D. Gafta, A. Schnitzler, D. Closset‐Kopp, V. Cristea
Neighbourhood models are useful tools for understanding the role of positive and negative interactions in maintaining the tree species diversity in mixed forests. Under such a presumption, we aimed at testing several hypotheses concerning the mechanisms of autogenic species coexistence in an old-growth, beech-fir-spruce stand, which is part of the Slătioara forest reserve (eastern Carpathians). Univariate/bivariate spatial point pattern analyses, the individual tree species-area relationship, the species mingling analysis and generalised linear mixed models of neighbour interference were applied on data concerning the position and allometry of all saplings and trees occurring within a 0.24 ha plot. The monospecific distribution of either beech or spruce saplings did not support the spatial segregation hypothesis. There was no evidence of conspecific negative distance dependence, as no spatial segregation was detected between the saplings and trees of any species. Within 4 m-neighbourhood, the beech saplings appeared as diversity accumulators, which might be indicative of indirect facilitation (e.g., herd protection hypothesis). At tree stage, none of the three species showed either accumulator or repeller patterns in their neighbourhood with respect to sapling species richness. Signals of positive and negative interspecific association were found in tree-sized beech (at scales of 10 to 20 m) and spruce (at scales of 4 to 17 m), respectively. The former, highly interspersed pattern is in accordance with the hypothesis of positive complementary effects, whereas the latter, poorly intermingled pattern is probably linked to the unexpected, positive neighbouring effect of spruce trees on the stem growth of their conspecific saplings. Such self-favouring process might be due to a facilitative below-ground mechanism. Conversely, the beech saplings were suppressed through interference from the neighbouring conspecific trees. The beech appears to be the key promoter of tree species coexistence in the study forest stand, in contrast to the low interspersion of spruce in the overstorey leading to lower local tree diversity.
{"title":"Neighbourhood-based evidence of tree diversity promotion by beech in an old-growth deciduous-coniferous mixed forest (Eastern Carpathians)","authors":"D. Gafta, A. Schnitzler, D. Closset‐Kopp, V. Cristea","doi":"10.15287/AFR.2020.2143","DOIUrl":"https://doi.org/10.15287/AFR.2020.2143","url":null,"abstract":"Neighbourhood models are useful tools for understanding the role of positive and negative interactions in maintaining the tree species diversity in mixed forests. Under such a presumption, we aimed at testing several hypotheses concerning the mechanisms of autogenic species coexistence in an old-growth, beech-fir-spruce stand, which is part of the Slătioara forest reserve (eastern Carpathians). Univariate/bivariate spatial point pattern analyses, the individual tree species-area relationship, the species mingling analysis and generalised linear mixed models of neighbour interference were applied on data concerning the position and allometry of all saplings and trees occurring within a 0.24 ha plot. The monospecific distribution of either beech or spruce saplings did not support the spatial segregation hypothesis. There was no evidence of conspecific negative distance dependence, as no spatial segregation was detected between the saplings and trees of any species. Within 4 m-neighbourhood, the beech saplings appeared as diversity accumulators, which might be indicative of indirect facilitation (e.g., herd protection hypothesis). At tree stage, none of the three species showed either accumulator or repeller patterns in their neighbourhood with respect to sapling species richness. Signals of positive and negative interspecific association were found in tree-sized beech (at scales of 10 to 20 m) and spruce (at scales of 4 to 17 m), respectively. The former, highly interspersed pattern is in accordance with the hypothesis of positive complementary effects, whereas the latter, poorly intermingled pattern is probably linked to the unexpected, positive neighbouring effect of spruce trees on the stem growth of their conspecific saplings. Such self-favouring process might be due to a facilitative below-ground mechanism. Conversely, the beech saplings were suppressed through interference from the neighbouring conspecific trees. The beech appears to be the key promoter of tree species coexistence in the study forest stand, in contrast to the low interspersion of spruce in the overstorey leading to lower local tree diversity.","PeriodicalId":48954,"journal":{"name":"Annals of Forest Research","volume":"64 1","pages":"13-30"},"PeriodicalIF":1.8,"publicationDate":"2021-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41638790","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}
S. Wickramarathna, J. Van Den Hoek, Bogdan M. Strimbu
Tree detection is the first step in the appraisal of a forest, especially when the focus is monitoring the growth of tree canopy. The acquisition of annual very high-resolution aerial images by the National Agriculture Imagery Program (NAIP) and their accessibility through Google Earth Engine (GEE) supports the delineation of tree canopies and change over time in a cost and time-effective manner. The objectives of this study are to develop an automated method to detect the crowns of individual western Juniper (Juniperus occidentalis) trees and to assess the change of forest cover from multispectral 1-meter resolution NAIP images collected from 2009 to 2016 in Oregon, USA. The Normalized Difference Vegetation Index (NDVI), Normalized Difference Water Index (NDWI), and Ratio Vegetation Index (RVI) were calculated from the NAIP images, in addition to the red-green-blue-near infrared bands. To identify the most suitable approach for individual tree crown identification, we created two training datasets: one