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Live above-and belowground biomass of a Mozambican evergreen forest:a comparison of estimates based on regression equations and biomass expansion factors

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Forest Ecosystems 2016年第1期3卷 1-12页

作者： Tarquinio Mateus Magalhāes Departamento de engenharia florestal Universidade Eduardo MondlaneCampus Universitario

Background： Biomass regression equations are claimed to yield the most accurate biomass estimates than biomass expansion factors （BEFs）. Yet, national and regional biomass estimates are generally calculated based on BEFs, especially when using national forest inventory data. Comparison of regression equations based and BEF-based biomass estimates are scarce. Thus, this study was intended to compare these two commonly used methods for estimating tree and forest biomass with regard to errors and biases. Methods： The data were collected in 2012 and 2014. In 2012, a two-phase sampling design was used to fit tree component biomass regression models and determine tree BEFs. In 2014, additional trees were felled outside sampling plots to estimate the biases associated with regression equation based and BEF-based biomass estimates; those estimates were then compared in terms of the following sources of error： plot selection and variability, biomass model, model parameter estimates, and residual variability around model prediction. Results： The regression equation based below-, aboveground and whole tree biomass stocks were, approximately, 7.7, 8.5 and 8.3 % larger than the BEF-based ones. For the whole tree biomass stock, the percentage of the total error attributed to first phase （random plot selection and variability） was 90 and 88 % for regression- and BEF-based estimates, respectively, being the remaining attributed to biomass models （regression and BEF models, respectively）. The percent bias of regression equation based and BEF-based biomass estimates for the whole tree biomass stock were -2.7 and 5.4 %, respectively. The errors due to model parameter estimates, those due to residual variability around model prediction, and the percentage of the total error attributed to biomass model were larger for BEF models （than for regression models）, except for stem and stem wood components. Conclusions＂ The regression equation based biomass stocks were found to be slightly larg

关键词： Androstachysjohnsonii Prain Mecrusse Root growth Biomass additivity Double sampling Forest biomassinventory Carbon allocation

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Species-specific biomass allometric models and expansion factors for indigenous and planted forests of the Mozambique highlands

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Journal of Forestry Research 2021年第3期32卷 1047-1065页

作者： Tarquinio Mateus Magalhaes Victoria Norberto Cossa Benard Soares Guedes Amélia Saraiva Monguela Fanheiro Departamento de engenharia florestal Faculdade de Agronomia e Engenharia FlorestalUniversidade Eduardo MondlaneCampus UniversitárioEdifício no.1257MaputoRepública de Mocambique Departamento de Sociologia Rural Escola Superior de Desenvolvimento RuralUniversidade Eduardo MondlaneVilankuloRepública de Mocambique

Secondary Miombo woodlands and forest plantations occupy increasing areas in Mozambique,the former due to anthropogenic ***,mainly species of Eucalyptus and Pinus,are being established on sites previously covered by secondary Miombo *** affects the evolution,cycle and spatiotemporal patterns of carbon(C)storage and stocks in forest *** estimation of C storage,which is indispensable for formulating climate change policies on sequestrating CO_(2),requires tools such as biomass models and biomass conversion and expansion factors(BCEF).In Mozambique,these tools are needed for both indigenous forests and *** objective of this study is to fit species-specific allometric biomass models and BCEF for exotic and indigenous tree *** incorporate efficient inter-species variability,biomass equations were fitted using nonlinear mixed-effects *** tree component biomass models had good predictability;however,better predictive accuracy and ability was observed for the 2-predictors biomass model with tree height as a second *** majority of the variability in BCEF was explained by the variation in tree *** species had larger crown biomass per unit of stem diameter and stored larger amounts of biomass per stem ***,due to relatively rapid growth,larger stem diameters,heights,and stand density,the plantations stored more biomass per tree and per unit area.

关键词： Biomass allometry Biomass partitioning Miombo Exotic forest plantations Brachystegia spiciformis Julbernardia globifl ora Eucalyptus Pinus

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Iron toxicity resistance strategies in tropical grasses:The role of apoplastic radicular barriers

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Journal of Environmental Sciences 2019年第4期31卷 257-266页

作者： Advanio Inacio Siqueira-Silva Camilla Oliveira Rios Eduardo Gusmao Pereira Institute of Biological and Health Sciences Federal University of Vicosa (UFV)Campus Florestal Minas Gerais Brazil Federal University of Western Para (UFOPA) University Campus of JurutiPara Brazil Postgradute Program in Management and Conservation of Natural and Agrarian Ecosystems UFV Campus Florestal Florestal Minas Gerais Brazil

