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Análise do uso da tecnologia laser aerotransportado para inventários florestais em plantios clonais de Eucalyptus sp no sul da Bahia / Analysis of the airborne laser scanning technology use for forest inventories in cloned Eucalyptus sp plantations in the southern Bahia.Zonete, Matheus Felipe 19 June 2009 (has links)
A aplicação da tecnologia LASER aerotransportado (ALS) para realização de inventários florestais, tem se apresentado como excelente alternativa para a área de planejamento florestal, principalmente pelos ótimos resultados em termos de precisão das estimativas, pelas facilidades de uso e demais produtos e benefícios advindos do sobrevôo com o LASER. A evolução e o menor custo das tecnologias GPS e Sistemas de Medição Inercial têm sido o principal fator de sucesso para a aplicação da tecnologia ALS. Vários trabalhos de análise da tecnologia LASER aerotransportado, em inventários florestais, alguns até mesmo em escalas comerciais (NAESSET, 2007), têm sido realizados principalmente na Europa e no Canadá. Os resultados têm sido muito atraentes, dentre os quais se destacam as estimativas de volume e de área basal que têm apresentado erros de no máximo 8,4%, dependendo das configurações da área amostrada. Sendo assim, este trabalho teve por objetivo analisar o uso da tecnologia ALS para a realização de inventários florestais em níveis de parcela e talhão em plantios clonais de Eucalyptus sp, no sul do estado da Bahia. Para tanto foram realizados levantamentos de campos que permitiram a estimação de parâmetros como área basal, altura de árvores média e das dominantes e volume, em parcelas circulares de treze metros de raio, nas quais foram coletados o diâmetro de todas as árvores e a altura de uma a cada sete árvores da parcela. A área sobrevoada para coleta dos dados LASER foram duas faixas de aproximadamente 2x20km. Os dados LASER foram processados para se obter os percentís das observações ALS nos níveis 10 (f_h10), 30 (f_h30), 50 (f_h50), 70 (f_h70) e 90 (f_h90), bem como a densidade de pontos nos respectivos percentís (f_p10, f_p30, f_p50, f_p70 e f_p90), e a altura média (f_havg) e o desvio padrão (f_hstd) desses pontos. Essas estatísticas foram utilizadas em modelos de regressão para estimar diâmetro médio, altura média, altura dominante, área basal e volume das parcelas amostradas. Para o volume, uma avaliação exploratória de diferentes combinações de variáveis permitiu a definição das relações mais promissoras e a utilização dessas variáveis mais promissoras no ajuste de modelos já consagrados na área de biometria e inventário florestal. As observações ALS que melhor ajustaram diâmetro médio foram f_h30 e f_p30, com R²=0,88 e RQEM%=0,0004; para altura média, f_h10 e f_h90 geraram boas estimativas, com R²=0,94 e RQEM%=0,0003, enquanto que para altura dominante, as melhores estimativas foram obtidas com f_h90, apresentando R²=0,96 e RQEM%=0,0003; e para área basal, os melhores ajustes usaram idade, f_h10 e f_havg, sendo R²=0,92 e RQEM%=0,0016. No caso de volume, os dois melhores modelos exploratórios apontam para o uso de idade, f_h30 e f_p90, em ambos os casos, e ambos com R² entre 0,94 e 0,95 e RQEM% entre 0,002 e 0,003. Já, dentre os modelos biométricos testados, os melhores foram os de Schumacher ajustado com idade e f_h90; Clutter ajustado com idade, f_havg e f_h70; e de Buckman ajustado com idade, f_havg e f_h10. / The application of the airborne laser scanning (ALS) technology for forest inventories execution, have been presented as an excellent alternative to the forest planning area, particularly by the excellent results in terms of accuracy of the estimates, by the facilities of usage and other products and benefits derived from LASER overflight. The technology evolution and lower cost for GPS and Inertial Measurement Units have been the main factor of the success for ALS technology application. Several studies of ALS technology analysis in forest inventories, some even in commercial scales (NAESSET, 2007), have been conducted mainly in Europe and Canada. The results have been very attractive, among which there are the volume and basal area estimates which have made errors of up to 8.4% depending on the settings of the sampled area. Thus, this study aimed to examine the use of the ALS technology for forest inventories executions at plot and stands levels in clonal Eucalyptus sp plantations in the south of Bahia state. Field surveys were conducted to provide the parameters estimation such as diameter, tree heights, basal area and volume in circular