108 research outputs found
Structural Changes in Boreal Forests Can Be Quantified Using Terrestrial Laser Scanning
Terrestrial laser scanning (TLS) has been adopted as a feasible technique to digitize trees and forest stands, providing accurate information on tree and forest structural attributes. However, there is limited understanding on how a variety of forest structural changes can be quantified using TLS in boreal forest conditions. In this study, we assessed the accuracy and feasibility of TLS in quantifying changes in the structure of boreal forests. We collected TLS data and field reference from 37 sample plots in 2014 (T1) and 2019 (T2). Tree stems typically have planar, vertical, and cylindrical characteristics in a point cloud, and thus we applied surface normal filtering, point cloud clustering, and RANSAC-cylinder filtering to identify these geometries and to characterize trees and forest stands at both time points. The results strengthened the existing knowledge that TLS has the capacity to characterize trees and forest stands in space and showed that TLS could characterize structural changes in time in boreal forest conditions. Root-mean-square-errors (RMSEs) in the estimates for changes in the tree attributes were 0.99â1.22 cm for diameter at breast height (Îdbh), 44.14â55.49 cm2 for basal area (Îg), and 1.91â4.85 m for tree height (Îh). In general, tree attributes were estimated more accurately for Scots pine trees, followed by Norway spruce and broadleaved trees. At the forest stand level, an RMSE of 0.60â1.13 cm was recorded for changes in basal area-weighted mean diameter (ÎDg), 0.81â2.26 m for changes in basal area-weighted mean height (ÎHg), 1.40â2.34 m2/ha for changes in mean basal area (ÎG), and 74â193 n/ha for changes in the number of trees per hectare (ÎTPH). The plot-level accuracy was higher in Scots pine-dominated sample plots than in Norway spruce-dominated and mixed-species sample plots. TLS-derived tree and forest structural attributes at time points T1 and T2 differed significantly from each other (p < 0.05). If there was an increase or decrease in dbh, g, h, height of the crown base, crown ratio, Dg, Hg, or G recorded in the field, a similar outcome was achieved by using TLS. Our results provided new information on the feasibility of TLS for the purposes of forest ecosystem growth monitoring
Structural Changes in Boreal Forests Can Be Quantified Using Terrestrial Laser Scanning
Terrestrial laser scanning (TLS) has been adopted as a feasible technique to digitize trees and forest stands, providing accurate information on tree and forest structural attributes. However, there is limited understanding on how a variety of forest structural changes can be quantified using TLS in boreal forest conditions. In this study, we assessed the accuracy and feasibility of TLS in quantifying changes in the structure of boreal forests. We collected TLS data and field reference from 37 sample plots in 2014 (T1) and 2019 (T2). Tree stems typically have planar, vertical, and cylindrical characteristics in a point cloud, and thus we applied surface normal filtering, point cloud clustering, and RANSAC-cylinder filtering to identify these geometries and to characterize trees and forest stands at both time points. The results strengthened the existing knowledge that TLS has the capacity to characterize trees and forest stands in space and showed that TLS could characterize structural changes in time in boreal forest conditions. Root-mean-square-errors (RMSEs) in the estimates for changes in the tree attributes were 0.99â1.22 cm for diameter at breast height (Îdbh), 44.14â55.49 cm2 for basal area (Îg), and 1.91â4.85 m for tree height (Îh). In general, tree attributes were estimated more accurately for Scots pine trees, followed by Norway spruce and broadleaved trees. At the forest stand level, an RMSE of 0.60â1.13 cm was recorded for changes in basal area-weighted mean diameter (ÎDg), 0.81â2.26 m for changes in basal area-weighted mean height (ÎHg), 1.40â2.34 m2/ha for changes in mean basal area (ÎG), and 74â193 n/ha for changes in the number of trees per hectare (ÎTPH). The plot-level accuracy was higher in Scots pine-dominated sample plots than in Norway spruce-dominated and mixed-species sample plots. TLS-derived tree and forest structural attributes at time points T1 and T2 differed significantly from each other (p < 0.05). If there was an increase or decrease in dbh, g, h, height of the crown base, crown ratio, Dg, Hg, or G recorded in the field, a similar outcome was achieved by using TLS. Our results provided new information on the feasibility of TLS for the purposes of forest ecosystem growth monitoring
Terrestrial Laser Scanning Reveal Connection Between Changes in Tree Stem Dimensions and Crown Structure
Peer reviewe
Understanding 3D structural complexity of individual Scots pine trees with different management history