The revegetation of mined areas poses a great challenge to the iron ore mining *** initial recovery process in degraded areas might rely on the use of Fe-resistant *** grasses, such as Paspalum densum and Echinochloa crus-galli, show different resistance strategies to iron toxicity; however, these mechanisms are poorly *** Fe-resistance mechanisms and direct iron toxicity as a function of root apex removal were investigated. To achieve this purpose, both grass species were grown for up to 480 hr in a nutrient solution containing 0.019 or 7 mmol/L Fe-EDTA after the root apices had been removed or maintained. Cultivation in the presence of excess iron-induced leaf bronzing and the formation of iron plaque on the root surfaces of both grass species, but was more significant on those plants whose root apex had been removed. Iron accumulation was higher in the roots, but reached phytotoxic levels in the aerial parts as well. It did not hinder the biosynthesis of chloroplastidic pigments. No significant changes in gas exchange and chlorophyll a fluorescence occurred in either grass when their roots were kept intact; the contrary was true for plants with excised root apices. In both studied grasses, the root apoplastic barriers had an important function in the restriction of iron translocation from the root to the aerial plant parts, especially in E. crus-galli. Root apex removal negatively influenced the iron toxicity resistance mechanisms(tolerance in P. densum and avoidance in E. crus-galli).

关键词： Paspalum densum Echinochloa crus-galli Apoplastic barrier Iron toxicity

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Morphological and molecular diversity of arbuscular mycorrhizal fungi in revegetated iron-mining site has the same magnitude of adjacent pristine ecosystems

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Journal of Environmental Sciences 2018年第5期30卷 330-343页

作者： Caroline Krug Vieira Matheus Nicoletti Marascalchi Arthur Vinicius Rodrigues Rafael Dutra de Armas Sidney Luiz Stürmer Universidade Regional de Blumenau(FURB) Programa de Pos-Graduacao em Engenharia Ambiental89030-903 BlumenauSCBrazil Universidade Regional de Blumenau(FURB) Departamento de Ciencias Naturais(DCN)89030-903 BlumenauSCBrazil Uniuersidade Regional de Blumenau(FURB) Programaa de Pos-Graduacao em Engenharia Florestal89030-903 BlumenauSCBrazil Centro Universitario-Catolica de Santa Catarina 89203-005 JoinvilleSCBrazil

Arbuscular mycorrhizal fungi（AMF） are important during revegetation of mining sites, but few studies compared AMF community in revegetated sites with pristine adjacent ecosystems. The aim of this study was to assess AMF species richness in a revegetated iron-mining site and adjacent ecosystems and to relate AMF occurrence to soil chemical parameters. Soil samples were collected in dry and rainy seasons in a revegetated iron-mining site（RA） and compared with pristine ecosystems of forest（FL）, canga（NG）,and Cerrado（CE）. AMF species were identified by spore morphology from field and trap cultures and by LSU r DNA sequencing using Illumina. A total of 62 AMF species were recovered, pertaining to 18 genera and nine families of Glomeromycota. The largest number of species and families were detected in RA, and Acaulospora mellea and Glomus sp1 were the most frequent species. Species belonging to Glomeraceae and Acaulosporaceae accounted for 42%–48% of total species richness. Total number of spores and mycorrhizal inoculum potential tended to be higher in the dry than in the rainy season, except in RA. Sequences of uncultured Glomerales were dominant in all sites and seasons and five species were detected exclusively by DNA-based identification. Redundancy analysis evidenced soil p H,organic matter, aluminum, and iron as main factors influencing AMF presence. In conclusion, revegetation of the iron-mining site seems to be effective in maintaining a diverse AMF community and different approaches are complementary to reveal AMF species, despite the larger number of species being identified by traditional identification of field spores.

关键词： Community structure Glomeromycota Illumina LSU rDNA Spore morphology Taxonomic distinctness index

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Land cover changes and fragmentation in mountain neotropical ecosystems of Oaxaca, Mexico under community forest management

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Journal of Forestry Research 2019年第1期30卷 143-155页

作者： Rafael M~a Navarro Cerrillo Dennis J.Esteves Vieira Susana Ochoa-Gaona Bernardus H.J.de Jong M~a del Mar Delgado Serrano Depto. Ingeniería Forestal Laboratorio de SelviculturaDendrocronología y Cambio Climático.Dendrodat Lab-ERSAF Universidad de Córdoba Depto. de engenharia florestal Faculdade de Engenharia Florestal Laboratório de Sensoriamento Remoto e Geotecnologia Universidade Federal de Mato Grosso Departamento de Ciencias de la Sustentabilidad El Colegio de la Frontera Sur-Unidad Campeche Depto. Economía Sociología y Política Agrarias Grupo de Evaluación y Restauración de Sistemas Agrícolas y Forestales-ERSAF Universidad de Córdoba

