Navegando por Assunto "Soils"

Agora exibindo 1 - 3 de 3

Acesso aberto (Open Access)
Aplicação da RUSLE a uma pequena bacia hidrográfica da Amazônia
(Universidade Federal do Pará, 2013-09-26) SANTOS, Diego Benvindo Oliveira; BLANCO, Claudio José Cavalcante; http://lattes.cnpq.br/8319326553139808
The Amazon is experiencing severe changes due to anthropogenic activities, among which the transformation of forested land into areas for agricultural use stand out, intensifying erosion processes. Erosion, especially the drag of particles by runoff, causes a reduction of soil fertility impairing agricultural productivity and impacting the quality and quantity of surface water resources, a fact compounded by strong rainfall and naturally poor soils in the region. In this context, knowledge of erosion processes, such as through the use of mathematical models for predicting soil loss helps in determining management practices for sustainable use of natural resources. This study aimed to evaluate the applicability of the empirical model RUSLE (Revised Universal Soil Loss Equation) in the region, which considers the interaction between the rain energy, soil and topography characteristics, as well as the uses and management practiced. This research applied the RUSLE in the upper basin of the Igarapé da Prata stream, with an approximate area of 37 km², located in the municipality of Capitão Poço, Pará, Brazil, approximately 160 km from the capital Belém, in Pará Northeast region. This research also consisted in the construction of a geo-referenced database made from public sources; such data passed through adaptations for insertion into the environment of the ArcGIS to quantify the parameters of RUSLE, which when combined allowed the generation of a map of soil loss for the study area. The small upper basin of Igarapé da Prata presented soil loss values ranging between 0.004 and 72.48 t/ha year, with an average value of 5.12 and a standard deviation of 6.97, where approximately 12% of its total area presents environmental risks due to erosive processes.
Acesso aberto (Open Access)
Modelos empíricos para estimativa de produção de sedimentos
(Universidade Federal do Pará, 2015-03-20) SILVA, Danielle Sebastiana dos Santos; BLANCO, Claudio José Cavalcante; http://lattes.cnpq.br/8319326553139808
The erosive processes that occur in a watershed have been objects of concerns associated with the planning and management of land use and water resources. In this case, the empirical models of hydrosedimentological simulation are important tools, and with low cost, in the assessment of soil erosion due to the use and management of land. Thus, the study aimed to analyze the sediments yield via three empirical models applied to a small catchment of the Amazon, the catchment of Igarapé da Prata located in the municipality of Capitão Poço-PA. The analyzed and used models were the USLE (Universal Soil Loss Equation); the Poesen model; and the Langbein-Schumm model. The results showed that the USLE model had an average sediment yield equal to 146.20 (t / km²); the Langbein-Schumm model an average production equal to 114.25 (t / km²); and the Poesen model an average yield equal to 7.57 (t / km²). The results obtained by the two first-mentioned models are of the same order of magnitude, indicating that the Langbein-Schumm model, for the case analyzed, is comparable to the classical model USLE. These results were compared with observed data of suspended sediments and the Langbein-Schumm model was the one closest to the observations.
Acesso aberto (Open Access)
Ocupação de terrenos de marinha: risco e regulamentação jurídica.
(Universidade Federal do Pará, 2019-06-10) SANTOS, Jéssica de Souza Teixeira; BORGES, Maurício da Silva; http://lattes.cnpq.br/1580207189205228
The present research has as objective to treat the marine lands and their increased, that as assets of the union, were also instituted as source of income of the same. Currently, they are enshrined in the federal constitution of 1988, as well as by decree-law no. 9,760 / 1946, by decree no. 3,725 / 2001, as well as by law no. 9,636 / 1988. The navy lands and their awnings may be established as sunday goods, goods of common use of the people and goods of special use. It is extremely important to also consider pec no. 39/2011, which aims at securing the land of the navy, as well as the question of the demarcation of these lands that is presented from the preamar average line of 1831, and the secretariat of the patrimony of the union - spu civil liability and the principles of environmental law, as well as the multidisciplinarity of disciplines of civil law, environmental law and disaster law, are necessary in order to the compression of the dimension of the subject and the problem presented. It is also understood that it is necessary to maintain the institute of marine lands as a good of the union, looking not only for the collection interest, but mainly for preservation, as well as for environmental recovery, transforming this institute into real service of the socio-environmental function and, moreover, as being mainly recognized with a constitutional aspect. Based on the results obtained, and based on the analysis carried out on the study of the demarcation of brazilian navy lands, based on the national characterization plan developed by the spu, it was verified that much remains to be done in relation to the demarcations and, the importance of the navy land remaining as assets of the union, overcoming the lack of instruments and advancing to the recognition of the constitutional expression of this institute and in this way, the research went to the creation of a "normative act" in the species "recommendation", to the technicians of the municipal government of abaetetuba, who are involved with the public service situations inherent to the marine lands.