Forests最新文献

{"title":"Linear Cutting Performance Tests and Parameter Optimization of Poplar Branches Based on RSM and NSGA-II","authors":"Liang Zhao, Weidong Yuan, Linyun Xu, Shouxiang Jin, Wangbin Cui, Jiangkun Xue, Hongping Zhou","doi":"10.3390/f15010146","DOIUrl":"https://doi.org/10.3390/f15010146","url":null,"abstract":"To reduce the cutting force and cutting energy consumption during the operation of tree-climbing pruning machines for poplar trees, a linear cutting test bench device for branches was designed according to the growth characteristics of poplar branches and pruning forestry requirements in this study. Firstly, the cutting mechanical analysis of poplar branches was carried out to explore the significance parameters affecting the cutting force, and then the cutting performance test and parameter optimization of poplar branches was carried out through the response surface method (RSM). The test results indicated that cutting speed, tool edge angle and tool back angle had significant effects on the ultimate shear stress, cutting power consumption per unit area, and the branch damage rate of poplar branches, and the established regression equation demonstrated high goodness of fit. Meanwhile, a second-order regression mathematical model was developed between ultimate shear stress, cutting the power consumption per unit area of the cut and the branch damage rate, and the significance parameter. The non-dominated Sorting Genetic Algorithm II (NSGA-II) was used for multi-objective optimization computation to obtain the optimal combination of cutting parameters as 3.02 m/s for cutting speed, 15° for tool edge angle, and 3° for tool back angle. In this case, the ultimate shear stress, cutting power consumption per unit area, and branch damage rate of poplar branches were small, which were 346.63 kPa, 9.35 mJ/mm2, and 12.36%, respectively. Through the test verification, it can be seen that the relative error between the verification test and the predicted value of model was less than 7%. Moreover, under a cutting tool edge angle of 15°, the ultimate shear stress, cutting power consumption per unit area, and branch damage rate were, respectively, reduced by 17.29%, 14.98%, and 34.21% compared with those under a cutting tool edge angle of 20°, which verifies the validity and reliability of the test results and the research method. This study can provide data support and reference for the research and development of energy-efficient poplar tree-climbing pruning equipment and related branch-cutting performance tests.","PeriodicalId":12339,"journal":{"name":"Forests","volume":"53 14","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139441193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantification and Proxy Indicators of the Carbon Pool in Urban Tree Litterfall: A Case Study of Urban Green Spaces in Beijing","authors":"Yujuan Cao, Xinyu Li, Yanming Li, Jia Guo, Yali Qi","doi":"10.3390/f15010144","DOIUrl":"https://doi.org/10.3390/f15010144","url":null,"abstract":"As major carbon (C) pools in cities, urban green spaces play a crucial role in reducing atmospheric carbon. To determine the importance of litterfall C storage in urban green spaces, we selected the leaf area index (LAI) as a proxy indicator for litterfall C density (LCD), and established a log-linear regression model between LCD and LAI to predict the annual litterfall C pool in large-scale urban green spaces using Sentinel-2 satellite remote sensing data. Forty-five sample units were randomly selected in typical urban green spaces in Beijing, China. A high-temperature combustion method was used to measure the LCD of the sampling units, and stepwise linear regression was used to filter the proxy indicator for LCD. The annual litterfall C pool in regions within the Fifth Ring Road was also estimated with inversion using remote sensing data. From 2015 to 2021, the estimated annual litterfall C pool was in the range of 4.5–5.8 × 1010 g, i.e., approximately 18.9% of the total C storage recorded for the urban green space, which was far greater than that observed in forest ecosystems. We concluded that the litterfall C pool in urban green spaces is seriously underestimated, and that urban tree litterfall has the potential to reduce greenhouse gas emissions if used as a carbon-neutral resource.","PeriodicalId":12339,"journal":{"name":"Forests","volume":"2 12","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139439487","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First-Year Mortality of Four Early-Successional Species on Severely Degraded Sites in Eastern Canada as Influenced by a Factorial of Site Preparation Treatments","authors":"Dominic Galea, John E. Major","doi":"10.3390/f15010143","DOIUrl":"https://doi.org/10.3390/f15010143","url":null,"abstract":"Barren, severely disturbed sites lacking soil, such as mine sites and waste deposit sites, present severe challenges to ecological service restoration because of high temperatures, solar radiation, and wind speeds; extreme temperature changes; and low soil moisture and nutrient availability. An ecological restoration experiment using three site preparation treatments was conducted. Straw (S), Meri-Crusher (MC), and coarse woody debris (CWD) were assessed in a site, no site preparation 2 × 2 × 2 factorial, including a control treatment, on sites barren