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1
Zhu, Yu, Shuguang Liu, Wende Yan, et al. "Impact of Ice-Storms and Subsequent Salvage Logging on the Productivity of Cunninghamia lanceolata (Chinese Fir) Forests." Forests 13, no. 2 (2022): 296. http://dx.doi.org/10.3390/f13020296.
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The impacts of ice-storms on forests have received growing attention in recent years. Although there is a wide agreement that ice-storms significantly affect forest structure and functions, how frequent ice-storms and subsequent salvage logging impact productivity of subtropical coniferous forests in the future still remains poorly understood. In this study, we used the Ecosystem Demography model, Version 2.2 (ED-2.2), to project the impact of salvage logging of ice-storm-damaged trees on the productivity of Cunninghamia lanceolata-dominated coniferous forest and C. lanceolata-dominated mixed coniferous and broadleaved forests. The results show that forest productivity recovery is delayed in coniferous forests when there is no shade-tolerant broadleaved species invasion after ice-storms, and C. lanceolata could continue to dominate the canopy in the mixed coniferous and broadleaved forests under high-frequency ice-storms and subsequent salvage logging. The resistance and resilience of the mixed coniferous and broadleaved forests to high-frequency ice-storms and subsequent salvage logging were stronger compared to coniferous forests. Although conifers could continue to dominate the canopy under shade-tolerant broadleaved species invasion, we could not rule out the possibility of a future forest community dominated by shade-tolerant broadleaf trees because there were few coniferous saplings and shade-tolerant broadleaf species dominated the understory. Our results highlight that post-disaster forest management should be continued after high-frequency ice-storms and subsequent salvage logging in C. lanceolata forests to prevent possible shade-tolerant, late successional broadleaf trees from dominating the canopy in the future.
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Yun, Yeong-Bae, Myeongbin Park, Yi Lee, and Yurry Um. "Investigation of Growth and Ginsenoside Content of Wild-Simulated Ginseng Cultivated in Different Vegetation Environments for Establishing a Plant Growth Model." Plants 14, no. 6 (2025): 906. https://doi.org/10.3390/plants14060906.
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Wild-simulated ginseng (WSG, Panax ginseng C.A. Meyer) is one of the most valuable medicinal plants in the world. This study aimed to investigate the correlation between growth and ginsenoside content of WSG in two different cultivation environments: coniferous and mixed forests. The results showed that air temperature, soil moisture content, and solar radiation were higher in mixed forest than in coniferous forest. Regarding soil properties, electrical conductivity, organic matter, total nitrogen, exchangeable potassium, and magnesium were higher in mixed forest than in coniferous forest. However, exchangeable sodium was lower in mixed forest than in coniferous forest. The analysis of growth characteristics revealed that the number of leaflets was significantly higher in WSG cultivated in mixed forest than in WSG cultivated in coniferous forest, whereas rhizome length, root diameter, root weight, and dry weight were significantly higher in coniferous forest. In contrast, total ginsenoside content and the content of each ginsenoside were much higher in WSG cultivated in mixed forest than in WSG cultivated in coniferous forest. The growth of WSG showed significantly positive correlations with electrical conductivity, organic matter, total nitrogen, exchangeable cations (K+, Mg2+, Na+), and cation exchange capacity. The number of leaflets per stem showed significantly positive correlations with six ginsenosides, whereas petiole length showed significantly negative correlations with mRb1, mRc, and Rb1. In conclusion, growth characteristics of WSG were higher in coniferous forest, but ginsenoside contents were higher in mixed forest. These results might be helpful for establishing the most optimal growth model of WSG, which is affected by various environmental factors.
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Danneyrolles, Victor, Osvaldo Valeria, Ibrahim Djerboua, Sylvie Gauthier, and Yves Bergeron. "How Initial Forest Cover, Site Characteristics and Fire Severity Drive the Dynamics of the Southern Boreal Forest." Remote Sensing 12, no. 23 (2020): 3957. http://dx.doi.org/10.3390/rs12233957.
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Forest fires are a key driver of boreal landscape dynamics and are expected to increase with climate change in the coming decades. A profound understanding of the effects of fire upon boreal forest dynamics is thus critically needed for our ability to manage these ecosystems and conserve their services. In the present study, we investigate the long-term post-fire forest dynamics in the southern boreal forests of western Quebec using historical aerial photographs from the 1930s, alongside with modern aerial photographs from the 1990s. We quantify the changes in forest cover classes (i.e., conifers, mixed and broadleaved) for 16 study sites that were burned between 1940 and 1970. We then analyzed how interactions between pre-fire forest composition, site characteristics and a fire severity weather index (FSWI) affected the probability of changes in forest cover. In the 1930s, half of the cover of sampled sites were coniferous while the other half were broadleaved or mixed. Between the 1930s and the 1990s, 41% of the areas maintained their initial cover while 59% changed. The lowest probability of changes was found with initial coniferous cover and well drained till deposits. Moreover, an important proportion of 1930s broadleaved/mixed cover transitioned to conifers in the 1990s, which was mainly associated with high FSWI and well-drained deposits. Overall, our results highlight a relatively high resistance and resilience of southern boreal coniferous forests to fire, which suggest that future increase in fire frequency may not necessarily result in a drastic loss of conifers.
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Li, Zixing, Xinghao Wang, Yuan Huang, Xinrong Yang, Ran Wang, and Mengtao Zhang. "Increasing the Proportion of Broadleaf Species in Mixed Conifer-Broadleaf Forests Improves Understory Plant Composition and Promotes Soil Carbon Fixation." Plants 14, no. 9 (2025): 1392. https://doi.org/10.3390/plants14091392.
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Understory vegetation is an important component of forest ecosystems, and the supply of nutrients in the soil is related to the growth and development of soil microorganisms and understory plants. The effects of different tree species composition ratios in the forest on the process of soil microbial community assembly are not clear in the existing studies, and the factors influencing the differences in the abundance of understory plants under different forest canopy compositions and their mechanisms of action have not yet been clearly explained. In this study, two types of pure forests (PFP and PFQ) and two types of mixed forests (MF and MPQ) were selected from the Zhongcun Forestry, and the soil characteristics, soil microbial community assembly process, and understory plant community abundance, composition, and β-diversity were analyzed for the different forest types. The results showed that changes in the proportion of broadleaf and coniferous species in the forest could lead to changes in the community assembly process of soil fungi, and that the fungal assembly process in the mixed forest was mainly related to dispersal limitation. Compared with pure forests that were exclusively coniferous or exclusively broadleaf, mixed coniferous and broadleaf forests had a higher abundance of understory plants and a more stable forest community composition. In mixed forests, forests with a large proportion of broadleaf arbors had more available resources in the soil, soil pH was closer to neutral, and soil C was less likely to be lost compared to forests with a large proportion of conifers.
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Wang, Hongrong, Haoquan Chen, Hanmin Sheng, Kai Chen, Chen Dong, and Zhiqiang Min. "Fuel Load Models for Different Tree Vegetation Types in Sichuan Province Based on Machine Learning." Forests 16, no. 1 (2024): 42. https://doi.org/10.3390/f16010042.
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(1) Objective: To improve forest fire prevention, this study provides a reference for forest fire risk assessment in Sichuan Province. (2) Methods: This research focuses on various forest vegetation types in Sichuan Province. Given data from 6848 sample plots, five machine learning models—random forest, extreme gradient boosting (XGBoost), k-nearest neighbors, support vector machine, and stacking ensemble (Stacking)—were employed. Bayesian optimization was utilized for hyperparameter tuning, resulting in machine learning models for predicting forest fuel loads (FLs) across five different vegetation types. (3) Results: The FL model incorporates not only vegetation characteristics but also site conditions and climate data. Feature importance analysis indicated that structural factors (e.g., canopy closure, diameter at breast height, and tree height) dominated in cold broadleaf, subtropical broadleaf, and subtropical mixed forests, while climate factors (e.g., mean annual temperature and temperature seasonality) were more influential in cold coniferous and subtropical coniferous forests. Machine learning-based FL models outperform the multiple stepwise regression model in both fitting ability and prediction accuracy. The XGBoost model performed best for cold coniferous, cold broadleaf, subtropical broadleaf, and subtropical mixed forests, with coefficient of determination (R2) values of 0.79, 0.85, 0.81, and 0.83, respectively. The Stacking model excelled in subtropical coniferous forests, achieving an R2 value of 0.82. (4) Conclusions: This study establishes a theoretical foundation for predicting forest fuel capacity in Sichuan Province. It is recommended that the XGBoost model be applied to predict fuel loads (FLs) in cold coniferous forests, cold broadleaf forests, subtropical broadleaf forests, and subtropical mixed forests, while the Stacking model is suggested for predicting FLs in subtropical coniferous forests. Furthermore, this research offers theoretical support for forest fuel management, forest fire risk assessment, and forest fire prevention and control in Sichuan Province.
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PATSYUK, MARINA. "Diversity of Naked Amoebae in Soils of Forest Areas of Zhytomyr Region (Ukraine)." Zootaxa 4743, no. 2 (2020): 257–65. http://dx.doi.org/10.11646/zootaxa.4743.2.8.
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Here we consider the morphotypes and changing species composition of naked amoebae in soils of forest areas in Zhytomyr region (Ukraine). The species composition and morphotypes of amoebae are influenced by the microclimate of soil and litter. Complexes of naked amoebae in the study area constitute two clusters: one of broadleaf (oak) and mixed forests, another of coniferous forests. The most similar species compositions were found in soils of oak and mixed forests (64 % similarity). The least similar were amoebae complexes of coniferous forests and oak forests, and coniferous forests and mixed forests. Non-parametric multidimensional scaling (MDS) showed that species complex of amoebae of mixed forests and oak forests had moister and more acidic soils compared to coniferous forests.
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Alt, Mio, David B. McWethy, Rick Everett, and Cathy Whitlock. "Millennial scale climate-fire-vegetation interactions in a mid-elevation mixed coniferous forest, Mission Range, northwestern Montana, USA." Quaternary Research 90, no. 1 (2018): 66–82. http://dx.doi.org/10.1017/qua.2018.25.
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AbstractMixed coniferous forests are widespread at middle elevations in the Northern Rocky Mountains, yet relatively little is known about their long-term vegetation and fire history. Pollen and charcoal records from Twin Lakes, in the Mission Range of northwestern Montana provide information on mixed-coniferous forest development and fire activity over the last 15,000 years. These data suggest an open parkland and minimal fire activity before 13,500 cal yr BP, consistent with cold, dry conditions. Increases inPinuspollen after 13,500 cal yr BP indicate a transition to closed forests, and a slight rise in fire activity as conditions warmed and fuel biomass increased. High levels ofArtemisiapollen between 10,000 and 6000 cal yr BP suggest an open forest during the early Holocene when conditions were warmer and drier than present. Low-severity fires likely maintained open forest/shrublands but produced little charcoal during this interval. Present-day mixed-coniferous forests were established in the last 6 ka and included forest taxa characteristic of low- (Pseudotsuga-Larix/Pinus ponderosa)and high-severity fire regimes (Picea/Abies). Increased climate variability and anthropogenic burning may have helped maintain heterogeneous, mixed-coniferous forests during the last several millennia when climate conditions became cooler and wetter.
