Areas Of Secondary Vegetation Research Articles

Forest regeneration pathways in contrasting deforestation patterns of Amazonia

Secondary vegetation is increasingly recognized as a key element for biodiversity conservation and carbon stocks in human-modified landscapes. Contrasting deforestation patterns should lead to distinct patterns of forest regeneration, but this relationship is yet to be unveiled for long-term studies. Using Landsat data from 1985–2015, we analyzed the surface area, spatial distribution, and age of secondary vegetation in Fishbone and Geometric patterns of deforestation. Additionally, we investigated to which extent secondary vegetation reduces forest patch isolation at the landscape level across time. We found the Fishbone pattern to consistently have more secondary vegetation over time than the Geometric pattern, despite having the same size of the deforested area. However, the Fishbone pattern showed more secondary vegetation area with less than 5 years old, while the Geometric pattern showed more area with secondary vegetation with more than 30 years old. Regarding spatial distribution, we found secondary vegetation to be more spread across the entire landscape at the Fishbone pattern and to consistently reduce forest patch isolation across time. This is congruent with the land use typically found in Geometric (industrial cropping and ranching) and Fishbone (fallow agriculture with small-scale ranching) patterns. These findings indicate that the Fishbone pattern of deforestation produces a more biodiversity-friendly landscape structure than the Geometric pattern. On the other hand, older secondary vegetation found in the Geometric deforestation pattern could indicate more carbon stocked in those landscapes. Future public policies of land use and occupation should consider better landscape planning and management to overcome this duality and create synergies between biodiversity conservation and secondary vegetation carbon stock.

Sustainability indicators in the agroforestry systems of family farmers in the district of Tomé-Açu, Pará

The aim of this article was to evaluate, using sustainability indicators, agroforestry systems (AFS) on the properties of family farmers in the district of Tomé-Açu, Pará, arising from the transition processes of different production systems. Eight AFS, three areas of secondary vegetation, and three conventional systems were evaluated. Direct observation was used to evaluate the sustainability indicators, assigning a value from 1 to 10 to each indicator (1 - undesirable; 5 - moderate and 10 - ideal). The mean value of the indicators was determined for each system under evaluation. The areas under conventional systems had the lowest value, of 0.25 for the crop-health indicators and 1.32 for soil quality, which suggests the need for proper management to prevent environmental problems in areas of pasture, cleared land and monocropped black pepper. The highest values of 4.1 for the crop-health indicators and 6.99 for soil quality, were obtained in the areas of secondary vegetation, and values of 3.0 for crop health and 6.1 for soil quality in the areas of AFS-BP, emphasising the role of secondary vegetation and agroforestry systems in recovering the productive potential of agrosystems. It can be concluded that the use of a simple technique (radar charts) together with statistical methods show that secondary vegetation, agroforestry and conventional systems differ; however, secondary vegetation and AFS are more sustainable, as they showed better results for each of the indicators under evaluation compared to the conventional systems.

Meliaceae (Sapindales): riqueza y distribución en el estado de Tabasco, México

Antecedentes y Objetivos: Con la finalidad de actualizar el listado de especies de Meliaceae en el estado de Tabasco bajo el sistema de clasificación actual, se completó una revisión taxonómica de la familia, como contribución al proyecto “Flora de Tabasco”. Métodos: Se llevó a cabo una revisión en herbarios estatales y nacionales de los ejemplares de las especies de la familia Meliaceae y se realizaron colectas en campo de 2015 a 2017 en vegetación secundaria y primaria del estado. El material colectado fue identificado por medio de claves taxonómicas y cotejado con material de herbario. También se consultaron los ejemplares tipo disponibles en JSTOR Global Plants. Se hizo una clave de identificación para las especies de la familia en Tabasco y un análisis de distribución por tipo de vegetación y datos ecológicos; así mismo se registran nombres comunes y se ilustran algunas de las especies. Resultados clave: La familia Meliaceae está representada por 11 especies en cuatro géneros nativos y dos especies en dos géneros introducidos. Se registran por primera vez dos especies para el estado. El género Trichilia es representado por siete especies, seguido de Guarea con dos. Los municipios con el mayor número de especies son Centro y Teapa con ocho especies cada uno y Balancán con siete. Conclusiones: Las Meliáceas nativas presentes en la zona de estudio representan 45.83% de las 24 especies nativas estimadas para la familia en México y están distribuidas principalmente en áreas de vegetación secundaria y manchones de selva en municipios serranos fronterizos con Chiapas y Guatemala.