considering yearly images separately and one merging all images, irrespective of the year. We segmented individual tree crowns using a random forest algorithm implemented in GEE and seven rasters, namely the reflectance of four spectral bands as recorded by the NAIP images (i.e., the red-green-blue-near infrared) and three calculated indices (i.e., NDVI, NDWI, and RVI). We compared the estimated location of the trees, computed as the centroid of the crown, with the visually identified treetops, which were considered as validation locations. We found that tree location errors were smaller when years were analyzed individually than by merging the years. Measurements of completeness (74%), correctness (94%), and mean accuracy detection (82 %) show promising performance of the random forest algorithm in crown delineation, considering that only four original input bands were used for crown segmentation. The change in the calculated crown area for western juniper follows a sinusoidal curve, with a decrease from 2011 to 2012 and an increase from 2012 to 2014. The proposed approach has the potential to estimate individual tree locations and forest cover area dynamics at broad spatial scales using regularly collected airborne imagery with easy-to-implement methods.
{"title":"Automated detection of individual juniper tree location and forest cover changes using Google Earth Engine","authors":"S. Wickramarathna, J. Van Den Hoek, Bogdan M. Strimbu","doi":"10.15287/AFR.2020.2145","DOIUrl":"https://doi.org/10.15287/AFR.2020.2145","url":null,"abstract":"Tree detection is the first step in the appraisal of a forest, especially when the focus is monitoring the growth of tree canopy. The acquisition of annual very high-resolution aerial images by the National Agriculture Imagery Program (NAIP) and their accessibility through Google Earth Engine (GEE) supports the delineation of tree canopies and change over time in a cost and time-effective manner. The objectives of this study are to develop an automated method to detect the crowns of individual western Juniper (Juniperus occidentalis) trees and to assess the change of forest cover from multispectral 1-meter resolution NAIP images collected from 2009 to 2016 in Oregon, USA. The Normalized Difference Vegetation Index (NDVI), Normalized Difference Water Index (NDWI), and Ratio Vegetation Index (RVI) were calculated from the NAIP images, in addition to the red-green-blue-near infrared bands. To identify the most suitable approach for individual tree crown identification, we created two training datasets: one considering yearly images separately and one merging all images, irrespective of the year. We segmented individual tree crowns using a random forest algorithm implemented in GEE and seven rasters, namely the reflectance of four spectral bands as recorded by the NAIP images (i.e., the red-green-blue-near infrared) and three calculated indices (i.e., NDVI, NDWI, and RVI). We compared the estimated location of the trees, computed as the centroid of the crown, with the visually identified treetops, which were considered as validation locations. We found that tree location errors were smaller when years were analyzed individually than by merging the years. Measurements of completeness (74%), correctness (94%), and mean accuracy detection (82 %) show promising performance of the random forest algorithm in crown delineation, considering that only four original input bands were used for crown segmentation. The change in the calculated crown area for western juniper follows a sinusoidal curve, with a decrease from 2011 to 2012 and an increase from 2012 to 2014. The proposed approach has the potential to estimate individual tree locations and forest cover area dynamics at broad spatial scales using regularly collected airborne imagery with easy-to-implement methods.","PeriodicalId":48954,"journal":{"name":"Annals of Forest Research","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2021-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49330268","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}
Nature reserves harbor considerable richness and diversity of saproxylic organisms since dead wood is preserved in situ , this being also the case of Voivodeasa beech-spruce-fir forest in North-Eastern Romania, the area investigated under the present research. The employed sampling design consisted in 20 flight interception traps placed in a square grid (100 x 100 m). The beetle content of the traps was collected every two weeks, from May to September. The number of intercepted beetles reached 13,554 individuals, of which 7,174 individuals (assigned to 336 species placed in 217 genera and 58 families) were identified at species level and 6,390 individuals, at genus or family level. The majority of the identified species were obligate saproxylic species (217 species). However, the unexpected high species richness corresponded to an area with modest representation of deadwood due to previous status of commercial forest. The identified beetles were members of different habitat-guilds depending on what type of substrate they colonize: recently dead wood (23%), decomposed dead wood (41%), wood inhabiting fungi (34%) and tree-hollow detritus (2%). According to their trophic position, the identified saproxylic beetles pertained to the following guilds: xylophagous (40%), mycetophagous (39%), predatory (14%), and species relying on other food resources (5%). Non-metric Multidimensional Scaling ordination using Bray-Curtis distance, performed to compare the saproxylic beetles’community at different sampling dates across the vegetation season suggested that species turn-over took place in the time window of one month. The analysis of abundance/dominance structure of the saproxylic beetle community employing classical community indices (abundance, dominance, constancy and Dzuba index) showed that 7% of the species were abundant, and 68% were rare, Fisher’s log series fitting the