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Klepacki, Adam. "The relationship between height and crown characteristics of four-year-old common birch (Betula pendula Roth)." Forest Research Papers 78, no. 2 (2017): 171–78. http://dx.doi.org/10.1515/frp-2017-0019.
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Abstract This paper presents the results of an analysis on characteristics of birch crowns (Betula pendula Roth) in relation to measures of the growth space occupied by a single tree at a young age. It also presents the relationships between the seedling height and certain crown characteristics. The study focused on four-year-old common birches growing in four different areas in the Elk Forest District in either fresh mixed coniferous or broadleaved forest. The measurements conducted on the chosen trees were used to calculate their crown characteristics such as crown diameter, length, height to the crown base, relative length and spread. They were also used to determine the growth characteristics of a single tree’s growth space, such as the crown area projected onto the ground, single tree space and the percentage use of unit area. Furthermore, fresh and dry leaf mass was determined. The birches growing in the fresh mixed coniferous forest reached an average height of 1.30 m, whereas in the fresh mixed broadleaved forest, the height of the trees was lower and amounted to 0.67 m. 95% of the trees had crown diameters of 0.57 m to 0.74 m in the fresh mixed coniferous forest, but only 0.19 m to 0.25 m in the fresh mixed broadleaved forest. The average lengths of the crowns in the fresh mixed coniferous and broadleaved forests amounted to 0.97 m and 0.37 m respectively. The author shows that there is a statistically significant correlation between the seedling height and the other examined characteristics. The best correlation was found between the height and the length of the crown (r = 0.9858) for birches growing in the fresh mixed coniferous forest and between the height and single tree space (r = 0.8468) for birches growing in the fresh mixed broadleaved forest.
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Adam, Klepacki. "The relationship between height and crown characteristics of four-year-old common birch (Betula pendula Roth)." Lesne Prace Badawcze / Forest Research Papers 78, no. 2 (2017): 171–78. https://doi.org/10.1515/frp-2017-0019.
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This paper presents the results of an analysis on characteristics of birch crowns (<em>Betula pendula</em> Roth) in relation to measures of the growth space occupied by a single tree at a young age. It also presents the relationships between the seedling height and certain crown characteristics. The study focused on four-year-old common birches growing in four different areas in the Elk Forest District in either fresh mixed coniferous or broadleaved forest. The measurements conducted on the chosen trees were used to calculate their crown characteristics such as crown diameter, length, height to the crown base, relative length and spread. They were also used to determine the growth characteristics of a single tree’s growth space, such as the crown area projected onto the ground, single tree space and the percentage use of unit area. Furthermore, fresh and dry leaf mass was determined. The birches growing in the fresh mixed coniferous forest reached an average height of 1.30 m, whereas in the fresh mixed broadleaved forest, the height of the trees was lower and amounted to 0.67 m. 95% of the trees had crown diameters of 0.57 m to 0.74 m in the fresh mixed coniferous forest, but only 0.19 m to 0.25 m in the fresh mixed broadleaved forest. The average lengths of the crowns in the fresh mixed coniferous and broadleaved forests amounted to 0.97 m and 0.37 m respectively. The author shows that there is a statistically significant correlation between the seedling height and the other examined characteristics. The best correlation was found between the height and the length of the crown (r = 0.9858) for birches growing in the fresh mixed coniferous forest and between the height and single tree space (r = 0.8468) for birches growing in the fresh mixed broadleaved forest.
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Wang, Donglin, Qian Wang, Weining Du, et al. "Broad-leaved forest’s impact on spontaneous activities of mice and their mental state." BioResources 19, no. 1 (2024): 1465–78. http://dx.doi.org/10.15376/biores.19.1.1465-1478.
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Empirical studies on the effects of urban forests on the health of humans and other animals are needed to rationalize the construction of urban forests for healthcare. The effects of urban forests (coniferous, broad-leaved, and mixed coniferous and broad-leaved) were studied relative to the physical and mental health of mice and the major environmental factors influencing them. Compared with the control group, the total movement distance of the mice that stayed in the coniferous forest, mixed coniferous and broad-leaved forest, and broad-leaved forest increased 9.7% to 18.1%, the central grid movement distance increased 7.2% to 23.9%, central grid dwell time increased 10.7% to 16.3%, and the number of entries increased 5.2% to 18.6%, indicating that the mental state and the exploration and cognitive abilities of mice were significantly improved in the three urban forests. The broad-leaved forest had greater positive effects than the other two forest types. This can be attributed to a decrease in temperature and the increases in humidity and concentrations of oxygen and negative ions in the air in the broad-leaved forest. The research results provide a theoretical basis for building urban forests that are beneficial to the health of urban residents.
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Huang, Tianbao, Guanglong Ou, Yong Wu, et al. "Estimating the Aboveground Biomass of Various Forest Types with High Heterogeneity at the Provincial Scale Based on Multi-Source Data." Remote Sensing 15, no. 14 (2023): 3550. http://dx.doi.org/10.3390/rs15143550.
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It is important to improve the accuracy of models estimating aboveground biomass (AGB) in large areas with complex geography and high forest heterogeneity. In this study, k-nearest neighbors (k-NN), gradient boosting machine (GBM), random forest (RF), quantile random forest (QRF), regularized random forest (RRF), and Bayesian regularization neural network (BRNN) machine learning algorithms were constructed to estimate the AGB of four forest types based on environmental factors and the variables selected by the Boruta algorithm in Yunnan Province and using integrated Landsat 8 OLI and Sentinel 2A images. The results showed that (1) DEM was the most important variable for estimating the AGB of coniferous forests, evergreen broadleaved forests, deciduous broadleaved forests, and mixed forests; while the vegetation index was the most important variable for estimating deciduous broadleaved forests, the climatic factors had a higher variable importance for estimating coniferous and mixed forests, and texture features and vegetation index had a higher variable importance for estimating evergreen broadleaved forests. (2) In terms of specific model performance for the four forest types, RRF was the best model both in estimating the AGB of coniferous forests and mixed forests; the R2 and RMSE for coniferous forests were 0.63 and 43.23 Mg ha−1, respectively, and the R2 and RMSE for mixed forests were 0.56 and 47.79 Mg ha−1, respectively. BRNN performed the best in estimating the AGB of evergreen broadleaved forests; the R2 was 0.53 and the RMSE was 68.16 Mg ha−1. QRF was the best in estimating the AGB of deciduous broadleaved forests, with R2 of 0.43 and RMSE of 45.09 Mg ha−1. (3) RRF was the best model for the four forest types according to the mean values, with R2 and RMSE of 0.503 and 52.335 Mg ha−1, respectively. In conclusion, different variables and suitable models should be considered when estimating the AGB of different forest types. This study could provide a reference for the estimation of forest AGB based on remote sensing in complex terrain areas with a high degree of forest heterogeneity.
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Egorova, Natalya Yurievna, Venera Nuritdinivna Suleimanova, and Tatiana Leonidovna Egoshina. "Vegetation cover of the river Vyatka flood plain protected areas." Samara Journal of Science 7, no. 2 (2018): 31–36. http://dx.doi.org/10.17816/snv201872105.
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The paper presents results of 4 protected areas investigation within the river Vyatka flood plain. We have conducted a floristic research in accordance with a hierarchy system of floristic complexes by a type-class-group principle, and classified vegetation. 3 types of floristic complexes (forest, meadow, and water), 2 classes (hilltop-flood plain, ridge and natural) and 8 groups of floristic complexes were defined. Small-leaved forest floristic complexes is presented by the following forest types: mixed-herbs-Aegopodium aspen forest, mixed-herbs aspen forest, herbaceous boggy birch forest, cowberry birch forest, aspen-linden birch forest, bilberry-herbaceous birch forest, and mixed-herbs-Filipendula alder forest. Dark coniferous floristic complexes are presented by bilberry spruce and herbaceous spruce forests. Light coniferous forest floristic complexes are: cowberry-herbaceous pine, green-moss-cowberry pine, and stone-bramble-herbaceous pine forests. Broad-leaved forest floristic complexes are presented by flood-plain oak and aspen-linden herbaceous forests. Oak ( Quercus robur L.) is also marked as an undergrowth component of deciduous and coniferous phytocoenoses. Flood-plain meadow floristic complex is formed by gramineous-mixed-herbs and Filipendula-Calamagrostis-mixed-herbs associations. Former river-bed floristic complex is marked within all studied objects. Communities with high level of biodiversity are restricted to water and hilltop-flood-plain ecotopes. Species richness of studied communities varies within 15 to 43 species. Less diverse ecotypes are ridge types. Investigated floristic complexes are habitats of rare and relict species of Kirov Region flora. The study of partial flora composition is a base for vegetation monitoring.
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Tang, Cindy Q., Li-Qin Shen, Peng-Bin Han, et al. "Forest characteristics, population structure and growth trends of Pinus yunnanensis in Tianchi National Nature Reserve of Yunnan, southwestern China." Vegetation Classification and Survey 1 (May 4, 2020): 7–20. http://dx.doi.org/10.3897/vcs/2020/37980.
