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<p>I studien jämfördes bonitering med ståndortsegenskaper och övre höjd i en yngre tallskog i Mellansverige. I jämförelse mellan olika provytor på likvärdig mark och efter olika skötselåtgärder gav de två boniteringsmetoderna samma bonitet, trots variation i antal typarter och olika resultat vad gäller markvegetationstyp. Resultaten kan möjligen vara lokalt representativa men behöver ett större material för att kunna generaliseras på kommunnivå eller större.</p>

I studien jämfördes bonitering med ståndortsegenskaper och övre höjd i en yngre tallskog i Mellansverige. I jämförelse mellan olika provytor på likvärdig mark och efter olika skötselåtgärder gav de två boniteringsmetoderna samma bonitet, trots variation i antal typarter och olika resultat vad gäller markvegetationstyp. Resultaten kan möjligen vara lokalt representativa men behöver ett större material för att kunna generaliseras på kommunnivå eller större.

Submitted by M?rden L?les (marden.inacio@ufvjm.edu.br) on 2016-07-12T23:59:50Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) paula_ventura_silva.pdf: 2872431 bytes, checksum: 13667045a80e3b80429055fd7e4a5e15 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2016-07-18T14:50:22Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) paula_ventura_silva.pdf: 2872431 bytes, checksum: 13667045a80e3b80429055fd7e4a5e15 (MD5) / Made available in DSpace on 2016-07-18T14:50:22Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) paula_ventura_silva.pdf: 2872431 bytes, checksum: 13667045a80e3b80429055fd7e4a5e15 (MD5) Previous issue date: 2015 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / RESUMO SILVA, Paula Ventura da, M.Sc., Emprego de redes neurais artificiais com Skip-Layer Connections na mensura??o florestal. 2015. 46 f. Disserta??o (Mestrado em Ci?ncia Florestal) ? Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina, 2015. O objetivo principal deste estudo foi avaliar a aplica??o de Redes Neurais Artificiais (RNA) utilizando a t?cnica Skip-layer connections, com e sem recorr?ncia, para estima??o do volume individual e da altura total de ?rvores de eucalipto. Os objetivos espec?ficos foram testar e avaliar as redu??es no tamanho da base de dados do conjunto de ajuste (treinamento) para estima??o dessas vari?veis. Os dados utilizados foram provenientes de ?rvores abatidas para cubagem (estima??o do volume individual) e de medi??es de parcelas permanentes de invent?rios florestais cont?nuos (estima??o da altura total), em ?rea de povoamentos de eucalipto localizados no sul da Bahia, Brasil. Foram treinadas redes do tipo Multilayer Perceptron (MLP), utilizando a fun??o de ativa??o log?stica nas camadas intermedi?ria e de sa?da e oito neur?nios na camada oculta. O n?mero de neur?nios na camada de entrada variou conforme o n?mero e o tipo de vari?vel (qualitativa ou quantitativa) em cada estudo. Os crit?rios de parada foram o erro m?dio quadr?tico de 0,0001 ou 3.000 ciclos (?pocas). Em seguida, as RNA selecionadas foram aplicadas em parte dos dados separados, para generaliza??o (valida??o). O software utilizado para o treinamento e a generaliza??o das RNA foi o NeuroForest 3.3. Para compara??o dos resultados obtidos pelas RNA, foram ajustados os modelos tradicionais de regress?o tanto para volume, quanto para altura, e tamb?m foram treinadas e aplicadas RNA usando o algoritmo Resilient Propagation, comumente utilizado em aplica??es da mensura??o florestal. A avalia??o dos resultados gerados pelas RNA e pelos modelos de regress?o foi feita por meio do coeficiente de correla??o entre os valores observados e estimados, de gr?ficos de dispers?o e de histogramas de frequ?ncia percentual dos erros percentuais. As Redes Neurais Artificiais utilizando Skip-layer connections apresentaram resultados satisfat?rios para estima??o de volume e de altura de ?rvores de eucalipto, o que evidencia a possibilidade de aplicar a t?cnica em mensura??o e manejo florestal e uma expressiva redu??o das bases de dados para treinamento das RNA. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Ci?ncia Florestal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2015. / ABSTRACT SILVA, Paula Ventura da, M.Sc. Artificial neural networks with skip-layer connections in forest measurement. 2015. 46 f. Dissertation (Master in Forest Science) ? Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina, 2015. The aim of this study was to evaluate the application of Artificial Neural Networks (ANN) using the Skip-layer connections technique, with and without recurrence, to estimate the individual volume and total eucalyptus trees height. Its specific objectives were to test and evaluate reduction in the size of the adjustment assembly database (training) for estimating these variables. The data came from trees felled for scaling (estimation of individual volume) and measurements of permanent plots of continuous forest inventories (estimation of the total height), in eucalypt plantation area located in the south of Bahia, Brazil. Multilayer Perceptron (MLP) network type, using the logistic activation function in the intermediate and output layers and eight neurons in the hidden layer, were trained. The neurons number in the input layer varied according to the number and type of the variable (qualitative or quantitative) in each study. The stopping criteria were the root mean square error 0.0001 or 3,000 cycles (seasons). The software used for the RNA training and generalization was the NeuroForest 3.3. To compare the results obtained by RNA, traditional regression models were set for both the volume and the height, as well as RNA were trained and applied using the Resilient Propagation algorithm, commonly used in forest measurement applications. The evaluation of the results generated by the RNA and by the regression models was made via the correlation coefficient between observed and estimated values, scatter plots and histograms percentage frequency of the percentage errors. Artificial Neural Networks using Skip-layer connections showed satisfactory results for the estimation of volume and eucalyptus trees height, demonstrating the possibility of applying the technique in measuring and forest management and a significant reduction of databases for RNA training.