Impacts of Public and Private Sector Policies on Soybean and Pasture Expansion in Mato Grosso—Brazil from 2001 to 2017

Demand for agricultural exports in Brazil has stimulated the expansion of crop production and cattle raising, which has caused environmental impacts. In response, Brazil developed public policies such as the new Forest Code (FC) and supply chain arrangements such the Soy and the Cattle Moratoriums. This paper analyzes the effectiveness of these policies, considering the trajectories of agricultural expansion in the state of Mato Grosso in three years: 2005 (pre-moratorium and before the new FC), 2010 (post-moratorium and before the new FC) and 2017 (post-moratorium and post-new FC). Our analysis uses a detailed land use change data for both the Amazon and Cerrado biomes in Mato Grosso. In all the years considered, soybean expansion occurred in consolidated production areas and by conversion of pastures. Pasture expansion is influenced by existence of pastures nearby, by areas of secondary vegetation and deforestation. Our data and models show the effectiveness of public policies and private arrangements to reduce direct conversion from forests to crop production. However, our results also provide evidence that soybean expansion has caused indirect impacts by replacing pasture areas and causing pasture expansion elsewhere. Evidence from our work indicates that Brazil needs broader-ranging land use policies than what was done in the 2010s to be able to reach the land use goals stated in its Nationally Determined Contribution (NDC) to the Paris Agreement.

Estimation of sediment production in oil palm expansion areas in the Amazon

ABSTRACT Currently, an activity that has become strategic at a national level is the cultivation of oil palm (Elaeis guineensis) in the northeast region of the Pará State, in eastern Brazilian Amazon. However, the impacts of this crop expansion on the hydro-sedimentological cycle are still unknown. Therefore, this study estimated the impacts of oil palm crop expansion on sediment production in a sub-basin under consolidated use of this crop. The Soil and Water Assessment Tool (SWAT) model was applied in the Mariquita sub-basin, calibrated by the flow regionalization technique, using data measured in the field with a current meter. Simulation results indicated an increase in sediment production between the years 2008 and 2013, which can be attributed to the large reduction of areas of secondary vegetation that were replaced by pasture, oil palm and general agriculture. Oil palm areas had a lower average monthly sediment yield in the rainiest period in all simulated years, compared with areas of general agriculture and pasture.

Technological innovations in the propagation of Açaí palm and Bacuri

ABSTRACT Açaí palm (Euterpe oleracea Mart.) and bacuri tree (Platonia insignis Mart.) are two important fruit species native to the Brazilian Amazon. The first species is widely cultivated in the Brazilian Amazon and with some orchards established in other regions of Brazil. Nevertheless, most of its production still comes from the dense and diversified native açaí orchards found in the floodplains of the Amazon River estuary and that in the last two decades have been managed for the production of fruits. The production of the second species is still dependent on extractivism of abundant natural populations in areas of secondary vegetation. Both species reproduce naturally sexually and asexually. In the case of açai tree, asexual reproduction occurs by means of the emission of tillers in the base of stems. For bacuri tree, reproduction is verified by means of abundant sprouts that arise from roots that develop horizontally, near the ground surface. The propagation of açaí palm tree, particularly sexually is a consolidated process, practically without innovations in the last years. Açaí seeds show rapid and relatively uniform germination. A seedling obtained from seeds is suitable for final planting four to six months after emergence of seedlings. Regarding propagation by asexual route, it has been demonstrated that tillers can be used for the production of seedlings. For this, they should be separated from the mother plant when they have two completely expanded leaves and one at the beginning of formation. The big challenge is to increase the multiplication rate of tillers. For bacuri tree, considerable advances have been obtained both for sexual and asexual propagation. Propagation by primary root cuttings or direct seeding at the definitive site constitutes innovations that overcome the problem of the slow and uneven germination of the bacuri seed. The developed grafting techniques allow both the production of grafted seedlings and grafting in the field, for plants from direct seeding.

