Ilze Matisone, G. Snepsts, Dārta Kaupe, Sebastian Hein, Raitis Rieksts-Riekstiņš, Ā. Jansons
In the Eastern Baltics, climatic changes are expected to alter forest composition favouring broadleaved species. The height growth of trees influences the productivity of stands and the competitiveness of species, particularly in mixed sites, thus emphasising the necessity for accurate projections. Accordingly, height models are paramount for projecting productivity and yields of stands. As tree height growth dynamics vary regionally, regional or even local models are needed. Based upon 214 National Forest Inventory plots and 510 individual canopy trees, dominant height growth for small-leaved lime (Tilia cordata Mill.) and Norway maple (Acer platanoides L.) in Latvia were analysed. Height growth was modelled using a generalised algebraic difference approach, testing several non-linear equations. The Sloboda (for lime) and Hossfeld I (for maple) models showed the best fit and were the most realistic, predicting slower initial and middle-age (maturing period) growth, yet also displayed higher asymptotes compared to Western Europe. The predicted height at the age of 80 years was 14–33 m and 13–34 m for lime and maple, accordingly. A longer establishment period and later growth culmination suggest longer rotation, highlighting the assessment of long-term risks. In this case, supplementation of the models with climatic effects appears advantageous.
{"title":"Analysis of Height Growth Suggests Moderate Growth of Tilia cordata and Acer platanoides at the Native Hemiboreal Stands in Latvia","authors":"Ilze Matisone, G. Snepsts, Dārta Kaupe, Sebastian Hein, Raitis Rieksts-Riekstiņš, Ā. Jansons","doi":"10.3390/f15010007","DOIUrl":"https://doi.org/10.3390/f15010007","url":null,"abstract":"In the Eastern Baltics, climatic changes are expected to alter forest composition favouring broadleaved species. The height growth of trees influences the productivity of stands and the competitiveness of species, particularly in mixed sites, thus emphasising the necessity for accurate projections. Accordingly, height models are paramount for projecting productivity and yields of stands. As tree height growth dynamics vary regionally, regional or even local models are needed. Based upon 214 National Forest Inventory plots and 510 individual canopy trees, dominant height growth for small-leaved lime (Tilia cordata Mill.) and Norway maple (Acer platanoides L.) in Latvia were analysed. Height growth was modelled using a generalised algebraic difference approach, testing several non-linear equations. The Sloboda (for lime) and Hossfeld I (for maple) models showed the best fit and were the most realistic, predicting slower initial and middle-age (maturing period) growth, yet also displayed higher asymptotes compared to Western Europe. The predicted height at the age of 80 years was 14–33 m and 13–34 m for lime and maple, accordingly. A longer establishment period and later growth culmination suggest longer rotation, highlighting the assessment of long-term risks. In this case, supplementation of the models with climatic effects appears advantageous.","PeriodicalId":12339,"journal":{"name":"Forests","volume":"114 5","pages":""},"PeriodicalIF":2.9,"publicationDate":"2023-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138959647","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}
Stump–root systems consist of aboveground stumps and underground coarse roots after timber harvesting. Stump–root systems are the primary source of coarse woody debris (CWD) in plantations, and they play a crucial role in the material cycle, energy flow, and biodiversity of Eucalyptus plantation ecosystems. However, there is limited knowledge about the changes in elemental stock within this CWD type during decomposition. To address this gap, we conducted a study on Eucalyptus urophylla × E. grandis stump–root systems at various times (0, 1, 2, 3, 4, 5, and 6 years) after clearcutting. Our aim was to investigate the stock changes in eight elements (K, Ca, Mg, S, Fe, Mn, Cu, and Zn) within the stumps and coarse roots over time and their decay levels, and we analyzed the relationship between elemental stocks and the physical, chemical, and structural components of stump–root systems. Our findings revealed the following: (1) The majority of each element’s stock within the stump–root system was found in the coarse roots. The elemental stocks in both stumps and coarse roots decreased as time passed after clearcutting and as decay progressed. (2) Notably, the elemental stocks in stumps and coarse roots were significantly higher than in other treatments during the initial 0–2 years after clearcutting and at decay classes I and II. In terms of elemental stocks, stumps from all clearcutting times or decay classes had the highest K stock, followed by Ca and Fe. Mg, Mn, and S stocks were lower than the first three, while Zn and Cu stocks were very low. The ordering of elemental stocks from high to low in the stump–root systems generally aligned with that of the coarse roots. (3) The residual rates of K, Mg, and Mn stocks in the stump–root systems fit the negative exponential model well. It took approximately 1 to 3.5 years for a 50% loss of the initial stocks of these elements and 5 to 10 years for a 95% loss. (4) The large amount of biomass in the stump–root system is the long-term nutrient reservoir of plantations, and any factor related to biomass loss affects the magnitude and duration of the nutrient reservoir, such as N, P, stoichiometric ratios, density, water-holding capacity, and hemicellulose. These findings contribute to a better understanding of the nutrient elemental dynamics and ecological functions of stump–root systems in Eucalyptus plantations.
