Floods control the influence of environmental gradients on the diversity of zooplankton communities in a neotropical floodplain     

Nadson Ressyé Simões  Juliana Déo Dias  Clarice Maria Leal  Louizi de Souza Magalhães Braghin  Fábio Amodêo Lansac-Tôha  Cláudia Costa Bonecker 《Aquatic Sciences - Research Across Boundaries》2013,75(4):607-617

Floodplains show a high biodiversity due to their spatial heterogeneity and temporal variability, which are governed by environmental dynamics resulting from the flood pulse. We evaluated the importance of this driving force, the flood pulse, in the structuring of environmental gradients that influence species diversity in a neotropical floodplain. Gamma (γ) and alpha (α) zooplankton diversities were higher in the year with a typical flood pulse (2010), indicating that flood dynamics contributed to high diversity component values. We found significant relationships between α- and β-diversity and local environmental gradients, indicating that in years with a flood pulse, environmental filters might be the dominant mechanisms that structure the zooplankton community. Additive partitioning of γ-diversity showed that even in 2000 with atypical flood conditions, zooplankton diversities showed non-random patterns of spatial distribution and temporal variation in the floodplain. Our results indicate that the driving force of a floodplain can determine the spatial distribution of α- and β-diversity of aquatic communities owing to its primary effect on environmental filters. Therefore, if human activities that influence this driving force, such as water regulation, affect those environmental filters, floodplain biodiversity may decline.  相似文献   

Tourism Today: A Geographical Analysis by Douglas Pearce     

Juliana Mansvelt 《New Zealand geographer》1998,54(2):55a-56

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Evolution of the deep Atlantic water masses since the last glacial maximum based on a transient run of NCAR-CCSM3     

Juliana M. Marson  Lawrence A. Mysak  Mauricio M. Mata  Ilana Wainer 《Climate Dynamics》2016,46(3-4):865-877

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Trace metal distribution in white shrimp (<Emphasis Type="Italic">Litopenaeus schmitti</Emphasis>) tissues from a Brazilian coastal area     

Juliana Ribeiro Nascimento  Edison Dausacker Bidone  Denise Rolão-Araripe  Karina Annes Keunecke  Elisamara Sabadini-Santos 《Environmental Earth Sciences》2016,75(11):990

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Temporal variation and patchiness of zooplankton around a restored oyster reef     

Juliana M. Harding 《Estuaries and Coasts》2001,24(3):453-466

Zooplankton abundance and distribution patterns were determined for six seasonally important invertebrate taxa (bivalve veligers, gastropod veligers, polychaete larvae, barnacle nauplii, calanoid copepod adults and nauplii) and a diurnally important taxon (decapod zoea) around a restored oyster reef in the Piankatank River, Virginia. Data were collected on spatial scales of hundreds of meters and seasonal (May through October), diel (day-night), and tidal (3 h) temporal scales. Significant seasonal and diel patterns in abundance were observed for all taxa. Tidal influences alone appear to be less important than seasonal and diel patterns for most taxa but the interation of tidal and diel cues may have caused the observed diel zooplankton distribution patterns in both June and August 1996. Zooplankton taxa around the oyster reef were distributed non-randomly (patchily) regardless of their horizontal location with regard to the reef. Seasonal pulses in zooplankton abundance relate directly to life history patterns and reproductive cycles for individual taxa. Reef benthic fauna have the capacity to directly influence the composition and absolute abundance of the overlying zooplankton community and indirectly influence oyster reef community trophic dynamics.  相似文献   

Mapping urban risk: Flood hazards,race, & environmental justice in New York     

Juliana Maantay  Andrew Maroko 《Applied geography (Sevenoaks, England)》2009,29(1):111-124

This paper demonstrates the importance of disaggregating population data aggregated by census tracts or other units, for more realistic population distribution/location. A newly developed mapping method, the Cadastral-based Expert Dasymetric System (CEDS), calculates population in hyper-heterogeneous urban areas better than traditional mapping techniques. A case study estimating population potentially impacted by flood hazard in New York City compares the impacted population determined by CEDS with that derived by centroid-containment method and filtered areal-weighting interpolation. Compared to CEDS, 37% and 72% fewer people are estimated to be at risk from floods city-wide, using conventional areal weighting of census data, and centroid-containment selection, respectively. Undercounting of impacted population could have serious implications for emergency management and disaster planning. Ethnic/racial populations are also spatially disaggregated to determine any environmental justice impacts with flood risk. Minorities are disproportionately undercounted using traditional methods. Underestimating more vulnerable sub-populations impairs preparedness and relief efforts.  相似文献   

Long-term trends of polychlorinated biphenyls and chlorinated pesticides in franciscana dolphin (Pontoporia blainvillei) from Southern Brazil     

Juliana Leonel  Jose L. Sericano  Eduardo Secchi 《Marine pollution bulletin》2010,60(3):412-418

Selected POPs were analyzed in blubber samples of Pontoporia blainvillei from Southern Brazil to appraise temporal trend over a 10 year period (1994-2004). Overall, levels of POPs were relatively low, especially when compared to Northern Hemisphere concentrations. Apart from Mirex and PCBs, which showed stable concentrations, DDTs, HCB, CHLs, Dieldrin levels presented a slight decrease over the studied period. In addition, the increase in the PCBs/DDTs ratio supports the idea that inputs of DDTs are decaying faster than PCBs.  相似文献   

Erratum to: Quantifying and monetizing potential climate change policy impacts on terrestrial ecosystem carbon storage and wildfires in the United States     

David Mills  Russell Jones  Karen Carney  Alexis St. Juliana  Richard Ready  Allison Crimmins  Jeremy Martinich  Kate Shouse  Benjamin DeAngelo  Erwan Monier 《Climatic change》2015,131(1):179-181

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Changes in extreme daily rainfall for São Paulo, Brazil     

Maria A. F. Silva Dias  Juliana Dias  Leila M. V. Carvalho  Edmilson D. Freitas  Pedro L. Silva Dias 《Climatic change》2013,116(3-4):705-722

Significant positive trends are found in the evolution of daily rainfall extremes in the city of São Paulo (Brazil) from 1933 to 2010. Climatic indices including ENSO, PDO, NAO and the sea surface temperature at the coast near São Paulo explain 85 % of the increasing frequency of extremes during the dry season. During the wet season the climatic indices and the local sea surface temperature explain a smaller fraction of the total variance when compared to the dry season indicating that other factors such as the growth of the urban heat island and the role of air pollution in cloud microphysics need to be taken into account to explain the observed trends over the almost eight decades.  相似文献