Changes in land cover have a direct impact on forest ecosystem goods and services. In this study, changes in land cover in Sierra de Juarez–Oaxaca ecosystems were estimated using a consistent processing of Landsat images and OBIA methodology. Additionally, landscape analyses using FRAGSTAT were conducted. In 2014, Sierra de Juarez–Oaxaca was covered by approximately 84% of forests, mainly pine-oak and cloud forests. After extensive deforestation until 2001, this trend was reversed and the forest cover surface area in 2014 was slightly higher than in 1979. The comparison of the landscape structure of the forested and agricultural lands suggests an increase in habitat heterogeneity. However, interspersion and juxtaposition indices, showing the patch shape by patch area and perimeter, were similar throughout the study period(1979–2014). Social and economic drivers can explain this situation: namely, community organization, forest enterprises, payment for ecosystem services programs, and changes of agricultural activity. Communities in the Sierra of Oaxaca have reforested degraded lands, created community forest enterprises, and preserved the forest under conservation schemes like those proposed by the Mexican payment for ecosystem services programs. However, their sustainable management faces internal challenges and has become highly dependent on political and institutional decisions beyond their control.

关键词： Tropical and temperate forests Social forestry Land uses segmentation OBIA FRAGSTAT

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TRANSIENT ANALYSIS OF COMPOSITE PLATES BY A LOCAL RADIAL BASIS FUNCTIONS-FINITE DIFFERENCE TECHIQUE

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Acta Mechanica Solida Sinica 2012年第1期25卷 22-36页

作者： C.M.C.Roque D.Cunha A.J.M.Ferreira INEGI Faculdade de Engenharia da Universidade do PortoRua Dr.Roberto Frias Departamento de engenharia Mecnica Faculdade de Engenharia da Universidade do PortoRua Dr.Roberto Frias

The use of local numerical schemes,such as finite differences produces much better conditioned matrices than global collocation radial basis functions ***,finite differ-ence schemes are limited to special *** scattered points,a combination of finite differences and radial basis functions would be a possible *** this paper,we use a higher-order shear deformation plate theory and a radial basis function-finite difference technique for predicting the transient behavior of thin and thick composite *** numerical experiments on beams and composite plates,the accuracy and efficiency of this collocation technique is demonstrated.

关键词： meshless beam composite plate

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Growth of Variable Aspect Ratio ZnO Nanorods by Solochemical Processing

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Journal of Materials Science & Technology 2015年第1期31卷 10-15页

作者： Marivone Gusatti Daniel A.R.Souza Nivaldo C.Kuhnen Humberto G.Riella Departamento de engenharia Química e engenharia de Alimentos Programa de Pós-Graduacao em Engenharia Química LABMAC Universidade Federal de Santa Catarina (UFSC) Campus UniversitárioCP 476 Florianópolis Santa Catarina 88040-900 Brazil

In this work,variable aspect ratio（length divided by diameter） zinc oxide nanorods were synthesized through a simple solochemical method by reacting a Zn2+precursor with sodium hydroxide at low reaction *** analysis of the X-ray diffraction data indicated that the samples had hexagonal wurtzite structure and nanometric size *** transmission electron microscopy（TEM） images of the products prepared at60 and 80 ℃ exhibited rod-like architecture,showing that the reaction temperature did not affect the ZnO *** average aspect ratio of the ZnO nanorods decreased from 3.4 to 2.4 when the reaction temperature was raised from 60 to 80 ℃.The samples presented a blue shift in the excitonic absorption compared to ZnO bulk that increased alongside with reaction *** addition,this research investigated the results obtained by varying the concentration of zinc chloride *** the same temperature,it could be verified that when the zinc concentration was increased,the diameter of the ZnO nanorods also slightly increased,and much shorter nanorods were achieved,especially in the reactions performed at 50 and 70 ℃.Finally,the growth mechanism of the ZnO nanostructures was proposed based on the results obtained by changing the zinc precursor concentration and reaction temperature.

关键词： Chemical synthesis ZnO nanorods Growth mechanism

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Increasing analyzable steel thickness for thin layer activation experiments

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Nuclear Science and Techniques 2020年第3期31卷 35-44页

作者： Joao Francisco de Oliveira Antunes Mauro Lucio Borges Lemos Michel de Almeida Franca Julio Cezar Suita Celso Marcelo Franklin Lapa Instituto de engenharia Nuclear Rio de Janeiro 21941-614Brazil Programa de engenharia Nuclear-COPPE/UFRJ Riode Janeiro 21941-450Brazil

The thin layer activation technique(TLA)is very effective in wear analysis for tribological systems where disassembly is costly or *** its development in the 1970s,TLA has been applied through direct irradiation of solid targets using ionizing particle beams to obtain an activation with a specific *** profile is then used to measure wear in a variety of *** experiments rely heavily on how deep the normalized activation *** of 30μm to 50μm are obtained for constant activation by the standard method,which for many experiments is ***,many others would benefit greatly from a 300μm constant activation layer,such as high-performance engines,softer alloys(brakes),and oil transport *** this aim was the goal of this ***,we needed to find an adequate irradiation line for the TLA ***,another technique/system was developed(the Attenuation Wheel),which would bring the depth of constant activation from 50μm to 300μm.