plots of thirteen-meter radius, which were the diameter of all trees and height of a the seven trees of each plot. The overflown areas for LASER data collection were two bands of approximately 2x20km. LASER data were processed to obtain the percentiles of the ALS observations in the following levels 10 (f_h10), 30 (f_h30), 50 (f_h50), 70 (f_h70) e 90 (f_h90), and 90 (f_h90) and the density of points in the respective percentiles (f_p10, f_p30, f_p50, f_p70 and f_p90), the average height of the points (f_havg) and the standard deviation (f_hstd). These statistics were used in the regression models to estimate mean diameter, mean height, dominant height, basal area and volume of the sampled plots. For the volume, an exploration of different combinations of the variables supported the definition of the most promising relations and most promising use of these variables in the set of models already established in the biometrics and forest inventory area.The ALS observations that better fit to the average diameter were f_h30 and f_p30, resulting in a R²=0.88 and RQEM%=0.0004; for the average height, f_h10 and f_h90 generate good estimates, having R²=0.94 and RQEM%=0. 0003, therefore for the dominant height, the best estimates were obtained with f_h90, showing R²=0.96 and RQEM%=0.0003. For the basal area, the best fit used age, f_h10 and f_havg, presenting a R²=0.92 and RQEM%=0.0016. In the volume case, the two best exploratory models point to the use of age, f_h30 and f_p90, both with R ² between 0.94 and 0.95 and RQEM% between 000.2 and 000.3. Among the biometric tested models, the best were Schumacher fitted by age and f_h90; Clutter fitted by age, f_havg and f_h70; Buckman fitted by age, f_havg and f_h10.
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Strukturella förändringar i Östergötlands skogar : En jämförelse mellan år 1927 och 1983–2017 / Structural Changes in Swedish Boreo-nemoral Forests : A Comparison Using Data from 1927 and 1983-2017Lindkvist, Tilda January 2018 (has links)
Humans have affected the Swedish forests for a long time, mainly through agriculture and forestry. Since the beginning of the 20th century, a lot of changes have taken place in forest policy, which have affected the structures of our forests, such as tree age, size and species distributions. By using information from different types of historical data, we can increase our understanding of the earlier structures of forests and how to manage them in the future. This study investigated changes in annual growth and changes in age, diameter, height and tree species distribution in the forests of Östergötland from year 1927 to the period 1983-2017, using data from the Swedish National Forest Inventory. Six tree species where used, Picea spp, Pinus spp, Quercus robur, Betula spp, Alnus spp and Populus tremula. There was an increase in the proportion of Picea spp, and a decrease in the proportion of Pinus spp since 1927. The proportion of deciduous trees also increased but not as much. Interestingly, the proportion of Betula spp had fallen since 1927, but the now larger proportion of young trees indicate that the proportion of Betula spp is increasing again. Q. robur, P. tremula, Picea spp and Pinus spp also had a larger proportion of younger trees in the more recent period. There was a significantly higher proportion of tall trees during the latter period for all tree species. For growth rate in width, the results varied among tree species. For Betula spp it had decreased and for Q. robur it had increased. For the coniferous trees there was hardly any difference between the periods. Overall, the results show that Östergötland's forests have been influenced by forestry and increased ungulate populations since the first inventory 1927 and that there have been changes in the composition of the forests. / Människan har länge påverkat de svenska skogarna. Sedan 1900-talets början har en hel del förändringar skett inom skogspolitiken, vilket har påverkat bland annat skogarnas ålder- och storleksfördelning, samt trädslagsfördelning. Genom att använda information från olika typer av historiska data kan vi öka vår förståelse om hur skogar såg ut förr och vad som har påverkat dem. Denna studie undersökte skillnader i tillväxt, höjd-och diameterfördelning, samt åldersfördelning i Östergötlands skogar från år 1927 till perioden 1983–2017, med hjälp av data från riksskogstaxeringen. Sex trädslag användes; gran (Picea spp), tall (Pinus spp), ek (Quercus robur), björk (Betula spp), al (Alnus spp) och asp (Populus tremula). En kraftig ökning av andelen