for 25 years. In addition, four early-successional species: white birch (WB, Betula papyrifera Marsh), gray birch (GB, Betula populifolia Marsh), green alder (GA, Alnus viridis Vill. ssp. crispa Ait) and speckled alder (SA, Alnus incana L. ssp. rugosa Du Roi), were examined for mortality. Mortality was measured after three time periods, summer-related 2021, winter-related, and frost heave mortality (spring 2022). Summer-related mortality was predominantly influenced by S treatments (reduced mortality) and their interactions. Straw’s ability to retain moisture strongly suggests it mitigated summer-related drought mortality. S interactions were not rank changes but magnitude effects. The species × straw interaction showed that SA had the greatest magnitude difference, with 25% and 3.6% summer-related mortality for NS and S treatments, respectively. SA, a hydrophilic species, accounted for nearly half the total summer-related mortality, and there were strong species effects and species interactions. The full combination of site preparation treatments had the lowest summer-related mortality, at 1%. Winter-related mortality only affected 1.9% of the total sample size, and there were no species effects or interactions, but contrary to other results, S was the leading cause of mortality due to fungal presence found on expired seedlings. For frost heave mortality, it was clear that the S treatment was effective, with 1.2% and 20.7% overall mortality for S and NS, respectively. MC alone had the greatest negative effect, with 46.9% frost heave mortality; however, when interacting with S or CWD, the mortality decreased substantially. Frost heave had no species interactions and only a species effect, with SA having the greatest mortality. Over the first full year, MC alone and control had the greatest mortality, with 60% and 38%, respectively, after one year. Overall, one-year mortality showed S reduced mortality by 27% and CWD by 19%, while MC increased mortality by approximately 4%. When treatments were combined in any way, mortality dropped significantly, showing an additive effect, with the three-combination treatment resulting in the lowest one-year mortality, of only 3.1%. Straw provided the strongest effect, both as an effective barrier to moisture evaporation, providing up to 10% more soil moisture under dry conditions and provided an effective thermal barrier that substantially reduced the frost heave ","PeriodicalId":12339,"journal":{"name":"Forests","volume":"2 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139439790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Wildfires’ Effect on Soil Properties and Bacterial Biodiversity of Postpyrogenic Histic Podzols (Middle Taiga, Komi Republic)","authors":"E. Chebykina, E. Abakumov, A. Kimeklis, G. Gladkov, E. Andronov, A. Dymov","doi":"10.3390/f15010145","DOIUrl":"https://doi.org/10.3390/f15010145","url":null,"abstract":"Data on the main properties of Histic Podzols in the pine forests of semi-hydromorphic landscapes in the middle taiga of the Komi Republic after forest fires are presented. A decrease in topsoil horizon thickness by more than 7.6 times, an increase in litter density by 6 times, and a decrease in litter stock by 4 times were observed in postfire soil. There was an increase in carbon content in the pyrogenic horizon (48%) and in the upper part of the podzolic horizon—from 0.49 at the control plot to 1.16% after the fire. The accumulation of all studied trace metals (Cu—from 2.5 to 6.8 mg × kg−1; Zn—from 35.7 to 127.4 mg × kg−1; Ni—from 2.2 to 8.1 mg × kg−1; Pb—from 1.4 to 28.3 mg × kg−1; Cd—from 0.3 to 1.1 mg × kg−1) in soils after wildfires was recorded. The effect of the fire can be traced to a depth of approximately 20–30 cm. A significant influence of the pyrogenic factor on the alpha and beta bacterial diversity was noted. The bacterial response to a forest fire can be divided into an increased proportion of spore-forming and Gram-negative species with complex metabolism as well.","PeriodicalId":12339,"journal":{"name":"Forests","volume":"3 7","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139439248","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Normal Difference Vegetation Index Simulation and Driving Analysis of the Tibetan Plateau Based on Deep Learning Algorithms","authors":"Xi Liu, Guoming Du, Haoting Bi, Zimou Li, Xiaodie Zhang","doi":"10.3390/f15010137","DOIUrl":"https://doi.org/10.3390/f15010137","url":null,"abstract":"Global climate warming has profoundly affected terrestrial ecosystems. The Tibetan Plateau (TP) is an ecologically vulnerable region that emerged as an ideal place for investigating the mechanisms of vegetation response to climate change. In this study, we constructed an annual synthetic NDVI dataset with 500 m resolution based on MOD13A1 products from 2000 to 2021, which were extracted by the Google Earth Engine (GEE) and processed by the Kalman filter. Furthermore, considering topographic and climatic factors, a thorough analysis was conducted to ascertain the causes and effects of the NDVI’s spatiotemporal variations on the TP. The main findings are: (1) The vegetation coverage on the TP has been growing slowly over the past 22 years at a rate of 0.0134/10a, with a notable heterogeneity due to its topography and climate conditions. (2) During the study period, the TP