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Tree structure and diversity of lowland Atlantic forest fragments：comparison of disturbed and undisturbed remnants

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Journal of Forestry Research 2016年第3期27卷 605-609页

作者： Fabricio Alvim Carvalho Joao Marcelo Alvarenga Braga Marcelo Trindade Nascimento departamento de Botanica Universidade Federal de Juiz de Fora. Campus Universitario s/n Sao PedroJuiz de Fora-MG 36036-900 Brazil instituto de pesquisas do jardim botanico do Rio de Janeiro. Rio de Janeiro-RJ Brazil Laboratorio de Ciencias Ambientais CBB Universidade Estadual do Norte Fluminense Campos dos Goytacazes-RJ 28013-602 Brazil

This study describes the tree community structure of three moist lowland Atlantic Forest fragments in Rio de Janeiro State, southeastern Brazil. Two fragments were disturbed and an undisturbed one was used as reference. Our hypothesis was that disturbed fragments show distinct structural patterns in comparison with undisturbed stands due to past disturbance practices and forest fragmentation. Four 100 ×5 m sampling plots were demarcated in each fragment and all live and dead trees with DBH C 5 cm were located, measured and identified. The results supported our hypothesis, due to the high values found for standing dead trees, an increase of dominance of a few pioneer species, lower values of large trees and species richness in disturbed fragments in comparison with the undisturbed one. The advanced fragmentation process in the Southern Brazilian lowland areas and the high species richness in undisturbed areas highlight these forest fragments as priority areas for conservation and management.

关键词： Phytosociology Tree community Forestfragmentation . Hotspot Brazil

The Harvesting of the Endangered Palm Euterpe edulis in the Brazilian Atlantic Forest: The Case of Linear Canopy Openings

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Journal of Geoscience and Environment Protection 2023年第12期11卷 151-162页

作者： Pablo José Francisco Pena Rodrigues Mariana de Andrade Iguatemy Talita Reis instituto de pesquisas jardim botanico do Rio de Janeiro Rua Pacheco Le&#227o Rio de Janeiro Brazil

The palm Euterpe edulis was historically very exploited by humans and even today, many individuals are cut down by collectors to harvest the edible palm hearts. The ecological aspects of this anthropogenic pressure and its related effects are poorly understood. Here we investigate if linear canopy openings in a fragment of Brazilian Atlantic Forest can cause edge effects and facilitate predatory harvesting by humans. We sampled in Tinguá Biological Reserve (Southeastern Brazil) native palm populations at forest edges adjacent to two linear canopy openings, and in the forest interior far from any edge. Our 8-year monitoring showed that the linear canopy openings negatively affected the palm populations reducing its density and regeneration mainly on edges, but no local extinction was observed. Thus, the direct human impact from harvesting, adverse survival conditions on edges and interspecific competition causes population declines with no local extinction, so this suggests that E. edulis may resist even under strong anthropogenic pressure.

关键词： Extinction Exploitation Forest Product Species Survival Sustainability

does Linear Canopy Openings in a Lowland Atlantic Tropical Forest Cause Edge Effects on Seedling Communities?

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Open Journal of Ecology 2014年第15期4卷 945-949页

作者： Pablo J. F. Pena Rodrigues Mariana A. Iguatemy Marcelo T. Nascimento instituto de pesquisas jardim botanico do Rio de Janeiro Rio de Janeiro-RJ Brazil Universidade Estadual do Norte Fluminense Darcy Ribeiro Campos dos Goytacazes-RJ Brazil

Edge effects and linear canopy openings may change ecological patterns and processes on forests. Here we investigate if these openings in a lowland Brazilian Atlantic forest cause edge effects on seedlings. We sampled seedling communities at forest edges near to two linear canopy openings (gas pipeline and power line) and in interiors far from edges. Comparisons between the seedling communities were performed to access edge effects. density and basal area patterns were compared using, hierarchical two-way ANOVAs and the number of newly germinated seedlings, mortality and resprouts were compared by one-way ANOVAs. The results showed that edge effects of linear canopy openings affect seedling communities leading to low densities on edges that showed less favorable conditions for arrival, establishment and initial survival. The basal area patterns were not affected by edge effects apparently by the resistance of the seedlings that have more than 4 mm diameter. Therefore, linear canopy openings caused edge effects, which determine low seedling densities on edges. However this pattern is not due to increase mortality on these edges, but probably caused by the reduction on germination and establishment.