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Aims: Pinus yunnanesis is commercially, culturally and economically important, but there is a lack of ecological data on its role in stand dynamics. Our aims are to clarify the structure, composition, regeneration and growth trends of primary mature P. yunnanensis forests. Study area: The Tianchi National Nature Reserve in the Xuepan Mountains, Yunlong County, northwestern Yunnan, China. Methods: We investigated forests containing P. yunnanensis, measured tree ages and analyzed the data. Results: Six forest types were identified: (1) coniferous forest: Pinus yunnanensis (Type 1); (2) mixed coniferous and evergreen broad-leaved forest: P. yunnanensis-Lithocarpus variolosus (Type 2); (3) mixed coniferous and deciduous broad-leaved forest: P. yunnanensis-Quercus griffithii (Type 3); (4) mixed evergreen broad-leaved and coniferous forest: Castanopsis orthacantha-P. yunnanensis-Schima argentea (Type 4); (5) mixed coniferous, evergreen and deciduous broad-leaved forest: Pinus yunnanensis-Schima argentea-Quercus griffithii (Type 5); (6) mixed coniferous and evergreen broad-leaved forest: Pinus armandii-Quercus rehderiana-Pinus yunnanensis (Type 6). The size- and age-structure and regeneration patterns of P. yunnanensis were highly variable within these six forest types. P. yunnanensis regeneration was well balanced in forest Type 1 as compared to the other five types. All six forest types were identified as rare and old-growth with P. yunnaensis trees reaching ages of more than 105 years (a maximum age of 165 years with a diameter 116 cm at breast height) except for the Type 4 forest (a 90-year-old stand). Growth rates of P. yunnanensis, based upon ring width measurements, were high for the first 10 years, then declined after the 10th year. In contrast, basal area increment (BAI) increased for the first 25 years, plateaued, and only declined as trees became older. Trees in the older age classes grew more quickly than younger trees at the same age, a consequence of either site quality or competitive differences. The BAI of P. yunnanensis in all age classes in the Tianchi National Nature Reserve was much higher than those of the secondary and degraded natural P. yunnanensis forests of other areas. Conclusions: The P. yunnanensis forests of the Tianchi area appear to be some of the last remnants of primeval and old-growth forests of this species. These forests are structurally diverse and contain a rich diversity of overstory, mid-story, and understory species. Taxonomic reference: Editorial Committee of Flora Republicae Popularis Sinicae (1959–2004) for vascular plants. Abbreviations: BA = basal area; BAI = basal area increment; DBH = diameter at breast height; H = height; RBA = relative basal area.
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Tang, Cindy Q., Li-Qin Shen, Peng-Bin Han, et al. "Forest characteristics, population structure and growth trends of Pinus yunnanensis in Tianchi National Nature Reserve of Yunnan, southwestern China." Vegetation Classification and Survey 1, no. () (2020): 7–20. https://doi.org/10.3897/VCS/2020/37980.
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Aims: Pinus yunnanesis is commercially, culturally and economically important, but there is a lack of ecological data on its role in stand dynamics. Our aims are to clarify the structure, composition, regeneration and growth trends of primary mature P. yunnanensis forests. Study area: The Tianchi National Nature Reserve in the Xuepan Mountains, Yunlong County, northwestern Yunnan, China. Methods: We investigated forests containing P. yunnanensis, measured tree ages and analyzed the data. Results: Six forest types were identified: (1) coniferous forest: Pinus yunnanensis (Type 1); (2) mixed coniferous and evergreen broad-leaved forest: P. yunnanensis-Lithocarpus variolosus (Type 2); (3) mixed coniferous and deciduous broad-leaved forest: P. yunnanensis-Quercus griffithii (Type 3); (4) mixed evergreen broad-leaved and coniferous forest: Castanopsis orthacantha-P. yunnanensis-Schima argentea (Type 4); (5) mixed coniferous, evergreen and deciduous broad-leaved forest: Pinus yunnanensis-Schima argentea-Quercus griffithii (Type 5); (6) mixed coniferous and evergreen broad-leaved forest: Pinus armandii-Quercus rehderiana-Pinus yunnanensis (Type 6). The size- and age-structure and regeneration patterns of P. yunnanensis were highly variable within these six forest types. P. yunnanensis regeneration was well balanced in forest Type 1 as compared to the other five types. All six forest types were identified as rare and old-growth with P. yunnaensis trees reaching ages of more than 105 years (a maximum age of 165 years with a diameter 116 cm at breast height) except for the Type 4 forest (a 90-year-old stand). Growth rates of P. yunnanensis, based upon ring width measurements, were high for the first 10 years, then declined after the 10th year. In contrast, basal area increment (BAI) increased for the first 25 years, plateaued, and only declined as trees became older. Trees in the older age classes grew more quickly than younger trees at the same age, a consequence of either site quality or competitive differences. The BAI of P. yunnanensis in all age classes in the Tianchi National Nature Reserve was much higher than those of the secondary and degraded natural P. yunnanensis forests of other areas. Conclusions: The P. yunnanensis forests of the Tianchi area appear to be some of the last remnants of primeval and old-growth forests of this species. These forests are structurally diverse and contain a rich diversity of overstory, mid-story, and understory species. Taxonomic reference: Editorial Committee of Flora Republicae Popularis Sinicae (1959–2004) for vascular plants. Abbreviations: BA = basal area; BAI = basal area increment; DBH = diameter at breast height; H = height; RBA = relative basal area.
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Shevchenko, N. E., and A. P. Geraskina. "Species and Structural Diversity of Coniferous-Broadleaved Mixed Forests of the Pshekha River, North-Western Caucasus." Лесоведение, no. 6 (November 1, 2023): 637–54. http://dx.doi.org/10.31857/s0024114823060086.
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The article presents the species and structural diversity of coniferous-broadleaved forests of the Pshekha river – the largest tributary of the Kuban river. All in all, 7 main types of forest were identified and described: fir-beech fern-forb forest, fir-hornbeam blackberry-forb forest, aspen-hornbeam honeysuckle-small-herb forest, hornbeam-black alder nitrophilic-tall-herb forest, hornbeam-oak rhododendron-blackberry forest, hornbeam-beech blackberry-forb forest and hornbeam honeysuckle-blackberry forest. The composition of the forest flora of the Pshekha river includes 270 species, including 221 species of vascular plants and 49 species of mosses. Floristic diversity of coniferous-broadleaved forests of the Pshekha river is inversely related to the crown density of the stand and the proportion of oriental beech (Fagus orientalis). The highest species saturation was noted in the hornbeam-black alder nitrophilic-high-grass forest type, the lowest – in the fir-beech fern-forb type. Ecological and coenotic structure of coniferous-broadleaved forest types of the Pshekha river depends on the height above sea level, which determines the indicators of the average annual precipitation and average annual temperature – with a decrease in altitude above sea level. m. the proportion of boreal species in the composition of the flora decreases, while the proportion of nemoral and meadow-edge species increases. In the coniferous-broadleaved forests of the river. Pshekha, 11 species of earthworms were identified, belonging to four morpho-ecological groups: epigeic, epi-endogeic and endogeic, as well as anecic. In forests with a high quality of litter (hornbeam-dominated), the greatest contribution to the biomass is made by epigeic (up to 41%) and endogeic (up to 45%) groups of earthworms. In forests with low quality litter (fir- and beech-dominated), the share of endogeic earthworms is high (up to 66%). Anecic worms are mostly confined to forests on moist soils. In all types of forests, Crimean-Caucasian endemics make a large contribution to biomass and abundance: polymorphic species D. schmidti, anecic D. mariupolienis, as well as Mediterranean species: litter D. attemsi (often inhabiting oak and hornbeam deadwood) and proper soil A. jassyensis. Cosmopolitan species (D. r. tenuis, D. octaedra) are numerous among the epigeic worms and often inhabit deadwood of coniferous tree species.
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Juhász, Orsolya, Ágnes Fürjes-Mikó, Anna Tenyér, et al. "Consequences of Climate Change-Induced Habitat Conversions on Red Wood Ants in a Central European Mountain: A Case Study." Animals 10, no. 9 (2020): 1677. http://dx.doi.org/10.3390/ani10091677.
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The consequences of anthropogenic climate change are one of the major concerns of conservation biology. A cascade of negative effects is expected to affect various ecosystems, one of which is Central European coniferous forests and their unique biota. These coniferous forests are the primary habitat of many forest specialist species such as red wood ants. Climate change-induced rising of temperature allows trees to skip winter hibernation, making them more vulnerable to storms that cause wind felling, and in turn, promotes bark beetle infestations that results in unscheduled clear-cuttings. Red wood ants can also be exposed to such habitat changes. We investigated the effects of bark beetle-induced clear-cutting and the absence of coniferous trees on colonies of Formica polyctena, including a mixed-coniferous forest as a reference. Our aim was to investigate how these habitat features affect the nest characteristics and nesting habits of F. polyctena. Our results indicate that, in the absence of conifers, F. polyctena tend to use different alternatives for nest material, colony structure, and food sources. However, the vitality of F. polyctena colonies significantly decreased (smaller nest mound volumes). Our study highlights the ecological flexibility of this forest specialist and its potential to survive under extreme conditions.
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Liu, Qiaohui, Xiaoping Wang, Jinglan Liu, et al. "The Relationship between the Restorative Perception of the Environment and the Physiological and Psychological Effects of Different Types of Forests on University Students." International Journal of Environmental Research and Public Health 18, no. 22 (2021): 12224. http://dx.doi.org/10.3390/ijerph182212224.
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Short-term exposure to a forest environment is beneficial to human physiological and psychological health. However, there is little known about the relationship between the restorative perception of environment and physiological and psychological restoration achieved by experiencing the forest environment. This study evaluated the relationship between the restorative perception of different types of forests and human physiological and psychological effects. A sample of 30 young adult students from Beijing Forestry University was exposed to coniferous, deciduous, and mixed forests as well as an urban site. Restorative perception of the environment was measured using the PRS questionnaire. Restorative effects were measured using physiological indicators (blood pressure and heart rate) and three psychological questionnaires (Restorative Outcome Scale; Subjective Vitality Scale; Warwick–Edinburgh Mental Well-being Scale). The results demonstrated the following: (1) There were significant differences in the perceived restorative power of the three types of forests, with the highest level in the mixed forest, followed by the coniferous forest and the deciduous forest. (2) All types of forests were beneficial to physiological and psychological restoration. The mixed forest had the greatest effect in lowering blood pressure and heart rate as well as increasing vitality, while the coniferous forest had the strongest increases in psychological restoration and positive mental health. (3) The level of perceived restorative power of environment was positively related to the physiological and psychological restoration. These findings provide practical evidence for forest therapy that can maximize the restorative potential of forests.
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Zhao, Junfang, Jinlong Ai, Yujie Zhu, Ruixi Huang, Huiwen Peng, and Hongfei Xie. "Carbon budget of different forests in China estimated by an individual-based model and remote sensing." PLOS ONE 18, no. 10 (2023): e0285790. http://dx.doi.org/10.1371/journal.pone.0285790.
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Forests play a key role in the regional or global carbon cycle. Determining the forest carbon budget is of great significance for estimating regional carbon budgets and formulating forest management policies to cope with climate change. However, the carbon budget of Chinese different forests and their relative contributions are not completely clear so far. We evaluated the carbon budget of different forests from 1981 to 2020 in China through combining model with remote sensing observation. In addition, we also determined the relative contribution of carbon budget of each forest type to all forests in China. Eight forest types were studied: evergreen coniferous forest (ECF), deciduous coniferous forest (DCF), coniferous and broad-leaved mixed forest (CBF), deciduous broad-leaved forest (DBF), evergreen broad-leaved forest (EBF), evergreen deciduous broad-leaved mixed forest (EDBF), seasonal rain forest (SRF), and rain forest (RF). The results indicated that the Chinese forests were mainly carbon sink from 1981 to 2020, particularly the annual average carbon budget of forest from 2011 to 2020 was 0.191 PgC·a-1. Spatially, the forests’ carbon budget demonstrated obvious regional differences, gradually decreasing from Southeast China to Northwest China. The relative contributions of carbon budget in different forests to all forests in China were different. During 2011–2020, the ECF forests contributed the most carbon budget (34.45%), followed by DBF forests (25.89%), EBF forests (24.82%), EDBF forests (13.10%), RF forests (2.23%), SRF forests (3.14%) and CBF forests (1.14%). However, the DCF forests were found mainly as carbon source. These results contribute to our understanding of regional carbon budget of forests.
