927 resultados para Burning of land
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Change in land cover is thought to be one of the key drivers of pollinator declines, and yet there is a dearth of studies exploring the relationships between historical changes in land cover and shifts in pollinator communities. Here, we explore, for the first time, land cover changes in England over more than 80 years, and relate them to concurrent shifts in bee and wasp species richness and community composition. Using historical data from 14 sites across four counties, we quantify the key land cover changes within and around these sites and estimate the changes in richness and composition of pollinators. Land cover changes within sites, as well as changes within a 1 km radius outside the sites, have significant effects on richness and composition of bee and wasp species, with changes in edge habitats between major land classes also having a key influence. Our results highlight not just the land cover changes that may be detrimental to pollinator communities, but also provide an insight into how increases in habitat diversity may benefit species diversity, and could thus help inform policy and practice for future land management.
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Climate change is projected to cause substantial alterations in vegetation distribution, but these have been given little attention in comparison to land-use in the Representative Concentration Pathway (RCP) scenarios. Here we assess the climate-induced land cover changes (CILCC) in the RCPs, and compare them to land-use land cover change (LULCC). To do this, we use an ensemble of simulations with and without LULCC in earth system model HadGEM2-ES for RCP2.6, RCP4.5 and RCP8.5. We find that climate change causes an expansion poleward of vegetation that affects more land area than LULCC in all of the RCPs considered here. The terrestrial carbon changes from CILCC are also larger than for LULCC. When considering only forest, the LULCC is larger, but the CILCC is highly variable with the overall radiative forcing of the scenario. The CILCC forest increase compensates 90% of the global anthropogenic deforestation by 2100 in RCP8.5, but just 3% in RCP2.6. Overall, bigger land cover changes tend to originate from LULCC in the shorter term or lower radiative forcing scenarios, and from CILCC in the longer term and higher radiative forcing scenarios. The extent to which CILCC could compensate for LULCC raises difficult questions regarding global forest and biodiversity offsetting, especially at different timescales. This research shows the importance of considering the relative size of CILCC to LULCC, especially with regard to the ecological effects of the different RCPs.
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The extensive use of land resources for food production, fibre for construction, wood pulp for paper, removal for extractive industries, sealing for urban and industrial development and as a receiver (either deliberate or accidental) of polluting substances has wrought huge changes in the chemistry, structure and biology of soils, away from their natural state.
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J.A. Ferreira Neto, E.C. Santos Junior, U. Fra Paleo, D. Miranda Barros, and M.C.O. Moreira. 2011. Optimal subdivision of land in agrarian reform projects: an analysis using genetic algorithms. Cien. Inv. Agr. 38(2): 169-178. The objective of this manuscript is to develop a new procedure to achieve optimal land subdivision using genetic algorithms (GA). The genetic algorithm was tested in the rural settlement of Veredas, located in Minas Gerais, Brazil. This implementation was based on the land aptitude and its productivity index. The sequence of tests in the study was carried out in two areas with eight different agricultural aptitude classes, including one area of 391.88 ha subdivided into 12 lots and another of 404.1763 ha subdivided into 14 lots. The effectiveness of the method was measured using the shunting line standard value of a parceled area lot`s productivity index. To evaluate each parameter, a sequence of 15 calculations was performed to record the best individual fitness average (MMI) found for each parameter variation. The best parameter combination found in testing and used to generate the new parceling with the GA was the following: 320 as the generation number, a population of 40 individuals, 0.8 mutation tax, and a 0.3 renewal tax. The solution generated rather homogeneous lots in terms of productive capacity.
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China Lake is located in Kennebec County, Maine. Since 1983 the lake has suffered from yearly algal blooms as a result of the addition of excess nutrients. The nutrient load was amplified by erosion within the watershed. Erosion varies widely depending on a number of factors, including the slope of the land, the type of soil, and the way the land is being used. Certain land use types have a high potential to add nutrients to the environment, while others may help absorb excess nutrients and prevent erosion and runoff into the lake. A comprehensive examination of the China Lake watershed was completed using GIS to calculate the erosion potential for the entire area, taking into account past and present land use patterns. This information will help the towns around the lake to make informed decisions about future development and land management.