关键词： Forest Regeneration Fragmentation Disturbance Human-Modified Habitats Secondary Forests

Leaf Anatomy of Prosthechea moojenii(Pabst)*** and *** Cath.&***(Orchidaceae)as an Approach to Taxonomy of Species Occurring in Biomes Cerrado and Atlantic Forest of the Bahia

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American Journal of Plant Sciences 2012年第12期3卷 1752-1758页

作者： Filipe de Castro Seixas Silvana Helena Nascimento Monteiro Lazaro Benedito da Silva Kelly Regina Batista Leite instituto de Biologia Departamento de BotanicaLaboratório de Anatomia Vegetal e Identificacao de MadeirasCampus Univer-sitário de OndinaUniversidade Federal da BahiaSalvadorBrasil instituto de Pesquisa jardim botanico do Rio de Janeiro Uni-dade de Botanica SistemáticaRio de JaneiroBrasil

Prosthechea is a neotropical genus, belonging to the family Orchidaceae. The Brazil recorded 32 species of the genus of which nine occur in the state of Bahia, including P. silvana and P. moojenii. The first, P. silvana is epiphytic, endemic Atlantic Forest areas of South and Southeast of the Bahia and morphologically similar to P. moojenii, rupicolous species considered endemic to the Chapada Diamantina. There are doubts whether these two species are really distinct, because they differ only as to the way of life and aspects related to the size of the inflorescence and floral structure. Thus the anatomical study of these two species, emerges as a tool that aims to investigate the delimitation of these taxa. For this study, the sheet was cut freehand with a razor blade to obtain cross sections and treated by chemical means to obtain paradermic sections, all the material was stained with safranine/Astra blue (safrablau) and safranin, respectively, and the sections were then mounted between a semipermanent and cover slipped slides. The results allowed to distinguish P. silvana of the P. moojenii through the following characteristics observed in the leaf (thickening of the cell walls of epidermal cells, amount and disposition of sclerenchyma fibers and fiber arrangement of vascular and vascular bundles in the mesophyll) and root (number of arcs of xylem and phloem, thickening of cells median cortex), infers taxonomic characters for the genus. The data indicated anatomical distinction between the two species studied here of the Prosthechea, however, suggest the anatomical analysis of other organs to reproductive and vegetative.

关键词： Laeliinae Flora of Bahia Velamen Endemism

Medicinal Plants Used to Treat Neurological Disorders in West Africa: A Case Study with Guinea-Bissau Flora

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American Journal of Plant Sciences 2012年第7期3卷 1028-1036页

作者： Maria M. Romeiras Maria Cristina Duarte Bucar Indjai Luís Catarino instituto de Investigacao Científica Tropical Jardim Botanico TropicalTravessa Conde da Ribeira 7LisboaPortugal Universidade de Lisboa BioFIGFaculdade de CiênciasCampo GrandeLisboaPortugal Universidade do Porto CIBIOCentro de Investigacao em Biodiversidade&Recursos GenéticosVairaoPortugal INEP Instituto Nacional de Estudos e PesquisaCom-plexo escolar 14 de NovembroC.P.112BissauGuiné-Bissau

The sub-Saharan region holds a wide variety of indigenous plant species, still offering the possibility to discover very interesting new natural products with potential therapeutic value. Most of the African population depends on traditional medicine for primary health care, however, neurological disorders are often not considered as common diseases and many people with mental illnesses, like epilepsy, are severely affected by health-related stigma and discrimination. Epilepsy is the most common serious chronic brain disorder, estimated to affect at least 10 million people in Africa. Guinea-Bissau is located in West Africa, and its population is mainly rural with very few health services available. Since the earliest times, Guinea-Bissau flora has constituted the main source of materials used in folk medicine and the local population, who is well versed in the uses of these plants and their properties. The aim of this study was to document the existing knowledge and practices related to the treatment of neurological disorders, namely epilepsy and seizures, in Guinea-Bissau and in other West African countries. The results presented from this study provide information not only on the specific plants used to treat neurological disorders, but also on social knowledge brought in by various ethnic groups, each one having its own culture, beliefs and ways of nature appropriation. Taking into account the existing knowledge on the medicinal properties of plants for treatment of neurologic disorders, it is believed that research in the areas of ethnomedicine and ethnopharmacology in Guinea-Bissau can bring promising results capable of adding value to the very rich natural resources of this country of West Africa.