distribution of abundances. In terms of constancy, 11% were eu-constant and 62% - accidental species. Considering the dominance, only 0.4% represented eu-dominant species while 89% were sub-recedent species. According to Dzuba ecological significance index, four species were characteristic for the saproxylic beetle community: Ptilinus pecticornis, Enicmus rugosus, Cis rugulosus and Taphorychus bicolor , most of the identified species being accessory or accidental (33% and 65%). PCA ordination performed on abundance constancy, dominance and ecological significance scores, showed that all indices were highly correlated with PC1 and further testing using multivariate regression with dominance held as independent variable, showed high correlation among indices. Species ranked according to these indices as rare, accidental or accesory clustered separatelly in the ordination space while dominant and eu-dominant species established another distinct cluster. Species richness estimation based on Chao 1 nonparametric index exceeded the observed richness of saproxylic beetles (estimated numbe
{"title":"The diversity of saproxylic beetles’ from the Natural Reserve Voievodeasa forest, North-Eastern Romania","authors":"N. Olenici, E. Fodor","doi":"10.15287/AFR.2020.2144","DOIUrl":"https://doi.org/10.15287/AFR.2020.2144","url":null,"abstract":"Nature reserves harbor considerable richness and diversity of saproxylic organisms since dead wood is preserved in situ , this being also the case of Voivodeasa beech-spruce-fir forest in North-Eastern Romania, the area investigated under the present research. The employed sampling design consisted in 20 flight interception traps placed in a square grid (100 x 100 m). The beetle content of the traps was collected every two weeks, from May to September. The number of intercepted beetles reached 13,554 individuals, of which 7,174 individuals (assigned to 336 species placed in 217 genera and 58 families) were identified at species level and 6,390 individuals, at genus or family level. The majority of the identified species were obligate saproxylic species (217 species). However, the unexpected high species richness corresponded to an area with modest representation of deadwood due to previous status of commercial forest. The identified beetles were members of different habitat-guilds depending on what type of substrate they colonize: recently dead wood (23%), decomposed dead wood (41%), wood inhabiting fungi (34%) and tree-hollow detritus (2%). According to their trophic position, the identified saproxylic beetles pertained to the following guilds: xylophagous (40%), mycetophagous (39%), predatory (14%), and species relying on other food resources (5%). Non-metric Multidimensional Scaling ordination using Bray-Curtis distance, performed to compare the saproxylic beetles’community at different sampling dates across the vegetation season suggested that species turn-over took place in the time window of one month. The analysis of abundance/dominance structure of the saproxylic beetle community employing classical community indices (abundance, dominance, constancy and Dzuba index) showed that 7% of the species were abundant, and 68% were rare, Fisher’s log series fitting the distribution of abundances. In terms of constancy, 11% were eu-constant and 62% - accidental species. Considering the dominance, only 0.4% represented eu-dominant species while 89% were sub-recedent species. According to Dzuba ecological significance index, four species were characteristic for the saproxylic beetle community: Ptilinus pecticornis, Enicmus rugosus, Cis rugulosus and Taphorychus bicolor , most of the identified species being accessory or accidental (33% and 65%). PCA ordination performed on abundance constancy, dominance and ecological significance scores, showed that all indices were highly correlated with PC1 and further testing using multivariate regression with dominance held as independent variable, showed high correlation among indices. Species ranked according to these indices as rare, accidental or accesory clustered separatelly in the ordination space while dominant and eu-dominant species established another distinct cluster. Species richness estimation based on Chao 1 nonparametric index exceeded the observed richness of saproxylic beetles (estimated numbe","PeriodicalId":48954,"journal":{"name":"Annals of Forest Research","volume":"64 1","pages":"31-60"},"PeriodicalIF":1.8,"publicationDate":"2021-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42727601","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}
T. Poletto, M. Muniz, V. S. Fantinel, Laís da Silva Martello, L. G. Savian, R. Harakava, E. Guatimosim, I. Poletto, V. M. Stefenon
Due to the increase in pecan nuts demand, plantation areas are expected to expand around the world and more frequent epidemics caused by fungal pathogens may occur in orchards and nurseries. Ragnhildiana diffusa is a pathogenic fungus reported as causing brown leaf spots in pecan in Mexico, South Africa, and the U.S.A. The scarcity of comprehensive information in symptoms on the host and morphology of the fungus lead this disease to be initially incorrectly identified in Brazil. In this study, we employed different approaches to characterize the pathogen morphology and pathogenicity and to molecularly identify the organism causing brown leaf spots in 10 different orchards in southern Brazil. A phylogenetic analysis based on the ITS and the LSU gene sequences confirmed R. diffusa as the causal pathogen of the disease in all orchards. Inoculation tests on healthy leaflets confirmed that all sampled isolates were pathogenic, although some variation in their virulence was observed. Variation in the morphology of the asexual stage was observed among and within isolates. The accurate and prompt identification of the disease may assist controlling further spread of the pathogen into orchards and nurseries still free of the disease in South America.
