Silva Fennica最新文献_第6页

Predicting factual sawlog volumes in Scots pine dominated forests using airborne laser scanning data 利用机载激光扫描数据预测苏格兰松林的实际锯木量

IF 1.8 3区农林科学

Silva Fennica Pub Date : 2019-01-01 DOI: 10.14214/sf.10183

Tomi Karjalainen, P. Packalen, J. Räty, M. Maltamo

{"title":"Predicting factual sawlog volumes in Scots pine dominated forests using airborne laser scanning data","authors":"Tomi Karjalainen, P. Packalen, J. Räty, M. Maltamo","doi":"10.14214/sf.10183","DOIUrl":"https://doi.org/10.14214/sf.10183","url":null,"abstract":"The aim in the study was to compare alternatives for the prediction of factual sawlog volumes using airborne laser scanning (ALS) data in Scots pine ( L.) dominated forests in eastern Finland. Accurate estimates of factual sawlog volume are desirable to ease the planning of harvesting operations. The factual sawlog volume of pines was derived from visual bucking, i.e. a procedure where the defects were located on each stem during sample plot measurements. For other species, the theoretical sawlog volume was considered also as the factual sawlog volume due to data restrictions. We predicted factual sawlog volume with eight alternatives that were based on either linear mixed-effects models or k-nearest neighbour imputations. An existing sawlog reduction model, commonly used in Finland, was also tested individually and combined with a number of the alternatives, and site type information was also utilised. Model fitting and prediction was implemented at the 15 Ã 15 m level, but accuracy was assessed at the 30 Ã 30 m level. The relative root mean squared error (RMSE%) values for the factual sawlog volume predictions varied between 20.9% and 33.5%, and the best accuracy was obtained with a linear mixed-effects model. These results indicate that factual sawlog volumes in Scots pine dominated forests can be predicted with reasonable accuracy with ALS data.Pinus sylvestris","PeriodicalId":49520,"journal":{"name":"Silva Fennica","volume":"1 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66767374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Seasonal dynamics of lingonberry and blueberry spectra 越橘和蓝莓光谱的季节动态

IF 1.8 3区农林科学

Silva Fennica Pub Date : 2019-01-01 DOI: 10.14214/SF.10150

Petri R. Forsström, J. Peltoniemi, M. Rautiainen

{"title":"Seasonal dynamics of lingonberry and blueberry spectra","authors":"Petri R. Forsström, J. Peltoniemi, M. Rautiainen","doi":"10.14214/SF.10150","DOIUrl":"https://doi.org/10.14214/SF.10150","url":null,"abstract":"Accurate mapping of the spatial distribution of understory species from spectral images requires ground reference data which represent the prevailing phenological stage at the time of image acquisition. We measured the spectral bidirectional reflectance factors (BRFs, 350â2500 nm) at varying view angles for lingonberry ( L.) and blueberry ( L.) throughout the growing season of 2017 using Finnish Geospatial Research Instituteâs FIGIFIGO field goniometer. Additionally, we measured spectra of leaves and berries of both species, and flowers of lingonberry. Both lingonberry and blueberry showed seasonality in visible and near-infrared spectral regions which was linked to occurrences of leaf growth, flowering, berrying, and leaf senescence. The seasonality of spectra differed between species due to different phenologies (evergreen vs. deciduous). Vegetation indices, normalized difference vegetation index (NDVI), moisture stress index (MSI), plant senescence reflectance index (PSRI), and red-edge inflection point (REIP2), showed characteristic seasonal trends. NDVI and PSRI were sensitive to the presence of flowers and berries of lingonberry, while with blueberry the effects were less evident. Off-nadir observations supported differentiating the dwarf shrub species from each other but showed little improvement for detection of flowers and berries. Lingonberry and blueberry can be identified by their spectral signatures if ground reference data are available over the entire growing season. The spectral data measured in this study are reposited in the publicly open SPECCHIO Spectral Information System.Vaccinium vitis-idaeaVaccinium myrtillus","PeriodicalId":49520,"journal":{"name":"Silva Fennica","volume":"1 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66767578","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 13