关键词： West Africa Medicinal Plants Ethnobotany Epilepsy Guinea-Bissau

Predicting the dynamics of a native Araucaria forest using a distance- independent individual tree-growth model

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Forest Ecosystems 2016年第3期3卷 231-241页

作者： Enrique Orellana Afonso Figueiredo Filho Sylvio Pellico Netto Jerome Klaas Vanclay Midwest State University-UNICENTRO-PR PR 153 Km 7 Riozinho IratiParana 84500-000 Brazil Federal University of Parana UFPR. Av. Pref. Lothario Meissner 900 Jardim Botanico Curitiba Parana 80210-170 Brazil Southern Cross University (SCU) PO Box 157 Lismore NSW Australia

Background： In recent decades, native Araucaria forests in Brazil have become fragmented due to the conversion of forest to agricultural lands and commercial tree plantations. Consequently, the forest dynamics in this forest type have been poorly investigated, as most fragments are poorly structured in terms of tree size and diversity. Methods; We developed a distance-independent individual tree-growth model to simulate the forest dynamics in a native Araucaria forest located predominantly in southern Brazil. The data were derived from 25 contiguous plots （1 ha） established in a protected area left undisturbed for the past 70 years. The plots were measured at 3-year intervals from their establishment in 2002. All trees above a l O-cm diameter at breast height were tagged, identified as to species, and measured. Because this forest type comprises hundreds of tree species, we clustered them into six ecological groups： understory, subcanopy, upper canopy shade-tolerant, upper canopy light-demanding, pioneer, and emergent. The diameter increment, survival, and recruitment sub-models were fitted for each species group, and parameters were implemented in a simulation software to project the forest dynamics. The growth model was validated using independent data collected from another research area of the same forest type. To simulate the forest dynamics, we projected the species group and stand basal areas for 50 years under three different stand-density conditions： low, average, and high. Results： Emergent species tended to grow in basal area, irrespective of the forest density conditions. Conversely, shade-tolerant species tended to decline over the years. Under low-density conditions, the model showed a growth tendency for the stand basal area, while under average-density conditions, forest growth tended to stabilize within 30 years. Under high-density conditions, the model indicated a decline in the stand basal area from the onset of the simulation, suggesting that und

关键词： Forest succession Species group Araucafia angustifolia

Priority areas for watershed service conservation in the Guapi-Macacu region of Rio de Janeiro,Atlantic Forest,Brazil

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Ecological Processes 2014年第1期3卷 95-115页

作者： Vanesa Rodriguez Osuna Jan Borner Udo Nehren Rachel Bardy Prado Hartmut Gaese Jurgen Heinrich Center for development Research(ZEF) Department of Economic and Technological ChangeUniversity of BonnWalter-Flex-Str.353117 BonnGermany Institute for Technology and Resources Management in the Tropics and Subtropics(ITT) Cologne University of Applied SciencesBetzdorfer Str.250679 CologneGermany Empresa Brasileira de Pesquisa Agropecuária(EMBRAPA Soils) Brazilian Enterprise for Agricultural ResearchGeotechnologies and Environmental MonitoringRua Jardim BotanicoCEP 22460-000 Rio de JaneiroBrazil Institute for Geography Department of Physical GeographyUniversity of LeipzigJohannisallee 19a04103 LeipzigGermany

Introduction:Land use intensification and urbanisation processes are degrading hydrological ecosystem services in the Guapi-Macacu watershed of Rio de Janeiro.A proposal to pay farmers to restore natural watershed services might be an alternative to securing the water supply in the long-term for the around 2.5 million urban water users in the study *** study quantifies the costs of changing current land use patterns to enhance watershed services and compares these costs to the avoided costs associated with water treatment for public ***:We use farm-household data to estimate the opportunity costs of abandoning current land uses for the recovery of natural vegetation;a process that is very likely to improve water quality in terms of turbidity due to reduced inputs from *** cost estimates are extrapolated to the watershed scale based on remote sensing land use classifications and vulnerability analysis to identify priority zones for watershed management *** assess the potential demand for watershed services,we analyse water quality and treatment cost data from the main local water treatment ***:Changing agricultural land uses for watershed services provision generally comes at high opportunity costs in our study area near to the metropolis of Rio de *** low cost watershed conservation options do exist in the livestock production *** options have the potential to directly reduce the amount of sediments and nutrients reaching the water bodies,and in turn decrease the costs of treatment needed for drinking *** cover changes at the scale needed to improve water quality will,nonetheless,likely exceed the cost of additional investments in water ***:The state water utility company’s willingness to pay for watershed services alone will not be enough to induce provision of additional watershed *** conclude that monetary incentives conditioned on specific adjustme

关键词： Water services Drinking water treatment Water quality Incentive-based watershed management

New In Vitro Studies on the Bioprofile of Genista tenera Antihyperglycemic Extract

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Natural Products and Bioprospecting 2015年第6期5卷 277-285页