{"title":"Characterization of the brown leaf spots pathosystem in Brazilian pecan orchards: pathogen morphology and molecular identification","authors":"T. Poletto, M. Muniz, V. S. Fantinel, Laís da Silva Martello, L. G. Savian, R. Harakava, E. Guatimosim, I. Poletto, V. M. Stefenon","doi":"10.15287/AFR.2020.1957","DOIUrl":"https://doi.org/10.15287/AFR.2020.1957","url":null,"abstract":"Due to the increase in pecan nuts demand, plantation areas are expected to expand around the world and more frequent epidemics caused by fungal pathogens may occur in orchards and nurseries. Ragnhildiana diffusa is a pathogenic fungus reported as causing brown leaf spots in pecan in Mexico, South Africa, and the U.S.A. The scarcity of comprehensive information in symptoms on the host and morphology of the fungus lead this disease to be initially incorrectly identified in Brazil. In this study, we employed different approaches to characterize the pathogen morphology and pathogenicity and to molecularly identify the organism causing brown leaf spots in 10 different orchards in southern Brazil. A phylogenetic analysis based on the ITS and the LSU gene sequences confirmed R. diffusa as the causal pathogen of the disease in all orchards. Inoculation tests on healthy leaflets confirmed that all sampled isolates were pathogenic, although some variation in their virulence was observed. Variation in the morphology of the asexual stage was observed among and within isolates. The accurate and prompt identification of the disease may assist controlling further spread of the pathogen into orchards and nurseries still free of the disease in South America.","PeriodicalId":48954,"journal":{"name":"Annals of Forest Research","volume":"64 1","pages":"75-86"},"PeriodicalIF":1.8,"publicationDate":"2021-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44057473","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}
E. Salerni, D. Barbato, C. Cazau, L. Gardin, G. Henson, P. Leonardi, A. Tomao, C. Perini
As a man-induced disturbance of forest ecosystems, thinning may affect biodiversity and other related ecological functions including fungal dynamics. In this context, a multidisciplinary EU-Life project was established in 2014 to evaluate the application of selective thinning in two Pinus nigra plantations areas of the Apennines (Monte Amiata and Pratomagno, Tuscany, Italy). Selective thinning had the aim to improve stands stability and growth rates, taking also into account the various components of soil biodiversity (flora, fungi, mesofauna, nematodes, microarthropods and bacteria). Here we present mushroom fruiting patterns previous to treatment in 2014 and the effect following the application of forest management (selective thinning and traditional thinning from below) in 2018. Boxplots were used to graphically represent intra and inter annual variations in species richness and abundance, while Principal Coordinates Analyses and multi-response permutation procedures based on Bray-Curtis dissimilarity matrix were applied to evaluate turnover in species composition before the management and after 4 years. A significant reduction of fungal richness and abundance after 4 years thinning impact was lacking in both study areas, testifying a certain degree of resistance and/or resilience of mushroom fruiting to forest management-related anthropogenic disturbance. Considering each study site separately, Monte Amiata and Pratomagno did not show one uniform trend but differed significantly in their response to management: while in Pratomagno relevant inter-annual differences were present only in a few cases, an underlining significant variation both for species richness and abundance was registered in Monte Amiata for all treatment types among years (inter-annual variation) but not within each year (intra-annual variation). Only in Pratomagno turnover in species composition in selective thinning differed somewhat from the traditional treatment in 2018, showing that a process is underlying but still potentially masked by other variables. Due to the nature of macrofungi, a longer study period (more than 4 years post treatment impact) as well as the application of a more intense forest management, could be necessary to highlight and disentangle any possible trends in fungal fruiting in artificial stands
