José Marinaldo Gleriani

O desafio da delimitação de áreas de preservação permanente

The demarcation of permanent preservation areas is a complex process, jeopardizing both the surveillance tasks and law enforcement. This paper presents a GIS-based alternative to the traditional labor-intensive approach - manual features extraction using paper maps and photogrammetry techniques. The methodology relies on the new recent concept of hydrologically correct digital elevation models and has as principal advantages the consistency and reproducibility of the results, besides savings on both time and labor. Considering the recent availability by NASA of SRTM (Shuttle Radar Topography Mission) data on a continental scale, the results clearly show that, from now on, the enforcement of the Forest Code in Brazil is just a matter of political willingness.

Adjustment of the Schumacher and Hall model and application of artificial neural networks to estimate volume of eucalypt trees

This research aimed at evaluating the adjustment of Schumacher and Hall volumetric model by different algorithms and the application of artificial neural networks to estimate the volume of wood of eucalyptus according to the diameter at breast height (DBH), total height (Ht) of the clone. For such, 21 scalings of stands of eucalyptus clones were used with DBH ranging from 4,5 to 28,3 cm and total height ranging from 6,6 to 33,8 m. The Schumacher and Hall volumetric model was adjusted linearly and nonlinearly with the following algorithms: Gauss-Newton, Quasi-Newton, Levenberg-Marquardt, Simplex, Hooke-Jeeves Pattern, Rosenbrock Pattern; Simplex, Hooke-Jeeves, and Rosenbrock, used simultaneously with the Quasi-Newton method and the principle of Maximum Likelihood. Different architectures and models (Multilayer Perceptron - MLP and Radial Basis Function - RBF) of artificial neural networks were tested and the networks that best represented the data were selected. Estimates of the volumes were evaluated by graphics of estimated volume according to the observed volume and by the LO the Gauss-Newton, Quasi-Newton and Levenberg-Marquardt algorithms were effective in the adjustment of Schumacher and Hall volumetric model. The artificial neural networks showed good adequacy to the problem and are highly recommended to perform production prognoses of planted forests.

Identificação de conflito de uso da terra em áreas de preservação permanente no entorno do parque nacional do Caparaó, Estado de Minas Gerais

The objective of this work was to prepare a map of land use based on the IKONOS II sattelite images, to automatically determine the permanent preservation areas and to identify the occurrence of use conflicts, using as legal reference the Forest Code and the no 303 Resolution of the CONAMA. The research was developed around the Caparao National Park, in lands of the municipalities of Alto Jequitiba, Alto Caparao, Caparao and Espera Feliz, all of them located in the State of Minas Gerais. Using the resources available in the geographic processing, it was possible to map 8 classes of land use and to delimitate the permanent preservation areas located in regions above 1,800 meters of altitude (8.42 ha), the third upper part the hills (18.67 ha); an hillsides with slopes above 45 degrees (92.96 ha); water course margins with width below 10 meters (3,957.19 ha); and the upper third part the sub basins totalizing 12,098.22 ha (48.06%) of the basin total area. The area of improper use corresponds to 8,922.91 ha (45.49 %), being the classes coffee crop (5,183.43 ha) and clear pasture (3,650.74 ha) the main occurrences in these areas. Only 2,160.69 ha (18.40 %) of the permanent preservation areas are protected by natural vegetation.

Análise da dinâmica de fragmentos florestais no município de Carandaí, MG, para fins de restauração florestal

The knowledge on forest patches in rural properties allows the application of a correct environmental administration, promoting their conservation and restoration in degraded areas. By using the softwares SPRING and FRAGSTATS, the landscape was characterized with emphasis on the patches of secondary Seasonal Semidecidual Forest, located in the municipal district of Carandai, MG, and the area around it, considering its evolution from the period of 1984 to 2007. It could be concluded that progressive increase in the total area of native forest occurred due to the appearance of new patches, and the individual area of each patch presented reduction tendency, what provided increase of the edge area, reducing the percentage of each patch which is the core area during the gap of the evaluated time. Despite the advantage of predominance of patches in simple geometric ways, with reduction of the edge effect, the quality of the landscape got threatened because it was predominantly constituted by small patches. The forest patches were still so distant one from the others (more than 200 meters), presenting small gathering tendency (result of the increase of the number of patches), however, still insufficient. Therefore, although the covering of native forest has presented increase of total area, in general, it lost in quality in the gap of the time considered.