Diagnóstico de qualidade ambiental do Parque Estadual Vitório Piassa por meio do uso de besouros bioindicadores

O presente trabalho teve como objetivo analisar a qualidade ambiental em um fragmento florestal de Mata Atlântica próximo a uma área urbana. O estudo foi realizado no Parque Estadual Vitório Piassa, situado no município de Pato Branco, Paraná, onde coletas de besouros da subfamília Scarabaeinae foram realizadas através de armadilhas de queda em três áreas distintas dentro do parque, entre fevereiro e março de 2015. Foram coletados no total 945 indivíduos pertencentes a 22 espécies, dos quais 366 indivíduos de 18 espécies foram coletados na área de vegetação mais densa, 291 de 18 espécies na área de vegetação secundária e 288 de 16 espécies na área mais antropizada. As espécies mais abundantes foram Dichotomius mormon e Eurysternus parallelus, somando juntas mais de 50% do total de indivíduos capturados. Os índices de diversidade (Shannon e Simpson) e de equitabilidade (Pielou) foram maiores na área com vegetação secundária, o que pode ser explicado por ser uma área intermediária, tanto em termos espaciais como temporais. A análise de similaridade baseada no índice de Bray-Curtis mostrou a formação de dois grupos: um constituído pelas assembleias das áreas em regeneração e o outro apenas pela área de vegetação mais densa, principalmente devido à grande abundância de besouros nesta área. Assim, foi possível observar que o Parque mantém uma qualidade de habitat que permite abrigar uma grande abundância de muitas espécies de escarabeíneos, principalmente nas áreas mais conservadas.

Dynamic of dominance, growth and bromatology ofEragrostis planaNees in secondary vegetation area

The objective of this work was to evaluate the dominance, growth and bromatology of tough lovegrass or 'annoni' grass (Eragrostis plana) in secondary vegetation area. The evaluations were carried out at 23, 45, 64, 86, 111, 132, 153, and 174 days of growth after a mowing. The tough lovegrass was the dominant species on the area, accounting for 76 to 90% of biomass. There was a linear increase for leaf (9.8 kg DM ha -1 day -1 ) and total dry mass (16.9 kg DM ha -1 day -1 ) of the tough lovegrass. During the 111 days of the vegetative stage, the biomass was composed only of leaves, and the flowering started at 132 days. At 174 days, the tough lovegrass accumulated about 4,000 kg DM ha -1 , 650 kg DM ha -1 of wh ich was composed of inflorescences. The growth analysis revealed a specific leaf area of 72 cm 2 g -1 and a maximum leaf area index of 2.1. The leaf area ratio decreased from 72.2 to 43.9 cm² g -1 between the 23 rd and 174 th days. The bromatological analysis showed a high content of neutral detergent fiber (85.3-90.4%) and acid detergent fiber (39.4-42.8%), as well as low crude protein content (3.9-9.9%), indicating the low forage quality of the species.

Cambios en la dinámica de deforestación de la subcuenca de un río en México: la imposibilidad de recuperación de los hábitats originales después del cese de la deforestación

In the Neotropical area of the Rio Apatlaco sub-basin (central Mexico), high deforestation can be attributed to urban development, as this area concentrates the highest human population density in Morelos state. The objective of this study was to analyze changes in land use and vegetation in this sub-basin from 2002 to 2012 using geographic information systems. The results show that, over the period of analysis, the main changes occurred in the grassland and coniferous forest. However, in the tropical dry forest (TDF) the annual rate of deforestation (0.13%) was much lower than previously estimated (1.4%), but no recovery took place. It is possible that deforestation of the TDF was halted because the remaining areas with forest remnants were unsuitable for agricultural activities and/or abandonment of such activities has taken place. It is therefore a priority to protect these areas of secondary vegetation that serve as a buffer for conserved areas, allowing their recovery and contributing to their interconnectivity.

