundo nas décadas passadas, ao aprofundarem o conhecimento sobre as fisionomias vegetais existentes e sua distribuição. Contudo, mapear as fitofisionomias das savanas ainda é particularmente complicado. Este trabalho investiga as dificuldades no mapeamento do Cerrado e as possibilidades de mapear suas classes de vegetação, ao mesmo tempo que produz um mapa de acurácia suficiente para monitorar as mudanças nessas classes. A alta variação de resposta espectral nas mesmas classes e ao longo dos anos ligada à dinâmica natural da vegetação – germinação de novos indivíduos, crescimento, floração, frutificação e senescência –, além da ocorrência de queimadas e do aspecto altamente segmentado e misturado da paisagem em função das classes de vegetação, geram grande heterogeneidade espacial e temporal da vegetação e se apresentam como os principais desafios para a classificação das formas vegetacionais do Cerrado. Foram utilizadas imagens Landsat 8, em um período de cinco anos a partir de 2013, e calculadas métricas baseadas em dezoito índices derivados de valores de reflectância das bandas dessas imagens, além dos valores de seis bandas. Dados amostrados em campo foram utilizados na classificação semiautomática para o mapeamento das classes de vegetação do Parque Nacional das Emas (PNE) e na validação do mapa gerado. A partir de um modelo replicável, foi possível elaborar um mapa com 89% de acurácia, superior a outros registros da literatura, e nove classes de fitofisionomias, diminuindo os custos e a subjetividade do trabalho manual de coleta de dados e correções a posteriori. Os dados apresentados na literatura até o momento apontam para ganhos em acurácia na discriminação dos objetos, em função da utilização de melhores métricas para medidas comparativas de resposta espectral e da melhor amostragem da variação temporal das respostas da vegetação.

PALAVRAS-CHAVE: Cerrado, fitofisionomias, sensoriamento remoto


ABSTRACT: The use of remote sensing and the advancement of scientific knowledge have leapfrogged phytogeography in the world in the past decades by expanding knowledge about existing plant physiognomies and their distribution. However, mapping the phytophysiognomies of the savannas is still particularly complicated. This work investigates the difficulties in mapping the Cerrado and the possibilities of mapping its vegetation classes, while at the same time producing a map of accuracy enough to monitor the changes in these vegetation classes. The high variation of spectral response in the same classes and over the years, linked to the natural dynamics of the vegetation – germination of new individuals, growth, flowering, fruiting and senescence – besides the occurrence of fires, the highly segmented and mixed aspect of the landscape in function of the vegetation classes, generate great spatial and temporal heterogeneity of the vegetation and are presented as the main challenges for the classification of vegetation forms of the Cerrado. For this were used Landsat 8 images relative to a period of 5 years from 2013 and were calculated metric sets based on 18 indices derived from reflectance values of the bands of these images in addition to the bands' own reflectance values. Data sampled in the field were used for semi-automatic classification for the mapping of the vegetation classes of the National Park of Emas (PNE). From a replicable model it was possible to elaborate a map with 89% accuracy, superior to other records in the literature, and nine classes of phytophysiognomies reducing the costs and the subjectivity of the manual work of data collection and a posteriori corrections. The data presented in the literature to date point to gains in accuracy in the discrimination of objects as a function of the use of better metrics for comparative means of spectral response and better sampling of the temporal variation of vegetation responses.

KEYWORDS: Cerrado, Vegetation Types, Remote Sensing.

Ano de Publicação: 2019

The human dimension of fire regimes on Earth

ABSTRACT

Humans and their ancestors are unique in being a fire-making species, but ‘natural’ (i.e. independent of humans) fires have an ancient, geological history on Earth. Natural fires have influenced biological evolution and global biogeochemical cycles, making fire integral to the functioning of some biomes. Globally, debate rages about the impact on ecosystems of prehistoric human-set fires, with views ranging from catastrophic to negligible. Understanding of the diversity of human fire regimes on Earth in the past, present and future remains rudimentary. It remains uncertain how humans have caused a departure from ‘natural’ background levels that vary with climate change. Available evidence shows that modern humans can increase or decrease background levels of natural fire activity by clearing forests, promoting grazing, dispersing plants, altering ignition patterns and actively suppressing fires, thereby causing substantial ecosystem changeand loss of biodiversity. Some of these contemporary fire regimes cause substantial economic disruptions owing to the destruction of infrastructure, degradation of ecosystem services, loss of life, and smoke-related health effects. These episodic disasters help frame negative public attitudes towards landscape fires, despite the need for burning to sustain some ecosystems. Greenhouse gas-inducewarming and changes in the hydrological cycle may increase the occurrence of large, severe fires, with potentially significant feedbacks to the Earth system. Improved understanding of human fire regimes demands: (1) better data on past and current human influences on fire regimes to enable global comparative analyses, (2) a greater understanding of different cultural traditions of landscape burning and their positive and negative social, economic and ecological effects, and (3) more realistic representations of anthropogenic fire in global vegetation and climate change models. We provide an historical framework to promote understanding of the development and diversification of fire regimes, covering the pre-human period, human domestication of fire, and the subsequent transition from subsistence agriculture to industrial economies. All of these phasestill occur on Earth, providing opportunities for comparative research.

