9 research outputs found
Management of Brazilian hardwood species (Jatoba and Garapa) wood waste biomass utilization for energy production purposes
ArticleIn the
Federative
Republic of Brazil,
Jatoba (
Hymenaea courbaril
) and Garapa
(
Apuleia
leiocarpa
) trees
are intensively harvested
. The yield of one log is approximately
45
â
55%, which
indicates a
great
amount of produced wood waste biomass.Present research
monitored the suitability of wood waste biomass from Jatoba and Garapa trees for bio
â
briquette
for solid biofuel production.
The research
was focused on chemical parameters,
and
energ
y
potential of such biomass kinds. Jatoba wood waste biomass was used for the
production
of bio
â
briquette fuel and its final mechanical quality was investigated by determination of their
mechanical quality indicators.
Results of chemical analysis (in wet b
asis) exhibited
great
level of
ash content in case of both species (
Jatoba
â
0.31%, Garapa
â
3.02%), as well as high level of
energy potential; net calorific value
equal to 18.92
MJ
kg
â
1
for Jatoba and to
18.39
5
MJ
kg
â
1
for
Garapa. Analysis of elementary
composition proved following levels of oxygen content: J
atoba
â
41.10%, Garapa
â
39.97
%. Mechanical analysis proved bio
â
briquette samples volume
density
Ï equal to
896.34
kg
m
â
3
which indicated quality
bio
â
briquette fuel
, while the
level
of rupture
force R
F occurred at a
lower
level
â
47.05
N
mm
â
1
. Most important quality indicator, the
mechanical durability DU,
unfortunately,
occurred at a
lower
level; DU
=
77.6% compared to the
minimal level of bio
â
briquette fuels intended for commercial sales which must
be >
90%. Overall
analysis proved materials suitability for energy generation purpose with certain limitations which
can improve by changing production parameters of
briquetting
Structure from motion photogrammetry in forestry : a review
AbstractPurpose of ReviewThe adoption of Structure from Motion photogrammetry (SfM) is transforming the acquisition of three-dimensional (3D) remote sensing (RS) data in forestry. SfM photogrammetry enables surveys with little cost and technical expertise. We present the theoretical principles and practical considerations of this technology and show opportunities that SfM photogrammetry offers for forest practitioners and researchers.Recent FindingsOur examples of key research indicate the successful application of SfM photogrammetry in forestry, in an operational context and in research, delivering results that are comparable to LiDAR surveys. Reviewed studies have identified possibilities for the extraction of biophysical forest parameters from airborne and terrestrial SfM point clouds and derived 2D data in area-based approaches (ABA) and individual tree approaches. Additionally, increases in the spatial and spectral resolution of sensors available for SfM photogrammetry enable forest health assessment and monitoring. The presented research reveals that coherent 3D data and spectral information, as provided by the SfM workflow, promote opportunities to derive both structural and physiological attributes at the individual tree crown (ITC) as well as stand levels.SummaryWe highlight the potential of using unmanned aerial vehicles (UAVs) and consumer-grade cameras for terrestrial SfM-based surveys in forestry. Offering several spatial products from a single sensor, the SfM workflow enables foresters to collect their own fit-for-purpose RS data. With the broad availability of non-expert SfM software, we provide important practical considerations for the collection of quality input image data to enable successful photogrammetric surveys
Inventårio mortalidade da Azinheira sobre fotografia aérea digital 2004/2006.
Inventårio NAcional da Mortalidade da Azinheira fotografia aérea digital 2004/2006
Avaliação da morfologia dos sistemas radicais de plantas de regeneração do sobreiro através de imagem digital Evaluation of root systems morphology in young cork oak trees using digital image analysis
O presente trabalho tem como objectivo comparar padrĂ”es de enraizamento, ou seja, a morfologia do sistema radical de ĂĄrvores regeneradas por sementeira com ĂĄrvores plantadas. A evolução dos sistemas radicais pode ter influĂȘncia no crescimento de longo prazo e daĂ a importĂąncia de o monitorizar. Os dados foram recolhidos num povoamento instalado em 1997. A metodologia seguida para avaliar a morfologia do sistema radical foi atravĂ©s de imagem digital. A morfologia do sistema radical e a distribuição das raĂzes nos vĂĄrios horizontes do perfil do solo foi avaliada em oito trincheiras (4 ĂĄrvores plantadas + 4 ĂĄrvores semeadas). Os resultados mostram diferenças significativas, sendo a ĂĄrea do sistema radical das ĂĄrvores plantadas maior do que a das semeadas, nĂŁo se tendo encontrado diferenças significativas no padrĂŁo de enraizamento entre ĂĄrvores plantadas e semeadas.The purpose of this study is to compare rooting patterns, namely root systems morphology of trees planted from seedlings with root systems morphology of seeded trees. The evolution of root systems can influence growth in future therefore it is important to monitor it. Data was collected in a stand installed in 1997. The evaluation of the root morphology was done using digital image analysis. Root system morphology and distribution of roots in different horizons was evaluated in eight trenches (4 trees planted + 4 trees seeded). The results show significant differences showing planted trees larger root area than seeded trees. It wasnât found significant differences in the root system shape between planted and seeded trees