Tree functional traits together with processes such as forest regeneration, growth, and mortality affect forest and tree structure. Forest management inherently impacts these processes. Moreover, forest structure, biodiversity, resilience, and carbon uptake can be sustained and enhanced with forest management activities. To assess structural complexity of individual trees, comprehensive and quantitative measures are needed, and they are often lacking for current forest management practices. Here, we utilized 3D information from individual Scots pine (Pinus sylvestris L.) trees obtained with terrestrial laser scanning to, first, assess effects of forest management on structural complexity of individual trees and, second, understand relationship between several tree attributes and structural complexity. We studied structural complexity of individual trees represented by a single scale-independent metric called "box dimension." This study aimed at identifying drivers affecting structural complexity of individual Scots pine trees in boreal forest conditions. The results showed that thinning increased structural complexity of individual Scots pine trees. Furthermore, we found a relationship between structural complexity and stem and crown size and shape as well as tree growth. Thus, it can be concluded that forest management affected structural complexity of individual Scots pine trees in managed boreal forests, and stem, crown, and growth attributes were identified as drivers of it.Peer reviewe
Close-range hyperspectral spectroscopy reveals leaf water content dynamics
Water plays a crucial role in maintaining plant functionality and drives many ecophysiological processes. The distribution of water resources is in a continuous change due to global warming affecting the productivity of ecosystems around the globe, but there is a lack of non-destructive methods capable of continuous monitoring of plant and leaf water content that would help us in understanding the consequences of the redistribution of water. We studied the utilization of novel small hyperspectral sensors in the 1350-1650 nm and 2000-2450 nm spectral ranges in non-destructive estimation of leaf water content in laboratory and field conditions. We found that the sensors captured up to 96% of the variation in equivalent water thickness (EWT, g/m(2)) and up to 90% of the variation in relative water content (RWC). Further tests were done with an indoor plant (Dracaena marginate Lem.) by continuously measuring leaf spectra while drought conditions developed, which revealed detailed diurnal dynamics of leaf water content. The laboratory findings were supported by field measurements, where repeated leaf spectra measurements were in fair agreement (R-2 = 0.70) with RWC and showed similar diurnal dynamics. The estimation of leaf mass per area (LMA) using leaf spectra was investigated as a pathway to improved RWC estimation, but no significant improvement was found. We conclude that close-range hyper spectral spectroscopy can provide a novel tool for continuous measurement of leaf water content at the single leaf level and help us to better understand plant responses to varying environmental conditions.Peer reviewe
Effects of Stem Density on Crown Architecture of Scots Pine Trees
Trees adapt to their growing conditions by regulating the sizes of their parts and their relationships. For example, removal or death of adjacent trees increases the growing space and the amount of light received by the remaining trees enabling their crowns to expand. Knowledge about the effects of silvicultural practices on crown size and shape and also about the quality of branches affecting the shape of a crown is, however, still limited. Thus, the aim was to study the crown structure of individual Scots pine trees in forest stands with varying stem densities due to past forest management practices. Furthermore, we wanted to understand how crown and stem attributes and also tree growth affect stem area at the height of maximum crown diameter (SAHMC), which could be used as a proxy for tree growth potential. We used terrestrial laser scanning (TLS) to generate attributes characterizing crown size and shape. The results showed that increasing stem density decreased Scots pine crown size. TLS provided more detailed attributes for crown characterization compared with traditional field measurements. Furthermore, decreasing stem density increased SAHMC, and strong relationships (Spearman's correlations > 0.5) were found between SAHMC and crown and stem size and also stem growth. Thus, this study provided quantitative and more comprehensive characterization of Scots pine crowns and their growth potential. The combination of a traditional growth and yield study design and 3D characterization of crown architecture and growth potential can open up new research possibilities.Peer reviewe
Emissions and environmental levels of pharmaceuticals : Upscaling to the Baltic Sea Region
The report describes the Baltic Pharma Load model (BPL) and the estimated environmental loads and concentrations of selected active pharmaceutical ingredients (APIs). The BPL model was developed as a part of the project Clear Waters from Pharmaceuticals (CWPharma) funded by the EUâs Interreg Baltic Sea Region Programme.
