16 research outputs found

    The potential of historical spy-satellite imagery to support research in ecology and conservation

    Get PDF
    Remote sensing data are important for assessing ecological change, but their value is often restricted by their limited temporal coverage. Major historical events that affected the environment, such as those associated with colonial history, World War II, or the Green Revolution are not captured by modern remote sensing. In the present article, we highlight the potential of globally available black-and-white satellite photographs to expand ecological and conservation assessments back to the 1960s and to illuminate ecological concepts such as shifting baselines, time-lag responses, and legacy effects. This historical satellite photography can be used to monitor ecosystem extent and structure, species’ populations and habitats, and human pressures on the environment. Even though the data were declassified decades ago, their use in ecology and conservation remains limited. But recent advances in image processing and analysis can now unlock this research resource. We encourage the use of this opportunity to address important ecological and conservation questions

    Climate change impacts on human health at an actionable scale: a state-level assessment of Indiana, USA

    Get PDF
    Climate change is already being felt on local levels, with historical records from the State of Indiana (USA) revealing warmer winters and more extreme precipitation events. To refine our understanding of climate change impacts on human health, we conducted a state-level assessment of future climate change impacts on human health using outputs from advanced climate model projections for this century. Future projections show a steep increase in extreme heat events, leading to greater potential vulnerability to heat disasters for Indiana communities. Additionally, a 2- to 4-fold increase in days with “uncomfortable night” conditions by the end of the century will strongly impact the cardiopulmonary health of more vulnerable populations (i.e., elderly, those with pre-existing conditions, children, and those with inadequate access to cooling). Continued trends for warmer winters and more flooding suggest a much greater risk for the expansion and virulence of a number of vector-borne diseases, such as Lyme disease, West Nile Virus, and “tropical” diseases for which the mosquito vectors will thrive. Higher temperatures will also drive more frequent and severe harmful algal blooms in lakes and reservoirs, with implications for human and animal health. Food systems will also be impacted, particularly with increased risk of contamination by bacteria and mycotoxins due to elevated heat and humidity

    Optical types of inland and coastal waters

    Get PDF
    Inland and coastal waterbodies are critical components of the global biosphere. Timely monitoring is necessary to enhance our understanding of their functions, the drivers impacting on these functions and to deliver more effective management. The ability to observe waterbodies from space has led to Earth observation (EO) becoming established as an important source of information on water quality and ecosystem condition. However, progress toward a globally valid EO approach is still largely hampered by inconsistences over temporally and spatially variable in-water optical conditions. In this study, a comprehensive dataset from more than 250 aquatic systems, representing a wide range of conditions, was analyzed in order to develop a typology of optical water types (OWTs) for inland and coastal waters. We introduce a novel approach for clustering in situ hyperspectral water reflectance measurements (n = 4045) from multiple sources based on a functional data analysis. The resulting classification algorithm identified 13 spectrally distinct clusters of measurements in inland waters, and a further nine clusters from the marine environment. The distinction and characterization of OWTs was supported by the availability of a wide range of coincident data on biogeochemical and inherent optical properties from inland waters. Phylogenetic trees based on the shapes of cluster means were constructed to identify similarities among the derived clusters with respect to spectral diversity. This typification provides a valuable framework for a globally applicable EO scheme and the design of future EO missions

    The climatic rhythm and blooms of cyanobacteria in a tropical reservoir in São Paulo, Brazil

    Full text link
    The present study sought to develop a methodology to analyse water quality based on the concepts and methods of climate and climatology. Accordingly, we attempted to relate hydro- and limnometeorological techniques and methodologies to a rhythmic analysis technique developed within the context of the Brazilian geographical climatology. Our goal was to assess and analyse cyanobacterial blooms, the main index of water quality for the reservoirs of the “Alto Tietê” Basin and, consequently, the Metropolitan Region of São Paulo, an area of high environmental complexity due to its high degree of development and high population density. The meteorological data used were collected by the Institute of Astronomy, Geophysics and Atmospheric Sciences at the University of São Paulo meteorological station, and the limnological data were collected through the Hydrological Monitoring System implemented by SABESP in the Billings and Guarapiranga Reservoirs and the laboratory of the same entity. The rhythmic and integrated analysis showed that the process of cyanobacterial blooms is dependent on a combination of meteorological factors as temperature and wind intensity that may disrupt the stability of the reservoir, providing the conditions necessary for the development of cyanobacteria during the stabilisation process. The pace of the Atlantic Polar Front Entrance during the winter in São Paulo is a limiting factor for the growth of cyanobacteria because of their high frequency, thus maintaining the balance of the reservoir throughout this period. The weather types those could cause a instability in the water column were: Cold Front entrance (66.67%), conflict between masses (22.22%) and the Tropical Instability Line (11.11%). The possibility for prevention and forecasting periods advise when these reservoirs should not be used, mainly with regard to recreational activities

    The climatic rhythm and blooms of cyanobacteria in a tropical reservoir in São Paulo, Brazil

