27 resultados para Forestry as an occupation.
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Activity profiles of excess Pb-210 combined with chemical data determined in two sediment cores from Corumbatai River basin, São Paulo State, Brazil, provided new insights into the reconstruction of historical inputs of anthropogenic constituents, contributing to improving management strategies of the hydrological resources in the basin since most of the municipalities extensively utilize the waters of Corumbatai River and tributaries for drinking purposes, among other uses. Excellent significant relationships between loss on ignition (LOI) and organic matter were found for sediments of both analyzed profiles. Silica was found to be inversely related to organic matter at both analyzed profiles: its decrease accompanied an increase in the specific surface of the sediments. This relationship was confirmed by a great number of inverse significant correlations among silica and oxides Na2O, K2O, CaO, MgO, Al2O3, P2O5, Fe2O3, MnO, and TiO2. It was possible to identify the role of organic matter on adsorption of several oxides/elements in the core sediments profiles. Apparent sediment mass accumulation rates corresponding to 224 and 802 mg cm(-2) year(-1) were obtained, and are compatible with field evidence, indicating a higher value associated with sand mining activities interfering with the natural/normal sedimentation process, due to modifications of the channel drainage.
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This work had as objective to quantify the reforestation for water retention in the Palmital Stream watershed, County of Jaboticabal, SP, by using the methodology of compensatory forestation for retention of water in watersheds. This methodology esteems the retention of water in watersheds considering the world medium value of destiny of the water in the hydrologic cycle, the use/occupation of the soil (forest, pasture and agriculture) and its permeability. The watershed in this study presents an area of 10,625.21 ha, being 237.75 ha at forest, 467.01 ha in pasture and 9,237.57 ha in agriculture. The medium values of the permeability identified in the soils were of 94.81 mm h -1 in forest, 8.99 mm t -1 in pasture and 36.01 mm h -1 in agriculture (sugar cane). Considering that should infiltrate in the soil 20.55% of the water that precipitates on the watershed, and, that the losses of water in forest areas is considered standard, the total estimated volume to compensate the excessive loss that occur in the areas of pasture and agriculture is 12.21 million of m 3ano. The compensatory forestation to retain that volume of loss should contemplate an area of 942.73 ha (8.87% of the area of the watershed). The reforestation can be priority in permanent conservation area or in areas of Legal Reserve.
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In Brazil, the degradation of soil and landscape by urban and agricultural frontiers expansion leads to the need for comprehensive studies and consider the diverse biological activities generated from different interventions in the landscape, becoming an instrument for assessing the impacts and the decision for its environmental management. The objective of this study was to evaluate the influence of different forms of occupation of the landscape, considering ecological elements and their interactions. The work was carried out on the Instituto Agronômico in the county of Jundiai, in the state of Sao Paulo, Brazil. The area under study has been subjected to different use and occupancy for a period of about 40 years. During this period the landscape has been transformed, with the current scenario can be classified as a degraded area mining; grassy area; Araucaria forest and pasture. These areas were evaluated by means of a transect, from which ten sampling sites were selected for the description of diverse biological activities, which included: evaluation and description of ground cover, identifying the presence of fungus and insect species. Furthermore, we evaluated in these points the pH, fertility and porosity of the topsoil (0-0.10 m). The results showed a variation of the elements analyzed and a relationship between the use and occupation of land in the different scenarios of the current landscape. The biological activity was more diverse in the Araucaria forest, reflected by the abundance of litter, higher content of organic matter and soil nutrients, demonstrating the effectiveness of the technique for assessing the level of degradation of the landscape used, which is expeditious and inexpensive.