Análise espacial de fragmentos florestais na Bacia do Rio Itapemirim, ES

The objectives of this study were to map and analyze the structure of forest landscape in a representative area of Itapemirim river basin, ES, through indexes of landscape ecology. The mapping of forest fragments was obtained using image interpretation techniques on a scale of 1:1500 of the ortho-image-mosaic of the year 2007. For the ecology metrics calculation, the extension Patch Analyst was used within the computational application ArcGIS 9.3. In general, 3285 forest fragments were found in all the area, representing 17% of the forest covering. The mapped fragments were divided into size classes, considering as small those fragments smaller than 5 ha, average fragments have size between 5 and 50 ha, and large fragments are larger than 50 ha. The small fragments were found in greater number (2,236), followed by average fragments (749), and finally the large fragments, comprising only 100 spots. The number of fragments of each size class has an inverse relationship with the contribution in area of the same class within the forest fragmentation. Quantitative characterizations through landscape metrics were made with groups of area index, density and size, shape, proximity and central area, which was obtained from different simulations of edge effect (20, 40, 60, 80, 100, 140 and 200 m). For all the indexes there were differences on size classes of forest fragments. Most of the basin forest fragments are small, less than 5 h, and the distance of edge 100 meters completely eliminates the central area of these fragments. Although large fragments present the most irregular shapes, they have a higher index central area even under the effect of the greater distance of the edge effect.

Spatial and temporal distribution of urban heat islands

The formation of an urban heat island (UHI) is one of the most common impacts of the urbanization process. To mitigate the effects of UHI, the planning of urban forests (e.g., creation of parks, forests and afforestation streets) has been the major tool applied in this context. Thus, the aim of this study is to evaluate the spatial and temporal distribution of heat islands in Vila Velha, ES, Brazil using the mono-window algorithm. The study followed these methodological steps: 1) mapping of urban green areas through a photointerpretation screen; 2) application of the mono-window algorithm to obtain the spatial and temporal patterns of land surface temperature (LST); 3) correlation between LST and the normalized difference vegetation index (NDVI) and normalized difference build-up index (NDBI); 4) application of ecological evaluation index. The results showed that the mean values of LST in urban areas were at least 2.34 to 7.19°C higher than undeveloped areas. Moreover, the positive correlation between LST and NDBI showed an amplifying effect of the developed areas for UHI, while areas with a predominance of vegetation attenuated the effect of UHI. Urban centers, clustered in some parts of the city, received the worst ecological assessment index. Finally, the adoption of measures to guide the urban forest planning within urban centers is necessary to mitigate the effect of heat islands and provide thermal comfort in urban areas.

BANCO DE SEMENTES DO SOLO E SERAPILHEIRA ACUMULADA EM FLORESTA RESTAURADA

Este estudo teve por objetivo avaliar o banco de sementes do solo e a serapilheira acumulada em uma floresta restaurada por meio de plantio, com 40 anos, em Vicosa, MG. Foram alocadas 16 parcelas contiguas de 25 x 25 m, cobrindo toda a area da floresta (1 ha). Em cada parcela, foram coletadas cinco amostras de solo superficial (0,30 x 0,30 x 0,05 m) para avaliacao do banco de sementes pelo metodo de germinacao e uma amostra de 1,0 m2 de serapilheira para avaliacao da serapilheira acumulada. Foi realizada a classificacao dos individuos e especies de plântulas registrados do banco de sementes quanto a categoria sucessional, sindrome de dispersao e habito de vida. Foram registradas 5.555 plântulas pertencentes a 32 familias e 93 especies e um morfotipo que reuniu todas as trepadeiras. Registrou-se o predominio de sindrome de dispersao zoocorica e, quanto ao habito de vida, maior percentual de ervas, em nivel de especie (48,6%) e de individuo (44,8%). Entre as especies arbustiva-arboreas, observou-se maior percentual da categoria sucessional pioneira, em nivel de especie (75,1%) e de individuo (85,1%). A serapilheira media acumulada foi de 3.432 kg ha-1, com a fracao foliar representando 65% e correlacao significativa com a area basal (p = 0,031; R2 = 0,29) do estrato arboreo. Os resultados indicam que o banco de sementes do solo da floresta restaurada, apos 40 anos de sua implantacao se assemelha, quanto as relacoes ecologicas, as areas de floresta estacional semidecidual na mesma regiao e a outras areas restauradas que tambem foram utilizados plantio de mudas.