gran hade skett sedan 1927, medan andelen tall hade minskat. För lövträden hade det endast skett en liten ökning i andel. Intressant var också att andelen björk hade minskat sedan 1927 och att andelen björkar yngre än 50 år var större den senare perioden, vilket indikerar att björkens andel kan vara på väg att öka igen. Ek, asp, gran och tall hade också en större andel yngre träd under den senare perioden. För alla trädslag fanns det en betydligt mindre andel höga träd år 1927. För årlig tillväxt i bredd varierade resultaten trädslagen emellan. För björk hade årsringsbredden minskat sedan 1927, medan den hade ökat för ek. För barrträden var det knappt någon skillnad mellan perioderna. Resultaten visar att Östergötlands skogar har påverkats mycket av skogsbruket, samt klövviltsbete, sedan 1927 och att det har skett flera strukturella förändringar i skogarnas sammansättning.
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Predicting time-since-fire from forest inventory data in Saskatchewan, CanadaSchulz, Rueben J. 05 1900 (has links)
Time-since-fire data are used to describe wildfire disturbances, the major disturbance type in the Boreal forest, over a landscape. These data can be used to calculate various parameters about wildfire disturbances, such as size, shape and severity. Collecting time-since-fire data is expensive and time consuming; the ability to derive it from existing forest inventory data would result in availability of fire data over larger areas. The objective of this thesis was to explore the use of forest inventory information for the prediction of time-since-fire data in the mixedwood boreal forests of Saskatchewan.
Regression models were used to predict time-since-fire from forest inventory variables for each inventory polygon with a stand age. Non-water polygons with no stand age value were assigned values from neighbouring polygons, after splitting long polygons that potentially crossed many historic fire boundaries. This procedure filled gaps that prevented polygons from being grouped together in latter analysis. The predicted time-since-fire ages were used to generate wildfire parameters such as age-class distributions and fire cycle. Three methods were examined to group forest inventory polygons together to predict fire event polygons: simple partitions, hierarchical clustering, and spatially constrained clustering. The predicted fire event polygons were used to generate polygon size distribution wildfire metrics.
I found that there was a relationship between time-since-fire and forest inventory variables at this study site, although the relationship was not strong. As expected, the strongest relationship was between the age of trees in a stand as indicated by the inventory and the time-since-fire. This relationship was moderately improved by including tree species composition, harvest modification value, and the ages of the surrounding polygons. Assigning no-age polygons neighbouring values and grouping the forest inventory polygons improved the predicted time-since-fire results when compared spatially to the observed time-since-fire data. However, a satisfactory method of comparing polygon shapes was not found, and the map outputs were highly dependent on the grouping method and parameters used. Overall it was found that forest inventory data did not have sufficient detail and accuracy to be used to derive high quality time-since-fire information.
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Estimating forest structural characteristics with airborne lidar scanning and a near-real time profiling laser systemsZhao, Kaiguang 15 May 2009 (has links)
LiDAR (Light Detection and Ranging) directly measures canopy vertical
structures, and provides an effective remote sensing solution to accurate and spatiallyexplicit
mapping of forest characteristics, such as canopy height and Leaf Area Index.
However, many factors, such as large data volume and high costs for data acquisition,
precludes the operational and practical use of most currently available LiDARs for
frequent and large-scale mapping. At the same time, a growing need is arising for realtime
remote sensing platforms, e.g., to provide timely information for urgent
applications. This study aims to develop an airborne profiling LiDAR system, featured
with on-the-fly data processing, for near real- or real- time forest inventory. The
development of such a system involves implementing the on-board data processing and
analysis as well as building useful regression-based models to relate LiDAR
measurements with forest biophysical parameters.
