How can an invasive grass affect fire behavior in a tropical savanna? A community and individual plant level approach

Some invasive grasses have been reported to change fire behavior in invaded plant communities. Urochloa brizantha is an aggressive invasive grass in the Brazilian Cerrado, an ecosystem where fire is a common disturbance. We investigated the effects of U. brizantha on fire behavior in an open Cerrado physiognomy in Central Brazil. Using experimental burnings we compared fire behavior at both the community and the individual plant level in invaded (UJ) and non-invaded (NJ) areas burned in July. We also assessed the effect of fire season in invaded areas by comparing July (UJ) and October (UO) burnings. We evaluated the following variables: fuel load, fuel moisture, combustion efficiency, maximum fire temperature, flame height, and fire intensity. Additionally, we evaluated the temperatures reached under invasive and native grass tussocks in both seasons. Fuel load, combustion efficiency, and fire intensity were higher in NJ than in UJ, whilst flame height showed the opposite trend. Fuel amount and fire intensity were higher in October than in July. At the individual plant level, U. brizantha moisture was higher than that of native species, however, temperatures reaching ≥600 °C at ground level were more frequent under U. brizantha tussocks than under native grasses. At the community level, the invasive grass modified fire behavior towards lower intensity, lower burning efficiency, and higher flame height. These results provide essential information for the planning of prescribed burnings in invaded Cerrado areas.

Delineating zones to increase geographical detail in individual response data files: An application to the Spanish 2011 Census of population

Due to confidentiality considerations, the microdata available from the 2011 Spanish Census have been codified at a provincial (NUTS 3) level except when the municipal (LAU 2) population exceeds 20,000 inhabitants (a requirement that is met by less than 5% of all municipalities). For the remainder of the municipalities within a given province, information is only provided for their classification in wide population intervals. These limitations, hampering territorially-focused socio-economic analyses, and more specifically, those related to the labour market, are observed in many other countries. This article proposes and demonstrates an automatic procedure aimed at delineating a set of areas that meet such population requirements and that may be used to re-codify the geographic reference in these cases, thereby increasing the territorial detail at which individual information is available. The method aggregates municipalities into clusters based on the optimisation of a relevant objective function subject to a number of statistical constraints, and is implemented using evolutionary computation techniques. Clusters are defined to fit outer boundaries at the level of labour market areas.

Europe's economic challenges and the importance of ideas and innovation. CHALLENGE EUROPE Issue 22 - Challenges and new beginnings: Priorities for the EU's new leadership, September 2014.

How will we Europeans earn our living in 20 or 30 years' time? And how can it be done, while remaining true to our values of fairness, freedom and solidarity? These fundamental questions predate the financial crisis and will still be with us once we have fully overcome it. Of all the groups in society, business leaders are probably most keenly aware of the challenge posed by globalisation. They have their finger on the pulse of global economic activity and keep alerting me that Europe is losing out. The trade unions, generally more focused on the economy's demand side, regularly call for more (public) investment. Their leadership remains highly committed to Europe but they can sense a rise of Euro-scepticism among their members. We must, and can bring these two narratives together. Yes, global change is relentless and our societies must adapt, but we can also preserve what makes Europe such a special place: a unique combination of relative prosperity, solidarity, individual freedoms, and security. This challenge was always on my mind.

Using multiple landscape genetic approaches to test the validity of genetic clusters in a species characterized by an isolation-by-distance pattern

Bayesian clustering methods are typically used to identify barriers to gene flow, but they are prone to deduce artificial subdivisions in a study population characterized by an isolation-by-distance pattern (IbD). Here we analysed the landscape genetic structure of a population of wild boars (Sus scrofa) from south-western Germany. Two clustering methods inferred the presence of the same genetic discontinuity. However, the population in question was characterized by a strong IbD pattern. While landscape-resistance modelling failed to identify landscape features that influenced wild boar movement, partial Mantel tests and multiple regression of distance matrices (MRDMs) suggested that the empirically inferred clusters were separated by a genuine barrier. When simulating random lines bisecting the study area, 60% of the unique barriers represented, according to partial Mantel tests and MRDMs, significant obstacles to gene flow. By contrast, the random-lines simulation showed that the boundaries of the inferred empirical clusters corresponded to the most important genetic discontinuity in the study area. Given the degree of habitat fragmentation separating the two empirical partitions, it is likely that the clustering programs correctly identified a barrier to gene flow. The differing results between the work published here and other studies suggest that it will be very difficult to draw general conclusions about habitat permeability in wild boar from individual studies.

Desde el manicomio, 1920-22.

Poems.

Addresses and proceedings at the semi-centennial celebration of Middlebury College : held at Middlebury, Vermont, August 20, 21 and 22, 1850.

Cover title: Semi-centennial celebration of Middlebury College, MDCCCL.

Second International Conference of American States : Message from the President of the United States, transmitting a communication from the Secretary of State, submitting the report, with accompanying papers, of the delegates of the United States to the Second International Conference of American States, held at the City of Mexico from October 22, 1901, to January 22, 1902.

Mode of access: Internet.

Include sugar beets and sugarcane as basic commodities : hearing before the Committee on Agriculture, House of Representatives, Seventy-third Congress, second session, on H.R. 7907. February 19, 20, 21, 22, and 23, 1934.

"Serial J."

Law of the sea : hearing before the Subcommittee on Oceans and International Environment of the Committee on Foreign Relations, United States Senate, Ninety-fourth Congress, first session, on achievements of the Geneva session of the third United Nations Law of the Sea Conference, May 22, 1975.

Mode of access: Internet.

The Robert Vesco investigation : hearings before the Permanent Subcommittee on Investigations of the Committee on Government Operations, United States Senate, Ninety-third Congress, second session, pursuant to section 4, Senate resolution 46, 93d Congress, July 22, September 17, and October 7, 1974.

Mode of access: Internet.

Ley orgánica del Banco Hipotecario del Uruguay : Ley de 22 de octubre de 1915.

At head of title: República Oriental del Uruguay.

Actas, memorias y proyectos de las sesiones de la Habana : (segunda reunion del instituto) 22 a 27 de enero de 1917 ... /

At head of title: Instituto americano de derecho internacional.

Lake restoration : proceedings of a national conference, August 22-24, 1978, Minneapolis, Minnesota.

Mode of access: Internet.

Perspectives on nonpoint source pollution : proceedings of a national conference, Kansas City, Missouri, May 19-22, 1985.

Mode of access: Internet.

Protokoll über die Verhandlungen der Reichskonferenz der in der Binnenschiffahrt beschäftigten Maschinisten und Heizer : abgehalten zu Hamburg am 22. Dezember, 1912.

Mode of access: Internet.