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Wang, Gang, Binglou Xie, Yulong Lv, et al. "Interaction Effect of Stand Age and Diversity on Aboveground Wood Carbon Accumulation in Subtropical Mixed Forests of the Zhejiang Province (China)." Forests 14, no. 2 (2023): 262. http://dx.doi.org/10.3390/f14020262.
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Aboveground wood carbon (AWC) stocks in forest ecosystems are mediated by biotic and abiotic variables. Understanding the internal regulatory mechanisms of forests is important for future forest management and global climate change mitigation. However, how these factors affect AWC in subtropical mixed forests remains poorly understood. Using a database from the National Forest Inventory (NFI) from China, we observed the effects of climate variables (temperature and precipitation), stand structure indices (stand density and DBH coefficient of variation and diversity), stand diversity indices (taxonomic diversity, functional diversity, and phylogenetic diversity), and stand functional indices on coniferous mixed forests (CMF), coniferous–broadleaf mixed forests (CBMF), and broadleaf mixed forests (BMF). Meanwhile, we examined the AWC based on a linear mixed model and a structural equation model for each mixed forest. We found that both stand structure and stand diversity can affect the AWC through their indirect effects on the stand function, aligning with the niche complementarity effect. Stand age is an important factor affecting AWC because it interacts with stand structure and stand diversity. Our study highlights that AWC is dependent on the regulation of stand age and structure, which can be crucial for boosting high carbon stocks in subtropical forests.
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Zhu, Shuxin, Jiyue Li, Qian He, et al. "Temporal Dynamics and Influencing Mechanism of Air Oxygen Content in Different Vegetation Types." Forests 15, no. 3 (2024): 432. http://dx.doi.org/10.3390/f15030432.
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Air oxygen content, an essential index for measuring air quality, is affected by vegetation and the environment in the forest. However, the scientific understanding of the influential mechanism of air oxygen content in different vegetation types is still not clear. Focusing on four different vegetation types: broad-leaved forest, coniferous forest, coniferous and broad-leaved mixed forest, and non-forest land within Shimen National Forest Park, China, the temporal dynamics of air oxygen content and its relationship with four environmental factors (temperature, relative humidity, wind speed, and negative air ion concentration) in different vegetation types were explored based on path analysis and decision analysis. The results showed that there was a noteworthy impact of vegetation types on air oxygen content, with coniferous and broad-leaved mixed forest (21.33 ± 0.42%) presenting the highest levels. The air oxygen content indicated a fundamentally consistent temporal pattern across different vegetation types, with the highest diurnal variation occurring at noon. It reached its peak in August and hit its nadir in December, with summer > spring > autumn > winter. In broad-leaved forest, the air oxygen content was determined by temperature, wind speed, negative air ion concentration, and relative humidity; in both coniferous forest and coniferous and broad-leaved mixed forest, the air oxygen content was affected by temperature, wind speed, and relative humidity; in non-forest land, the air oxygen content was influenced by temperature and wind speed. Generally, temperature was the dominant factor affecting air oxygen content in different vegetation types, and its positive impact tremendously exceeded other environmental factors. Wind speed had a positive impact on air oxygen content in three forest communities but a negative effect on non-forest land. Relative humidity acted as a limiting factor for air oxygen content within three forest communities. Negative air ion concentration showed a significant positive correlation on air oxygen content in broad-leaved forest. Therefore, when planning urban forests to improve air quality and construct forest oxygen bars, it is recommended that the tree species composition should be given priority to the coniferous and broad-leaved mixed pattern. Meanwhile, make sure the understory space is properly laid out so that the forest microclimates are conducive to the release of oxygen by plants through photosynthesis.
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AKSOY, Hasan. "AHP ile Taşkın Risk Analizi ve Doğal Taşkın Yönetiminde Ormanların Rolü: Türkiye'nin Kuzeyinden Bir Vaka Çalışması." Kastamonu University Journal of Forestry Faculty 23, no. 3 (2023): 282–97. http://dx.doi.org/10.17475/kastorman.1394958.
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Aim of studty: The aim of this study is to determine the flood risk map of the study area where floods and flood events are frequently encountered by AHP method.
 Study area: The study was carried out within the boundaries of the Sinop Regional Directorate of Forestry, Ayancık Forest Management Directorate.
 Material and method: The flood risk map of the study area was produced by Analytical Hierarchy Process (AHP) method. For AHP, 6 different criteria were used: slope, precipitations, aspect, stream distance, land use, and soil. Forest type maps of the study area were used to analyze the impact of forests on flood risk. In terms of forest structure, the stand structure was divided into 3 classes as coniferous, broadleaf, and mixed forest. 
 Main results: The results showed that flood risk varies with forest structure. Coniferous forest class was determined as the class with the lowest flood risk and mixed forest as the class with the highest flood risk.
 Research highlights: It was determined that the flood risk changed according to the forest structure. Coniferous forest class was determined as the class with the least flood risk, and mixed forest was determined as the class with the highest flood risk.
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Meng, Zhuonan, Ying Yu, Xiguang Yang, and Tao Yang. "Estimation of Chlorophyll Content at Stand and Individual Tree Level by UAV Hyperspectral Combined with LiDAR." Remote Sensing 17, no. 10 (2025): 1699. https://doi.org/10.3390/rs17101699.
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Chlorophyll plays a significant role in evaluating vegetation health and forest carbon sink. In this study, a total of 36 characteristic variables from hyperspectral image and lidar point cloud data acquired through an unmanned aerial vehicle (UAV) platform were used to evaluate the accuracy of statistical models including multiple stepwise regression, BP neural network, BP neural network optimized by firefly algorithm, random forest, and the mixed data-driven mechanistic model PROSPECT model in estimating chlorophyll content for three different forest types in Maoershan Forest Farm of Northeast Forestry University in Heilongjiang Province, namely coniferous forest, broad-leaved forest, and coniferous–broad-leaved mixed forest. The accuracy of the models was evaluated by the coefficient of determination (R2) and root mean square error (RMSE). The results show that random forest (R2 = 0.59–0.64, RMSE = 3.79–5.83 µg·cm−2) among all statistical models is superior to other models. The accuracy of the mechanism model was the highest (R2 = 0.97, RMSE = 3.40 µg·cm−2). There were significant differences in chlorophyll content among different forest types. It ranged from 25.25 to 31.60 µg·cm−2 for broad-leaved forests, which was higher than that of coniferous and broad-leaved mixed forests (13.52–23.93 µg·cm−2) and coniferous forests (6.40–13.71 µg·cm−2). In the horizontal direction, the chlorophyll content near the center of the canopy was lower than that at the edge of the canopy. In the vertical direction, there was no significant difference in chlorophyll content between different canopies of Pinus sylvestris var. mongolica, while there was a significant difference in chlorophyll content between the upper, middle, and lower canopies of Juglans mandshurica. For different tree species, the variation in chlorophyll with crown height was different.
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Hu, Yichen, Wenzuo Zhou, Baiping Zhang, Dan Li, and Xinyu Yao. "Aboveground Forest Biomass Generally Increases with Elevation Gradients in China’s Qinling–Daba Mountains." Forests 16, no. 5 (2025): 796. https://doi.org/10.3390/f16050796.
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The complexity of forest ecosystems leads to differences in the distribution patterns of different vegetation types along elevation gradients. This study aimed to explore the characteristics of AGB variations along elevation gradients for different forest types and tree species components in the Qinling–Daba Mountains. Based on 329 field vegetation survey plots, including four sampling transects and four representative mountains, individual tree AGB was calculated using allometric biomass equations. Further, generalized additive models (GAMs) were used to investigate the relationships between AGB and elevation for four forest types (broadleaf forests, coniferous forests, mixed coniferousbroadleaf forests, and shrublands) and three AGB components (total AGB (tAGB), broadleaf species AGB (bAGB), and coniferous species AGB (cAGB)) across eight vegetation survey regions. The results showed that the AGB of different forest types is significantly related to elevation (p < 0.05), with broadleaf forest AGB showing a unimodal pattern with elevation, coniferous forest and mixed forest AGB increasing with elevation, and shrubland AGB exhibiting a noticeable rise at higher elevations. The AGB components across different vegetation survey regions also showed significant relationships with elevation (p < 0.05), with broadleaf species AGB displaying a monotonically increasing trend in regions with a small elevation range and exhibiting a unimodal or bimodal distribution in regions with a large elevation range, while coniferous species AGB generally increased with elevation. Although elevation significantly influenced forest AGB, the variation in R2 values indicated that elevation is not the sole determinant of AGB variation. This study improves the understanding of spatial patterns of forest biomass along elevation gradients.
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Jerabkova, Lucie, Cindy E. Prescott, and Barbara E. Kishchuk. "Nitrogen availability in soil and forest floor of contrasting types of boreal mixedwood forests." Canadian Journal of Forest Research 36, no. 1 (2006): 112–22. http://dx.doi.org/10.1139/x05-220.
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Boreal mixedwood forests with varying proportions of coniferous and deciduous species are found throughout the North American continent. Maintenance of a deciduous component within boreal forests is currently favoured, as deciduous species are believed to promote faster nutrient turnover and higher nutrient availability. Results of comparisons of deciduous and coniferous forests are, however, inconsistent in supporting this generalization. We compared indices of soil nitrogen (N) availability in the forest floor and mineral soil of deciduous, mixed, and coniferous stands of boreal mixedwood forest in northwestern Alberta. Deciduous stands had higher N availability, reflected by higher pools of NH4-N and inorganic N in the forest floor. Forest floors of deciduous stands also tended to have higher concentrations of microbial N but did not have higher levels of NO3-N or higher rates of net nitrification. Mixed stands showed the highest rates of net N mineralization. Soil N availability was more closely related to litter N content than to litter decomposition rate. The variation among the forest types is likely attributable to vegetation, as topography is fairly uniform, stands do not differ in soil texture, and N-availability indices correlated directly with the proportion of deciduous trees.