The overall objectives of this dissertation were to (1) determine whether leaf area index (LAI) (Chapter 2), as well as stem density and height to live crown (Chapter 3) can be estimated accurately in intensively managed pine plantations using small-footprint, multiple-return airborne laser scanner (lidar) data, and (2) ascertain whether leaf area index in temperate mixed forests is best estimated using multiple-return airborne laser scanning (lidar) data or dual-band, single-pass interferometric synthetic aperture radar data (from GeoSAR) alone or both in combination (Chapter 4). In situ measurements of LAI, mean height, height to live crown, and stem density were made on 109 (LAI) or 110 plots (all other variables) under a variety of stand conditions. Lidar distributional metrics were calculated for each plot as a whole as well as for crown density slices (newly introduced in this dissertation). These metrics were used as independent variables in best subsets regressions with LAI, number of trees, mean height to live crown, and mean height (measured in situ) as the dependent variables. The best resulting model for LAI in pine plantations had an R2 of 0.83 and a cross-validation (CV) RMSE of 0.5. The CV-RMSE for estimating number of trees on all 110 plots was 11.8 with an R2 of 0.92. Mean height to live crown was also well-predicted (R2 = 0.96, CV-RMSE = 0.8 m) with a one-variable model. In situ measurements of temperate mixed forest LAI were made on 61 plots (21 hardwood, 36 pine, 4 mixed pine hardwood). GeoSAR metrics were calculated from the X-band backscatter coefficients (four looks) as well as both X- and P-band interferometric heights and magnitudes. Both lidar and GeoSAR metrics were used as independent variables in best subsets regressions with LAI (measured in situ) as the dependent variable. Lidar metrics alone explained 69% of the variability in temperate mixed forest LAI, while GeoSAR metrics alone explained 52%. However, combining the LAI and GeoSAR metrics increased the R2 to 0.77 with a CV-RMSE of 0.42. Analysis of data from active sensors shows strong potential for eventual operational estimation of biophysical parameters essential to silviculture. / Ph. D.

Syftet med arbetet var att utvärdera mobilapplikationen KATAM avseende noggrannhet, tidsåtgång, precision och praktisk användning i jämförelse med volymuppskattning med dataklave och skördarrapport. Resultatet vid diameterjämförelsen visar på snarlika uppskattningar från KATAM respektive dataklaven. KATAM hade högre medelgrundyta, 7 % och grövre medeldiameter, 3,7 %, i jämförelse med dataklaven. KATAM hade även överskattningar av medelstammen volym i jämförelse med skördarrapporten och dataklaven, från 2,5 % till 17,6 % beroende på vilket urval av provytor och vilken programversion av KATAM som användes. Underlaget från volymuppskattningar var litet och hade felkällor vilket gjorde resultaten från mätningarna osäkra. Trots att studien visade på en överskattning av diametern talar den inbördes precisionen för att KATAM skulle kunna bli ett alternativ till Dataklaven vid uppskattning av medeldiametern. / The purpose of this essay was to evaluate the mobile application KATAM of accuracy, time, precision and practical use in comparison to volume estimation with data Digital Caliper and harvester report. The result of the diameter comparison showed similar estimates from KATAM and the Digital Caliper respectively. KATAM had a higher mean basel area, 7% and coarser mean diameter, 3.7%, compared to the Digital Caliper. KATAM also had overestimations in volume as compared to the harvesting report and the Digital Caliper concerning the mean stem, from 2.5% to 17.6%, depending on which sample areas were included and which version of KATAM was used. However, the basis of volume estimates was small and had error sources, which made the results of the measurements uncertain. Although the study shows an overestimation of the diameter, the mutual precision indicates that KATAM could be an alternative to the Digital Caliper when estimating the mean diameter.

Diss. (sammanfattning) Umeå : Sveriges lantbruksuniv. / Härtill 5 uppsatser.

Intresset för olika hyggesfria skogsbruksmetoder ökar men frågan är hur en skogsbruksplan kan anpassas till detta och vilken metod som kan användas. Denna studie inriktade sig på att mäta i fullskiktade skogar med enkla verktyg för att få ut beståndsdata till nytta för skötseln och att användas till en skogsbruksplan. För att få fram diameterspridningen klavades träden. Det krävdes minst 600 m2 för att få tillräcklig kvalitet i diameterspridning. För volymen jämfördes klavning, relaskopmätning och laserdata. Resultatet visade att det är svårt att mäta volym i fullskiktade bestånd beroende på tätheten och ojämnheten. Inte minst gäller detta relaskopmätning som undervärderade volymen. Klavning och laserdata fick ungefär samma precision. Studien visade också att tidsåtgången i fält för klavning jämfört med vanlig planläggning med relaskop endast skiljde några få minuter. Om klavning kombineras med att hämta volymen från laserdata kan till och med denna metod vara mer tidseffektiv.