This work established a paradigm for an on-the-fly airborne profiling LiDAR
system to inventory regional forest resources in real- or near real- time. The system was
developed based on an existing portable airborne laser system (PALS) that has been
previously assembled at NASA by Dr. Ross Nelson. Key issues in automating PALS as
an on-the-fly system were addressed, including the design of an archetype for the system
workflow, the development of efficient and robust algorithms for automatic data
processing and analysis, the development of effective regression models to predict forest
biophysical parameters from LiDAR measurements, and the implementation of an
integrated software package to incorporate all the above development. This work exploited the untouched potential of airborne laser profilers for realtime
forest inventory, and therefore, documented an initial step toward developing
airborne-laser-based, on-the-fly, real-time, forest inventory systems. Results from this
work demonstrated the utility and effectiveness of airborne scanning or profiling laser
systems for remotely measuring various forest structural attributes at a range of scales,
i.e., from individual tree, plot, stand and up to regional levels. The system not only
provides a regional assessment tool, one that can be used to repeatedly, remotely
measure hundreds or thousands of square kilometers with little/no analyst interaction or
interpretation, but also serves as a paradigm for future efforts in building more advanced
airborne laser systems such as real-time laser scanners.
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The effect of plot co-registration error on the strength of regression between LiDAR canopy metrics and total standing volume in a Pinus radiata forestSlui, Benjamin Thomas January 2014 (has links)
Background: The objective of this study was to verify the effect that plot locational errors, termed plot co-registration errors, have on the strength of regression between LiDAR canopy metrics and the measured total standing volume (TSV) of plots in a Pinus radiata forest.
Methods: A 737 hectare plantation of mature Pinus radiata located in Northern Hawkes Bay was selected for the study. This forest had been measured in a pre-harvest inventory and had aerial LiDAR assessment. The location of plots was verified using a survey-grade GPS. Least square linear regression models were developed to predict TSV from LiDAR canopy metrics for a sample of 204 plots. The regression strength, accuracy and bias was compared for models developed using either the actual (verified) or the incorrect (intended) locations for these plots. The change to the LiDAR canopy metrics after the plot co-registration errors was also established.
Results: The plot co-registration error in the sample ranged from 0.7 m to 70.3 m, with an average linear spatial error of 10.6 m. The plot co-registration errors substantially reduced the strength of regression between LiDAR canopy metrics and TSV, as the model developed from the actual plot locations had an R2 of 44%, while the model developed from the incorrect plot locations had an R2 of 19%. The greatest reductions in model strength occurred when there was less than a 60% overlap between the plots defined by correct and incorrect locations. Higher plot co-registration errors also caused significant changes to the height and density LiDAR canopy metrics that were used in the regression models. The lower percentile elevation LiDAR metrics were more sensitive to plot co- registration errors, compared to higher percentile metrics.
Conclusion: Plot co-registration errors have a significant effect on the strength of regressions formed between TSV and LiDAR canopy metrics. This indicates that accurate measurements of plot locations are necessary to fully utilise LiDAR for inventory purposes in forests of Pinus radiata.
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Estimation of individual tree metrics using structure-from-motion photogrammetry.Miller, Jordan Mitchell January 2015 (has links)
The deficiencies of traditional dendrometry mean improvements in methods of tree mensuration are necessary in order to obtain accurate tree metrics for applications such as resource appraisal, and biophysical and ecological modelling. This thesis tests the potential of SfM-MVS (Structure-fromMotion with Multi-View Stereo-photogrammetry) using the software package PhotoScan Professional, for accurately determining linear (2D) and volumetric (3D) tree metrics. SfM is a remote sensing technique, in which the 3D position of objects is calculated from a series of photographs, resulting in a 3D point cloud model. Unlike other photogrammetric techniques, SfM requires no control points or camera calibration. The MVS component of model reconstruction generates a mesh surface based on the structure of the SfM point cloud.