    Full text link
    The present study sought to develop a methodology to analyse water quality based on the concepts and methods of climate and climatology. Accordingly, we attempted to relate hydro- and limnometeorological techniques and methodologies to a rhythmic analysis technique developed within the context of the Brazilian geographical climatology. Our goal was to assess and analyse cyanobacterial blooms, the main index of water quality for the reservoirs of the “Alto Tietê” Basin and, consequently, the Metropolitan Region of São Paulo, an area of high environmental complexity due to its high degree of development and high population density. The meteorological data used were collected by the Institute of Astronomy, Geophysics and Atmospheric Sciences at the University of São Paulo meteorological station, and the limnological data were collected through the Hydrological Monitoring System implemented by SABESP in the Billings and Guarapiranga Reservoirs and the laboratory of the same entity. The rhythmic and integrated analysis showed that the process of cyanobacterial blooms is dependent on a combination of meteorological factors as temperature and wind intensity that may disrupt the stability of the reservoir, providing the conditions necessary for the development of cyanobacteria during the stabilisation process. The pace of the Atlantic Polar Front Entrance during the winter in São Paulo is a limiting factor for the growth of cyanobacteria because of their high frequency, thus maintaining the balance of the reservoir throughout this period. The weather types those could cause a instability in the water column were: Cold Front entrance (66.67%), conflict between masses (22.22%) and the Tropical Instability Line (11.11%). The possibility for prevention and forecasting periods advise when these reservoirs should not be used, mainly with regard to recreational activities.O presente trabalho buscou desenvolver uma metodologia para análise da qualidade da água com base em conceitos e métodos do clima e da climatologia respectivamente. Dessa forma, buscou-se relacionar técnicas e metodologias hidrometeorológicas e limno-meteorológicas com a técnica de análise rítmica desenvolvida dentro da climatologia geográfica brasileira para avaliar e analisar as florações de cianobactérias, principal índice de qualidade de água encontrado nos reservatórios da Bacia do Alto Tietê e consequentemente da Região Metropolitana de São Paulo, área de alta complexidade ambiental devido ao seu alto grau de desenvolvimento e a sua alta densidade populacional. Os dados meteorológicos utilizados para o desenvolvimento do trabalho foram coletados a partir da estação meteorológica do Instituto de Astronomia, Geofísica e Ciências Atmosféricas da Universidade de São Paulo e os dados limnológicos foram coletados por meio do Sistema de Monitoramento Hidrológico implantado pela SABESP nos reservatórios de Billings e Guarapiranga assim como os dados laboratoriais da mesma entidade. A análise rítmica e integrada de todos os dados mostrou que o processo de floração de cianobactérias é dependente não apenas de um fator específico, mas de uma combinação de fatores meteorológicos como temperatura e intensidade do vento que podem quebrar a estabilidade do reservatório e proporcionar durante a estabilização as condições necessárias para o desenvolvimento das cianobactérias. Também foi mostrado como o ritmo de entrada de Frentes Polares Atlânticas, durante o inverno paulistano, é um fator que limita o crescimento das cianobactérias devido à sua alta frequência, mantendo o reservatório desequilibrado por todo o período. Os tipos de tempo que podem causar instabilidade na coluna da água foram identificados com: entrada de Frentes Frias (66,67%), conflitos entre massas (22,22%) e Linha de Instabilidade (11,11%). Mostra-se assim a importância do trabalho para a prevenção e previsão de períodos inapropriados para o uso desses reservatórios principalmente para atividade de recreação.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

    Effects of atmospheric cold fronts on stratification and water quality of a tropical reservoir: implications for aquaculture.

    Get PDF
    Stratification and mixing patterns of a water body are influenced by the variability of atmospheric systems, which can also modify their biogeochemical properties. The primary goal of this study was to analyze the effect of atmospheric cold fronts (CFs) on thermal stratification and water quality parameters in 4 embayments of the Furnas Hydroelectric Reservoir (FHR) (southeastern Brazil), a warm monomictic water body. A secondary goal was to evaluate the implications of this effect on the aquaculture of Nile tilapia Oreochromis niloticus (L.) in net cages. A 2 yr dataset of meteorological and water quality parameters was used to compute heat flux balance components and buoyancy frequency. These parameters were used to evaluate the influence of CFs on FHR water column stability and water quality. It was observed that the passing of CFs increased net heat loss and wind velocity, resulting in a partial mixture of surface waters with deeper layers. These changes in the physical structure of the water column altered the diel cycle of water temperature, led to a slight decrease in dissolved oxygen concentrations and pH values during the stratification period, and contributed to the increase in dilution power at the fish cultivation sites. However, following CF passages, no significant changes were observed in water quality parameters that influenced Nile tilapia cultivation in the FHR. Nevertheless, the understanding of meteorological systems and their influence on the physical and biogeochemical properties of an aquatic system is important for optimal management of aquaculture activities.Made available in DSpace on 2017-12-12T23:33:36Z (GMT). No. of bitstreams: 1 2017AP37.pdf: 6890847 bytes, checksum: 8980d6773f9980f037a238aa6efeea20 (MD5) Previous issue date: 2017-12-12bitstream/item/168748/1/2017AP37.pd
    corecore