Teses em Ciências Ambientais (Doutorado) - PPGCA/IG

URI Permanente para esta coleçãohttps://repositorio.ufpa.br/handle/2011/9341

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Efeitos de intervenções técnico-produtivas para a sustentabilidade do uso da terra em agroecossistemas familiares no território do Baixo Tocantins, PA
(Universidade Federal do Pará, 2017-09-28) SIMÕES, Lourdes Henchen Ritter; RUIVO, Maria de Lourdes Pinheiro; http://lattes.cnpq.br/9419564604488031
The study deals with the sustainability of land use in family agroecosystems located in the municipalities of Cametá (communities Ajó and Inacha) and Moju (PA Calmaria II, communities of São José and Água Preta), belonging to the territory of Low Tocantins, state of PA, proposing to compare the main effects resulting from two modes of interventions in the technical-productive systems. The two interventions were established proposing innovations and improvements for sustainable development, the first in Cametá, promoted by "networks of multiplier farmers" with proposals for agroecological use and management and the second in Moju refers to programs to encourage palm oil plantation.The main focus of the study is based on the following questions: what are the main effects on sustainability that the innovations in land management and sustainable development introduced by the National Program for the Production and Use of Biodiesel (PNPB) on the one hand and Networks of multiplier farmers, with agroecological management proposals on the other, lead to family agroecosystems? Have these interventions provided improvements with sustainability? The research hypothesis suggests that the technical-productive innovations promoted in family agroecosystems by the multiplier farmers are more sustainable. The general objective is to analyze the main effects of technical-productive interventions in land use, on the sustainability of family agro-ecosystems. The specific objectives are to verify if the interventions provided improvements with socio-environmental quality; to evaluate comparatively the quality of the soil in systems of use of familiar agro-ecosystems, that had differentiated technical-productive interventions; and to distinguish the main modes of use practiced in the familiar agroecosystems in order to elucidate their relations with the biophysical environment and with the different ways of managing the fertility of the environment. For the development of other companies in other regions in Cametá: Caripi, with dry land ecosystem and Cupijó, with dry land ecosystems and floodplains. The methodological procedures used were surveys with semi-structured forms and description and soil collect for laboratory analysis. The results obtained from four dimensions indicators of sustainability showed that the interventions, to a certain extent, reached the objectives, but many problems were observed, such as those that reflect a relationship between farmers and technicians, that still can not surpass the conception of "transmission of knowledge and technology", in the case of the intervention in Calmaria II. In the communities of Ajó and Inacha, the most determining reasons for some differences would be the assiduity and intensity of technical assistance attributed more to Ajó; The fact that these family agroecosystems have availability of a diversified biophysical environment (dry land and foodplain), allowing greater variation in production systems; and the consequent reduction of the use of fire. In the communities of São José and Água Preta the most significant cause of the distinctions between them would be that São José has a higher income, due to the period of the palm harvest, which coincides with that of the Água Preta (neighboring community to the large palm oil plantations. This fact guarantees a better price of the production to São José. This difference in the harvest and off-season months would be related to the water supply, available to the culture in São José, during the rainy season, caused the main differences between the two types of agro-ecosystems are that they do not have the same characteristics as the biophysical environment, and that there are different levels of satisfaction with the oil palm. Environment are determined by the management of the fertility of the environment of each one, constituting the differentiation between the production systems in each specific environment. The data indicated that, according to the environments, farmers take advantage of the different potentialities of use, adapting the ways of managing the fertility of the natural environment. The soil attributes that were considered significant to evaluate sustainability indicate that the land uses studied presented little expressive differences. The biophysical environment was determinant for some types to stand out positively. By the pedological analysis of Ajó locality (SAF) it is noticeable that their soils are more naturally enriched in exchangeable bases (K+, Ca2+, Mg2+). In São José, some physical factors are better, because the soils retain water for a longer time, making this available to the palm oil tree for a longer period in the dry season.
Acesso aberto (Open Access)
Mudanças de uso da terra em paisagens agrícolas com palma de óleo (Elaeis guineensis Jacq.) e implicações para a biodiversidade arbórea na Amazônia Oriental
