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Effects of Macrophyte Functional Diversity on Taxonomic and Functional Diversity and Stability of Tropical Floodplain Fish Assemblages

Description: Multiple dimensions of biodiversity within and across producer and consumer guilds in the food web affect an ecosystem’s functionality and stability. Tropical and subtropical aquatic ecosystems, which are extremely diverse, have received much less attention than terrestrial ecosystems in regards to the effects of biodiversity on ecosystem functioning. We conducted a field experiment that tested for effects of macrophyte functional diversity on diversity and stability of associated fish assemblages in floodplain lakes of the Upper Paraná River floodplain, Brazil. Three levels of macrophyte functional diversity were maintained through time in five floodplain lakes and response variables included various components of fish taxonomic and functional diversity and stability. Components of functional diversity of fish assemblages were quantified using a suite of ecomorphological traits that relate to foraging and habitat use. Response variables primarily distinguished macrophyte treatments from the control. Macrophyte treatments had, on average, double the number of species and total abundance than the control treatment, but only limited effects on stability. The high diversity treatment was essentially nested within the low diversity for assemblage structure and had similar or even slightly lower levels of species richness and abundance in most cases. Gymnotiformes and young-of-year were diverse and relatively abundant in macrophyte treatments contributing to the large differences in diversity between macrophyte and control treatments. Higher fish diversity in structured habitats compared to more homogenous habitats is likely associated with increased ecomorphological diversity to exploit heterogeneous microhabitats and resources provided by the macrophytes.
Date: August 2015
Creator: Treviño, Jessica Marie
Partner: UNT Libraries

Brazil in Crisis

Description: This report examines the current political and economic climate in Brazil, which is in the midst of severe economic and political crises that are closely intertwined and unlikely to be resolved quickly.
Date: July 6, 2016
Creator: Meyer, Peter J.
Partner: UNT Libraries Government Documents Department

Reconnaissance for Radioactive Minerals in the Southern Part of Brazil

Description: From introduction: This report describes the results of reconnaissance for radioactivity of rocks, exclusive of coal, in the States of Rio de Janeiro, Sao Paulo, Parana, Santa Catarina and Rio Grande do Sul during the years 195 through 1956. Reports on reconnaissance and detailed studies of uraniferous coal are being prepared for publication. This report concerns work performed by the Brazilian National Nuclear Energy Commission and the United States Geological Survey (on behalf of the United States Atomic Energy Commission), and it is published with the permission of these agencies.
Date: January 1957
Creator: Pierson, Charles Thomas; Haynes, Donald D. & Ribeiro Filho, Evaristo
Partner: UNT Libraries Government Documents Department

Thresholds and Legacy Effects of Tropical Floodplain Fish Assemblages in Response to Flood Attributes

Description: Natural flow regimes are critical for sustaining biodiversity and river integrity. Floods and droughts form an important component of river systems and control population sizes and species diversity across space and time. Modification of flow regimes, including disruption of the timing, magnitude and duration of flooding, is a global problem, and many new impoundments are planned for large river-floodplain ecosystems in the tropics. Flow modifications may cause dramatic non-linear responses in population sizes and have lasting effects through time, but such topics are poorly investigated over multi-year scales, especially in highly diverse tropical ecosystems. Using a long-term dataset from the Upper Paraná River floodplain, Brazil, I tested for threshold and legacy effects of fish assemblages to flood attributes, such as timing, magnitude, duration, rate of change and variation. Specifically, I hypothesized that long duration, high magnitude floods would elicit threshold responses in long-distance migratory fish species and these responses result in significant legacy effects detectable over multiple years. Consistent positive threshold responses to increasing flood duration and magnitude were detected for many species and not significantly correlated with reproductive guilds. Legacy effects were prevalent (i.e. identified for more than 90% of species) and including flood attributes from previous years increased variance explained in species abundances by 15-20% compared to contemporary flood attributes alone. Contrary to my hypotheses, flood duration did not elicit strong legacy effects and species from the same reproductive guild did not have similar legacy effects models. The prevalence of legacy effects across almost all species in this diverse study system highlights the need to consider such dynamics in other systems. My results provide targets for management and conservation actions, such as environmental flow releases from upstream reservoirs. Environmental flows releases may play a significant role in sustainability of the floodplain and other tropical floodplain ecosystems affected by ...
Date: December 2015
Creator: Hoeinghaus, Ana Paula Ferrari
Partner: UNT Libraries

Brazil-U.S. Relations

Description: This report analyzes Brazil's political, economic, and social conditions, and how those conditions affect its role in the region and its relationship with the United States.
Date: June 3, 2009
Creator: Seelke, Clare Ribando & Meyer, Peter J.
Partner: UNT Libraries Government Documents Department