The study was divided into two research components, for which two different groups of study trees were used: 1) 30 small, potted ‘nursery’ trees (mean height 2.98 m), for which exact measurements could be made and field settings could be modified, and; 2) 35 mature ‘landscape’ trees (mean height 8.6 m) located in parks and reserves in urban areas around the South Island, New Zealand, for which field settings could not be modified.
The first component of research tested the ability of SfM-MVS to reconstruct spatially-accurate 3D models from which 2D (height, crown spread, crown depth, stem diameter) and 3D (volume) tree metrics could be estimated. Each of the 30 nursery trees was photographed and measured with traditional dendrometry to obtain ground truth values with which to evaluate against SfM-MVS estimates. The trees were destructively sampled by way of xylometry, in order to obtain true volume values. The RMSE for SfM-MVS estimates of linear tree metrics ranged between 2.6% and 20.7%, and between 12.3% and 47.5% for volumetric tree metrics. Tree stems were reconstructed very well though slender stems and branches were reconstructed poorly.
The second component of research tested the ability of SfM-MVS to reconstruct spatially-accurate 3D models from which height and DBH could be estimated. Each of the 35 landscape trees, which varied in height and species, were photographed, and ground truth values were obtained to evaluate against SfM-MVS estimates. As well as this, each photoset was thinned to find the minimum number of images required to achieve total image alignment in PhotoScan and produce an SfM point cloud (minimum photoset), from which 2D metrics could be estimated. The height and DBH were estimated by SfM-MVS from the complete photosets with RMSE of 6.2% and 5.6% respectively. The height and DBH were estimated from the minimum photosets with RMSE of 9.3% and 7.4% respectively. The minimum number of images required to achieve total alignment was between 20 and 50. There does not appear to be a correlation between the minimum number of images required for alignment and the error in the estimates of height or DBH (R2 =0.001 and 0.09 respectively). Tree height does not appear to affect the minimum number of images required for image alignment (R 2 =0.08).
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Strošiūnų šilo miško išteklių dinamika (1871-2002 metais) / Forest resources dynamics in Strošiūnai forest (1871-2002 years)Kaubrienė, Kristina 09 June 2006 (has links)
Subject of research: : Kaišiadorys state forest enterprise, Žiežmariai district, central part of Strošiūnai forest.
Goals of the research: Using Strošiūnai forest 1904, 1947, 1977, 1987 and 2002 years forest inventory data describe forest settlement, forest inventory works, changes in forest resources and possible reasons for that.
Methodology: comparative analysis using data grouping, comparing data, indicators specialization, average values and percentages calculation and generalization methods.
Research results: Strošiūnai forest, like separate economic unit was created in 1871 during forest inventory works carried out at Bačkonys (55,5 ha), Žasliai (225,4 ha) forests and Strošiūnai forest (804,2 ha), total 1085,2 ha.In years 1871-1904 total area increased by 37,9 ha, woodlands - 46,4 ha (0,8%), areas covered by forests 62,1 ha (2,5%), decreased areas without forest 15,6 ha (1,7%), agriculutural land 0,4 ha and land not used 8,2 ha (0,8%). Total forest area in years 1947-2002 decreased by 25,6 ha, forestland 2,7 ha, woodlands increased by 24%. Not a forestland area decreased by - 22,9ha (1,7%). Area of land dedicated for technological use increased by 21ha (1,6%), agricultural land decreased by 13 ha (1%). In years 1871-1904 pinewoods decreased from 92,7% to 89,8%, birch woodlands stayed the same, spruce forestland increased - from 3,4% to 7,7%. In years 1947-2002 pinewoods decreased almost a half from 82,1% to 46,0%. Areas with spruce increased almost three times (2... [to full text]
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Predicting time-since-fire from forest inventory data in Saskatchewan, CanadaSchulz, Rueben J. 05 1900 (has links)
Time-since-fire data are used to describe wildfire disturbances, the major disturbance type in the Boreal forest, over a landscape. These data can be used to calculate various parameters about wildfire disturbances, such as size, shape and severity. Collecting time-since-fire data is expensive and time consuming; the ability to derive it from existing forest inventory data would result in availability of fire data over larger areas. The objective of this thesis was to explore the use of forest inventory information for the prediction of time-since-fire data in the mixedwood boreal forests of Saskatchewan.