Keywords Fire and culture, fire management, fire regime, global environmental changelandscape fire, palaeoecology, prehistoric human impacts, pyrogeography.

Ano de Publicação: 2011

Characterising fire spatial pattern interactions with climate and vegetation in Colombia

a b s t r a c t

Vegetation burning in tropical countries is a threat to the environment, causing not only local ecological, economic and social impacts, but also large-scale implications for global change. The burning is usually a result of interacting factors, such as climate, land-use and vegetation type. Satellite-derived monthly time series datasets of rainfall, burned area and active fire detections between December 2000 and 2009 were used in this study. A map of vegetation types was also used to determine these factors’ spatial and temporal variability and interactions with the total amount of burned area and active fires detected in Colombia. Grasslands represented the vegetation most affected by fires every year in terms of burnearea (standardised by their total area), followed by secondary vegetation, pasture and forests. Grasslands were also most affected by active fires, but followed closely by pasture, agricultural areas, secondary vegetation and forests. The results indicated strong climate and fire seasonality and marked regional difference, partly explained by climatic differences amongst regions and vegetation types, especially in the Orinoco and Caribbean regions. The incidence of fire in the Amazon and Andes was less influenceby climate in terms of burned area impacted, but the strength of the ENSO phenomenon affected the Orinoco and the Andes more in terms of burned area. Many of the active fires detected occurred in areas of transition between the submontane and lowland Andes and the Amazon, where extensive conversion to pasture is occurring. The possible high impact of small fires on the tropical rainforest present in this transition area and the Amazonian rainforest deserves more attention in Colombia due to its previous lack of attention to its contribution to global change.

Ano de Publicação: 2011

Fire and the spread of flowering plants in the Cretaceous

Summary

  • • We suggest that the spread of angiosperms in the Cretaceous was facilitated by novel fire regimes. Angiosperms were capable of high productivity and therefore accumulated flammable biomass (‘fuel’) more rapidly than their predecessors. They were capable of rapid reproduction, allowing populations to spread despite frequent disturbance.
  • • We evaluate the evidence for physical conditions conducive to fires in the Cretaceous. These included high temperatures, seasonally dry climate and higher atmospheric oxygen than current levels. We evaluate novel properties of angiosperms that contributed to rapid biomass accumulation, and to their ability to thrive in frequently disturbed environments. We also review direct evidence for Cretaceous fires.
  • • Charcoal mesofossils are common in Cretaceous deposits of the Northern Hemisphere. Inertinite, the charcoal component of coal, is common throughout the Cretaceous and into the Palaeocene, but declined steeply from the Eocene when angiosperm‐dominated forests became widespread.
  • • Direct and indirect evidence is consistent with angiosperms initiating novel fire regimes, promoting angiosperm spread in the Cretaceous. Several traits are consistent with frequent surface fires. We suggest that forest was slow to develop until the Eocene, when fire activity dropped to very low levels. The causes and consequences of fires in the deep past warrant greater attention.

Ano de Publicação: 2010

Subsides to the creation of a regional model of forest fire hazard: Taquari River Springs Park, MS—A case study

Abstract

Using map algebra, in the GIS (geographic information system) environment, this study integrates the B-RAMS, Brazilian Regional Atmospheric Models Software (CPTEC, 2005) climate model data with remote sensing data, intending to obtain a wildfire hazard map. The Taquari River Springs Park (TRSP) was chosen as a case study, due to the presence of springs which are considered important contributors to the Upper Paraguay River Basin, and it also contains essential remnants of the Cerrado Biome. The B-RAMS model has provided relative humidity, com ponents of the horizontal wind and temperature. The TRSP land cover was identified by object oriented classification of a LANDSAT ETM+ imagesupported by field observations. From the land cover phytophysionomic type characterization, a forest wildfire fuel map has been elaborated. The integration of the different maps has been made using a GIS, and a new map with its associateGIS database was generated showing the most vulnerable zones to wildfire hazard. 

Keywords: Forest fuel; Atmospheric modeling; Remote sensing; Map algebra

Ano de Publicação: 2007

Holocene fire and occupation in Amazonia: records from two lake districts

ABSTRACT

Abstract

While large-scale pre-Columbian human occupation and ecological disturbance have been demonstrated close to major Amazonian waterways, less is known of sites in terra firme settings. Palaeoecological analyses of two lake districts in central and western Amazonia reveal long histories of occupation and land use. At both locations, human activity was centred on one of the lakes, while the others were either lightly used or unused. These analyses indicate that the scale of human impacts in these terra firme settings is localized and probably strongly influenced by the presence of a permanent open-water body. Evidence is found of forest clearance and cultivation of maize and manioc. These data are directly relevant to the resilience of Amazonian conservation, as they do not support the contention that all of Amazonia is a ‘built landscape’ and therefore a product of past human land use.