{"title":"Selective thinning to enhance soil biodiversity in artificial black pine stands - what happens to mushroom fruiting?","authors":"E. Salerni, D. Barbato, C. Cazau, L. Gardin, G. Henson, P. Leonardi, A. Tomao, C. Perini","doi":"10.15287/AFR.2020.2006","DOIUrl":"https://doi.org/10.15287/AFR.2020.2006","url":null,"abstract":"As a man-induced disturbance of forest ecosystems, thinning may affect biodiversity and other related ecological functions including fungal dynamics. In this context, a multidisciplinary EU-Life project was established in 2014 to evaluate the application of selective thinning in two Pinus nigra plantations areas of the Apennines (Monte Amiata and Pratomagno, Tuscany, Italy). Selective thinning had the aim to improve stands stability and growth rates, taking also into account the various components of soil biodiversity (flora, fungi, mesofauna, nematodes, microarthropods and bacteria). Here we present mushroom fruiting patterns previous to treatment in 2014 and the effect following the application of forest management (selective thinning and traditional thinning from below) in 2018. Boxplots were used to graphically represent intra and inter annual variations in species richness and abundance, while Principal Coordinates Analyses and multi-response permutation procedures based on Bray-Curtis dissimilarity matrix were applied to evaluate turnover in species composition before the management and after 4 years. A significant reduction of fungal richness and abundance after 4 years thinning impact was lacking in both study areas, testifying a certain degree of resistance and/or resilience of mushroom fruiting to forest management-related anthropogenic disturbance. Considering each study site separately, Monte Amiata and Pratomagno did not show one uniform trend but differed significantly in their response to management: while in Pratomagno relevant inter-annual differences were present only in a few cases, an underlining significant variation both for species richness and abundance was registered in Monte Amiata for all treatment types among years (inter-annual variation) but not within each year (intra-annual variation). Only in Pratomagno turnover in species composition in selective thinning differed somewhat from the traditional treatment in 2018, showing that a process is underlying but still potentially masked by other variables. Due to the nature of macrofungi, a longer study period (more than 4 years post treatment impact) as well as the application of a more intense forest management, could be necessary to highlight and disentangle any possible trends in fungal fruiting in artificial stands","PeriodicalId":48954,"journal":{"name":"Annals of Forest Research","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2020-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46028769","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}
Elucidating variability in nutrient resorption and carbon (C), nitrogen (N) and phosphorus (P) stoichiometry is important for holistically understanding plant approaches to nutrient adaption. However, the patterns of these phenomena in afforested regions of the Beijing Plain have been ignored. Herein, we assessed patterns of leaf and litter C, N, and P stoichiometry and nutrient resorption in Robinia pseudoacacia L., Ailanthus altissima (Mill.) Swingle, and Salix matsudana Koidz. forests in afforested areas in Beijing, China. We found that the plantation growth of R. pseudoacacia and S. matsudana was mainly limited by P nutrients. Both the N and P in the fresh leaves of R. pseudoacacia were significantly higher than those in the fresh leaves of S. matsudana and A. altissima, indicating that the N resorption efficiency (NRE) of R. pseudoacacia was higher. However, the P resorption efficiency (PRE) was significantly correlated with the leaf P nutrients in the R. pseudoacacia and A. altissima forests. Except for the significant correlation between the N content of fresh leaves and the AN content in soil, there were no significant correlations between the leaf C, N and P contents and the contents of these nutrients in the soil. These results suggested that of the factors studied, leaf P stoichiometry and PRE were more responsive indicators of the afforestation area on the Beijing Plain. Together, our data indicated that P deficiency is an important factor for the forests on the Beijing Plain and that the ability of afforested areas to adapt to barren land through nutrient resorption is gradually weakened and the N and P nutrient preservation ability is reduced over time. We thus clarified the nutrient resorption and leaf P and N patterns for the three forests studied. The findings have important implications for the application of P fertilizer, which must be conducted in a timely fashion to ensure that nutrient addition meets the nutritional needs of the plants.