Continuous picking may increase bilberry yields 连续采摘可以增加越橘的产量

IF 1.8 3区农林科学

Silva Fennica Pub Date : 2019-01-01 DOI: 10.14214/sf.10043

O. Manninen, R. Peltola

{"title":"Continuous picking may increase bilberry yields","authors":"O. Manninen, R. Peltola","doi":"10.14214/sf.10043","DOIUrl":"https://doi.org/10.14214/sf.10043","url":null,"abstract":"Accumulated knowledge about the health benefits of bilberry ( L.) has increased the demand and utilization of wild bilberries. Intensive berry picking by metal rakes is believed to cause damage in bilberry stands in areas under continuous picking pressure, and hence expected to hamper the production of berries in forthcoming years. We conducted an experiment to examine the effect of continuous bilberry picking by metal rake on the number of bilberry flowers and fruits, fruit mass, compensation for biomass loss after picking, and plant functional type abundance in the understorey in northern Finland. Bilberry lost less than 0.5% of its biomass annually during the three-year study period due to rake harvesting. The number of flowers was not significantly affected by damage caused by picking, while both fruit production and fruit set increased without any indication of reduced fruit mass, and biomass loss was fully compensated. Moreover, the relative abundance of plant functional types was not affected by picking during the study. We suggest that the low intensity and timing of damage act as a buffer against the adverse effects of picking on bilberry fruit production. On the basis of this study, it is reasonable to anticipate that there are no indications that current intensive berry picking would not be on a sustainable level.Vaccinium myrtillus","PeriodicalId":49520,"journal":{"name":"Silva Fennica","volume":"1 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66767112","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of prior tree marking, thinning method and topping diameter on harvester performance in a first thinning operation – a field experiment 在第一次间伐作业中，树木标记、间伐方法和顶径对收获机性能的影响——田间试验

IF 1.8 3区农林科学

Silva Fennica Pub Date : 2019-01-01 DOI: 10.14214/sf.10178

Franz Holzleitner, Magdalena Langmaier, E. Hochbichler, Bernhardt Obermayer, K. Stampfer, C. Kanzian

{"title":"Effect of prior tree marking, thinning method and topping diameter on harvester performance in a first thinning operation – a field experiment","authors":"Franz Holzleitner, Magdalena Langmaier, E. Hochbichler, Bernhardt Obermayer, K. Stampfer, C. Kanzian","doi":"10.14214/sf.10178","DOIUrl":"https://doi.org/10.14214/sf.10178","url":null,"abstract":"The effect of harvester operator tree selection or prior tree marking in thinning operations on satisfactory results and performance has been widely discussed. In harvester operator tree selection, the machine operator decides on the fly which trees are selected to remain or cut. The objective of the study was to analyze the effect of prior tree marking, thinning method and topping diameter on harvester performance in low-diameter thinning operations. The entire thinning operation was captured using video technology. Overall, 2.36 ha divided into 48 plots with 5202 trees were thinned with an average diameter at breast height (dbh) over bark for all plots of between 12.5 and 14.7 cm. In total, 3122 trees were harvested, resulting in 60% removal of stem number over all plots. The harvester achieved a mean productivity of 7.38 m PMH with 1.48 m PMH SEM, with stem volume having the major influence on harvesting productivity. Prior tree marking, topping and thinning method did not significantly affect productivity. Without prior tree marking by the foresters, harvesting removal was shifted toward lower diameters. Within the unmarked plots, 7.0% of the residual trees were damaged compared with 3.2% in marked plots.30â130â1","PeriodicalId":49520,"journal":{"name":"Silva Fennica","volume":"1 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66767318","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 9

Economic losses caused by tree species proportions and site type errors in forest management planning 森林经营规划中树种比例和立地类型错误造成的经济损失

IF 1.8 3区农林科学

Silva Fennica Pub Date : 2019-01-01 DOI: 10.14214/SF.10089

A. Haara, A. Kangas, S. Tuominen

{"title":"Economic losses caused by tree species proportions and site type errors in forest management planning","authors":"A. Haara, A. Kangas, S. Tuominen","doi":"10.14214/SF.10089","DOIUrl":"https://doi.org/10.14214/SF.10089","url":null,"abstract":"The aim of this study was to estimate economic losses, which are caused by forest inventory errors of tree species proportions and site types. Our study data consisted of ground truth data and four sets of erroneous tree species proportions. They reflect the accuracy of tree species proportions in four remote sensing data sets, namely 1) airborne laser scanning (ALS) with 2D aerial image, 2) 2D aerial image, 3) 3D and 2D aerial image data together and 4) satellite data. Furthermore, our study data consisted of one simulated site type data set. We used the erroneous tree species proportions to optimise the timing of forest harvests and compared that to the true optimum obtained with ground truth data. According to the results, the mean losses of Net Present Value (NPV) because of erroneous tree species proportions at an interest rate of 3% varied from 124.4 â¬ ha to 167.7 â¬ ha. The smallest losses were observed using tree species proportions predicted using ALS data and largest using satellite data. In those stands, respectively, in which tree species proportion errors actually caused economic losses, they were 468 â¬ ha on average with tree species proportions based on ALS data. In turn, site type errors caused only small losses. Based on this study, accurate tree species identification seems to be very important with respect to operational forest inventory.â1â1â1","PeriodicalId":49520,"journal":{"name":"Silva Fennica","volume":"1 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66767333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 10

