Milton Marques Fernandes

Aporte e Decomposição da Serapilheira na Caatinga no Sul do Piauí

Studies on nutrient cycling in the Caatinga biome can support a better understanding of the ecological processes in that ecosystem. This study aimed to improve information related to the amount of organic material for litter formation, its chemical composition and required time for decomposition in a study area located in the Caatinga biome, municipality of Santa Luz, Piaui state, Brazil. The litterfall production was monthly collected between December 2010 and November 2011 using 10 collectors. The collected material was partially used as samples for soil analysis (N, K, P, lignin and tannin). The decomposition was assessed using litter bags. Our results indicate that litter deposition increases as precipitation decreases, mainly the leaf fraction. The greatest soil nutrient content was Nitrogen. It seems that the high concentrations of lignin and tannin in the Caatinga litter were responsible for decreasing the decomposition rate of the leaf litter.

Aporte e Decomposição da Serapilheira na Caatinga no Sul do Piauí / Litter Contribution and Decomposition in the Caatinga in Southern Piauí State, Brazil

Studies on nutrient cycling in the Caatinga biome can support a better understanding of the ecological processes in that ecosystem. This study aimed to improve information related to the amount of organic material for litter formation, its chemical composition and required time for decomposition in a study area located in the Caatinga biome, municipality of Santa Luz, Piaui state, Brazil. The litterfall production was monthly collected between December 2010 and November 2011 using 10 collectors. The collected material was partially used as samples for soil analysis (N, K, P, lignin and tannin). The decomposition was assessed using litter bags. Our results indicate that litter deposition increases as precipitation decreases, mainly the leaf fraction. The greatest soil nutrient content was Nitrogen. It seems that the high concentrations of lignin and tannin in the Caatinga litter were responsible for decreasing the decomposition rate of the leaf litter.

Mudanças do Uso e de Cobertura da Terra na Região Semiárida de Sergipe

This study performed a temporal analysis of the land use and coverage in the semiarid region of Sergipe. We used Landsat-5 TM and Landsat-8 OLI satellite images acquired in 1992, 2003 and 2013. The maximum likelihood algorithm was used to detect six classes of land use and land coverage. We used a high spatial resolution Spot-5 scene as reference data to validate the assigned land use and coverage classification. Our results indicate that deforestation of native vegetation increased approximately 26% in the study area. The Caatinga vegetation was the most impacted, mostly converted to pastureland. In addition, it was observed that the deforestation increase in the study area negatively affected the preserved Caatinga secondary regrowth.

Mudanças do Uso e de Cobertura da Terra na Região Semiárida de Sergipe / Land Use and Land Cover Changes in the Sergipe Semiarid Region

This study performed a temporal analysis of the land use and coverage in the semiarid region of Sergipe. We used Landsat-5 TM and Landsat-8 OLI satellite images acquired in 1992, 2003 and 2013. The maximum likelihood algorithm was used to detect six classes of land use and land coverage. We used a high spatial resolution Spot-5 scene as reference data to validate the assigned land use and coverage classification. Our results indicate that deforestation of native vegetation increased approximately 26% in the study area. The Caatinga vegetation was the most impacted, mostly converted to pastureland. In addition, it was observed that the deforestation increase in the study area negatively affected the preserved Caatinga secondary regrowth.

Applying the Meta Soil Model: The Complexities of Soil and Water Security in a Permanent Protection Area in Brazil

Soil security denotes freedom from risks of losing a specific or a group of soil functions. This case study in the permanent protection area of Sana river (PPA-Sana), Brazil, addresses the relationship between soil security and water security. It explores the soil function “the provision of clean water and its storage, as well as filtering the contamination of water ways.” The study also presents a formal way to put soil security into practice applying the meta soil model. Meta soil modeling is built on integral theory that facilitates to understand the complexity of soil, water, and other securities. The soil and water securities in the PPA-Sana are interconnected and at risk. Specifically, one of the main problems is the discharge of soil sediments in the rivers as a consequence of soil erosion. Soil erosion and compaction constrain soil and water security, and these were monitored and mapped in order to provide support for policy interventions. However, our findings suggest that producing better soil maps and more monitoring are not enough to improve soil and water security. On the contrary, awareness building, creating trust among stakeholders, and better integration among quadrants of the integral model would lead to an enhancement of soil and water security. In essence, cognizance (the sixth dimension of soil and other securities) is profoundly important to allow integration of human and biophysical system dimensions.

ANÁLISE ESPACIAL DA FRAGMENTAÇÃO FLORESTAL DA BACIA DO RIO UBÁ - RJ

This study aimed at mapping and analyzing the use of the land and the forest landscape structure in Uba river basin – RJ state, through landscape metrics. The mapping of the land use and of the forest fragments were performed through a CBERS 2B/HRC image. To calculate the ecology indexes, the program FRAGSTATS 4.2® was used. The mapped fragments were divided by size classes: 1- very small, smaller than 5ha, 2- small fragment, between 5 and 10ha, 3- medium fragment, between 10 and 100 ha, and 4- big fragment, bigger than 100ha.The quantitative analysis through the landscape metrics were performed with the class metrics: area, shape, central area, aggregation, and diversity, obtaining the central area in different simulations of edge effects (20, 40, 60, 80, 100 and 140 m). 47 forest fragments were mapped through all Uba river basin, representing 23.65% of forest cover. The medium fragments presented the greatest number (25), followed by the small ones (9), very small ones (7), and only two big ones. Uba river basin has a predominance of an anthropogenic matrix represented by grasslands, a small percentage of forest cover with medium fragments between 10 and 100 ha, with a high degree of forest landscape fragmentation. The medium fragments are the most numerous class with a wider total area accounting for the only size class that maintains a distance shorter than 100 m between themselves. Even though the very small fragments and the small ones presented more regular shapes, they had a greater edge density. In relation to the central area metrics, the very small and small fragments totally lost their central area, being completely under the edge effect considering an edge distance of 140 m. An alternative in the context of Uba river basin is the use of very small and small fragments as ecological corridors for the link with the medium fragments.

FAUNA DO SOLO EM ÁREA DEGRADADA REVEGETADA COM ENTEROLOBIUM CONTORTISILIQUUM NO SUL DO PIAUÍ

POLLINATOR FORAGING STRATEGY IN Galactia peduncularis (BENTH.) TAUB. (LEGUMINOSAE: PAPILIONOIDEA) IN THE PARQUE ESTADUAL DA SERRA DE CALDAS NOVAS BRAZIL The way the animals look for food is an important characteristic of their behavior. The optimal foraging theory is based on the existence of a balance between costs and benefits of these behavioral decisions. The present study aimed to evaluate the behavior of the pollinator in response to increased availability of floral resources. The experiment was conducted in a recently burned Cerrado area (Campo rupestre) in the State Park of Serra de Caldas Novas , located in the municipalities of Caldas Novas and Rio Quente Brazil. The species chosen to test our hypothesis was Galactia peduncularis (Benth.) Taub. (Leguminosae: Papilionoidea). 17 pairs of specimens were selected with a number of flowers, and the individuals of each pair were spaced by about 2m. In these pairs, one of them was considered the focal, and the other, the isolated. To test possible differences in pollination between isolated plants and focus, we performed two randomization tests: a test binary (TB), where all pairs were analyzed and verified the number of times where the focus on the individual floral visits were higher than the number of visits in isolated. According to the data analyzed, floral visitors preferred to use plants that could provide a greater amount of floral resources so that the number of visitors varied positively with the increment of flowers. Plants with many flowers can provide a greater amount of food in one location so that visitors do not need to flower around for long distances in search of meeting their energy needs.