The calculation model uses national sales statistics as the driving parameter and takes into account selected differences in country-specific practices in e.g. waste management and sewer network coverage. The GIS-based model was compiled as a series of command scripts using the computing language and environment R (R Core Team 2020) and a calculation grid covering the entire Baltic Sea drainage basin. The calculation grid divides the Baltic Sea Region (BSR) into one square kilometer grid cells, with each grid cell containing the background information required for the calculations.
The BPL model and the calculation grid are available in the .zip-file as a series of R scripts and .rds-files
Sedimenttien pilaantuneisuuden ja puhdistamistarpeen arviointi ja sÀÀntely â KansainvĂ€lisiĂ€ kĂ€ytĂ€ntöjĂ€
Sedimenttien pilaantuneisuutta arvioidaan eri valtioissa monin eri tavoin ja eri nÀkökulmista, mutta monessa tapauksessa arvioiden pohjana ovat sedimentille laaditut haitta-ainekohtaiset ohje-, kynnys- tai raja-arvot tai ympÀristönlaatunormit. EnsimmÀiset sedimenttiÀ koskevat ohjearvot laadittiin 1980-luvulla ja tÀmÀn jÀlkeen on laadittu monia joko maailmanlaajuisesti kÀytössÀ olevia ohjearvoja tai kansallisia ohjearvoja. NÀiden arvojen merkitys vaihtelee maakohtaisesti ja niitÀ voidaan kÀyttÀÀ kriteereinÀ pilaantuneisuutta arvioitaessa, kunnostustoimista pÀÀtettÀessÀ tai ne voivat toimia laukaisijana lisÀtutkimuksille kokonaisvaltaisemmassa riskinarvioinnissa. Myös EU:n prioriteettiainedirektiivi antaa jÀsenvaltioille mahdollisuuden muodostaa sedimentin ja/tai eliöstön ympÀristönlaatunormeja kansallisella tasolla ja soveltaa nÀitÀ ympÀristönlaatunormeja Euroopan yhteisön tasolla vedelle asetettujen ympÀristönlaatunormien sijasta. Muilla Pohjoismailla, kuten Norjalla ja Ruotsilla, on raja-arvoja pilaantuneelle sedimentille.
Suomessa ei ole toistaiseksi ohjeistusta tai raja-arvoja sedimenttien pilaantuneisuuden, ympÀristö- ja terveysriskien ja kunnostustarpeen arviointiin. Myös pilaantuneisiin sedimentteihin liittyvÀ sÀÀntely mm. selvitys- ja puhdistusvelvoitteiden ja vastuiden osalta on puutteellista. Suomen sisÀvesillÀ on kuitenkin alueita, joiden sedimenttien haitta-ainepitoisuudet ovat huomattavasti luonnontilaista korkeammalla tasolla, sijaiten pÀÀasiassa joko entisten tai nykyisten teollisuuslaitosten lÀhellÀ. LisÀksi merialueilla on jokien suistojen, laivareittien ja satamien lÀhellÀ laajoja alueita, joiden sedimenteissÀ on suurina pitoisuuksia haitta-aineita. NÀistÀ voi aiheutua suoranaista haittaa vesieliöille sellaisenaan tai esimerkiksi ruoppausten yhteydessÀ ja vÀlillistÀ haittaa ihmisterveydelle muun muassa kalansyönnin kautta. Suomessa sedimenttien haitta-ainekartoituksia tehdÀÀn lÀhinnÀ luvanvaraisten ruoppaushankkeiden yhteydessÀ. Ruoppaus- ja lÀjitysohje mÀÀrittelee sedimenttien lÀjityskelpoisuuden, muttei ota kantaa niiden pilaantuneisuuteen ja kunnostustarpeeseen.