Regression models were used to predict time-since-fire from forest inventory variables for each inventory polygon with a stand age. Non-water polygons with no stand age value were assigned values from neighbouring polygons, after splitting long polygons that potentially crossed many historic fire boundaries. This procedure filled gaps that prevented polygons from being grouped together in latter analysis. The predicted time-since-fire ages were used to generate wildfire parameters such as age-class distributions and fire cycle. Three methods were examined to group forest inventory polygons together to predict fire event polygons: simple partitions, hierarchical clustering, and spatially constrained clustering. The predicted fire event polygons were used to generate polygon size distribution wildfire metrics.
I found that there was a relationship between time-since-fire and forest inventory variables at this study site, although the relationship was not strong. As expected, the strongest relationship was between the age of trees in a stand as indicated by the inventory and the time-since-fire. This relationship was moderately improved by including tree species composition, harvest modification value, and the ages of the surrounding polygons. Assigning no-age polygons neighbouring values and grouping the forest inventory polygons improved the predicted time-since-fire results when compared spatially to the observed time-since-fire data. However, a satisfactory method of comparing polygon shapes was not found, and the map outputs were highly dependent on the grouping method and parameters used. Overall it was found that forest inventory data did not have sufficient detail and accuracy to be used to derive high quality time-since-fire information.
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Theoretical and practical improvement of forest inventory by using laser scanning / Miškų inventorizacijos teorinis ir praktinis tobulinimas, naudojant lazerinį skenavimąBikuvienė, Ina 12 October 2012 (has links)
The aim and objectives. Overall: To improve forest inventory methods
using laser scanning.
Specific: To create methodological background for laser scanning in the
Lithuanian forest inventory and to provide practical suggestions for the use of
remote sensing technique in practice.
To attain the objective, the following tasks were formulated:
1. To investigate the influence of forest cover on the digital surface
model accuracy when it is drawn up based on laser scanning data;
2. To investigate estimation peculiarities of individual tree characteristics
using laser scanning data in the Lithuanian forest conditions;
3. To investigate estimation peculiarities of stand characteristics using
laser scanning data in the Lithuanian forest conditions;
4. Provide practical suggestions for the use of laser scanning technology
in the Lithuanian forest inventory.
Novelty and originality. In Lithuania it is the first research work of a
similar nature in forestry, thus from this viewpoint all topics are new and
significant.
The results obtained studying the issues of surface digital models based on
laser scanning data in forest-covered areas are actual to professionals and
practitioners also in other fields of science in Lithuania.
Other aspects of the work allowing to consider its originality on the
international level:
• The use of standwise forest inventory data along with laser scanning
data both in the estimation of tree dendrometric characteristics and determination of forest... [to full text] / Tikslas ir uždaviniai. Tiriamajam darbui buvo iškeltas tikslas:
Bendrasis: Tobulinti miškų inventorizacijos metodus naudojant lazerinį
skenavimą
Konkretusis: Sukurti lazerinio skenavimo naudojimo vykdant Lietuvos
miškų inventorizaciją metodinius pagrindus bei pateikti praktinius pasiūlymus
šiai nuotolinių tyrimų technologijai naudoti praktikoje.
Tyrimo tikslui pasiekti išsikelti šie uždaviniai:
1. Ištirti miško įtaką skaitmeninio žemės paviršiaus modelio tikslumui,
kai šis sudaromas lazerinio skenavimo duomenų pagrindu;
2. Ištirti atskiro medžio charakteristikų nustatymo ypatumus naudojant
lazerinio skenavimo duomenis Lietuvos miškų sąlygomis;
3. Ištirti medyno charakteristikų nustatymo ypatumus naudojant lazerinio
skenavimo duomenis Lietuvos miškų sąlygomis;
4. Pateikti praktinius pasiūlymus lazerinio skenavimo technologijai naudoti
Lietuvos miškų inventorizacijoje.