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Os conflitos de uso são determinados pelas ocupações inadequadas do solo, como é o caso de ocupação do solo dentro de áreas de preservação permanente. O presente trabalho teve como objetivos determinar as classes de uso do solo e se há conflitos dentro de áreas de preservação permanente ao longo da rede de drenagem da microbacia do Ribeirão Água Fria, município de Bofete (SP). Situa-se geograficamente entre as coordenadas: 48°09'30 a 48°18'30 de longitude WGr., 22°58'30 a 23°04'30 de latitude sul com uma área de 15.242,84 ha. O mapa de uso do solo foi elaborado por meio da interpretação diretamente na tela do computador de imagem digital de satélite. Nos dados orbitais, a área de estudo está inserida no quadrante A, da imagem TM/Landsat-5, órbita 220, ponto 76, passagem de 8/09/2007. O Sistema de Informação Geográfica empregado foi o Cartalinx. As áreas de conflito da microbacia foram obtidas a partir do cruzamento entre os mapas de uso do solo e de APPs. Os resultados permitiram concluir que mais da metade da área (51,09%) está ocupada por pastagens, reflexo de solos arenosos e de baixa fertilidade. Constatou-se, ainda, que apesar de quase metade da microbacia estar coberta com algum tipo de vegetação (48,78% de mata natural/reflorestamento), possui aproximadamente um terço das áreas de preservação permanente utilizadas inadequadamente por pastagens (88,15%), reflorestamento (10,42%) e solo exposto (1,43%), totalizando 343,07 ha de áreas conflitantes em um total de 993,26 ha de APPs.
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In the Nilo Coelho irrigation scheme, Brazil, the natural vegetation has been replaced by irrigated agriculture, bringing importance for the quantification of the effects on the energy exchanges between the mixed vegetated surfaces and the lower atmosphere. Landsat satellite images and agro-meteorological stations from 1992 to 2011 were used together, for modelling these exchanges. Surface albedo (α0), NDVI and surface temperature (T0) were the basic remote sensing retrieving parameters necessary to calculate the latent heat flux (λE) and the surface resistance to evapotranspiration (rs) on a large scale. The daily net radiation (Rn) was obtained from α0, air temperature (Ta) and short-wave transmissivity (τsw) throughout the slob equation, allowing the quantification of the daily sensible heat flux (H) by residual in the energy balance equation. With a threshold value for rs, it was possible to separate the energy fluxes from crops and natural vegetation. The averaged fractions of Rn partitioned as H and λE, were in average 39 and 67%, respectively. It was observed an increase of the energy used for the evapotranspiration process inside irrigated areas from 51% in 1992 to 80% in 2011, with the ratio λE/Rn presenting an increase of 3 % per year. The tools and models applied in the current research, can subsidize the monitoring of the coupled climate and land use changes effects in irrigation perimeters, being valuable when aiming the sustainability of the irrigated agriculture in the future, avoiding conflicts among different water users. © 2012 SPIE.
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Includes bibliography
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This edition of the Bulletin presents a summary of topics examined and discussed during the Second Latin American Meeting of Bodies Responsible for the Supervision, Control and Regulation of Land Transport, held at ECLAC Headquarters, Santiago, Chile, from 10 to 12 August 1999. The rapporteur of the meeting was Mr. Humberto Valdés Ríos, Sub-Director, Asociación de Investigación y Producción del Transporte, Cuba.
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The first Latin American meeting of bodies responsible for the supervision, control and regulation of land transport, organized jointly by the Economic Commission for Latin America and the Caribbean (ECLAC) and the National Transport Regulation Commission of Argentina (CNRT), was held in Buenos Aires from 5 to 7 November 1997. Representatives of public- and private-sector bodies connected with land transport in Latin America, the United States of America and Europe took part in the meeting, in an atmosphere which was highly interactive owing to the numerous questions asked and the enriching discussions.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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The change detection technique was used in this study to provide preliminary information on the dynamics of land cover in the region over the western basin of the Tiete River. This area is characterized by sequence of reservoirs and intense agricultural activity, triggering series negative effects. One of the impacts is contamination and proliferation of aquatic organisms in these aquatics environments, increased by release of nutrients from human activities. This work was possible to observe a large switching classes and secondary vegetation bare land, probably related to agricultural activity.