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Wu, Ruoyun, Chen Dong, Chengwei Zhang, Weifang Gao, Xinyu Zheng, and Xiongwei Lou. "Classification Model of Site Quality for Mixed Forests Based on the TWINSPAN Method and Site Form in Southwestern Zhejiang." Forests 15, no. 12 (2024): 2247. https://doi.org/10.3390/f15122247.
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The evaluation of site quality for mixed forests is a comprehensive approach to analyzing forest site conditions and tree species growth performance. Accurate site quality assessment is crucial for understanding and enhancing the ecological functions and productivity potential of forests. This study focuses on mixed forests in Lishui City, Zhejiang Province. Using the Two-way Indicator Species Analysis (TWINSPAN) method, coniferous mixed forest, broadleaved mixed forest, and mixed coniferous–broadleaved forests in the region were classified into 15 forest types. Site form models for each type were then constructed using the Algebraic Difference Approach (ADA) to categorize site quality levels. Subsequently, a site quality classification model was developed by integrating site and climatic factors, employing four machine learning algorithms: Random Forest (RF), K-Nearest Neighbors (KNN), Support Vector Machine (SVM), and XGBoost. This model effectively facilitated the evaluation of site quality in mixed forests. The results showed that, across the 15 forest types, the site form models based on the ADA method achieved R2 values greater than 0.634, indicating accuracy in capturing tree height growth trends in mixed forests. For site quality classification, all four models (RF, KNN, SVM, and XGBoost) achieved overall accuracies above 0.77. Among these, the machine learning models ranked in effectiveness for site quality classification as follows: XGBoost > RF > SVM > KNN. These findings suggest that the site form model is a suitable criterion for classifying site quality in mixed forests in Lishui City, Zhejiang Province, and that the XGBoost-based model demonstrates strong classification accuracy. This study provides a scientific basis for site-adapted tree selection and advances information on mixed forest management.
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Song, Yifan, Ge Yan, and Guangfu Zhang. "Light Competition Contributes to the Death of Masson Pines of Coniferous-Broadleaf Mixed Forests in Subtropical China." Forests 13, no. 1 (2022): 85. http://dx.doi.org/10.3390/f13010085.
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In the process of subtropical forest succession, it has long been recognized that population decline of Masson pines in coniferous-broadleaf mixed forest is caused by shading from broadleaf trees. However, little is known about the mechanism underlying the interaction between them. Here, we first chose two sets of Masson pine plots approximately aged 60 years in subtropical mountainous areas in eastern China (i.e., pure coniferous forest vs. coniferous-broadleaf mixed forest). Then, we measured and compared tree height, diameter at breast height, first branch height (FBH), live crown ratio (LCR) of Masson pines between the two sets of plots, and also determined the difference in growth performance of Masson pines relative to their neighboring broadleaf trees in the mixed forest stand. Compared with plots in pine forests, Masson pines in mixed plots had lower tree height and crown breadth, higher FBH, lower LCR, and leaf area. Furthermore, the difference of mean FBH between reference trees (Masson pines) and their neighboring trees (i.e., broadleaf trees) in mixed forest plots was greater than that in pine forest plots, and the ratio of LCR between Masson pines and their neighbors (0.46) in mixed forest was significantly smaller than in pine forest (1.05), indicating that those broadleaf trees around Masson pines probably affected their growth. The mean distance between Masson pines and neighboring trees (1.59 m) in mixed forest plots was significantly shorter than in pine forest plots (2.77 m) (p < 0.01), suggesting that strong competition may occur between reference trees and their neighbors. There was a significant difference in the ratio of crown volume between reference tree Masson pine and its neighboring trees in mixed forests (p < 0.01), indicating that the ratio of biomass synthesis to consumption of pines was much lower than their nearby broadleaf trees in mixed forest. Our results have demonstrated for the first time that Masson pines’ population decline is affected by shade-tolerant broadleaf late-successional species, which can be primarily attributed to the distinctive light transmittance of dominant species nearby (pure pine vs. mixed forest). This study provides a new perspective for future studies on the mechanism of forest succession.
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Długosiewicz, Justyna, Stanisław Zając, and Emilia Wysocka-Fijorek. "Evaluation of the natural and artificial regeneration of Scots pine Pinus sylvestris L. stands in the Forest District Nowa Dęba." Forest Research Papers 80, no. 2 (2019): 105–16. http://dx.doi.org/10.2478/frp-2019-0009.
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Abstract The main purpose of this article was to highlight the potential for enhancing positive silvicultural effects and their dependency on the management method in Scots pine Pinus sylvestris L. stands. We therefore assessed the impact of natural and artificial regeneration on vitality and health, compaction, surface coverage and seedlings height. Another important goal was to assess the severity of damage in the selected forest sites. A comparative analysis was carried out based on results from field work conducted in the autumn 2010 in the Forest District Nowa Dęba. As part of this field work, also the breeding quality of the analyzed pine renewals was assessed. The obtained results indicate that natural regeneration of Scots pine under the conditions of a fresh coniferous forest as well as a fresh mixed coniferous forest is the most reasonable management practice. In wet mixed coniferous forests however, the naturally regenerating Scots pine seedlings are of lower silvicultural quality and growth parameter values compared to those in artificially regenerated stands. In fresh mixed broadleaved forests, naturally regenerated Scot pine trees showed slightly lower silvicultural quality and vitality than artificially regenerated trees. Our results indicate furthermore that there are indeed conditions under which the restoration of Scots pine in the Nowa Dęba Forest District using natural regeneration is preferable. We also found that the employed method of renewing has a significant impact on pine growth parameters in the moist mixed coniferous forest habitat. Naturally renewing pines are characterized by a lower overall viability, but at the same time natural regeneration provides a larger number of individuals with the best viability (1st vitality class), which can be a valuable selection basis for trees used in breeding.
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Jamroz, Elżbieta, Andrzej Kocowicz, Jakub Bekier, Magdalena Dębicka, and Irmina Ćwieląg-Piasecka. "Response of the Soil Organic Matter to Clear-cutting in the Face of Climate Change – a Report from the East Sudety Mountains, South-West Poland." Acta Horticulturae et Regiotecturae 27, no. 1 (2024): 42–50. http://dx.doi.org/10.2478/ahr-2024-0007.
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Abstract Clear-cutting induces biogeochemical, ecological, and hydrological changes in the soil environment, especially in the conditions of climate change effect. This type of management affects soil carbon sequestration. In this paper, we generalize the effect of clear-cutting in mountainous mixed coniferous forests on the direction of organic matter transformation and the properties of humic substances. Soil samples of dystric Cambisols were taken two and ten years after clear-cutting (CC). Soil profiles located at the same elevation under forest cover without any harvesting were used as references. The contents of total organic carbon, total nitrogen, qualitative and quantitative characteristics of humic substances, as well as the mineralogical composition and the clay-associated C fraction, were analysed. Under mountainous conditions, clear-cutting in the mixed coniferous forest enhanced organic matter decomposition and decreased the low-molecular weight humic fraction. It also caused the accumulation of more stable humic acids, particularly in the upper soil horizons, and resulted in accumulation of humic substances with higher contents of C and O and lower H content in the first years after CC. Clear-cutting in the first two years reduced the aliphacity of humic acids in the topsoil. Ten years after harvesting, a significant increase in aliphacity in the Oa horizon confirmed organic matter recovery. Mixed coniferous forests are more resistant to biotic and abiotic disturbances, which is particularly important in the face of violent weather phenomena related to climate change. Thus, forest management plans should consider the conversion of spruce monocultures to mixed coniferous forests.
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Jia, Shuxia, Xingpeng Li, Wensheng Sun, et al. "Fine Root Traits of Pinus koraiensis Varied with Soil Cation Exchange Capacity in Natural Forests." Land 10, no. 4 (2021): 363. http://dx.doi.org/10.3390/land10040363.
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Adaptation of fine root plasticity to soil nutrients heterogeneity in natural forest ecosystems has not been well explored. The study aimed to determine seasonal variations of fine root traits in Pinus koraiensis natural forests and explore the relationship between fine root traits and soil properties. Root and soil samples were collected from the coniferous broad-leaved mixed forest (BP), monospecific P. koraiensis forest (MP), and coniferous mixed forest (CP). Soil available phosphorus (P) content for MP was 31.7% and 39.8% lower than for BP and CP. Soil cation exchange capacity (CEC) for MP was lower by 23.5% and 27.2% than for BP and CP, respectively. In July, specific root lengths and root surface areas for BP and CP (mixed forests) were significantly higher than for MP (monospecific forest). A structural equation model showed that CEC had a significant effect on fine root traits. Root diameter, root volume density, and root surface area density were negatively correlated with CEC. Fine root traits plasticity of P. koraiensis are closely related to soil available nutrient contents, CEC, and species composition at the ecosystem level.
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Savchenkova, Vera A., Sergey B. Vasilyev, and Vladimir F. Nikitin. "Features of Restoration of Coniferous-Broad-Leaved Forests." Lesnoy Zhurnal (Forestry Journal), no. 6 (December 10, 2024): 133–46. https://doi.org/10.37482/0536-1036-2024-6-133-146.
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The article is devoted to the problem of restoration of cut down forests in the forest area of coniferous-broad-leaved (mixed) forests of the centre of the European part of Russia. Due to the intensive use of forest resources, in order to rationally plan their restoration, there is a need for systematic assessment of the natural and artificial restoration of the main forest-forming species. For areas with a developed network of transport routes, the problem of deterioration of the species composition of forests, as well their qualitative condition as a result of prolonged and intensive forest exploitation is currently increasing. This has determined the purpose of the study, which has been carried out through a field survey of undergrowth and forest planations of forest-forming species according to the methodology by A.V. Pobedinsky and the standard methodology for undergrowth inventory. Young stands of natural (undergrowth) and artificial (created by planting) origin in coniferous-broad-leaved (mixed) forests of the European part of Russia after clear-cutting of trees have become the object of the study. An analysis of the structre of production and demand (according to the survey data) has shown that preference is given to harvesting birch (40 % of the volume cut down). The results of comparing the growth characteristics of the younger generation of tree species, taking into account the age and density of their growth, has allowed us to conclude that the undergrowth adapts easier and faster mainly to the growing conditions B4, B3, C3, C4, A4, A3, and occasionally B2, compared to forest plantations. In many cases, spruce plantations created by planting in the bottom of a furrow are completely destroyed (get soaked) or remain in a volume that does not provide satisfactory reforestation. Cases of exposure of the root system of spruce plantations at the age of 22, which have been created by planting in the dump, have been revealed. Based on experimental data, it has been established that productive young stands of natural origin are successfully formed in the forest area of coniferous-broadleaved (mixed) forests of the Yaroslavl, Moscow and Nizhny Novgorod Regions. Criteria for the inventory of undergrowth and young growth of soft-wooded broad-leaved species have been proposed. Proposals have been developed to improve the efficiency of reforestation measures in forest-growing conditions corresponding to the A4, B4, C4, as well as in the A3, B3 and C3 conditions. The positive effect of raspberries on self-seeding of the main forest-forming species has been noted. The self-sown plants in such areas is 1.0–1.5 thousand pcs/ha.