generally showed a “warming and humidification” trend. The influence of human activities on vegetation growth has exhibited a favorable trajectory, with a notable acceleration observed since 2011. (3) The primary factor influencing NDVI in the southeastern and western regions of the TP was the increasing temperature. Conversely, vegetation in the northeastern and central regions was mostly regulated by precipitation. (4) Combined with the principal component analysis, a PCA-CNN-LSTM (PCL) model demonstrated significant superiority in modeling NDVI sequences on the Tibetan Plateau. Understanding the results of this paper is important for the sustainable development and the formulation of ecological policies on the Tibetan Plateau.","PeriodicalId":12339,"journal":{"name":"Forests","volume":"20 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139444362","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Physiological Responses Revealed Static Magnetic Fields Potentially Improving the Tolerance of Poplar Seedlings to Salt Stress","authors":"Jihuai Hu, Haojie Zhang, Wenhao Han, Nianzhao Wang, Shuqi Ma, Fengyun Ma, Huimei Tian, Yanping Wang","doi":"10.3390/f15010138","DOIUrl":"https://doi.org/10.3390/f15010138","url":null,"abstract":"Magnetic fields play an important role in regulating plant growth and development, especially in improving plant stress tolerance. However, the physiological mechanism underlying the magnetic effects is still unclear. Here, we examined changes in reactive oxygen species (ROS) levels and ion flux in poplar (Populus × deltoides ‘Lulin-2’) seedling roots under salt stress in a static magnetic field (SMF). SMF treatment significantly increased seedling growth and mitigated the effects of salt stress on root growth. Furthermore, SMF treatment activated ROS and calcium signals in poplar roots. Relative to the SMF treatment group, control plants had significantly higher levels of cytoplasmic free Ca2+ ([Ca2+]cyt) and ROS following exposure to high salt concentrations. Under salt conditions, SMF treatment reduced increases in Na+ concentrations and maintained stable K+ and Ca2+ concentrations and K+/Na+ and Ca2+/Na+ ratios. NMT analysis suggests that SMF treatment may drive cation effluxes in poplar seedling roots. Susceptibility tests of Na+-transport inhibitors indicated that SMF treatment contributed to Na+ repulsion and H+ uptake under salt stress. Moreover, SMF exposure allowed roots to retain the ability to reduce salt-induced K+ and Ca2+ root effluxes, and qRT-PCR results demonstrate that SMF treatment can increase the expression of stress-responsive genes such as PtrRBOHF, PtrNHX1 and PtrHA5 in poplar seedlings. Therefore, we conclude that treating poplar seedlings with SMF can help them establish a stable tolerance to salt stress by regulating ROS, [Ca2+]cyt, and their regulatory networks. This study examined the physiological responses of poplar to SMF exposure under salt stress, providing insights into plant magnetobiological effects.","PeriodicalId":12339,"journal":{"name":"Forests","volume":"5 4","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139444304","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improved Tree Segmentation Algorithm Based on Backpack-LiDAR Point Cloud","authors":"Dongwei Zhu, Xianglong Liu, Yili Zheng, Liheng Xu, Qingqing Huang","doi":"10.3390/f15010136","DOIUrl":"https://doi.org/10.3390/f15010136","url":null,"abstract":"For extracting tree structural data from LiDAR point clouds, individual tree segmentation is of great significance. Most individual tree segmentation algorithms miss segmentation and misrecognition, requiring manual post-processing. This study utilized a hierarchical approach known as segmentation based on hierarchical strategy (SHS) to improve individual tree segmentation. The tree point cloud was divided into the trunk layer and the canopy layer to carry out trunk detection and canopy segmentation, respectively. The effectiveness of SHS was evaluated on three mixed broadleaf forest plots. The segmentation efficacy of SHS was evaluated on three mixed broadleaf forest plots and compared with the point cloud segmentation algorithm (PCS) and the comparative shortest-path algorithm (CSP). In the three plots, SHS correctly identified all the trunk portion, had a recall (r) of 1, 0.98, and 1, a precision (p) of 1, and an overall segmentation rate (F) of 1, 0.99, and 1. CSP and PCS are less accurate than SHS. In terms of overall plots, SHS had 10%–15% higher F-scores than PCS and CSP. SHS extracted crown diameters with R2s of 0.91, 0.93, and 0.89 and RMSEs of 0.24 m, 0.23 m, and 0.30 m, outperforming CSP and PCS. Afterwards, we evaluate the three algorithms’ findings, examine the SHS algorithm’s parameters and constraints, and discuss the future directions of this research. This work offers an enhanced SHS that improves upon earlier research, addressing missed segmentation and misrecognition issues. It improves segmentation accuracy, individual tree segmentation, and provides both theoretical and data support for the LiDAR application in forest detection.","PeriodicalId":12339,"journal":{"name":"Forests","volume":"107 5","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139444629","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Epigenetics as a Regulator of Tree Specialized Metabolites In Vitro