Naujumas ir originalumas. Šio darbo mokslinį ir praktinį naujumą reikia
nagrinėti keliais aspektais. Pirmiausia, Lietuvos mastu tai yra pirmas miškotyros
mokslinis darbas, nagrinėjantis lazerinio skenavimo taikymą miško
inventorizacijoje, todėl visos temos yra naujos ir reikšmingos. Rezultatai, gauti
tiriant skaitmeninių Žemės paviršiaus modelių sudarymo lazerinio skenavimo
duomenų pagrindu klausimus mišku padengtose teritorijose yra aktualūs ir kitų
Lietuvos mokslo sričių specialistams bei praktikams. Vertinant darbo naujumą
viso pasaulio kontekste – dauguma naudotų sprendimų yra adaptuoti Lietuvos
sąlygomis... [toliau žr. visą tekstą]
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Forest inventory improvement based on satellite images / Miškų inventorizacijos tobulinimas kosminių vaizdų pagrinduJonikavičius, Donatas 12 October 2012 (has links)
The aim of the study – improvement of on-going in Lithuania forest inventories based on satellite images and GIS databases.
Specific objective of the study – to explore the possibilities of methods applied for the collection of information from satellite images and GIS databases and its processing in order to determine various Lithuanian forest characteristics, focusing on a variety of forest inventory schemes.
4
The goals of the study:
1. To discuss methodological assumptions for the use of satellite images and GIS database information to estimate various characteristics of the Lithuanian forests.
2. To investigate methodological assumptions for the application of two-phase sampling scheme based on medium-resolution satellite images for the estimation of Lithuanian forest characteristics.
3. To investigate the possibilities of application of medium-resolution satellite images on the basis of two-phase sampling scheme in stand-wise, mature stands and pre-harvesting forest inventories.
4. To investigate methodological decisions and application peculiarities of fast detection of changes in the forest using medium-resolution satellite images under Lithuanian conditions.
Scientific novelty
The development of methodological background for the use of medium-resolution satellite images and two-phase sampling-based schemes in Lithuanian forest inventory.
The use of stand-wise forest inventory data as an auxiliary information together with medium-resolution satellite images in... [to full text] / Bendrasis darbo tikslas – Lietuvoje vykdomų miškų inventorizacijų tobulinimas kosminių nuotolinių tyrimų vaizdų bei GIS duomenų bazių pagrindu.
Darbo konkretusis tikslas – ištirti kosminių nuotolinių tyrimų vaizdų ir GIS duomenų bazių informacijos, jos apdorojimo metodų galimybes nustatant įvairias Lietuvos miškų charakteristikas, orientuojantis į įvairias miško inventorizacijos schemas.
Darbo uždaviniai:
1. Aptarti kosminių nuotolinių tyrimų vaizdų ir GIS duomenų bazių informacijos naudojimo vertinant įvairias Lietuvos miškų charakteristikas metodines prielaidas.
2. Ištirti dviejų fazių atrankos schemos taikymo vidutinės skiriamosios gebos kosminių vaizdų pagrindu vertinant įvairias Lietuvos miškų charakteristikas metodines prielaidas.
3. Ištirti dviejų fazių atrankos schema grindžiamo vidutinės skiriamosios gebos kosminių vaizdų taikymo sklypinėje, brandžių medynų bei prieškirtiminėje miškų inventorizacijose galimybes.
4. Ištirti operatyvaus pakitimų aptikimo miške, naudojant vidutinės skiriamosios gebos kosminius vaizdus, metodinius sprendimus bei jų taikymo Lietuvos sąlygomis ypatumus.
Mokslinis naujumas
Išvystyti vidutines skiriamosios gebos kosminių vaizdų ir dviejų fazių atranka grindžiamų vertinimo schemų naudojimo Lietuvos miškų inventorizacijoje metodiniai pagrindai.
Sklypinės miškų inventorizacijos duomenų naudojimas kaip pagalbinė informacija kartu su vidutinės skiriamosios gebos kosminiais vaizdais dviejų fazių atrankos schemose vertinant miško charakteristikas... [toliau žr. visą tekstą]
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