Search results for "puusto"
showing 8 items of 8 documents
Hierarchical log Gaussian Cox process for regeneration in uneven-aged forests
2021
We propose a hierarchical log Gaussian Cox process (LGCP) for point patterns, where a set of points x affects another set of points y but not vice versa. We use the model to investigate the effect of large trees to the locations of seedlings. In the model, every point in x has a parametric influence kernel or signal, which together form an influence field. Conditionally on the parameters, the influence field acts as a spatial covariate in the intensity of the model, and the intensity itself is a non-linear function of the parameters. Points outside the observation window may affect the influence field inside the window. We propose an edge correction to account for this missing data. The par…
Assessment of Classifiers and Remote Sensing Features of Hyperspectral Imagery and Stereo-Photogrammetric Point Clouds for Recognition of Tree Specie…
2018
Recognition of tree species and geospatial information on tree species composition is essential for forest management. In this study, tree species recognition was examined using hyperspectral imagery from visible to near-infrared (VNIR) and short-wave infrared (SWIR) camera sensors in combination with a 3D photogrammetric canopy surface model based on RGB camera stereo-imagery. An arboretum with a diverse selection of 26 tree species from 14 genera was used as a test area. Aerial hyperspectral imagery and high spatial resolution photogrammetric color imagery were acquired from the test area using unmanned aerial vehicle (UAV) borne sensors. Hyperspectral imagery was processed to calibrated …
Ojituksen ja ennallistamisen aiheuttamat muutokset kasvilajistossa ja –yhteisöissä
2013
Verkostonäkökulma ennallistamiskohteiden valinnassa
2013
Verkostonäkökulma korostuu vahvasti luonnonsuojelun suunnittelussa Suomessa ja maailmalla. Suojelualueita ei voi nähdä yksittäisinä eristyneinä alueina, vaan luonnonsuojelualueiden verkosto ja koko ympäröivä maisema ylläpitävät yhdessä tietyn alueen eliölajistoa. Parhaiden alueiden kytkeytyvyyden varmistamista ja verkostojen ylläpitämistä on myös ehdotettu ratkaisuksi biodiversiteetin säilyttämiselle, kun ilmastonmuutos pakottaa lajeja siirtymään uusille asuinalueille. Verkostonäkökulma kannattaa huomioida myös ennallistamiskohteiden valinnassa – mikä ei kuitenkaan ole yksiselitteistä ja helppoa. nonPeerReviewed
Ekosysteemin ennallistamisen ja luonnonhoidon ekologia
2013
Estimation of forest stand characteristics using individual tree detection, stochastic geometry and a sequential spatial point process model
2022
Airborne Laser Scanning (ALS) results in point-wise measurements of canopy height, which can further be used for Individual Tree Detection (ITD). However, ITD cannot find all trees because small trees can hide below larger tree crowns. Here we discuss methods where the plot totals and means of tree-level characteristics are estimated in such context. The starting point is a previously presented Horvitz–Thompson-like (HT-like) estimator, where the detectability is based on the larger tree crowns and a tuning parameter that models the detection condition. We propose a new method which is based on modeling the spatial pattern of hidden tree locations using a sequential spatial point process mo…
Plant biodiversity in boreal wood-pastures : impacts of grazing and abandonment
2016
Fotogrammetrisen 3D-latvusmallin ja hyperspektriaineiston käyttö aluetason puustotulkinnassa
2017
Seloste artikkelista Tuominen S., Balazs A., Honkavaara E., Polonen I., Saari H., Hakala T., Viljanen N. (2017). Hyperspectral UAV-imagery and photogrammetric canopy height model in estimating forest stand variables. Silva Fennica vol. 51 no. 5 article id 7721. https://doi. org/10.14214/sf.7721