Production","authors":"Stéphane Maury","doi":"10.3390/f15010141","DOIUrl":"https://doi.org/10.3390/f15010141","url":null,"abstract":"Specialized metabolites correspond to millions of natural molecules from different chemical families depending on plant taxa that play a key role in ecological interactions during their life cycle. Due to their chemical properties, plants’ specialized metabolites have been exploited for a long time for various industrial applications. However, the limitations in natural population resources as well as the difficulties of their cultivation in terms of production quality or product safety have not always been satisfactory, notably for perennials such as forest trees. Reliable and eco-adapted practices for the production of specialized metabolites such as in vitro cultures provide a useful and powerful alternative to agronomic cultures. Modern omics have allowed the identification of metabolite pathways but have also raised the question of their complex regulation to improve their production. Among the major regulatory players, epigenetics have been shown in recent years to be involved in plant development and the response to environmental variations. Here, the state of the art concerning the epigenetic control of plant specialized metabolite in vitro production as well as the challenges in forest trees are presented.","PeriodicalId":12339,"journal":{"name":"Forests","volume":"93 7","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139444533","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Elevation-Dependent Natural Regeneration of Abies georgei var. smithii Forest in Southeastern Tibet","authors":"Ruihong Wang, Ronggui Hu, Yu-peng Wu, Muhammad Shaaban, Tao Zhang, Gang Pan, Jie Lu, Yanbin Jiang","doi":"10.3390/f15010142","DOIUrl":"https://doi.org/10.3390/f15010142","url":null,"abstract":"The comprehensive impacts of biotic and abiotic factors on the natural regeneration of Abies georgei var. smithii (Abies) forests in Tibet are not thoroughly understood. To address this gap, our study focused on the regeneration densities of Abies seedlings, saplings, and small trees across 21 plots (each 20 m × 20 m) along an elevation gradient from 3730 m to 4330 m in the Sygera Mountains of Southeastern Tibet. We meticulously measured a suite of 11 variables that describe stand structures and ecological conditions. Through analyses using Spearman’s correlation analysis, hierarchical partitioning, and multiple linear regression, we identified key ecological drivers for successful Abies regeneration. Our results highlighted a peak in the abundance of seedlings, saplings, and small trees at an elevation of 3930 m. As the elevation rose from 3730 m to 4330 m, we observed an initial increase followed by a decrease in canopy cover (canopy), mother tree density (MotherT), 1000-seed weight (SeedW), litter thickness (LitterT), moss cover (MossC), moss thickness (MossT), soil moisture (SM), and soil bulk density, while mean annual temperature and soil depth to permafrost consistently decreased. The critical ecological drivers for Abies natural regeneration were identified as follows: MossT was pivotal for seedling density; canopy and MossC were influential for sapling density, and MotherT was the main factor affecting the density of small trees. This study suggests that a high density of mother trees and a thick and highly covered layer of moss are conducive to the natural regeneration of Abies in the Sygera Mountains. Understanding the current status of regeneration is vital for informing conservation and management strategies for Abies forests in Tibet.","PeriodicalId":12339,"journal":{"name":"Forests","volume":"36 11","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139442796","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Silvicultural Treatments on Nothofagus glauca Forests Regarding Canopy Structure Patterns, Solar Radiation Transmission, and Tree Regeneration","authors":"Rómulo E Santelices-Moya, Á. Promis, Miguel Peralta-Aguilera, Antonio M. Cabrera-Ariza","doi":"10.3390/f15010134","DOIUrl":"https://doi.org/10.3390/f15010134","url":null,"abstract":"This study focuses on the natural regeneration of Nothofagus glauca, a critical component of temperate forests in the Mediterranean region of the Southern Hemisphere in Chile. Various harvesting and canopy opening methods were evaluated to understand their impact on the regeneration of this species. A “mast seeding” behavior was observed in seed production, with alternating years of high and low production. Seed viability was affected by lepidopteran infestation and extreme weather events. The results indicate variable seed quantity and quality, influencing regeneration. First-year seedling mortality was significant, reaching up to 95%, and regeneration decreased annually. Additionally, changes in canopy opening and solar radiation transmission were analyzed, revealing significant post-harvest modifications. This study provides valuable insights for the sustainable management of Mediterranean forests, emphasizing the importance of considering seed production variability and regeneration dynamics in decision-making processes.","PeriodicalId":12339,"journal":{"name":"Forests","volume":"31 3","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139444016","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}