(Universidade Federal do Pará, 2015-09-30) ALMEIDA, Arlete Silva de; VIEIRA, Ima Célia Guimarães; http://lattes.cnpq.br/3761418169454490
The expansion of oil palm in the Amazon is associated with a number of public policy, in the form of actions and programs and has provoked economic and ecological changes in the region and challenge the society to monitor and control the palm cultivation expansion on a large scale. The municipalities from the "Palm region" in Pará state, as Moju, intensified cultivation of this palm tree and suffered intense modifications in thier natural ecosystems. In Addition this new frontier of bioenergy challenged the paradigm of sustainability, with social and environmental conflicts and replacement of subsistence farming by the palm. Little is known about the consequences that a large-scale monoculture can cause in the amazonian environment. To follow this new productive dynamic with palm oil are required interdisciplinary studies that contribute to identify how environmental respond to changes associated to the new agricultural frontier with oil palm. In this context, the overall objective of this research is to analyze the changes, the conflicts and the trajectories of land uses, as well as the value of conservation of the biodiversity of the plantations of oil palm and other land uses predominate in eastern Pará. The work is organized into five chapters including the first one which introduce the subject of the thesis. The other four are guided by the following specificobjectives: a) analyze the land use conflicts in Moju county, Pará state, Brazil, within areas of permanent preservation -PPA, according with the Brazilian Forest Code of 2012; b) map and quantify the types of land cover and land use in 2013 in three areas (Ubá, Arauaí e Mamorana), where the implementation of oil palm cultivation is present; c) capture the space-time variability in the changes of trajectories in landscapes of 1991-2013 and identify the effect of changes of land use in the structure of the landscape; and d) investigate the variation in the carbon stock and species richness of trees in different land use and vegetation cover in the three studied areas. For the study of conflicts in APPs in Moju, were used 29 multispectral images of high resolutions by RapidEye satellite of 2010. The results show that the area destined legally for permanent preservation (APP) in Moju is 47,357.06 ha, representing 5.21% of the municipal area. The PPAs with natural vegetation represent 68.60% of the APPs of the municipal area, about 28% of the PPAs have use conflicting with predominance of pasture in 15.6%. Only 0.63% of APPs is occpupied by palm oil. The application of the new recomposition guidelines for APPs according to the new Forest Code will result in the loss of 60.69% of the APP-recovered areas in this municipality. The analysis of vegetation cover and land use in 2013 in the three selected areas (Ubá, Arauaí and Mamorana) was made by the method of decision tree in images of the satellite Landsat-8 year of 2013. The overall performance of the classification was 0.87% (index kappa). The results show greater extension of primary forests in Mamorana, area in the beginning of cultivating oil palm. Agriculture predominate in all areas analysed. For the analyses of trajectories changes of land uses and the effects on the landscape structure i the landscape we made classification using decision tree method in images of the satellite Landsat TM-5 for the years 1991, 1995, 2001, 2005 and 2010, and Landsat-8 for the year 2013, through the ImgToos programs, ENVI and ArcGIS. The landscape structure was carried out through the landscape metrics (PLAND, LPI, PD and PROX-MN) using the FRAGSTATS program. v. 3.3. The classification achieved overall performance of 0.87% for the kappa index. In the period 1991-2013 the conversion of primary forest to other uses occurred in a ratio of 47.82%, while the degraded forest (17%) and oil palm (11%) had the largest increase in occupancy in 2013. We emphasize that the transition of the primary forest to palm oil was 20% in the 22 years under study, which led to a PD (fragments density index) with considerable amounts, attaining a level from 0.3 to 4.5 (number of patches/ 100 ha). Such conversions define the fragmentation intensity of primary forest. The investigation about the biodiversity response and carbon stocks in different forest cover and land uses was made through a floristic inventory of trees greater than or equal to 2 cm DBH in plots ranging from 1, 500 and 2500 m2 on each forest cover/land use analyzed. Intheall 8.55 ha sampling were registered 5,770 individual trees, distributed in 425 species and 74 families. The primary forest presented carbon stock higher than 80 Mg/ha, while palm oil, pasture and secondary forest presented less than 50 Mg/ha, noting that the oil palm retains impoverished communities of trees, and its tree composition is poorer than the pasture, while the stock of carbon is higher. In this study, in 22 years of the analysis we observed that primary forests covers less than 30% of the landscape, a critical level for biodiversity conservation.

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