Feedstock availability and moisture content data processing for multi-year simulation of forest biomass supply in energy production 用于能源生产中森林生物质供应多年模拟的原料有效性和水分含量数据处理

IF 1.8 3区农林科学

Silva Fennica Pub Date : 2019-01-01 DOI: 10.14214/sf.10147

M. Aalto, O. Korpinen, T. Ranta

{"title":"Feedstock availability and moisture content data processing for multi-year simulation of forest biomass supply in energy production","authors":"M. Aalto, O. Korpinen, T. Ranta","doi":"10.14214/sf.10147","DOIUrl":"https://doi.org/10.14214/sf.10147","url":null,"abstract":"Simulation and modeling have become more common in forest biomass studies. Dynamic simulation has been used to study the supply chain of forest biomass with numerous different models. A robust predictive multi-year model requires biomass availability data, where annual variation is included spatially and temporally. This can be done by using data from enterprises, but in some cases relevant data is not accessible. Another option is to use forest inventory data to estimate biomass availability, but this data must be processed in the correct form to be utilized in the model. This study developed a method for preparing forest inventory data for a multi-year simulation supply model using the theoretical availability of feedstock. Methods for estimating quality changes during roadside storage are also presented, including a possible parameter estimation to decrease the amount of data needed. The methods were tested case by case using the inventory database âBiomass Atlasâ and weather data from a weather station in Mikkeli, Finland. The data processing method for biomass allocation produced a reasonable quantity of stands and feedstock, having a realistic annual supply with variation for the demand point. The results of the study indicate that it is possible to estimate moisture content changes using weather data. The estimations decreased the accuracy of the model and, therefore, estimations should be kept minimal. The presented data preparation method can generate a supply of forest biomass for the simulation model, but the validity of the data must be ensured for correct model behavior.","PeriodicalId":49520,"journal":{"name":"Silva Fennica","volume":"1 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66767569","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Developing growth models for tree plantations using inadequate data – a case for Korean pine in Northeast China 利用不充分的数据开发人工林生长模型——以中国东北红松为例

IF 1.8 3区农林科学

Silva Fennica Pub Date : 2019-01-01 DOI: 10.14214/sf.10217

Xingji Jin, T. Pukkala, Fengri Li, Lihu Dong

引用次数: 5

Assessment of the CLASlite forest monitoring system in detecting disturbance from selective logging in the Selva Maya, Mexico 墨西哥玛雅森林选择性采伐干扰的CLASlite监测系统评估

IF 1.8 3区农林科学

Silva Fennica Pub Date : 2019-01-01 DOI: 10.14214/SF.10012

Irving Hernández-Gómez, C. Cerdán, A. Navarro-Martínez, D. Vázquez-Luna, Samaria Armenta-Montero, E. Ellis

{"title":"Assessment of the CLASlite forest monitoring system in detecting disturbance from selective logging in the Selva Maya, Mexico","authors":"Irving Hernández-Gómez, C. Cerdán, A. Navarro-Martínez, D. Vázquez-Luna, Samaria Armenta-Montero, E. Ellis","doi":"10.14214/SF.10012","DOIUrl":"https://doi.org/10.14214/SF.10012","url":null,"abstract":"Detecting and monitoring forest disturbance from selective logging is necessary to develop effective strategies and polices that conserve tropical forests and mitigate climate change. We assessed the potential of using the remote sensing tool, CLASlite forest monitoring system, to detect disturbance from timber harvesting in four community forests () of the Selva Maya on the Yucatan Peninsula, Mexico. Selective logging impacts (e.g. felling gaps, skid trails, logging roads and log landings) were mapped using GPS in the 2014 annual cutting areas (ACAs) of each ejido. We processed and analyzed two pre-harvest Landsat images (2001 and 2013) and one post-harvest image (November 2014) with the CLASlite system, producing maps of degraded, deforested and unlogged areas in each ACA. Based on reference points of disturbed (felling and skidding), deforested (log landings and roads) and unlogged areas in each ACA, we applied accuracy assessments which showed very low overall accuracies (<19.1%). Selective logging impacts, mainly from log landings and new logging road construction, were detected in only one ejido which had the highest logging intensity (7 m ha).ejidos3â1","PeriodicalId":49520,"journal":{"name":"Silva Fennica","volume":"1 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66766802","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