Changes in the deforestation dynamics of a river sub-basin of Mexico: non-recovery of primary habitats following cessation of deforestation

In the Neotropical area of the Rio Apatlaco sub-basin (central Mexico), high deforestation can be attributed to urban development, as this area concentrates the highest human population density in Morelos state. The objective of this study was to analyze changes in land use and vegetation in this sub-basin from 2002 to 2012 using geographic information systems. The results show that, over the period of analysis, the main changes occurred in the grassland and coniferous forest. However, in the tropical dry forest (TDF) the annual rate of deforestation (0.13%) was much lower than previously estimated (1.4%), but no recovery took place. It is possible that deforestation of the TDF was halted because the remaining areas with forest remnants were unsuitable for agricultural activities and/or abandonment of such activities has taken place. It is therefore a priority to protect these areas of secondary vegetation that serve as a buffer for conserved areas, allowing their recovery and contributing to their interconnectivity.

Passiflora echinasteris: a new species of subgenus Passiflora, series Serratifoliae (Passifloraceae) from the Brazilian Amazon

Passiflora echinasteris from a secondary vegetation area on the Great Curve of the Xingu River, in the Brazilian Amazon, is newly described. It belongs to the series Serratifoliae with three other Brazilian species. The new species is illustrated and its affinities with related species are discussed, and a key to the Brazilian species of the series is provided.

Estrutura do componente arbustivo-arbóreo da vegetação em duas áreas de caatinga, no município de Floresta, Pernambuco

Avaliaram-se a composição e estrutura do componente arbustivo-arbóreo da vegetação de duas áreas de caatinga com diferentes histórias de uso, em Floresta, PE. Foram avaliadas 60 parcelas de 20 x 20 m, sendo 40 em área de vegetação secundária, 22 anos após o corte raso (Área I); e 20 parcelas em área com vegetação conservada (Área II). Foi feita a identificação botânica e medidas a circunferência à altura do peito (CAP) e a altura das árvores com CAP > 6,0 cm, estimando os parâmetros de estrutura horizontal e índices de riqueza e diversidade. A vegetação secundária apresentou maior riqueza de espécies, diferindo quanto à estrutura fitossociológica e fisionomia da vegetação conservada. Nas duas áreas, a espécie de maior Valor de Importância foi Poincianella bracteosa, cuja dominância foi maior na Área I, onde Pityrocarpa moniliformis, Piptadenia viridifolia, Senna spectabilis e Croton blanchetianus foram exclusivas. Croton rhamnifolius, Manihot glaziovii e Myracrodruon urundeuva, presentes em ambas as áreas, tiveram maior importância relativa na área conservada. Na área conservada, a vegetação apresentou área basal, altura média e máxima maiores do que na área perturbada, mostrando que a estrutura da vegetação com 22 anos ainda estava em desenvolvimento. Tomando como referência a área basal da Área II e o incremento estimado na área de vegetação secundária, a regeneração em áreas desmatadas exigiria período superior a 40 anos para reestabelecer a estrutura original.

Photosynthetic traits and water use of tree species growing on abandoned pasture in different periods of precipitation in Amazonia

Pasture soils in the Amazon become unsustainable after a short period of use, typically being replaced by emergent secondary vegetation (capoeira). The aim of this research was to investigate the photosynthetic capacity and water use in the most common tree species (Vismia japurensis, Vismia cayennensis, Bellucia grossularioides, Laetia procera, and Goupia glabra) in successional chronosequence. This study was carried out in secondary vegetation area with ages that vary between 1 and 19 years. Responses of gas exchange were determined during different periods of precipitation. The gas exchange decreased with advancing age of the vegetation (1–19 years), except for G. glabra. Negative relationships of PNmax as a function of aging observed for V. japurensis, V. cayennensis, B. grossularioides, and L. procera exhibited r2 equal to 0.59, 0.42, 0.33, and 0.58, respectively. The species of Vismia showed higher values for photosynthetic parameters in relation to other species across the chronosequence. Overall, there were differences in gas exchange only for some species between the different periods of precipitation. Therefore, our results suggest a distinct pattern of photosynthetic responses to species in early succession. Light decrease can exert a decisive role to reduce the photosynthetic rates in secondary succession species. On the other hand, the results of WUE showed weak evidence of changes for the species during dry and rainy periods in the abandoned pasture in central Amazonia.