关键词： Thin layer activation Wear Proton beam Attenuation wheel

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Highly electroactive N–Fe hydrothermal carbons and carbon nanotubes for the oxygen reduction reaction

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Journal of Energy Chemistry 2020年第11期29卷 260-270页

作者： R.G.Morais N.Rey-Raap J.L.Figueiredo M.F.R.Pereira Associate Laboratory LSRE-LCM Departamento de Engenharia QuimicaFaculdade de EngenhariaUniversidade do PortoR.Dr.Roberto Frias s/n4200-465PortoPortugal

Glucose-derived carbons were prepared by hydrothermal carbonization of glucose followed by carbonization or activation to obtain carbon materials with different microporosities. These microporous carbons and carbon nanotubes(CNTs) were functionalized with melamine and/or iron(Ⅱ) phthalocyanine(FePc)following three different methodologies:(i) Functionalization with melamine via thermal treatment,(ii)incorporation of the lowest amount of FePc reported in the literature via incipient wetness impregnation followed by thermal treatment and(iii) functionalization with melamine followed by Fe Pc *** chemical and textural characterization of the prepared materials and their electrochemical assessment allowed to understand the role of microporosity in the incorporation of FePc and its effect on the oxygen reduction reaction(ORR). It was observed that FePc was preferentially incorporated inside the porous structure, especially in samples with more developed microporosity. However, functionalization with melamine modified the textural properties and the surface chemistry, favoring the incorporation of FePc on the surface. Regarding the electrochemical performance, the presence of FePc greatly enhanced the electroactivity of the microporous catalysts. An onset potential of 0.88 V and a four-electron pathway were obtained for glucose-derived carbons, whereas the limiting current densities and kinetic current densities rose by 126% and 222%, respectively, in comparison to the base sample. Notwithstanding, the highest electrochemical activity was observed for the sample prepared with CNTs, due to the synergy between the active metal centers and their highly graphitic carbon structure. The electrochemical parameters of CNTFeP csurpass the commercial Pt/C. The half-wave potential is 40 mV higher, the limiting current density increases by 17%, and a negligible production of by-products(< 1%) was observed.

关键词： Iron(Ⅱ)phthalocyanine Hydrothermal carbons Carbon nanotubes Oxygen reduction reaction Electrocatalysis

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Cloning and characterization of gene-resistant analogs(RGAs)involved in rust(Puccinia psidii) resistance in Eucalyptus grandis

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Journal of Forestry Research 2015年第3期26卷 711-718页

作者： Marcelo Luiz Laia Acelino Couto Alfenas Sergio Hermínio Brommonschenkel Shinitiro Oda Eduardo José de Melo Inaê Mariêde Araú jo Silva Janaína Fernandes Gonalves Ariadne Marques Departamento de engenharia florestal Universidade Federal dos Vales do Jequitinhonha e Mucuri DiamantinaMinas Gerais 39100-000 Brazil Departamento de Fitopatologia Universidade Federal de Viosa Viosa Minas Gerais 36570-900 Brazil Suzano Bahia Sul Celulose S/A Suzano So Paulo Brazil

Disease-resistant genes play an important role in defending against a variety of pathogens and insect pests in plants. Most of the disease-resistant genes encode pro- teins with conserved leucine rich repeat and nucleotide binding site domains. In this study, we cloned and char- acterized gene-resistant analogs （RGAs） from Eucalyptus grandis using degenerate PCR, with primers specifically targeting these two domains. The amplified fragments were cloned into the pGEM-T vector and transformed into Escherichia coli. Among the 90 clones obtained, 13 were sequenced and compared with each other and with previ- ously identified gene-resistant diseases. A BLASTX search in GenBank revealed high similarities among the con- served domains of these cloned genes with RGA genes. Some clones, however, showed no significant similarity with DNA sequences in GenBank. Southern blotting ana- lysis identified several polymorphic RFLP loci between distinct genotypes. However, none of them co-segregated with the Puccinia psidii Winter resistance gene 1 （Ppr1） in a population study.

关键词： Cloning Conserved domains RGAs Rust Eucalyptus

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