Impact of biomass harvesting on nitrogen concentration in the soil solution in hemiboreal woody ecosystems 生物量采伐对半北方木本生态系统土壤溶液氮浓度的影响

IF 1.8 3区农林科学

Silva Fennica Pub Date : 2019-01-01 DOI: 10.14214/sf.10016

Ivars Kļaviņš, A. Bārdule, Z. Lībiete, D. Lazdiņa, A. Lazdiņš

{"title":"Impact of biomass harvesting on nitrogen concentration in the soil solution in hemiboreal woody ecosystems","authors":"Ivars Kļaviņš, A. Bārdule, Z. Lībiete, D. Lazdiņa, A. Lazdiņš","doi":"10.14214/sf.10016","DOIUrl":"https://doi.org/10.14214/sf.10016","url":null,"abstract":"Considering the increasing use of wood biomass for energy and the related intensification of forest management, the impacts of different intensities of biomass harvesting on nutrient leaching risks must be better understood. Different nitrogen forms in the soil solution were monitored for 3 to 6 years after harvesting in hemiboreal forests in Latvia to evaluate the impacts of different biomass harvesting regimes on local nitrogen leaching risks, which potentially increase eutrophication in surface waters. In forestland dominated by Scots pine L. or Norway spruce L. (Karst.), the soil solution was sampled in: (i) stem-only harvesting (SOH), (ii) wholeâtree harvesting, with only slash removed (WTH), and (iii) wholeâtree harvesting, with both slash and stumps harvested (WTHâ+âSB), subplots. In agricultural land, sampling was performed in an initially fertilised hybrid aspen ( L.Ã Michx.) short-rotation coppice (SRC), where above-ground biomass was harvested. In forestland, soil solution N (nitrogen) concentrations were highest in the second and third year after harvesting. Mean annual values in WTH subplots of medium to high fertility sites exceeded the mean values in SOH subplots and control subplots (mature stand where no harvesting was performed) for the entire study period; the opposite trend was observed for the low-fertility site. Biomass harvesting in the hybrid aspen SRC only slightly affected NO-N (nitrate nitrogen) and NH-N (ammonium nitrogen) concentrations in the soil solution within 3 years after harvesting, but a significant decrease in the TN (total nitrogen) concentration in the soil solution was found in plots with additional N fertilisation performed once initially.Pinus sylvestrisPicea abiesPopulus tremulaP. tremuloides3â4+","PeriodicalId":49520,"journal":{"name":"Silva Fennica","volume":"1 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66766923","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Genetic variation in phenology and growth among and within Norway spruce populations from two altitudinal transects in Mid-Norway 挪威中部两个垂直样带挪威云杉种群间和种群内物候和生长的遗传变异

IF 1.8 3区农林科学

Silva Fennica Pub Date : 2019-01-01 DOI: 10.14214/sf.10076

T. Skrøppa, Arne Steffenrem

{"title":"Genetic variation in phenology and growth among and within Norway spruce populations from two altitudinal transects in Mid-Norway","authors":"T. Skrøppa, Arne Steffenrem","doi":"10.14214/sf.10076","DOIUrl":"https://doi.org/10.14214/sf.10076","url":null,"abstract":"Progenies from open pollinated cones collected in natural populations of Norway spruce ( (L. Karst.)) distributed along two altitudinal transects in Mid-Norway were tested in the nursery, in short term tests and in long-term field trials. The populations showed clinal variation related to the mean annual temperatures of the populations, with the earliest bud flush and cessation of shoot elongation and lowest height at age nine years for the high altitude populations. Within population variation was considerable as the narrow sense heritability for these traits was 0.67, 0.31 and 0.09 in one transect and 0.55, 0.18 and 0.14 in the other transect, respectively. Lammas shoots occurred in the short term trials with large variation in frequency between years. There was significant family variation for this trait, but also interactions between populations and year. The variance within populations was considerably larger in the populations from low altitude compared to the high-altitude populations. Significant genetic correlations between height and phenology traits and damage scores indicate that families flushing early and ceasing growth late were taller. Taller families also had higher frequencies of damages. Selection of the top 20% families for height growth in short term tests at age nine years gave a simulated gain of 11% increased height growth at age 18 years in long term trials at altitudes similar to those of origin of the populations. The gain was negative when high altitude populations were selected based on testing in the lowland.Picea abies","PeriodicalId":49520,"journal":{"name":"Silva Fennica","volume":"1 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66767231","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 12