Pilaantuneiksi todettujen sedimenttien kunnostus voi tapahtua esimerkiksi (i) poistamalla pilaantunut sedimentti ruoppaamalla, (ii) peittÀmÀllÀ, tai (iii) hyödyntÀmÀllÀ luontaista puhdistumista. Luontaisen puhdistumisen on osoitettu olevan merkityksellinen prosessi. YhtÀÀltÀ korkeitakin haitta-ainepitoisuuksia sisÀltÀvien sedimenttien paikalleen jÀttÀminen saattaa olla ympÀristö- ja terveysriskien kannalta perusteltua, mikÀli haitta-aineista ei aiheudu merkittÀvÀÀ eliö- tai ihmisaltistusta eivÀtkÀ ne kulkeudu/leviÀ ympÀristöön. Toisaalta korkeita haitta-aineita sisÀltÀvÀ sedimentti voi aiheuttaa jatkuvaa altistusta tai toimia jatkuvana haitta-aineiden pÀÀstölÀhteenÀ ympÀröivÀÀn veteen.
EdellÀ mainittujen seikkojen vuoksi sedimenttien pilaantuneisuuden, ympÀristö- ja terveysriskien sekÀ kunnostustarpeen arviointiin olisi vÀlttÀmÀtöntÀ luoda ohjeistusta myös Suomessa. Ohjeistuksella tÀhdÀttÀisiin yhtenÀisiin kÀytÀntöihin ja siihen, ettÀ mahdolliset kunnostustoimenpiteet suunnattaisiin tarkoituksenmukaisella tavalla vesiympÀristön tilaa merkittÀvÀsti heikentÀviin kohteisiin.
Assessment and regulation of sediment contamination and the need for remediation â International practices
In different countries, the contamination of sediments is assessed in number of ways and from various perspectives, but in many cases, these assessments are based on specific guidelines, threshold values, limit values or environmental quality standards for sediment. The first guideline values for sediment assessment were developed in the 1980s, and these have since been followed by a number of international and national guideline values. The significance of these values varies from country to country, and they can be used as criteria for assessing contamination, in connection with decision-making on remediation action or as a basis for further research in more comprehensive risk assessments. The EUâs directive on priority substances also allows member states to establish environmental quality standards (EQS) for sediment and/or biota at the national level and to apply these EQSs instead of EQSs for water at the European Community level. Other Nordic countries, such as Norway and Sweden, have threshold values for contaminated sediment.
Currently, there are no guidelines or threshold values in Finland for assessing the contamination of sediments, environmental and health risks or the need for remediation. The regulation regarding contaminated sediments as it relates to, for example, survey and purification obligations and responsibilities, is lacking. However, there are areas in Finland's inland waters where the levels of hazardous substances in sediments are significantly elevated in relation to the natural state, mainly in the vicinity of decommissioned or operational industrial facilities. In addition, there are vast sea areas with high concentrations of hazardous substances in their sediments that are located close to estuaries, shipping routes and ports. These substances can cause direct harm to aquatic organisms on their own or in connection with dredging, and indirect harm to human health, for example through the consumption of fish. In Finland, surveys on sediment contamination are carried out mainly in connection with dredging projects subject to a permit. The instructions on dredging and deposition of dredged material determine the suitability of the sediments for deposition but do not address their level of contamination or the need for remediation.
Contaminated sediments can be remediated, for example, by (i) removing the contaminated sediment by dredging, (ii) capping them or (iii) making use of natural recovery. Natural recovery has been shown to be a meaningful process. On the one hand, leaving sediments containing even high levels of hazardous substances as they are may be justified with regard to the environmental risks and health risks, provided that the hazardous substances do not give rise to significant exposure for organisms or humans and do not spread into the environment. On the other hand, sediments containing high levels of hazardous substances may lead to continuous exposure or act as a source of continuous emission of hazardous substances into the surrounding waters.
