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Estimativa da evapotranspiração no estado de São Paulo com o modelo da biosfera SiB2 / Evapotranspiration estimation in the State of São Paulo with SiB2 biosphere modelMartins, Cinthia Avellar 02 June 2011 (has links)
Utilizamos um modelo físico-matemático de relações biosfera-atmosfera para estimar a climatologia da evapotranspiração regional (ETR) entre 1980 e 2009 no estado de São Paulo, o modelo SiB2 (Simple Biosphere model). Os cálculos utilizaram dados horários da reanálise CFSR, por meio de etapas de comparação das forçantes com dados observados de superfície, e com dados de fluxos de superfície observados no campo. Os padrões da reanálise mostraram-se satisfatórios no domínio do estado de São Paulo para caracterizar a climatologia de chuva e temperatura da região, com pequenos vieses no ciclo diurno e no total anual de precipitação. Foram utilizados 6 cenários com cobertura de superfície homogênea em todo o estado (floresta de mata atlântica, cerrado, eucalipto, cana-de-açúcar, pastagem, urbanização), além de dois outros cenários (vegetação nativa e vegetação atual), que produziram médias de ETR substancialmente distintas. No cenário de eucalipto obteve-se a maior média anual, de 3,7 mm dia-1, seguido pelos valores calculados para floresta atlântica e vegetação nativa, próximos entre si, e com máximos valores do saldo de radiação e fração evaporativa. O impacto da mudança do uso da terra nos totais de ETR no estado de São Paulo pode ser discutido a partir do cenário de vegetação nativa, com ETR média de 3,3 mm dia-1, ~20% superior à ETR da vegetação atual. Obteve-se uma caracterização da climatologia da ETR real no estado de SP, com média de 930 mm ano-1, comparável com a climatologia do DAEE de 980 mm ano-1 no estado como um todo, e bem comparada com a ETR em várias sub-bacias hidrográficas. / We have used a biosphere-atmosphere relationships physical-mathematical model in order to estimate the regional evapotranspiration (ETR) climatology between 1980 and 2009, the SiB2 model (Simple Biosphere Model). The calculations used hourly data from CFSR reanalysis, through the steps of comparing forcing data with observed surface data, and with surface fluxes data observed in site. The reanalysis patterns proved satisfactory to characterize the climatology of rainfall and temperature in São Paulo state area, with small biases in the diurnal cycle and in total annual precipitation. Six homogeneous coverage surface scenarios throughout the state were used (Atlantic forest, brasilian savannah, eucalyptus, sugar cane, pasture, urbanization), and two other scenarios (native vegetation and nowadays vegetation), which produced substantially different mean ETR. The eucalyptus scenario obtained the highest annual average of 3.7 mm day-1, the greatest values were from eucalyptus, Atlantic forest and nowadays vegetation, close together, and with maximum values of net radiation and evaporative fraction. The land use change impact in the total ETR in São Paulo state can be discussed from the native vegetation scenario, with 3.3 mm day-1 average value, ~20% higher than nowadays vegetation. We obtained a characterization of real ETR climatology in São Paulo state, with an average of 930 mm year-1, comparable to DAEE climatology of 980 mm year-1 statewide, and well compared to ETR in various sub-basins.
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Microbiology and the limits to life in deep saltsPayler, Samuel Joseph January 2018 (has links)
Deep subsurface evaporites are common terrestrial deep subsurface environments found globally. These deposits are known to host communities of halophilic organisms, some of which have been suggested to be millions of years old. The discovery of evaporite minerals on Mars has led to these environments becoming of interest to astrobiology, particularly because the subsurface of Mars represents the best chance of finding more clement conditions conducive to life. Despite this interest, deep subsurface evaporites remain poorly understood and we have little insight into how different salts shape the Earth's biosphere, much of which is underground. This thesis addresses several knowledge gaps present in the literature by sampling a selection of brine seeps and rock salt samples taken from Boulby Potash Mine, UK. The origin and evolution of the brines is determined with geochemical techniques, showing the majority to have been sourced from an aquifer above where they were intersected in the mine. These brines appear to have taken a variety of pathways through the subsurface leading to the presence of a range of different ions dissolved within them. The majority are Na/Cl dominated, whilst one is K/Cl dominated. One brine appears to have a different origin and probably interacted with dolomite becoming very concentrated in Mg. This variety in brine origins and migration pathways has impacted the habitability of the brines. Physicochemical measurements for chaotropicity, water activity and ionic strength, combined with culturing experiments suggest brines from the Sherwood Sandstone were habitable, but the brine from a distinct unknown source was uninhabitable. DNA was successfully extracted from three of the habitable brines and their metagenomes sequenced. These revealed communities largely functionally and phylogenetically similar to surface near saturation brines, indicating that the structure of the communities present in saturated Na/Cl brines are controlled almost exclusively by these ions rather than any other environmental difference between the surface and subsurface. Organisms were also taken from these brines and culturing experiments carried out to determine if any carbon sources were present in ancient salt that might promote growth in the absence of other carbon sources. Controls showed that the geochemical changes to the growth media induced by solving the salts, particularly sylvinite, were responsible for the increases in growth observed, indicating certain salt minerals effectively fertilise the growth of halophiles. Culturing on hydrocarbon seeps collected in the mine suggested they may provide a carbon source periodically to some organisms within the deposit. Work was done to show the presence of dissimilatory sulphate and iron reducing halophiles. Overall this significantly advances our understanding of how salts shape the Earth's biosphere, particularly its deep subsurface component, and what functional capabilities life has to persist in these environments. This work provides a new window on the potential habitability of deep subsurface extraterrestrial environments and how we might go about investigating these environments for habitable conditions.