Produção de mudas de espécies arbóreas nativas em viveiro via resgate de plantas jovens

RESUMO – A dificuldade na obtencao de mudas com alta diversidade nos viveiros florestais tem levado a perda de diversidades biologica e genetica nos projetos de restauracao de areas degradadas. Este estudo apresenta alternativa para minimizar esse problema, utilizando a tecnica do resgate de plantas jovens, as quais foram obtidas de dois fragmentos florestais em diferentes estadios de sucessao ecologica (media e inicial), localizados no Municipio de Carandai, MG. Individuos com ate 60 cm de altura foram transplantados para viveiro e avaliados durante seis meses. Foi resgatado um total de 966 individuos, pertencentes a 26 familias, num montante de 70 especies, com maior porcentagem dessas observada no fragmento com estadio sucessional mais avancado. A taxa media de sobrevivencia foi de 79,3%, diferindo estatisticamente entre os fragmentos, altura dos individuos e especies. Individuos provenientes do fragmento de estadio inicial, assim como os de altura inferior a 40 cm, caracterizaram-se pela maior taxa de sobrevivencia. Verificou-se alta sobrevivencia de plantas, tanto de especies pioneiras quanto de nao pioneiras, muitas comumente nao encontradas nos viveiros florestais e, por consequencia, tambem ausentes nos projetos de restauracao. Portanto, a tecnica de resgate de plantas jovens e estrategia complementar viavel, de baixo custo, que pode contribuir para o aumento da diversidade nos viveiros florestais e nos projetos de restauracao florestal.

Atmospheric effects on vegetation indices of TM and ETM+ images from a tropical region using the 6S model

Vegetation indices have been widely used for monitoring vegetation and to estimate vegetation biophysical parameters. The atmosphere affects differently sensor bands depending on the waveband, thus affecting the indices obtained from top of the atmosphere reflectances. The objective of this paper is to evaluate the atmospheric effects on the NDVI and SAVI using the 6S model adapted for atmospheric correction of images of eight bits digital numbers. Images from the TM and ETM+ sensors of the same area were corrected for the atmosphere and the vegetation indices were compared with those from noncorrected images. For these images the results show that the vegetation indices at the top of the atmosphere were lower than those from the surface. This underestimation of the vegetation indices due to the atmosphere is attributed to a higher absorption of radiation in the near infrared than in the red spectral region. This is exceptionally pronounced on tropical atmospheres where absorption by water vapor tends to be higher than in mid-latitudes. It is concluded that atmospheric correction is necessary when calculating vegetation indices over tropical regions and the adapted 6S model is suitable for this task.

PROGNOSE EM NÍVEL DE POVOAMENTO DE CLONES DE EUCALIPTO EMPREGANDO REDES NEURAIS ARTIFICIAIS

Objetivou-se, neste estudo, treinar, aplicar e avaliar a eficiencia de redes neurais artificiais (RNA) para realizar a prognose da producao de povoamentos equiâneos de clones de eucalipto. Os dados utilizados foram provenientes de povoamentos localizados no sul da Bahia, totalizando cerca de 2.000 hectares de floresta. Foram utilizadas variaveis numericas, como: idade, area basal, volume e variaveis categoricas, como classe de solo, textura, tipos de espacamento, relevo, projeto e clone. Os dados foram divididos aleatoriamente em dois grupos: treinamento (80%) e generalizacao (20%). Foram treinadas redes de tres tipos: perceptron, perceptron de multiplas camadas e redes de funcao de base radial. As RNA que apresentaram os melhores desempenhos no treinamento e generalizacao foram selecionadas para realizar a prognose com dados, a partir do primeiro inventario florestal. Conclui-se que as RNA apresentaram resultados satisfatorios, comprovando o potencial e aplicabilidade da tecnica na solucao dos problemas de mensuracao e manejo florestal.