Evaluation of Growth Cedrela odorata L. in a Secondary Vegetation Area

Evaluation of Growth Cedrela odorata L. in a Secondary Vegetation Area

Estimativa de área de vegetação secundária na Amazônia Legal Brasileira

A vegetação secundária tem funções relevantes para os ecossistemas, tais como a fixação de carbono atmosférico, a manutenção da biodiversidade, o estabelecimento da conectividade entre remanescentes florestais, manutenção dos regime hidrológico e a recuperação da fertilidade do solo. O objetivo deste trabalho é, através de uma abordagem amostral, estimar a área ocupada por vegetação secundária na Amazônia Legal Brasileira (AML) em 2006. A amostragem se baseia em uma abordagem estratificada pelo grau de desflorestamento das cenas LANDSAT-TM que recobrem a AML. Foram selecionadas 26 cenas para o ano de 2006, distribuídas em sete estratos conforme o percentual de desflorestamento, nas quais foram mapeadas as áreas de vegetação secundária a partir de técnicas de classificação de imagens. Foi desenvolvido um modelo multivariado de regressão para estimar a área de vegetação secundária utilizando como variáveis independentes a área de desflorestamento, a área de hidrografia, a estrutura agrária, e área das unidades de conservação. A análise de regressão encontrou um R2 ajustado de 0,84 , e coeficientes positivos para a proporção de hidrografia na imagem (2,055) e para a estrutura agrária (0,197), e coeficientes negativos para o grau de desflorestamento na imagem (-0,232) e para a proporção de Unidades de Conservação na imagem (-0,262). O modelo de regressão estimou uma área de 131.873 km² de vegetação secundária para o ano de 2006. Aplicando uma simulação Monte Carlo foi estimada uma incerteza de aproximadamente 12.445 km² para a área.

Variabilidade espacial de atributos físicos de um argissolo vermelho-amarelo sob pastagem e vegetação secundária em regeneração natural

Este trabalho foi realizado com o objetivo de estudar a variabilidade espacial de atributos físicos de um Argissolo Vermelho-Amarelo sob pastagem e vegetação secundária em regeneração natural. Duas áreas foram escolhidas em uma encosta, com a amostragem de solo à profundidade de 0-0,2 m, com os pontos georreferenciados em uma malha regular de 10x10 m, totalizando 64 pontos em cada área. Foram avaliados o volume total de poros, macroporosidade, microporosidade, densidade do solo, resistência do solo à penetração e umidade do solo em cada ponto. Os atributos estudados na área de pastagem apresentam indicador de compactação do solo pelo pisoteio de animais, com estrutura moderada e forte dependência espacial, com exceção da macroporosidade e a resistência à penetração. Na área de vegetação secundária (VN), somente a macroporosidade não apresenta dependência espacial. O volume total de poros e a densidade do solo apresentam o mesmo padrão espacial na área sob pastagem.

Biomassa acima do solo de espécies herbáceas e subarbustivas com potencial medicinal em uma vegetação secundária.

As espécies herbáceas e subarbustivas com potencial medicinal de ocorrência em uma vegetação secundária, com seis anos de idade, situada no Parque Florestal Quedas do Rio Bonito, Lavras, MG - Brasil, tiveram sua produção de biomassa acima do solo avaliada em 60 unidades amostrais de 0,5 x 0,5 m (0,25 m2). Foram encontradas sete espécies distribuídas em cinco famílias botânicas. Quanto ao hábito das espécies, quatro são herbáceas e três subarbustivas. A produção total da biomassa acima do solo foi de 1740,0 kg.ha-1. Verificou-se que a área de vegetação secundária estudada apresenta potencialidade para o fornecimento de matéria-prima de origem vegetal para uso medicinal.