作者： Daniela Batista Pedro L.Falé Maria L.Serralheiro Maria E.Araújo Paulo J.A.Madeira Carlos Borges Isabel Torgal Margarida Goulart Jorge Justino Alice Martins Amélia P.Rauter Centro de Química e Bioquímica Faculdade de CiênciasUniversidade de LisboaCampo Grande1749-016 LisbonPortugal Institute of Pharmaceutical Science King’s College London150 Stamford StreetLondon SE19NHUK Escola Superior Agrária de Santarém Quinta do Galinheiro2001-904 SantarémPortugal

The inhibition of a-glucosidase and glucose-6-phosphatase,two enzymes involved in the carbohydrate metabolism,is an important target to control glycaemia on individuals with type 2 *** this work we report for the first time the inhibition of both enzymes by the antihyperglycemic n-butanol extract from Genista tenera(Fabaceae).This extract decreased a-glucosidase and glucose-6-phosphatase activities to 0.97 and 80.25%,respectively,being more effective than acarbose,and phlorizin,the positive controls,which reduced enzymes activities only to 17.39 and 96.06%.Once inflammation and oxidative stress are related to diabetic impairments,the anti-inflammatory activity of the extract was also evaluated,through its inhibitory activity over COX-1 enzyme(47.5%inhibition).Moreover,after induction of oxidative stress by UV radiation,the viability of irradiated rat liver hepatoma cells exposed to the extract was significantly higher(67.82%)than that promoted by ascorbic acid,the positive control(45.05%).In addition,the stability of the extract under gastrointestinal conditions was evaluated by HPLC–DAD-ESI–MS/*** diglycosides were identified as the main constituents of the extract,and no alterations in the chemical composition nor in the antioxidant activity were observed after in vitro digestion with artificial gastric and pancreatic juices.

关键词： a-Glucosidase inhibition In vitro digestion HPLC-DAD-ESI-MS/MS Antioxidant activity Flavonoid glycosides

Why Sustainable Porous Carbon Should be Further Explored as Radar-Absorbing Material? A Comparative Study with Different Nanostructured Carbons

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Journal of Renewable Materials 2024年第10期12卷 1639-1659页

作者： Alan F.N.Boss Manuella G.C.Munhoz Gisele Amaral-Labat Rodrigo G.A.Lima Leonardo I.Medeiros Nila C.F.L.Medeiros Beatriz C.S.Fonseca Flavia L.Braghiroli Guilherme F.B.Lenz e Silva department of Metallurgical and Materials Engineering University of de São PauloAvenida Mello MoraesCidade UniversitáriaSão PauloSP 05508-030Brazil Coordination of Applied Research and Technological development National Institute for Space ResearchAvenida dos AstronautasJardim da GranjaSão Josédos CamposSP 12227-010Brazil department of Exact and Technological Sciences Santa Cruz State UniversityRodovia Jorge Amadokm16IlhéusBA 45662900Brazil Institut de recherche sur les forêts Universitédu Québec en Abitibi-TémiscamingueRouyn-Noranda445 Bd de l’UniversitéRouyn-NorandaQC J9X 5E4Canada

Radar Absorbing Materials(RAM)are a class of composites that can attenuate incident electromagnetic waves to avoid radar *** carbon allotropes that have the potential to be used as RAM are either carbon nano-tubes(CNTs),graphene,carbon black(CB)and ultimately,sustainable porous carbon(SPC).Here,black wattle bark waste(following tannin extraction)was used as a sustainable source to produce SPC made from biomass *** was characterized and used as afiller for a silicone rubber matrix to produce aflexible *** elec-tromagnetic performance of this composite was compared with composites made with commercial CB and CNT through reflection loss(RL),where-10 dB is equivalent to 90%of *** composites were evaluated in single-layer,double-layer,and as radar absorbing structures(RAS)with the aim of improving their effective absorption bandwidth(EAB)performances and a reduction in *** CNT composite presented a RL of-26.85 dB at 10.89 GHz and an EAB of 2.6 GHz with a 1.9 mm thickness,while the double-layer structures using CNT and SPC provided a RL of-19.74 dB at 10.75 GHz and an EAB of 2.51 ***,the double-layer structures are~42%cheaper than the composite using only CNT since less material is ***,the largest EAB was achieved with a RAS using SPC,reaching~2.8 GHz and a RL of-49.09 dB at 10.4 ***,SPC made of black wattle bark waste can be a competitive,alternative material for use as RAM and RAS since it is cheaper,sustainable,and suitable for daily life uses such as absorbers for anechoic chambers,sensors,and elec-tromagnetic interference shields for electronics,wallets,vehicles,and others.

关键词： Microwave absorption material tannin waste dielectric constant carbon composite reflectivity