{"title":"Nutrient resorption efficiency of three tree species in Beijing plain afforestation and its C:N:P stoichiometry","authors":"Yuanhao Wu, Jun Jiang, Beibei Chen, Yucun Hu","doi":"10.15287/AFR.2020.1969","DOIUrl":"https://doi.org/10.15287/AFR.2020.1969","url":null,"abstract":"Elucidating variability in nutrient resorption and carbon (C), nitrogen (N) and phosphorus (P) stoichiometry is important for holistically understanding plant approaches to nutrient adaption. However, the patterns of these phenomena in afforested regions of the Beijing Plain have been ignored. Herein, we assessed patterns of leaf and litter C, N, and P stoichiometry and nutrient resorption in Robinia pseudoacacia L., Ailanthus altissima (Mill.) Swingle, and Salix matsudana Koidz. forests in afforested areas in Beijing, China. We found that the plantation growth of R. pseudoacacia and S. matsudana was mainly limited by P nutrients. Both the N and P in the fresh leaves of R. pseudoacacia were significantly higher than those in the fresh leaves of S. matsudana and A. altissima, indicating that the N resorption efficiency (NRE) of R. pseudoacacia was higher. However, the P resorption efficiency (PRE) was significantly correlated with the leaf P nutrients in the R. pseudoacacia and A. altissima forests. Except for the significant correlation between the N content of fresh leaves and the AN content in soil, there were no significant correlations between the leaf C, N and P contents and the contents of these nutrients in the soil. These results suggested that of the factors studied, leaf P stoichiometry and PRE were more responsive indicators of the afforestation area on the Beijing Plain. Together, our data indicated that P deficiency is an important factor for the forests on the Beijing Plain and that the ability of afforested areas to adapt to barren land through nutrient resorption is gradually weakened and the N and P nutrient preservation ability is reduced over time. We thus clarified the nutrient resorption and leaf P and N patterns for the three forests studied. The findings have important implications for the application of P fertilizer, which must be conducted in a timely fashion to ensure that nutrient addition meets the nutritional needs of the plants.","PeriodicalId":48954,"journal":{"name":"Annals of Forest Research","volume":"1 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2020-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41536144","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}
Sergio Fantini, Mauro Fois, P. Casula, G. Fenu, G. Calvia, G. Bacchetta
Mediterranean forests have been altered by several human activities. Consequently, relatively intact forests that have been unmodified by humans for a relatively long time (i.e., old-growth forests) are often reduced to isolated and fragmented stands. However, despite their high conservation value, little is known about their features and even presence several Mediterranean areas. First steps of their investigation are based on the identification of old-growth features such as amount of large‐size and old trees, tree species composition, canopy heterogeneity, occurrence and amount of deadwood. The Structural Heterogeneity Index (SHI) is commonly used to summarise features of old-growthness in one single value. Here, the SHI was derived for 68 plots included in 45 forest stands within the 4,297 km2 of territory that is covered by forests in Sardinia. SHI values were affected by variables that are likely to be related to forest age and structural complexity, such as presence of cerambycids, canopy cover, forest layers, location and three old-growthness classes. Results confirm a high structural variability among forests with old-growth features, determined by the presence, or lack, of given living and deadwood features. Our findings identified, for the first time, most of the forest stands that need special protection in Sardinia for the presence of old-growth features. In this sense, the SHI was confirmed useful for improving their management and conservation, although more specific and deeper studies are necessary for better understanding their species composition and dynamics.