Brazil's WTO Case Against the U.S. Cotton Program: A Brief Overview

Description: On June 2, 2008, a World Trade Organization (WTO) Appellate Body (AB) publicly released its final report upholding a December 2007 compliance panel ruling that the United States has not fully complied with a March 2005 WTO ruling against certain U.S. cotton support programs. This AB ruling was part of a prolonged dispute settlement case (DS267) originated by Brazil against certain aspects of the U.S. cotton program in September 2002. This report provides a brief overview of Brazil's case against the U.S. cotton program, the evolution and current status of the case, and the potential role for Congress.
Date: June 17, 2008
Creator: Schnepf, Randy
Partner: UNT Libraries Government Documents Department

Reconnaissance for Uranium in the Coal of São Paulo, Santa Catarina, and Rio Grande do Sul, Brazil

Description: Abstract: Uranium-bearing coal and carbonaceous shale .of the Rio Bonito formation of Pennsylvanian age have been found in the States of Sao Paulo, Santa Catarina, and Rio Grande do Sul, Brazil. The uranium oxide content of the samples collected in the State of Sao Paulo ranges from 0.001 percent to 0.082 percent. The samples collected in Santa Catarina averaged about 0.002 percent uranium oxide; those collected in Rio Grande do Sul, about 0.003 percent uranium oxide. Since the field and laboratory investigations are still in their initial stages, only raw data on the radioactivity and uranium content of Brazilian coals are given in this report.
Date: January 1958
Creator: Haynes, Donald D.; Pierson, Charles T. & White, Max G.
Partner: UNT Libraries Government Documents Department

Sizing for the apparel industry using statistical analysis - a Brazilian case study

Description: Presented at the 2017 World Textile Conference. This paper presents results from a study of the body measurements of Brazilian women using the Kinect Body Imaging system for 3D body scanning to understand the need for accurate measurements in the apparel industry.
Date: May 2017
Creator: Capelassi, C. H.; Carvalho, M. A.; Kattel, C. El & Xu, Bugao
Partner: UNT College of Merchandising, Hospitality and Tourism

Brazil-U.S. Relations

Description: This report analyzes Brazil's political, economic, and social conditions, and discusses how those conditions affect its role in the region and its relationship with the United States.
Date: February 9, 2011
Creator: Meyer, Peter J.
Partner: UNT Libraries Government Documents Department

Brazilian Trade Policy and the United States

Description: As the largest and one of the most influential countries in Latin America, Brazil has emerged as a leading voice for developing countries in setting regional and multilateral trade agendas. Brazil is critical of U.S. trade policies such as the Byrd Amendment (repealed, but program in effect until October 1, 2007), which directs duties from trade remedy cases to affected industries, the administration of trade remedy rules, and what it considers to be discriminatory treatment in the U.S. expansion of free trade agreements in Latin America. Despite the differences, both countries recognize the potential for important gains to be had from mutually acceptable trade liberalization at all levels.
Date: February 3, 2006
Creator: Hornbeck, J. F.
Partner: UNT Libraries Government Documents Department

Brazil-U.S. Relations

Description: This report analyzes Brazil's political, economic, and social conditions, and how those conditions affect its role in the region and its relationship with the United States.
Date: March 5, 2010
Creator: Meyer, Peter J.
Partner: UNT Libraries Government Documents Department

Brazil-U.S. Relations

Description: This report analyzes Brazil's political, economic, and social conditions, and how those conditions affect its role in the region and its relationship with the United States.
Date: September 7, 2014
Creator: Meyer, Peter J.
Partner: UNT Libraries Government Documents Department

Brazil-U.S. Relations

Description: This report analyzes Brazil's political, economic, and social conditions, and how those conditions affect its role in the region and its relationship with the United States.
Date: August 18, 2009
Creator: Meyer, Peter J. & Seelke, Clare Ribando
Partner: UNT Libraries Government Documents Department

Brazil-U.S. Relations

Description: This report analyzes Brazil's political, economic, and social conditions, and how those conditions affect its role in the region and its relationship with the United States.
Date: October 6, 2008
Creator: Seelke, Clare Ribando & Durand, Alessandra
Partner: UNT Libraries Government Documents Department

Brazil-U.S. Relations

Description: This report analyzes Brazil's political, economic, and social conditions, and how those conditions affect its role in the region and its relationship with the United States. It then discusses a number of key issues in Brazil-U.S. relations.
Date: September 18, 2008
Creator: Seelke, Clare Ribando & Durand, Alessandra
Partner: UNT Libraries Government Documents Department

Rio+20: The United Nations Conference on Sustainable Development, June 2012

Description: This report discusses the purpose of the June 2012 United Nations (U.N.) Conference on Sustainable Development (UNCSD or “Rio+20”) in Rio de Janeiro, Brazil. It looks at issues that could be addressed during the conference as well as how this conference may differ from the last U.N. Conference on Environment and Development (UNCED) in Rio in 1992.
Date: June 18, 2012
Creator: Leggett, Jane A. & Carter, Nicole T.
Partner: UNT Libraries Government Documents Department