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Zhao, Chao, Xiaoqiang Li, Xinying Zhou, Keliang Zhao, and Qing Yang. "Holocene Vegetation Succession and Response to Climate Change on the South Bank of the Heilongjiang-Amur River, Mohe County, Northeast China." Advances in Meteorology 2016 (2016): 1–11. http://dx.doi.org/10.1155/2016/2450697.
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Pollen samples from peat sediments on the south bank of the Heilongjiang River in northern Northeast China (NE China) were analyzed to reconstruct the historical response of vegetation to climate change since 7800 cal yr BP. Vegetation was found to have experienced five successions from cold-temperate mixed coniferous and broadleaved forest to forest-steppe, steppe-woodland, steppe, and finally meadow-woodland. From 7800 to 7300 cal yr BP, the study area was warmer than present, andBetula, Larix, andPicea-dominated mixed coniferous and broadleaved forests thrived. Two cooling events at 7300 cal yr BP and 4500 cal yr BP led to a decrease inBetulaand other broadleaved forests, whereas herbs of Poaceae expanded, leading to forest-steppe and then steppe-woodland environments. After 2500 cal yr BP, reduced temperatures and a decrease in evaporation rates are likely to have resulted in permafrost expansion and surface ponding, with meadow and isolated coniferous forests developing a resistance to the cold-wet environment. The Holocene warm period in NE China (7800–7300 cal yr BP) could have resulted in a strengthening of precipitation in northernmost NE China and encouraged the development of broadleaved forests.
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Jetté, Hélène, and Robert J. Mott. "Vegetation and Climate of Maritime Canada 6000 Years BP: A Synthesis." Géographie physique et Quaternaire 49, no. 1 (2007): 141–62. http://dx.doi.org/10.7202/033034ar.
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ABSTRACT Environmental conditions (vegetation and climate) of Maritime Canada are reconstructed as a regional contribution to a national synthesis on the paleoenvironment of Canada 6000 yr BP. Ten new sites, including three complete sequences and seven short sequences bracketing the 6 ka period, are added to the existing pollen dataset for this region. The vegetation prevalent 6000 yr BP in New Brunswick was a mixed coniferous-deciduous forest with pine, mostly white pine (Pinus strobus) in the northwest, and a mixed coniferous-deciduous forest with hemlock (Tsuga canadensis) in the south and southeast. In the northwest, fir (Abies) replaced pine at high elevations and a boreal forest grew on the New Brunswick Highlands. The dominant vegetation at 6000 yr BP in Prince Edward Island and Nova Scotia was a mixed coniferous-deciduous forest with hemlock dominating. Cape Breton Island was covered by a mixed coniferous-deciduous forest with pine and/or fir, except for the southern part of the Island where hemlock was probably present. Analysis of the fossil sites indicate that a warm-dry period influenced the composition of the vegetation 6000 yr BP.
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Liu, Yujia, Bingju Zhao, Yumeng Han, Chunjing Zou, and Chenghuan Wang. "Responses of Sesamum indicum to Allelopathy of Coniferous and Broadleaved Trees." Ecologies 6, no. 1 (2025): 21. https://doi.org/10.3390/ecologies6010021.
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The relationships among species and the mechanics of those relationships are very complicated in mixed forests, and allelopathy is one of the most important mediators of these relationships. The types and quantities of allelopathic chemicals are different in coniferous and broadleaved trees; studying the responses of some sensitive plants, such as certain crops, to allelopathy mediated by the leaf extracts of coniferous and broadleaved trees would be an effective technique to evaluate the relationships among species in a mixed forest. In this paper, the effects of leaf extracts from Metasequoia glyptostroboides, Cedrus deodara, Liquidambar formosana, Platanus acerifolia and a mixture of of coniferous and broadleaved trees on seed germination and seedling growth of Sesamum indicum at a constant concentration (50 gDW/L) were investigated using an indoor filter paper culture dish method. The test results were evaluated using the response index (RI) and the synthesis allelopathic effect index (SE). The results showed that: (1) Four kinds of leaf extracts inhibited the germination and seedling growth of S. indicum. The order of the allelopathic inhibitory effects were as follows: L. formosana > M. glyptostroboides > C. deodara > P. acerifolia; (2) In this experiment, the single leaf extract of the coniferous species (M. glyptostroboides and C. deodara) and the single leaf extract of the broadleaved species (L. formosana and P. acerifolia) did not exhibit significant differences in the direction of the allelopathic effect on S. indicum; (3) Compared to their corresponding single leaf extracts, M. glyptostroboides + P. acerifolia and C. deodara + P. acerifolia mixed leaf extracts promoted the allelopathic effects of S. indicum, namely, the coniferous-broadleaved mixed leaf extract > one single leaf extract > another single leaf extract. The rest of the coniferous-broadleaved mixed leaf extract treatment groups neutralized the allelopathic effects of S. indicum, namely, one single leaf extract > coniferous leaf mixed extract > another single leaf extract. The conclusions could provide a scientific basis for managing forests, especially mixed forest ecosystems.
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Shvetsov, E. G., A. S. Golyukov, and V. I. Kharuk. "Long-Term Dynamics of Forest Fires in Southern Siberia." Contemporary Problems of Ecology 16, no. 2 (2023): 205–16. http://dx.doi.org/10.1134/s1995425523020154.
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Abstract The research focus. Wildfire is a critical environmental disturbance affecting forest dynamics, succession, and the carbon cycle in Siberian forests. Forests of southern Siberia experienced an increase of fire rate. We analyzed spatial and temporal dynamics of burned area in the southern Central Siberian Mountains. We considered burning rate within different forest types: dark needle conifers (DNC) composed by Siberian pine, spruce and fir, light-needle composed by Scotch pine and larch, and mix wood (composed by birch, aspen and conifers). Methods. We used long-term (1982–2021) climatic variables from the ERA5-Land database. Satellite observations included MODIS wildfire data (2002–2021) and gravimetric (GRACE) data (2002–2021) for estimation soil moisture content. We analyzed the spatial distribution of burned areas considering dominant forest stands and terrain (elevation, slope aspect and steepness). Results. We found a significant decreasing trend in burned area. On average, about 978.7 ± 447.5 thousand ha including 257.1 ± 154.3 thousand ha of forests are disturbed by fire annually. Light coniferous forests are characterized by the highest degree of the fire disturbance (relative burned area, RBA, was ca. 0.83% per year); whereas DNC stands have the lowest RBA (ca. 0.15% per year). The spatial distribution of fires in light coniferous forests showed predominance of fires on the southern slopes comparing to northern slopes (by 15–20%). We found a decreasing logarithmic trend in burned area between plains and low mountains and high mountains due to lower forest fuel loads and increased amount of precipitation on higher elevations. We also observed lower RBA values (by 300–400%) on steep slopes for light coniferous forests and mixed forests comparing to gentle slopes due to lower available forest fuels. The long-term dynamics of burned area in the region was related to the variation of climatic variables, such as soil moisture (r2 = 0.70, p < 0.01), moisture content (r2 = 0.63, p < 0.01) and drought index (r2 = 0.3, p < 0.05).
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Strukelj, Manuella, Suzanne Brais, Sylvie A. Quideau, et al. "Chemical transformations in downed logs and snags of mixed boreal species during decomposition." Canadian Journal of Forest Research 43, no. 9 (2013): 785–98. http://dx.doi.org/10.1139/cjfr-2013-0086.
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Snags and downed logs are substantial components of the detrital carbon pool in boreal forests. Effects of their decomposition on chemical and physical characteristics of the forest floor remain relatively unknown. The main objective of this study was to characterize chemical transformations of decaying logs and snags of common tree species in the boreal mixedwood forest. Logs and snags from a wide range of decay classes were sampled and analyzed by solid-state 13C nuclear magnetic resonance spectroscopy and by near-infrared spectroscopy. Little or moderate chemical changes appeared in fresh and moderately decayed snags and logs, but in well-decayed logs, substantial degradation of carbohydrates and increases in lignin concentrations occurred. Deciduous species had initially more carbohydrates than coniferous species, but decomposition narrowed their differences, and in well-decayed logs, species differed mainly in terms of their lignin concentrations. Well-decayed deciduous logs reached very low wood densities, and their integration into the forest floor and long-term preservation remains questionable. In contrast, chemical composition of well-decayed coniferous logs resembles that of lignic forest floor (i.e., forest floor originating from deadwood decomposition), with preserved lignins, carbohydrates, and alkyl carbon compounds. Decomposed coniferous wood thus contributes to chemical heterogeneity of the forest floor, possibly promoting diversity of decomposers as well as carbon retention in soils.
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Peng, Lingli, Saixin Cao, Yilin Chen, et al. "The Restorative Effect of Urban Forest Vegetation Types and Slope Positions on Human Physical and Mental Health." Forests 16, no. 4 (2025): 653. https://doi.org/10.3390/f16040653.
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The restorative effects of various environmental factors within urban forests on physical and mental health exhibit significant differences. Specifically, vegetation types and topographical slope positions are key elements contributing to the environmental heterogeneity of urban forests. However, there is a lack of studies that have concurrently examined the health restoration effects of both factors. This study conducted an empirical experiment on university students in urban forests during the autumn season, investigating the effects of different vegetation types and slope positions on physiological and psychological restoration, and identifying the key environmental factors contributing to these effects. The results show the following: (1) Urban forests with different vegetation types exhibit varying restorative effects, with coniferous forests offering greater physiological restoration benefits than coniferous–broadleaf mixed forests. (2) Slope position affects both physiological and psychological restoration. In coniferous forests, the restorative effects on physical and mental health are greater at the top and midslope positions compared to the bottom slope position; in coniferous–broadleaf mixed forests, the best physiological restoration effects occur at the midslope position. (3) The key environmental factors influencing physiological restoration in urban coniferous forests are panoramic green coverage and elevation. (4) In urban coniferous–broadleaf mixed forests, temperature, humidity, and wind speed are the key factors affecting physiological restoration. This study reveals the restorative differences in urban forests under different vegetation types and slope positions, identifies the key environmental factors influencing health restoration, and provides a theoretical basis for further research on the impact of urban forests on human health. Future urban forest layout and design should fully consider the characteristics of different slope positions, optimize microclimate regulation, and maximize their role in promoting public health.