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Decomposition of plant material influences soil aggregation dynamics in ways that are still poorly understood, especially for Oxisols, in which oxides are believed to play a dominant role. In an incubation experiment, we investigated (i) the effect of plant material addition from selected monocot and dicot species on soil organic C (SOC), carbohydrate composition, fungal and total microbial biomass, and aggregation of an Oxisol; and (ii) the relationship among these properties and C mineralization patterns. The experiment was carried out at 25 °C for 180 d after addition of 11 plant materials (4 g C kg-1 soil) and a control (no plant material added). Mineralization of C during the incubation was described considering two pools of C (labile and non-labile) using a first-order plus linear fitting. Compared to the control, corn materials showed larger pentose input, greater mineralization rates for the non-labile C pool (k), greater soil pentose content (xylose + arabinose) and larger mean weight diameter of soil water-stable aggregates at 180 d of incubation. These effects were independent of changes in SOC content, suggesting that total C accrual and macroaggregation may be decoupled processes in this Oxisol. Our results support the hypothesis that the non-labile plant C pool contributes to the long-lasting stability of macroaggregates of this Oxisol and that this effect is mediated by plant and soil pentoses. We propose that plant pentose content and the decomposition rate of the slow pool (k) are useful parameters for the prediction of plant effects on aggregation dynamics of Oxisols and the selection of soil conservation practices. © 2012.
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The evaluation of population characteristics, particularly those of endemic species, aids in population preservation and management. Hermit crabs present an innate behavior of occupying shells, which tends to individual needs and limits their distribution. This study characterized the pattern of occupation of gastropod shells by the hermit Loxopagurus loxochelis in three bays of the southwestern coast of Brazil. Monthly collections were made from January/1998 to December/1999 in the bays Ubatumirim (UBM), Ubatuba (UBA) and Mar Virado (MV) with a shrimping boat. Overall, ten species of gastropod shells were occupied by L. loxochelis. The shell of Olivancillaria urceus represented 66.8% of those occupied. Morphometric relationships demonstrated a differential occupation of the more abundant shells among demographic groups, where most of the males occupied O. urceus, non-ovigerous females occupied O. urceus and Buccinanops cochlidium, and ovigerous females occupied B. cochlidium and Stramonita haemastoma. Most of the individuals occupied the more abundant shells, considered adequate for the morphology of this hermit crab species. Thus, the studied bays seem to be stable and propitious environments for population perpetuation and the settlement of new individuals.
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In this article the social trajectory of a land occupation participant, an encamped woman (Edesmaria) who is a member of an extended landless family, is closely examined in order to demonstrate the inner workings of what is called 'the world of land occupations' in Brazil. Through a native expression (encampment time), it is demonstrated that nowadays, for some individuals, involvement in land occupations and landless workers' movements represents not just an opportunity to claim a parcel of land, but, even more importantly, a chance for social mobility and recognition. In this sense, encampment time is a social code and, as such, it not only quantifies the amount of time spent in a given encampment, but it is also a marker of prestige and status as well as a principle that organises and orders social relations in the land occupation world.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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At fixed bail stations in a large institutional setting in Brazil, the temporal and spatial pattern of usage of the dominant species of ant was studied. The ant Crematogaster cf. magnifica, was found in 91% of sampling points. These studies were conducted using the same points as a previous study of tile then dominant ant. Monomorium pharaonis, which was found to have declined from 93% to 3% spatial point occupation. The frequency of point usage during this study was significantly different from the Poisson distribution for both species, indicating non-random use of space. Crematogaster cf. magnifica was significantly more spatially exclusive than had been documented for M. pharaonis, and the probability of points originally occupied by M. pharaonis later becoming occupied by C. cf. magnifica was in excess of 90%. Temporal bait exploitation patterns of the two species did not differ. These data demonstrate that structural ant communities can change over time without human intervention, although short- term stability is characteristic of the urban dominant ants in subtropical Brazil.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Pós-graduação em Ciências Ambientais - Sorocaba
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Expansion of agricultural practice, cattle raising and forestry, in a disorderly way and no limits of land use, generates the degradation of natural resources such as soil, water and vegetation. That fact brings consequences, impacts the environment and the rural landscape. This study aimed to identify and quantify the land use in nine watersheds included in the watershed of Faxinal creek, located in western Botucatu, São Paulo State, Brazil, at 22º 51’ 35” and 22º 57’ 02” – Latitude S and 48º 39’ 42” and 48º 38’ 01” – Longitude W. The basin was subdivided into 9 subunits, being eight from second and one from third-order branch. The diagnosis of the subunits was carried out with geospatial technologies, in order to gather data on the use and occupation of the soil. Based on the obtained results, was concluded that the sub watersheds are occupied by the sum of areas of Citrus, horticulture, coffee plantation and small other occupations (25,81%), followed by reforestation (24,80%), as an isolated occupation element, has occupied the largest area.