Keywords: agriculture, charcoal, fossil pollen, Peru, Brazil, pre-Columbian

Ano de Publicação: 2007

Global distribution and seasonality of active fires as observed with the Terra and Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) sensors

We describe a new global multiyear satellite fire product designed to meet the needs of the global modeling community. We use the new data set to analyze the global distribution of biomass burning using five different temporal metrics derived from 5 years of high-quality satellite data acquired with the Moderate Resolution Imaging Spectroradiometer (MODIS), on board NASA’s Terra satellite. The global distributions of fire pixel density, peak month, season length, and annual periodicity are described. As part of our analysis we show, for the first time, the global distribution of the fire radiative power (FRP), a relatively new remotely sensed quantity. We find that low FRP tends to be associated with areas of cropland burning. In the tropics and much of the subtropics, low FRP is also associated with more heavily forested areas, while higher FRP tends to occur in areas of grassland burning. In boreal forests this trend is reversed, with higher FRP occurring in areas of greater tree cover. We next combine 3 years of Terra and Aqua MODIS observations to show that a strong diurnal fire cycle is prevalent at tropical and subtropical latitudes. We also consider the consistency of the fire time series recorded by the two MODIS instruments, and find the month of peak burning and fire season length observed by each to be in good agreement in most areas. However, significant discrepancies with respect to seasonality do occur in some relatively small areas, and are most pronounced in tropical rain forest.

Citation: Giglio, L., I. Csiszar, and C. O. Justice (2006), Global distribution and seasonality of active fires as observed with the Terra

and Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) sensors, J. Geophys. Res., 111, G02016,

doi:10.1029/2005JG000142.

Ano de Publicação: 2006

Mapeamento do uso e cobertura do Cerrado: Terraclass Cerrado 2013

Ano de Publicação: 2013

New records of Mesoclemmys raniceps (Testudines, Chelidae) for the states of Amazonas, Pará and Rondônia, North Brazil, including the Tocantins basin

Of the 58 species of living Chelidae (Rhodin et al., 2017), 20 are known from Brazil (Costa and Bérnils, 2018). Of these, nine occur in the Amazon basin, including species of the genera Chelus, Mesoclemmys, Platemys, Phrynops and Rhinemys (Ferrara et al., 2017). The genus Mesoclemmys is the most diverse in Brazil, and five of the eight species of Mesoclemmys in Brazil occur within the Amazon basin (Souza, 2005; Ferrara et al., 2017). Species of genus Mesoclemmys are rare and inconspicuous when compared to other freshwateturtles, and live in hard-to-reach places, to extent that populations are rarely studied. This genus represents the least studied among Amazonian turtles (Vogt, 2008; Ferrara et al., 2017).

Ano de Publicação: 2019

Avaliação do risco de extinção do jacaré-tinga Caiman crocodilus (Linnaeus, 1758) no Brasil

Apresentação e justificativa da categorização

O risco de extinção de Caiman crocodilus foi avaliado de acordo com os critérios da União Internacional para a Conservação da Natureza (IUCN 2001, 2003), com base nos dados disponíveis até 2011. A espécie habita praticamente todos os tipos de ambientes de zonas úmidas de baixa altitude na região Neotropical, sendo a espécie dentre os crocodilianos mais abundantee com maior distribuição na América Latina. É encontrado naturalmente do México até a região amazônica. Sua extensão de ocorrência (EOO) no território brasileiro é de 5.006.412,4 km2, podendo ser bem maior, caso as investigações sobre o status taxonômico da espécie confirmarea sua distribuição nas bacias dos rios Madeira, Mamoré e Guaporé. Acredita-se que sua área de ocupação (AOO) seja maior que 20.000 km2. É uma espécie extremamente adaptável, podendo ser encontrada em todos os habitats fluviais e lacustres presentes dentro de sua área de distribuição geográfica, e ocorre em grandes números ao longo da bacia amazônica e da bacia Tocantins- Araguaia, em especial em rios de água branca. Portanto, C. crocodilus foi categorizada como Menos Preocupante (LC). Ainda assim, a caça é uma forte ameaça para algumas subpopulações, sendo imprescindível a implementação de estudos de avaliação da efetividade do manejo sustentável como medida de conservação das populações naturais e diminuição do uso ilegal. Há conectividade com populações dos países vizinhos, porém não se sabe se há trocas significativas para justificar uma alteração na categoria indicada na avaliação brasileira. 

Rationale

Caiman crocodilus inhabits virtually all types of environments of low-lying wetlands in the Neotropics, being the most abundant species with largest distribution of all crocodilians in Latin America. Besides Brazil, C. crocodilus is found naturally in Colombia, Costa Rica, Ecuador, ESalvador, Guyana, French Guiana, Guatemala, Honduras, Mexico, Nicaragua, Panama, Peru, Suriname, Trinidad and Tobago and Venezuela. It was introduced in Cuba, Puerto Rico and the United States of America. In Brazil, it is distributed from the Amazon region to the plateau of Ibiapaba, Ceará. The extent of occurrence (EOO) calculated in the Brazilian territory, is 5,006,412.4 km2, however, may increase by an additional 479,749.2 km2, if studies of the taxonomic status of the species confirmed its distribution in the basins of the Madeira, Mamore and Guapore rivers (see attached map). It is believed that the area of occupancy (AOO) is greater than 20,000 km2.

Ano de Publicação: 2013