Land cover and conservation state of a region in the Southern limit of the Atlantic Forest (river Maquiné basin, Rio Grande do Sul, Brazil)

The state of conservation of Atlantic Forest in the Maquiné river basin was assessed using land cover data obtained from Landsat TM 5 satellite imagery (October 1995). The initial analysis examined the distribution of the relative areas of each land-cover type according to landscape slope classes, potential vegetation zones, and a 90 m riparian buffer. Land-cover classes were then regrouped into categories representing "low", "intermediate", and "high" degree of anthropogenic alteration. Results indicate that about 70% of the land cover of the Maquiné river basin has been highly altered as a consequence of replacement of natural forests by agriculture. Presently, a recovery process seems to be underway, contrasting with the historical trend towards deforestation. There are large areas of secondary vegetation in intermediate (34.8%) and advanced successional stages (20.2%), particularly across the range of the montane forest and of forest formations that occur at elevations higher than 800 m (high-montane dense ombrophilous forest and mixed ombrophilous forest). The geographical location at the southern limit of the Atlantic Forest stricto sensu and comparison of the results with data on the state of conservation of the Atlantic Forest in Rio Grande do Sul indicate that the Maquiné river basin is an important area for conservation. Some points regarding future research and conservation management are also discussed.

Community of male Euglossini bees (Hymenoptera: Apidae) in a secondary forest, Alcântara, MA, Brazil.

From September, 92 to August, 93 bee sampling was done in a secondary forest near the Pepital River, in Alcântara, MA, in order to study the local Euglossini fauna. Five aromatic compounds were used: eucaliptol, eugenol, methyl salicylate, vanillin, and benzoate. Four hundred sixty-seven male Euglossini bees were captured, distributed in 4 genus and 19 species. Euglossa was the most abundant and with high diversity (302 specimens and 14 species), followed by Eulaema (121; 3), Eufriesea (41; 1), and Exaerete (3; 1). The species which more frequently visited the bait were Euglossa piliventris (141 specimens; 30.19%), Euglossa cingulata (113; 24.21%), Euglossa ignita (45; 9.64%), Eufrieseapulchra (41; 8.78%), and Euglossa gaianii (33; 7.07%) corresponding to 79.88% of the sampling universe. The bees were active throughout the year, however during the rainy season more activity and diversity were observed. The most attractive essence was eucaliptol (44.32% specimens and 84.21% species). In spite of this study having been done in a forest fragment, a secondary vegetation area smaller than other areas studied in Maranhão, it showed a significant diversity rate. This result reinforces the importance of fragments in the conservation of local bee communities.

The hummingbird community of a lowland Amazonian rainforest

Between October 1987 and September 1989, the British Ornithologists' Union Colombia Expedition recorded 16 species of hummingbird at Matamatá in the Amacayacu National Park, Amazonas, Colombia. Most of these species were resident breeders at the study site although two appeared to be local migrants. Six species of hermit hummingbirds (subfamily Phaethornithinae) occurred at Matamatá; although very similar in general morphology and behaviour, they showed different preferences for habitat, food plants and foraging technique. Hermits were predominant in the forest, but in areas of secondary vegetation and along riverine borders, “typical” hummingbirds (subfamily Trochilinae) were more common. The study site consisted of terra firme and várzea forest and an area of riverine secondary vegetation and contained around 60 species of flowering plants visited by hummingbirds. In contrast with most groups of organisms, hummingbirds and hummingbird‐pollinated plants had similar species diversity in primary forest and secondary habitats. The overall abundance of hummingbirds and flowers was significantly higher in areas of riverine secondary growth. The hummingbird community at Matamatá is remarkably species rich when compared with study sites elsewhere in North and South America. However, random null model comparisons among Amazonian hummingbird communities reveal that they share many characteristics in their structure and show a high degree of species overlap.