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Avian community structure and diversity in relation to coastal development in the Sian Ka’an Biosphere Reserve and Riviera Maya, Quintana Roo, MexicoRaymundo Sanchez, Angeles A 01 May 2010 (has links)
Habitat loss and fragmentation caused by tourist development along the eastern coast of the Yucatan Peninsula of Mexico represents a big threat to the survival of Nearctic-Neotropical migratory songbirds. This habitat plays a crucial role for successful migration for many migratory birds. However, the effects of habitat loss and fragmentation on these birds have not been well documented in the region. From September- December, 2006-2008, we mist-netted and conducted transect surveys to assess the variation in the avian community among three different levels of development (high, medium and low). The study area included two small reserves (10-20 ha) in the hotel zone associated with the Riviera Maya (high development), two sites with limited development within the Sian Ka’an Biosphere Reserve associated with small fishing camps (medium development), and two undeveloped sites located on a private ranch within Sian Ka’an (low development). I assessed species richness and abundance of four avian groups: the entire community, year-round residents, winter residents, and transients. Species richness and abundance decreased significantly with the greatest levels of disturbance. The high development level had the least species richness and abundance, whereas the medium development level had the greatest richness for all bird classes. However, my results suggest that small reserves in the hotel zone can be important compliments to the large, undisturbed reserves (Sian Ka’an) for both resident and migrant birds. Forty-six percent of all birds species captured in mist nets were Nearctic-Neotropical migrants; thus this group composed a significant component of the avian community. The dominance in the year-round resident community by the endemic Black Catbird (Dumetella glabrirostris) at medium and low development sites showed that coastal dune vegetation is also important in maintaining populations of endemic species, which are sensitive to levels of disturbance. The use of two different survey methods (mist-netting and transect surveys) produced complimentary descriptions of community composition. Because many year-round resident species and migrants depend on this scarce and discontinuous coastal habitat, and because of the intense development pressure on this coastal zone, better conservation strategies are needed to successfully sustain the avian community of this region.
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Evaluating ecotourism in Mexico’s biosphere reserves – whale watching activities in the World Heritage Site of Laguna San Ignacio, Baja California Sur, Mexico, 1994-2002Rossing, Peter 11 1900 (has links)
A descriptive case study approach and 34 indicators was used to examine the socio-economic impacts of whale watching tourism in the Laguna San Ignacio (LSI) World Heritage Site - located within the El Vizcaino Biosphere Reserve in Baja California Sur, Mexico. The framework measured both the socio-economic changes, and the economic viability of the local and regional operators. This approach led to a detailed understanding of the underlying, and often complex, inter-related factors that shaped the ecotourism development in LSI between 1994 and 2002. It identified strengths and weaknesses of current ecotourism development making it a valid tool for evaluating and improving these activities in any biosphere reserve.
More specifically the objectives were to examine:
1. How existing ecotourism operations and their activities in the LSI have changed since 1994;
2. Whether these changes have made ecotourism a more viable socio-economic development alternative for the local communities; and
3. Which strategies may be useful in overcoming identified barriers to further socio-economic benefits both from existing and future ecotourism activities.