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Zhang, Li, Yulian Yang, Zebin Jiao, et al. "Response of Soil Net Nitrogen Mineralization to a Litter in Three Subalpine Forests." Forests 13, no. 4 (2022): 597. http://dx.doi.org/10.3390/f13040597.
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Forest litter accumulation can regulate the soil microclimate and alter nutrient distribution, but the effects of litter quality and seasonal differences on soil nitrogen (N) mineralization are still uncertain. The effects of litter change on the rates of net N mineralization, nitrification, and ammonification were studied through in situ incubation experiments in coniferous, mixed, and broad-leaved forests in the eastern Qinghai–Tibetan Plateau. Two litter treatments were established, one to allow the litter to enter the soil normally (remain litter) and the other to prevent the litter from entering the soil (remove litter). Soil samples were collected at the freezing (FS), thawing (TS), early growing (EGS), late growing (LGS), and early freezing (EFS) seasons during the 1.5-year incubation period. Compared to coniferous forests, the effects of litter removal on the net ammonification, nitrification, and N mineralization rates were more pronounced in broad-leaved forests, mainly during the growing and thawing seasons. Structural equation modeling indicated that microbial biomass N (MBN) was a common factor affecting the net ammonification, nitrification, and N mineralization rates in the three forest soils. The coniferous forest microbial biomass carbon (MBC), mixed forest soil moisture, broad-leaved forest soil N concentration, and C:N ratio were the unique influencing factors of the different forest types. The results showed that the effect of litter distribution on the soil net N mineralization mainly depended on forest type and season, suggesting that the litter composition and productivity in different seasons and forest types may alter the soil N cycling processes in subalpine forest ecosystems.
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Justyna, Długosiewicz, Zając Stanisław, and Wysocka-Fijorek Emilia. "Evaluation of the natural and artificial regeneration of Scots pine Pinus sylvestris L. stands in the Forest District Nowa Dęba*." Lesne Prace Badawcze / Forest Research Papers 80, no. 2 (2019): 105–16. https://doi.org/10.2478/frp-2019-0009.
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The main purpose of this article was to highlight the potential for enhancing positive silvicultural effects and their dependency on the management method in Scots pine <em>Pinus sylvestris</em> L. stands. We therefore assessed the impact of natural and artificial regeneration on vitality and health, compaction, surface coverage and seedlings height. Another important goal was to assess the severity of damage in the selected forest sites. A comparative analysis was carried out based on results from field work conducted in the autumn 2010 in the Forest District Nowa Dęba. As part of this field work, also the breeding quality of the analyzed pine renewals was assessed. The obtained results indicate that natural regeneration of Scots pine under the conditions of a fresh coniferous forest as well as a fresh mixed coniferous forest is the most reasonable management practice. In wet mixed coniferous forests however, the naturally regenerating Scots pine seedlings are of lower silvicultural quality and growth parameter values compared to those in artificially regenerated stands. In fresh mixed broadleaved forests, naturally regenerated Scot pine trees showed slightly lower silvicultural quality and vitality than artificially regenerated trees. Our results indicate furthermore that there are indeed conditions under which the restoration of Scots pine in the Nowa Dęba Forest District using natural regeneration is preferable. We also found that the employed method of renewing has a significant impact on pine growth parameters in the moist mixed coniferous forest habitat. Naturally renewing pines are characterized by a lower overall viability, but at the same time natural regeneration provides a larger number of individuals with the best viability (1st vitality class), which can be a valuable selection basis for trees used in breeding. *The article is based on the doctoral thesis of Justyna Długosiewicz titled ‘The Economic and breeding effectiveness of the natural and artificial regeneration of pine stands’ conducted at the Faculty of Forestry of the Warsaw University of Life Sciences SGGW.
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Deluzet, Matthieu, Thierry Erudel, Xavier Briottet, David Sheeren, and Sophie Fabre. "Individual Tree Crown Delineation Method Based on Multi-Criteria Graph Using Geometric and Spectral Information: Application to Several Temperate Forest Sites." Remote Sensing 14, no. 5 (2022): 1083. http://dx.doi.org/10.3390/rs14051083.
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Individual tree crown (ITC) delineation in temperate forests is challenging owing to the presence of broadleaved species with overlapping crowns. Mixed coniferous/deciduous forests with characteristics that differ with the type of tree thus require a flexible method of delineation. The ITC delineation method based on the multi-criteria graph (MCG-Tree) addresses this problem in temperate monospecific or mixed forests by combining geometric and spectral information. The method was used to segment trees in three temperate forest sites with different characteristics (tree types, species distribution, planted or natural forest). Compared with a state-of-the-art watershed segmentation approach, our method increased delineation performance by up to 25%. Our results showed that the main geometric criterion to improve delineation quality is related to the crown radius (performance improvement around 8%). Coniferous/deciduous classification automatically adapts the MCG-Tree criteria to the type of tree. Promising results are then obtained to improve delineation performance for mixed forests.
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Nawrot, M., M. Jakubowski, W. Pazdrowski, K. Kaźmierczak, and M. Szymański. "Variation of conducting area in stems of European larch (Larix deciduas) growing in fresh mixed coniferous forest and fresh mixed forest sites." Journal of Forest Science 56, No. 1 (2010): 18–27. http://dx.doi.org/10.17221/45/2009-jfs.
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The paper presents an attempt to determine conducting area (CA), relative conducting area (CA.k<sup>–1</sup>) and mean ring conducting area (CAar) on discs cut at breast height from stems of larch trees growing in fresh mixed coniferous forest and fresh mixed forest sites, representing four age classes and the main crop according to Kraft’s classification. The value of CA increases with an improvement of the social class of tree position in the community, while no such dependences were found for the value of (CA.k<sup>–1</sup>). The parameter CAar, except for one case in age class IV in the fresh mixed coniferous forest site, increases with an improvement of the position a tree takes in the community and differentiates more markedly under the conditions of fresh mixed forest sites. Relative conducting area (CA.k<sup>–1</sup>) decreases markedly with an increase in the age of trees, which is confirmed by high values of the coefficient of determination. Moreover, the significance of differences between individual trees in the main crop according to Kraft and forest site types was tested in terms of the values of CAar. Calculated values may be used to describe the relationships between conducting area and the size of the assimilating organ more precisely than the total sapwood zone.
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Hall, D. K., J. L. Foster, J. R. Irons, and P. W. Dabney. "Airborne bidirectional radiances of snow-covered surfaces in Montana, U.S.A." Annals of Glaciology 17 (1993): 35–40. http://dx.doi.org/10.3189/s0260305500012581.
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Bidirectional radiance measurements of various snow-covered surfaces have been acquired using the Advanced Solid-State Array Spectro-radiometer (ASAS) which was flown on the NASA C-130 aricraft over Glacier National Park, Montana on 14 March 1991. A frozen lake, a snow-covered meadow, a mixed coniferous/deciduous forest and a dense coniferous forest were studied. Knowledge of the bidirectional reflectance characteristics of various snow-covered surfaces is key to calculation of albedo from satellite sensors in the future. While the reflectance characteristics of pure snow targets have been measured from the ground, aircraft and satellites, very few bidirectional reflectance data exist for surface covers of mixed snow and vegetation. Analysis of the 14 March 1991 ASAS data show that the anisotropic reflectance of snow was strong over the snow-covered frozen lake but slightly dampened over the meadow because of the presence of low vegetation. Over the dense coniferous forest, strong backscatter was observed while higher radiances in both the forward and aftward sensor view zenith directions was measured over the mixed forest. Snow that was known to be beneath the coniferous forest canopy was not detected in our data.
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Hall, D. K., J. L. Foster, J. R. Irons, and P. W. Dabney. "Airborne bidirectional radiances of snow-covered surfaces in Montana, U.S.A." Annals of Glaciology 17 (1993): 35–40. http://dx.doi.org/10.1017/s0260305500012581.
Full textAbstract:
Bidirectional radiance measurements of various snow-covered surfaces have been acquired using the Advanced Solid-State Array Spectro-radiometer (ASAS) which was flown on the NASA C-130 aricraft over Glacier National Park, Montana on 14 March 1991. A frozen lake, a snow-covered meadow, a mixed coniferous/deciduous forest and a dense coniferous forest were studied. Knowledge of the bidirectional reflectance characteristics of various snow-covered surfaces is key to calculation of albedo from satellite sensors in the future. While the reflectance characteristics of pure snow targets have been measured from the ground, aircraft and satellites, very few bidirectional reflectance data exist for surface covers of mixed snow and vegetation. Analysis of the 14 March 1991 ASAS data show that the anisotropic reflectance of snow was strong over the snow-covered frozen lake but slightly dampened over the meadow because of the presence of low vegetation. Over the dense coniferous forest, strong backscatter was observed while higher radiances in both the forward and aftward sensor view zenith directions was measured over the mixed forest. Snow that was known to be beneath the coniferous forest canopy was not detected in our data.
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Lee, Sunjeoung, Seunghyun Lee, Joonghoon Shin, Jongsu Yim, and Jinteak Kang. "Assessing the Carbon Storage of Soil and Litter from National Forest Inventory Data in South Korea." Forests 11, no. 12 (2020): 1318. http://dx.doi.org/10.3390/f11121318.
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Research Highlights: The estimation of soil and litter carbon stocks by the Land Use, Land-Use Changes, and Forestry (LULUCF) sectors has the potential to improve reports on national greenhouse gas (GHG) inventories. Background and Objectives: Forests are carbon sinks in the LULUCF sectors and therefore can be a comparatively cost-effective means and method of GHG mitigation. Materials and Methods: This study was conducted to assess soil at 0–30 cm and litter carbon stocks using the National Forest Inventory (NFI) data and random forest (RF) models, mapping their carbon stocks. The three main types of forest in South Kora were studied, namely, coniferous, deciduous, and mixed. Results: The litter carbon stocks (t C ha−1) were 4.63 ± 0.18 for coniferous, 3.98 ± 0.15 for mixed, and 3.28 ± 0.13 for deciduous. The soil carbon stocks (t C ha−1) were 44.11 ± 1.54 for deciduous, 35.75 ± 1.60 for mixed, and 33.96 ± 1.62 for coniferous. Coniferous forests had higher litter carbon stocks while deciduous forests contained higher soil carbon stocks. The carbon storage in the soil and litter layer increased as the forest grew older; however, a significant difference was found in several age classes. For mapping the soil and litter carbon stocks, we used four random forest models, namely RF1 to RF4, and the best performing model was RF2 (root mean square error (RMSE) (t C ha−1) = 1.67 in soil carbon stocks, 1.49 in soil and litter carbon stocks). Our study indicated that elevation, accessibility class, slope, diameter at breast height, height, and growing stock are important predictors of carbon stock. Soil and litter carbon stock maps were produced using the RF2 models. Almost all prediction values were appropriated to soil and litter carbon stocks. Conclusions: Estimating and mapping the carbon stocks in the soil and litter layer using the NFI data and random forest models could be used in future national GHG inventory reports. Additionally, the data and models can estimate all carbon pools to achieve an accurate and complete national GHG inventory report.