{"title":"Structural heterogeneity and old-growthness: A first regional-scale assessment of Sardinian forests","authors":"Sergio Fantini, Mauro Fois, P. Casula, G. Fenu, G. Calvia, G. Bacchetta","doi":"10.15287/AFR.2020.1968","DOIUrl":"https://doi.org/10.15287/AFR.2020.1968","url":null,"abstract":"Mediterranean forests have been altered by several human activities. Consequently, relatively intact forests that have been unmodified by humans for a relatively long time (i.e., old-growth forests) are often reduced to isolated and fragmented stands. However, despite their high conservation value, little is known about their features and even presence several Mediterranean areas. First steps of their investigation are based on the identification of old-growth features such as amount of large‐size and old trees, tree species composition, canopy heterogeneity, occurrence and amount of deadwood. The Structural Heterogeneity Index (SHI) is commonly used to summarise features of old-growthness in one single value. Here, the SHI was derived for 68 plots included in 45 forest stands within the 4,297 km2 of territory that is covered by forests in Sardinia. SHI values were affected by variables that are likely to be related to forest age and structural complexity, such as presence of cerambycids, canopy cover, forest layers, location and three old-growthness classes. Results confirm a high structural variability among forests with old-growth features, determined by the presence, or lack, of given living and deadwood features. Our findings identified, for the first time, most of the forest stands that need special protection in Sardinia for the presence of old-growth features. In this sense, the SHI was confirmed useful for improving their management and conservation, although more specific and deeper studies are necessary for better understanding their species composition and dynamics.","PeriodicalId":48954,"journal":{"name":"Annals of Forest Research","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2020-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41790198","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}
K. Jadwiszczak, L. Vetchinnikova, Agnieszka Bona, Łukasz Tyburski, T. Kuznetsova, V. Isidorov
Trees and shrubs belonging to the Betula L. genus seem to represent one of the most confused interspecific relationships, and hybridization is considered to be one of the main factors responsible for the substantial genetic and morphological variation of birches. In the present investigation, the internal transcribed spacer ITS1 and ITS2 regions of nuclear ribosomal DNA, nuclear alcohol dehydrogenase (ADH) gene sequences and amplified fragment length polymorphisms (AFLPs) as well as the Atkinson discriminant function (ADF) of leaf morphology were used to verify hypotheses concerning the origin of the dark barked Betula obscura and B. pendula var. carelica with the patterned wood. Both plants were considered by different authors to be distinct species, intraspecific forms of common B. pendula or B. pubescens, or hybrid taxa between B. pendula and B. pubescens. In the phylogenetic trees, the ITS and ADH gene sequences of both B. obscura and B. pendula var. carelica clustered with those of B. pendula, whereas B. pubescens trees were somewhat distinct. In turn, the AFLPs revealed genetic similarity of B. pendula var. carelica to both frequent species, whereas B. obscura was clearly distinct from other birches. Values of the ADF indices of the rare birches were typical for B. pendula. In the light of the results obtained, we imply that B. obscura and B. pendula var. carelica represent an intraspecific variation of B. pendula, they are neither intraspecific taxa of B. pubescens nor hybrid species between the common birches. Different grouping of B. obscura in the AFLPs and DNA sequences analyses is likely a result of an unreliable phylogenetic signal of the former molecular markers.
{"title":"Analyses of molecular markers and leaf morphology of two rare birches, Betula obscura and B. pendula var. carelica","authors":"K. Jadwiszczak, L. Vetchinnikova, Agnieszka Bona, Łukasz Tyburski, T. Kuznetsova, V. Isidorov","doi":"10.15287/AFR.2020.1973","DOIUrl":"https://doi.org/10.15287/AFR.2020.1973","url":null,"abstract":"Trees and shrubs belonging to the Betula L. genus seem to represent one of the most confused interspecific relationships, and hybridization is considered to be one of the main factors responsible for the substantial genetic and morphological variation of birches. In the present investigation, the internal transcribed spacer ITS1 and ITS2 regions of nuclear ribosomal DNA, nuclear alcohol dehydrogenase (ADH) gene sequences and amplified fragment length polymorphisms (AFLPs) as well as the Atkinson discriminant function (ADF) of leaf morphology were used to verify hypotheses concerning the origin of the dark barked Betula obscura and B. pendula var. carelica with the patterned wood. Both plants were considered by different authors to be distinct species, intraspecific forms of common B. pendula or B. pubescens, or hybrid taxa between B. pendula and B. pubescens. In the phylogenetic trees, the ITS and ADH gene sequences of both B. obscura and B. pendula var. carelica clustered with those of B. pendula, whereas B. pubescens trees were somewhat distinct. In turn, the AFLPs revealed genetic similarity of B. pendula var. carelica to both frequent species, whereas B. obscura was clearly distinct from other birches. Values of the ADF indices of the rare birches were typical for B. pendula. In the light of the results obtained, we imply that B. obscura and B. pendula var. carelica represent an intraspecific variation of B. pendula, they are neither intraspecific taxa of B. pubescens nor hybrid species between the common birches. Different grouping of B. obscura in the AFLPs and DNA sequences analyses is likely a result of an unreliable phylogenetic signal of the former molecular markers.","PeriodicalId":48954,"journal":{"name":"Annals of Forest Research","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2020-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42963504","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}
R. Spinelli, R. Visser, N. Magagnotti, C. Lombardini
t Integration of technology is commonplace in forestry equipment supporting higher levels of automation and efficiency. For technology adoption to be successful it must demonstrate improvement in productivity, cost–effectiveness or in human factors and ergonomics. Cable yarding lends itself to automation with repetitive machine movement along a fixed corridor, as established by the skyline. This study aimed at investigating the difference in productivity between the two possible settings (manual and automated) of a Valentini V850 yarder equipped with automatic path programming, with a Bergwald 3-t carriage and radio controlled chokers. The study took place in the northern Italian Alpine eastern region over a period of 8 days on two separate corridors, resulting in 280 measured cycles split between manual and automated. Results in terms of absolute numbers were very close for the two system options, but significant differences were found. For example, inhaul time was longer, but outhaul time shorter for the automated system. Productivity ranged from 8.2 to 13.3 m3 PMH-1, and cost from approximately 20 to 30 € m-3. The automated system did achieve a significantly higher productivity, but differences declined with extraction distance. When that was combined with the slightly higher cost for the automated system, the automated system was more cost-effective on extraction distances less than 200 m, and the manual system on longer distances.