The results strongly suggested that the benefits from ecotourism improved significantly between 1994 and 2002. Economically this was reflected in growth of visitor numbers (50%), employment (100%) and local and regional revenue approximately 70% (or 55% in real terms adjusting for inflation). Social benefits were seen in more cooperation among previous antagonistic stakeholders; a wider distribution of ecotourism benefits; some improvement in living standards and increasing local support for the Reserve. Politically, local stakeholders became more empowered through involvement in tourism related management activities. The viability of the local and regional operators also improved significantly as they became more sophisticated in their product offerings, enhanced their facilities and gained a market share of ecotourism relative to the foreign operators. These improvements were particular true for the operators that sold package tours. However, the analyses also revealed a number of barriers with the most important ones being:
• Unresolved historic land use conflicts over rights to land with ecotourism possibilities;
• Lack of activities diversification possibilities outside the tourism season;
• Stagnating visitor numbers;
• Uneven business skills among operators;
• Poor marketing and promotional efforts;
• Insufficient ecotourism infrastructure;
• A proposed ecotourism tax;
• Low profit margin of the ecotourism operators; and
• Lack of funding for further investments
To alleviate these threats and barriers 13 general strategies were identified. An elaboration of these resulted in 39 concrete operational strategies on how potentially to implement them.
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Public participation: rhetoric or reality? An analysis of planning and management in the Nanda Devi Biosphere ReserveSeaba, Natalie 30 January 2007 (has links)
Biosphere reserves have evolved out of a responsibility to resolve conflict by reconciling the needs of humans with the need to maintain ecological integrity and biodiversity. Participatory approaches to planning and management are seen as key to linking conservation and sustainable development. The purpose of this research was to investigate participation in planning and management activities in the Nanda Devi Biosphere Reserve (NDBR) located in Uttaranchal, India. Eco-development and microplanning have emerged in India as two government-initiated mechanisms allowing greater opportunity for other sectors to have a role in conservation-related planning and management activities.
Although there has been progress in the application of participatory processes, the two case studies in this research illustrate the need to bolster civic and private sector participation in planning and management of the NDBR. One important and positive outcome of the participatory processes that were applied was that relationships had improved between the sectors. / February 2007
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Avian community structure and diversity in relation to coastal development in the Sian Ka’an Biosphere Reserve and Riviera Maya, Quintana Roo, MexicoRaymundo Sanchez, Angeles A 01 May 2010 (has links)
Habitat loss and fragmentation caused by tourist development along the eastern coast of the Yucatan Peninsula of Mexico represents a big threat to the survival of Nearctic-Neotropical migratory songbirds. This habitat plays a crucial role for successful migration for many migratory birds. However, the effects of habitat loss and fragmentation on these birds have not been well documented in the region. From September- December, 2006-2008, we mist-netted and conducted transect surveys to assess the variation in the avian community among three different levels of development (high, medium and low). The study area included two small reserves (10-20 ha) in the hotel zone associated with the Riviera Maya (high development), two sites with limited development within the Sian Ka’an Biosphere Reserve associated with small fishing camps (medium development), and two undeveloped sites located on a private ranch within Sian Ka’an (low development). I assessed species richness and abundance of four avian groups: the entire community, year-round residents, winter residents, and transients. Species richness and abundance decreased significantly with the greatest levels of disturbance. The high development level had the least species richness and abundance, whereas the medium development level had the greatest richness for all bird classes. However, my results suggest that small reserves in the hotel zone can be important compliments to the large, undisturbed reserves (Sian Ka’an) for both resident and migrant birds. Forty-six percent of all birds species captured in mist nets were Nearctic-Neotropical migrants; thus this group composed a significant component of the avian community. The dominance in the year-round resident community by the endemic Black Catbird (Dumetella glabrirostris) at medium and low development sites showed that coastal dune vegetation is also important in maintaining populations of endemic species, which are sensitive to levels of disturbance. The use of two different survey methods (mist-netting and transect surveys) produced complimentary descriptions of community composition. Because many year-round resident species and migrants depend on this scarce and discontinuous coastal habitat, and because of the intense development pressure on this coastal zone, better conservation strategies are needed to successfully sustain the avian community of this region.