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Данилов, Д. А., and А. А. Яковлев. "Distribution of mixed coniferous stands in the Luzhsko-Volkhovsky landscape district." Известия СПбЛТА, no. 234 (April 5, 2021): 80–101. http://dx.doi.org/10.21266/2079-4304.2021.234.80-101.
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Смешанные древостои с преобладанием сосны и ели занимают территории с оптимальными лесорастительными условиями, в отличие от монодоминантных насаждений. Условно чистые древостои в большинстве случаев приурочены к экстремальным условиям местообитания или обусловлены созданием лесных культур. Среди смешанных древостоев с преобладанием хвойных пород однозначно только хвойно-лиственные, а именно – елово-лиственные древостои, связываются с антропогенным воздействием на географический ландшафт. В каждом отдельно взятом ландшафте будет формироваться отличное распределение типов хвойных насаждений по лесопокрытой площади в зависимости от почвенно-гидрологических условий. Оценка пространственного распределения смешанных хвойных древостоев в различных типах леса позволяет дать точную экологическую характеристику и оценку ландшафта и оценить его антропогенную изменённость. Рассматриваются особенности распространения смешанных древостоев с преобладанием сосны и ели в наиболее представленных типах леса в основных ландшафтах Лужско-Волховского ландшафтного округа Ленинградской области. Проведён анализ ландшафтов по распределению покрытой лесом площади по почвенно-гидрологическим условиям и основным обобщённым группам типов леса. Присутствие сложного комплекса холмисто-моренных, камовых, озовых урочищ, чередующихся с заболоченными котловинами и озёрами практически во всех рассмотренных ландшафтах, позволяет сделать заключение, что приуроченность смешанных хвойных древостоев связана с фактором переходных форм рельефа от одной ландшафтной группы к другой. Типологическая приуроченность хвойных полидоминантных древостоев является закономерной для зеленомошной серии типов леса данного ландшафтного округа. Mixed woodlands with a predominance of pine and spruce occupy territory with optimal forest-growing conditions, unlike monodominant plantations. Conditionally clean woodlands are in most cases shortened to extreme habitat conditions or due to the creation of forest crops. Among mixed woodlands with a predominance of conifers, unambiguously only coniferous-deciduous, namely spruce-deciduous woodlands, are associated with anthropogenic effects on the geographical landscape. In each individual landscape, an excellent distribution of the types of coniferous plantations along the covered area will be formed, depending on soil and hydrological conditions. The assessment of the spatial distribution of mixed coniferous trees in different types of forest allows to give an accurate ecological characteristic and assessment of the landscape and to assess its anthropogenic variation. The article considers the distribution features of mixed woodlands with a predominance of pine and spruce in the most represented types of forest in the main landscapes of the Luga-Volkhov landscape district of the Leningrad region. An analysis of landscapes was carried out on the distribution of forest-covered area according to soil-hydrological conditions and the main generalized groups of forest types. The presence of a complex of hilly-moraine, stone, oze tracts alternating with swampy basins and lakes in almost all the landscapes considered allows us to conclude that the confluence of mixed coniferous woodlands is associated with the factor of the transition forms of relief from one landscape group to another. The typological confluence of coniferous polydominant woodlands is natural for a green-haired series of forest types of this landscape district.
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Han, Peng-Bin, Shu-Gang Lu, and Cindy Q. Tang. "Forest and Population Characteristics of Vulnerable Relict Tsuga forrestii Downie in China." Diversity 17, no. 3 (2025): 148. https://doi.org/10.3390/d17030148.
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Tsuga forrestii Downie, a vulnerable species endemic to China, is confined to small, fragmented habitats in the northwestern Yunnan and southwestern Sichuan Provinces, China. Understanding the current status of its communities and populations is crucial for protecting existing natural forest resources. We surveyed 33 plots in Yunnan and Sichuan, where T. forrestii is the primary dominant species. We analyzed their community characteristics including vertical stratification, species diversity, and population structure, and classified them into four distinct forest types: (1) Tsuga forrestii evergreen coniferous forest; (2) Tsuga forrestii-Lithocarpus variolosus evergreen coniferous and broad-leaved mixed forest; (3) Tsuga forrestii-Quercus guyayifolia evergreen coniferous and broad-leaved mixed forest; (4) Tsuga forrestii-Abies forrestii evergreen coniferous forest. These forests exhibited a multilayered vertical structure, and T. forrestii as a dominant species appeared in the arborous and shrub layers, and the associated taxa were mainly species of Abies, Lithocarpus, Quercus, Castanopsis, and Rhododendron. No significant differences in species richness or diversity indices or phylogenetic relatedness metrics among the forest types were found. The maximum age of the remaining wild specimens was 344 years, with individuals under 20 years or over 170 years old being rare. The average growth rate of T. forrestii, based on ring width, fluctuated over time, and the range of mean values was 0.92 to 3.31 mm/year. Established seedlings/saplings were rare and mainly found in unstable microhabitats. These findings highlight the poor regeneration and a decline in its populations. Improving its regeneration status is crucial to maintaining its population status.
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Bondaruk, M. A., and O. G. Tselishchev. "PHYTOINDICATION OF EDAPHIC REGIMES OF FOREST ECOSYSTEM ECOTOPES FOR DNIPRO LEFT-BANK FOREST-STEPPE FORESTRY DISTRICT OF UKRAINE." Forestry and Forest Melioration, no. 132 (February 5, 2018): 94–104. http://dx.doi.org/10.33220/1026-3365.132.2018.94.
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Issues of phytoindication and phytomonitoring of major ecological factors for large-scale regional (zonal) investigations are analyzed. The presented methodical approaches of phytoindication and examples of their application show the prospects of this scientific direction for the regional (zonal) ecological monitoring of edaphic regimes in forest ecotopes. The subjects of research were the first level monitoring plots (146 plots) located within Dnipro Left Bank Forest-Steppe forestry district, Ukraine. A concept of “eco-background”, i. e. the background factors of forests (a range of values within the limits of standard deviations), in relation to which the direction and intensity of edaphic and climatic processes are measured in the forest ecotopes of specific region, and within the region, in the ecotopes of the coniferous, mixed and broad-leaved forests, is used for the comparative monitoring of fluctuations and dynamics of the ecological regimes in relation to typical and zonally-provided values in the forest ecotopes of the region. The total edaphic eco-background (including hydro-background, acido-background, total salt-background, carbonate content-background, nitro-background) was investigated for the district’s forests and within the district, the separate edaphic eco-backgrounds of coniferous, mixed and broad-leaved forests.
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Neirynck, J., and R. Ceulemans. "Bidirectional ammonia exchange above a mixed coniferous forest." Environmental Pollution 154, no. 3 (2008): 424–38. http://dx.doi.org/10.1016/j.envpol.2007.11.030.
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Patton, David R., and J. Robert Vahle. "Cache and Nest Characteristics of the Red Squirrel in an Arizona Mixed-Conifer Forest." Western Journal of Applied Forestry 1, no. 2 (1986): 48–51. http://dx.doi.org/10.1093/wjaf/1.2.48.
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Abstract The red squirrel (Tamiasciurus hudsonicus) is closely associated with mature- to old-growth forest conditions of large coniferous trees, dense canopy closure, and a structure of all-aged trees. In Arizona, mixed-conifer forests with these stand conditions provide red squirrels with suitable opportunities for food gathering, sites for food caching, and trees for nesting. Douglas-fir (Pseudotsuga menziesii), white fir (Abies con-color), and blue spruce (Picea pungens) are the most important species in red squirrel habitat. Red squirrels contribute to the functioning of the forest ecosystem by spreading the spores of mycorrhizal underground fungi, which may be necessary for the survival of coniferous trees. West. J. Appl. For. 1:48-51, April 1986
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Xu, Qigang, Fan Yang, Sheng Hu, Xiao He, and Yifeng Hong. "Tree Height–Diameter Model of Natural Coniferous and Broad-Leaved Mixed Forests Based on Random Forest Method and Nonlinear Mixed-Effects Method in Jilin Province, China." Forests 15, no. 11 (2024): 1922. http://dx.doi.org/10.3390/f15111922.
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Objective: The purpose of this article was to use the Random Forest method and nonlinear mixed-effects method to develop a model for determining tree height–diameter at breast height (DBH) for a natural coniferous and broad-leaved mixed forest in Jilin Province and to compare the advantages and disadvantages of the two methods to provide a basis for forest management practice. Method: Based on the Chinese national forest inventory data, the Random Forest method and nonlinear mixed-effects method were used to develop a tree height–DBH model for a natural coniferous and broad-leaved mixed forest in Jilin Province. Results: The Random Forest method performed well on both the fitting set and validation set, with an R2 of 0.970, MAE of 0.605, and RMSE of 0.796 for the fitting set and R2 of 0.801, MAE of 1.44 m, and RMSE of 1.881 m for the validation set. Compared with the nonlinear mixed-effects method, the Random Forest model improved R2 by 33.83%, while the MAE and RMSE decreased by 67.74% and 66.44%, respectively, in the fitting set; the Random Forest model improved R2 by 9.88%, while the MAE and RMSE decreased by 14.38% and 12.05%, respectively, in the validation set. Conclusions: The tree height–DBH model constructed based on the Random Forest method had higher prediction accuracy for a natural coniferous and broad-leaved mixed forest in Jilin Province and had stronger adaptability for higher-dimensional data, which can be used for tree height prediction in the study area.
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Załuski, Tomasz. "Vegetation Transformations of Kujawy-Pomerania Region in the Last Twenty Years Period." Folia Biologica et Oecologica 7 (December 12, 2011): 75–98. http://dx.doi.org/10.2478/v10107-009-0017-y.
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This paper contents dynamic tendencies analysis results of Kujawy-Pomerania region (N Poland) for a 20-year time period. Acreage changes as well as structure and species composition transformations of forest and shrub vegetation (associations) and non-forest vegetation (alliances) were evaluated. Main factors influencing on regressive and progressive changes were set out. Analysis was relied on results of geobotanical research and observations of selected objects. Regressive changes were noted for i.a. thermophilous oak forests, dry and fresh coniferous forests, aquatic, halophytic, pasture vegetation, vegetation of Molinion and Cnidion meadows, heaths and xerothermic grasslands. Whereas progressive were observed in case of mixed coniferous forests, mesophytic shrubs, rush and tall herbs vegetation, fresh meadows and some ruderal communities.