{"title":"The effect of partial automation on the productivity and cost of a mobile tower yarder","authors":"R. Spinelli, R. Visser, N. Magagnotti, C. Lombardini","doi":"10.15287/AFR.2020.1883","DOIUrl":"https://doi.org/10.15287/AFR.2020.1883","url":null,"abstract":"t Integration of technology is commonplace in forestry equipment supporting higher levels of automation and efficiency. For technology adoption to be successful it must demonstrate improvement in productivity, cost–effectiveness or in human factors and ergonomics. Cable yarding lends itself to automation with repetitive machine movement along a fixed corridor, as established by the skyline. This study aimed at investigating the difference in productivity between the two possible settings (manual and automated) of a Valentini V850 yarder equipped with automatic path programming, with a Bergwald 3-t carriage and radio controlled chokers. The study took place in the northern Italian Alpine eastern region over a period of 8 days on two separate corridors, resulting in 280 measured cycles split between manual and automated. Results in terms of absolute numbers were very close for the two system options, but significant differences were found. For example, inhaul time was longer, but outhaul time shorter for the automated system. Productivity ranged from 8.2 to 13.3 m3 PMH-1, and cost from approximately 20 to 30 € m-3. The automated system did achieve a significantly higher productivity, but differences declined with extraction distance. When that was combined with the slightly higher cost for the automated system, the automated system was more cost-effective on extraction distances less than 200 m, and the manual system on longer distances.","PeriodicalId":48954,"journal":{"name":"Annals of Forest Research","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2020-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47848305","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}
Mihai Fedorca, O. Ionescu, N. Șofletea, A. Fedorca, A. Curtu, G. Ionescu
Romania holds the most extensive mountain range with oldgrowth forests, in which both habitat surface and capercaillie (Tetrao urogallus) numbers are ones of the highest in Central and Eastern Europe. While previous genetic studies have found that the individuals located in different European mountain ranges are isolated and have highlighted that the species is declining. Here, we are aiming to assess the genetic structure of capercaillie in Romania by genotyping 137 samples collected in the field with 9 STR markers. Expected heterozygosity was 0.586, whereas observed heterozygosity values were 0.859. Population structure analyses indicated weak population differentiation and suggested that sufficient gene flow exists among individuals sampled in different mountain regions. We did not find evidence for a past genetic bottleneck. Our findings contain important information to wildlife managers to focus conservation efforts in areas such as Curvature Carpathians, which serve as a connectivity corridor to avoid eroding the extent or quality of habitat and to prevent further fragmentation.
{"title":"Assessing the genetic structure of capercaillie (Tetrao urogallus) in Romania","authors":"Mihai Fedorca, O. Ionescu, N. Șofletea, A. Fedorca, A. Curtu, G. Ionescu","doi":"10.15287/AFR.2020.2025","DOIUrl":"https://doi.org/10.15287/AFR.2020.2025","url":null,"abstract":"Romania holds the most extensive mountain range with oldgrowth forests, in which both habitat surface and capercaillie (Tetrao urogallus) numbers are ones of the highest in Central and Eastern Europe. While previous genetic studies have found that the individuals located in different European mountain ranges are isolated and have highlighted that the species is declining. Here, we are aiming to assess the genetic structure of capercaillie in Romania by genotyping 137 samples collected in the field with 9 STR markers. Expected heterozygosity was 0.586, whereas observed heterozygosity values were 0.859. Population structure analyses indicated weak population differentiation and suggested that sufficient gene flow exists among individuals sampled in different mountain regions. We did not find evidence for a past genetic bottleneck. Our findings contain important information to wildlife managers to focus conservation efforts in areas such as Curvature Carpathians, which serve as a connectivity corridor to avoid eroding the extent or quality of habitat and to prevent further fragmentation.","PeriodicalId":48954,"journal":{"name":"Annals of Forest Research","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2020-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42526534","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}
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