Due to the above-mentioned factors, it is necessary to create guidelines for assessing the contamination of sediments, environmental risks and health risks and the need for remediation, also in Finland. The guidelines would be aimed at establishing uniform practices and ensuring that possible remediation measures would be appropriately targeted at sites that significantly degrade the state of the aquatic environment
The effect of SME internationalization motivators on initial and successive international market entry mode choice
Source at https://vkm.no/In preparation for a legal implementation of EU-regulation 1829/2003, the Norwegian Environment Agency (former Norwegian Directorate for Nature Management) has requested the Norwegian Food Safety Authority (NFSA) to give final opinions on all genetically modified organisms (GMOs) and products containing or consisting of GMOs that are authorized in the European Union under Directive 2001/18/EC or Regulation 1829/2003/EC within the Authorityâs sectoral responsibility. The Norwegian Food Safety Authority has therefore, by letter dated 13 February 2013 (ref. 2012/150202), requested the Norwegian Scientific Committee for Food Safety (VKM) to carry out scientific risk assessments of 39 GMOs and products containing or consisting of GMOs that are authorized in the European Union. The request covers scope(s) relevant to the Gene Technology Act. The request does not cover GMOs that VKM already has conducted its final risk assessments on. However, the Agency requests VKM to consider whether updates or other changes to earlier submitted assessments are necessary.I forbindelse med forberedelse til implementering av EU-forordning 1829/2003 i norsk rett har MiljĂždirektoratet (tidligere Direktoratet for Naturforvalting) bedt Mattilsynet om vurderinger av allegenmodifiserte organismer (GMOer) og avledete produkter som inneholder eller bestĂ„r av GMOer som er godkjent under forordning 1829/2003 eller direktiv 2001/18 som er godkjent for ett eller flere bruksomrĂ„der som omfattes av genteknologiloven. PĂ„ den bakgrunnen har Mattilsynet, i brev av 13. februar 2013 (ref. 2012/150202), bedt Vitenskapskomiteen for mattrygghet (VKM) om Ă„ utarbeide endelige vitenskapelige risikovurderinger av 39 GMOer og avledete produkter som inneholder eller bestĂ„r av genmodifiserte organismer, innen Mattilsynets sektoransvar. VKM er bedt om endelige risikovurderinger for de EU-godkjente sĂžknader hvor VKM ikke har avgitt endelig risikovurdering. I tillegg er VKM bedt om Ă„ vurdere hvorvidt det er nĂždvendig med oppdatering eller annen endring av de endelige risikovurderingene som VKM tidligere har lever
PFASs in Finnish rivers and fish and the loading of PFASs to the Baltic Sea
The concentrations of per- and polyfluoroalkyl substances (PFASs) in the Finnish aquatic environment were measured in riverine waters and in inland, coastal and open sea fish. In addition, the PFAS load to the Baltic Sea from 11 rivers was calculated. Measurements show that PFASs, including restricted perfluorooctane sulfonic acid (PFOS), are widely present in the Finnish aquatic environment. At three out of 45 sampling sites, the concentration of PFOS in fish exceeded the environmental quality standard (EQS) of the Water Framework Directive (WFD). The annual average (AA) â23PFAS concentration in surface waters ranged from 1.8 to 42 ng Lâ1 and the concentration of PFOS exceeded the AA-EQS in three out of 13 water bodies. In European perch (Perca fluviatilis) and Baltic herring (Clupea harengus membras), the âPFAS concentration ranged from 0.98 to 1 ”g kgâ1 f.w. (fresh weight) and from 0.2 to 2.4 ”g kgâ1 f.w., respectively. The highest concentrations in both surface water and fish were found in waters of southern Finland. The riverine export of â10PFAS to the Baltic Sea from individual rivers ranged from 0.4 kg yrâ1 to 18 kg yrâ1. PFAS concentrations in fish of point-source-polluted sites and coastal sites were higher compared to fish of open sea or diffusely polluted sites. The PFAS profiles in surface waters of background sites were different from other sites. This study shows that PFASs are widely found in the Finnish aquatic environment. Different PFAS profiles in samples from background areas and densely populated areas indicate diverse sources of PFASs. Although atmospheric deposition has a substantial influence on PFAS occurrence in remote areas, it is not the dominant source of all PFASs to the aquatic environment of Finland. Rather, wastewaters and presumably contaminated land areas are major sources of PFASs to this aquatic environment
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