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Multidimensional Spatial Characterization of Plant Invasions in 'El Pinacate y Gran Desierto de Altar' Biosphere ReserveSanchez Flores, Erick. January 2006 (has links)
Invasive species are considered an agent of ecological change with more significant effects than global warming. Exotic plant invasions threaten biodiversity and ecosystem viability worldwide. Their effects in the Sonoran Desert ecosystems are a growing concern among ecologists and land managers. We hypothesized that highly dynamic desert environments are unstable, therefore more vulnerable to invasion by exotic plant species. To test this hypothesis we used a multidimensional approach to assess the spatial distribution of two exotic species: Brassica tournefortii (Saharan mustard) and Schismus arabicus (Arabian grass), in a portion of 'El Pinacate y Gran Desierto de Altar' Biosphere Reserve (PBR) in northwestern Sonora, Mexico. This approach combined genetic algorithms, geographic information systems, field methods, statistical analysis, and remote sensing modeling at multiple spatial and temporal scales to predict and test the current and potential distribution of the invasives over dynamic landscapes.Predicted probability of invasion was influenced strongly by human factors: Road networks were the strongest predictors of presence, revealing the potential importance of humans as vectors of invasiveness. Dynamic landscapes, associated mostly with vegetation losses, were detected spectrally in the eastern portion of the study area, very likely associated with past agricultural and current grazing activity. Combined models of high probability for invasion by B. tournefortii and S. arabicus over dynamic landscapes were tested against confirmed locations of the invasives and land cover types associated with invasion. Results confirmed the hypothesis of the study and suggest that more dynamic landscapes are more prone to invasion by these two exotic plants in the PBR. B. tournefortii was found associated mostly with landscapes occupied by microphyllous desert scrub and grassland, as well as sarcocaulescent desert scrub. S. arabicus was found more abundantly in the flat low lands occupied by microphyllous and crassicaulescent desert scrub. These relationships cannot, however, be conclusive and require further investigation due to the complex ecology of these invasives.
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Evaluating ecotourism in Mexico’s biosphere reserves – whale watching activities in the World Heritage Site of Laguna San Ignacio, Baja California Sur, Mexico, 1994-2002Rossing, Peter 11 1900 (has links)
A descriptive case study approach and 34 indicators was used to examine the socio-economic impacts of whale watching tourism in the Laguna San Ignacio (LSI) World Heritage Site - located within the El Vizcaino Biosphere Reserve in Baja California Sur, Mexico. The framework measured both the socio-economic changes, and the economic viability of the local and regional operators. This approach led to a detailed understanding of the underlying, and often complex, inter-related factors that shaped the ecotourism development in LSI between 1994 and 2002. It identified strengths and weaknesses of current ecotourism development making it a valid tool for evaluating and improving these activities in any biosphere reserve.
More specifically the objectives were to examine:
1. How existing ecotourism operations and their activities in the LSI have changed since 1994;
2. Whether these changes have made ecotourism a more viable socio-economic development alternative for the local communities; and
3. Which strategies may be useful in overcoming identified barriers to further socio-economic benefits both from existing and future ecotourism activities.
The results strongly suggested that the benefits from ecotourism improved significantly between 1994 and 2002. Economically this was reflected in growth of visitor numbers (50%), employment (100%) and local and regional revenue approximately 70% (or 55% in real terms adjusting for inflation). Social benefits were seen in more cooperation among previous antagonistic stakeholders; a wider distribution of ecotourism benefits; some improvement in living standards and increasing local support for the Reserve. Politically, local stakeholders became more empowered through involvement in tourism related management activities. The viability of the local and regional operators also improved significantly as they became more sophisticated in their product offerings, enhanced their facilities and gained a market share of ecotourism relative to the foreign operators. These improvements were particular true for the operators that sold package tours. However, the analyses also revealed a number of barriers with the most important ones being:
• Unresolved historic land use conflicts over rights to land with ecotourism possibilities;
• Lack of activities diversification possibilities outside the tourism season;
• Stagnating visitor numbers;
• Uneven business skills among operators;
• Poor marketing and promotional efforts;
• Insufficient ecotourism infrastructure;
• A proposed ecotourism tax;
• Low profit margin of the ecotourism operators; and
• Lack of funding for further investments
To alleviate these threats and barriers 13 general strategies were identified. An elaboration of these resulted in 39 concrete operational strategies on how potentially to implement them.
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Leaf area index in a tropical dry forest in MexicoHuang, Yingduan Unknown Date
No description available.
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Modeling change : a case study comparison of biosphere reserve governance in Canada and the United KingdomBoychuk, Elizabeth 15 November 2013 (has links)
Climate change is inevitable. The Intergovernmental Panel on Climate Change has forewarned the global community of the consequences of unrestrained burning of fossil fuels (Intergovernmental Panel on Climate Change [IPCC], 2011, para. 2). Until there is an economically viable source of alternative energy that can meet current and future demands, consumption of fossil fuels will continue to rise unless abated by models of governance that can assure sustainable use (Homer-Dixon & Garrison, 2010, p. 4). Climate change mitigation strategies take place in isolated cases where the resources and capability exist to address it. Biosphere reserves are governed as such. Each biosphere reserve has the ability to include climate change mitigation strategies within their mandates. Can these models of governance be used to demonstrate how to effectively address and mitigate climate change in other systems?
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