5 resultados para River micro-basin
em Universidade Federal do Rio Grande do Norte(UFRN)
Resumo:
In the contemporary world to the deterioration of semi-arid areas of the planet has been the focus of media attention and the scientific community. Brazil has a semiarid, considered the most problematic of the world, either by pressure from physical factors, whether as a result of misguided public policies, has over time been suffering from the consequences of a deterioration that expands over the years. Methodologies, that amidst the problems of semi-arid, come against the deteriorating local, have a good chance to be reapplied in other contexts around the world. This research, based on methodological model for analyzing environmental deterioration, introduced and examined the applicability of the methodology in the semi-arid region of Rio Grande do Norte - Brazil. Although the results provide guidelines for the introduction of underground dams, the application of the methodology was ineffective, given the high rates of forest cover that gave low values for the physical diagnosis conservationist
Resumo:
The fissures aquifer northeast semi-arid Brazilian, present high text frequently of leave, with of low a hídric availability. The research has as objective main to analyze the components that inside influence in the salinity of the waterbearing fissures of an evaluation physicist-chemistry of the water, leading in consideration the physical interventions of the environment. One used techniques of interpretation of image of Landsat satellite -1999 and delimitation of the micro basin through the topographical map SUDENE. One identified waters of the NaCl type with Ca++ and Mg++ in secondary concentrations. The analyzed wells (15), had presented an average salinity of 5.147 mg/L of STD and a well only supplies drinking waters with 319 mg/L of STD. The recharge of the aquifer one if carries through for infiltration in the open fracture of ortognaisse it migmatization. The type and directions of the fracture do not control the STD. Relations between salinity and out let do not exist. The quality of the well of low salinity is identical the superficial waters (aquifer dam and alluvial). The studies of the meteoric erosion processes had evidenced that in the transformations of the rock in ground, the Ca++ and Na+ are taken for superficial waters. The treatment of the data chemical showed that the grade of Na+, Ca++, Mg++ and Cl-are controlled for the evaporation process, from only water that would have the qualities of superficial waters or the well of low salinity. Already the HCO3-grade is controlled for the precipitation of the dolomite. The STD of this aquifer one would be consequence of the high tax of evaporation of dams constructed in regions of plain topography. You leave them precipitated in deep argillaceous ones dry dams are led for the aquifer in first rains. The research suggests some recommendations for the use and exploitation of the water salinity in piscicultura, carcinicultura, culture of the grass-salt (Atriplex sp), among others
Resumo:
During the dry and rainy periods, in the Piranhas-Assu river hydrographic basin, variations in bacterioplankton and trophic state indexes were studied in the lotic and lentic environments. The means of total bacterial density wavered in the order of 107 organisms. mL-1 and they were higher in the rainy period. Cocci bacteria were numerically predominant in all sampling points, influencing the total abundance of bacterioplankton. Total bacterial biomass varied from 659 to 1997,3 µgC.L-1 due to the high values of filaments cellular volume. Total phosphorus amounted 108 µg.L-1 and it had a positive correlation with chlorophyll a (r = 0,94; p < 0,05) during dry period, when these variables presented higher concentrations. There wasn t a high spatial variation. The low transparency of water and the phosphorus and chlorophyll concentrations indicated eutrophic or hipereutrophic levels in studied points of reservoir. These variables, associated with high density and biomass values found, alert to the necessity of a constant monitoring of the semi-arid aquatic ecosystems, where the quality of water is affected by dry occurrence
Resumo:
To contribute in the performance of policies and strategies formulated by development agencies, indexes have been created in anticipation of expressing the multiple dimensions of water resources in an easily interpretable form. Use of Hydro Poverty Index ( WPI) is spreading worldwide , with the same formed by the combination of sub - indices Resource, access, capacity , use and environment. S ome critics a s to its formation have emerged, a mong them stands out the allo cation of weights of sub - indexes , made by an arbitrary process attributing subjectivity to the selection criteria. By involving statistical analysis, when considering the characteristics of the variables generated by the Principal Component Analysis (PCA), it turns out that it is able to solve this problem. The objective of this study is to compare the results of the original WPI with content generated by Principal Com ponent Analysis (PCA) for the indicati on of the weights of sub - indec es applicable in the Seridó River hydrographic Basin . We conclude that the use of Principal Component Analysis in the allocation of weights of Water Poverty Index has identified the sub - indices Resources, Access and Environment are the most representative for the river basin Seridó , and that this new index, WPI' , presented the most comprehensive ranges of values , allowing more easily identify disparities among municipalities. In addition, t he evaluation of the sub - indec es in the study area has great potential to inform the decision - maker in the management of water resources, the most critical locations and deserve greater investments in the aspects analyzed, as the index itself can not cap ture this information.
Resumo:
Hydrographic basins always exercised a big fascination over humankind that attracted for its scenery beauty or for its richness in natural resources, had been acting in order to modify these important ecosystems without, therefore, considering the possible consequences of these changes. The attributed importance to the coast ecosystems, in eminence to the hydrographic basin of Punaú river and adjacent areas, is had when it s verified the diversity of the ecosystems that contemplate it. Hydrographic basin in evidence in Rio Grande do Norte state, occupies an area of nearly 652.71 km², being it sited in the homogeneous micro-region Litoral Nordeste, with a regional population estimated in nearly 75,188 inhabitants, according to the Anuário Estatístico do Rio Grande do Norte 2004. The region of the researched basin is formed by seven municipal districts related as it follows: Maxaranguape, Pedra Grande, Pureza, Rio do Fogo, São Miguel de Touros, Taipu and Touros, but Maxaranguape, Rio do Fogo, Touros and Pureza have a direct participation in the basin. Basin in study have it lands evaluated according to the agriculturist aptitude by the conventionally methodology practiced in the country, having as objective, then, a compara-tive analysis between the ambient unities, Aeolian littoral and coast tray, identified in the researched area. From the characterization of the physic way of the area in study and owning the kept data, it was proceeded the integrated analysis of the structural elements of the landscape which were evidenced that the fragile areas are associated with the areas of agriculture cultivation, such as the ones of irregular occupation. About the degradation, the ambient diagnostic of the basin indicated that the equivalent to the Aeolian Littoral Ambient Unit correspond to the bigger pledging of the ambient quality, in other words, high ambient fragility, being this result due to the use and occupation of the soil, propitiating this way, vulnerability in the vegetal cover of the area, despite it disposes of a low agriculture cultivation percentage. Already in the Coast Ambient Tray, is emphasized the medium ambient fragility, despite of the high index of cultivated area. In a general way, the total area of the hydrographic basin of Punaú river and adjacent areas presented ambient impacts over the tolerance limit, indicating the necessity of a review of the practices of use and handling of the soil, reforesting of the water courses edges, control of erosion and contamination of the aqueous in the perspective to reduce the effects of the impacts due to the use and occupation of the basin in regard. The present search evaluated the ambient impacts diagnosised in the hydrographic basin of Punaú river and adjacent areas, pointing the causes and the probable consequences of the damages caused by these impacts to the basin ambient. From the analysis of these data, if was possible to become explicit how they are fundamental as key elements in the process of decision taking in the ambient questions