树桩-树根系统由木材采伐后的地上树桩和地下粗根组成。树桩-树根系统是人工林中粗木质碎屑(CWD)的主要来源,在桉树人工林生态系统的物质循环、能量流动和生物多样性方面起着至关重要的作用。然而,人们对这种 CWD 在分解过程中的元素储量变化了解有限。为了填补这一空白,我们对桉树 × 桉树树桩-根系系统进行了一项研究,研究时间为砍伐后的不同时期(0、1、2、3、4、5 和 6 年)。我们的目的是研究树桩和粗根中八种元素(K、Ca、Mg、S、Fe、Mn、Cu 和 Zn)的储量随时间的变化及其衰变程度,并分析元素储量与树桩-根系统的物理、化学和结构成分之间的关系。我们的研究结果表明(1) 在树桩-根系中,每种元素的大部分存量都存在于粗根中。随着砍伐后时间的推移和腐烂程度的加深,树桩和粗根中的元素储量都在减少。(2)值得注意的是,在砍伐后最初的 0-2 年内,以及在腐烂等级 I 和 II 时,树桩和粗根的元素储量明显高于其他处理。就元素储量而言,所有砍伐时间或腐烂等级的树桩中 K 储量最高,其次是 Ca 和 Fe。镁、锰和硫的储量低于前三者,而锌和铜的储量则非常低。树桩-根系中元素储量从高到低的排序与粗根的排序基本一致。(3) 树桩-根系中钾、镁和锰元素储量的残留率非常符合负指数模型。这些元素的初始存量损失 50%大约需要 1 至 3.5 年,损失 95%大约需要 5 至 10 年。(4) 树桩-根系中的大量生物量是种植园的长期营养库,与生物量损失有关的任何因素都会影响营养库的规模和持续时间,如氮、磷、化学计量比、密度、持水能力和半纤维素。这些发现有助于更好地了解桉树种植园中树桩-根系的营养元素动态和生态功能。
{"title":"Nutrient Element Stocks and Dynamic Changes in Stump–Root Systems of Eucalyptus urophylla × E. grandis","authors":"Zhushan Xie, Xiang Liang, Haiyu Liu, Xiangsheng Deng, Fei Cheng","doi":"10.3390/f15010001","DOIUrl":"https://doi.org/10.3390/f15010001","url":null,"abstract":"Stump–root systems consist of aboveground stumps and underground coarse roots after timber harvesting. Stump–root systems are the primary source of coarse woody debris (CWD) in plantations, and they play a crucial role in the material cycle, energy flow, and biodiversity of Eucalyptus plantation ecosystems. However, there is limited knowledge about the changes in elemental stock within this CWD type during decomposition. To address this gap, we conducted a study on Eucalyptus urophylla × E. grandis stump–root systems at various times (0, 1, 2, 3, 4, 5, and 6 years) after clearcutting. Our aim was to investigate the stock changes in eight elements (K, Ca, Mg, S, Fe, Mn, Cu, and Zn) within the stumps and coarse roots over time and their decay levels, and we analyzed the relationship between elemental stocks and the physical, chemical, and structural components of stump–root systems. Our findings revealed the following: (1) The majority of each element’s stock within the stump–root system was found in the coarse roots. The elemental stocks in both stumps and coarse roots decreased as time passed after clearcutting and as decay progressed. (2) Notably, the elemental stocks in stumps and coarse roots were significantly higher than in other treatments during the initial 0–2 years after clearcutting and at decay classes I and II. In terms of elemental stocks, stumps from all clearcutting times or decay classes had the highest K stock, followed by Ca and Fe. Mg, Mn, and S stocks were lower than the first three, while Zn and Cu stocks were very low. The ordering of elemental stocks from high to low in the stump–root systems generally aligned with that of the coarse roots. (3) The residual rates of K, Mg, and Mn stocks in the stump–root systems fit the negative exponential model well. It took approximately 1 to 3.5 years for a 50% loss of the initial stocks of these elements and 5 to 10 years for a 95% loss. (4) The large amount of biomass in the stump–root system is the long-term nutrient reservoir of plantations, and any factor related to biomass loss affects the magnitude and duration of the nutrient reservoir, such as N, P, stoichiometric ratios, density, water-holding capacity, and hemicellulose. These findings contribute to a better understanding of the nutrient elemental dynamics and ecological functions of stump–root systems in Eucalyptus plantations.","PeriodicalId":12339,"journal":{"name":"Forests","volume":" 2","pages":""},"PeriodicalIF":2.9,"publicationDate":"2023-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138963209","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}
Salix psammophila, classified under the Salicaceae family, is a deciduous, densely branched, and erect shrub. As a leading pioneer tree species in windbreak and sand stabilization, it has played a crucial role in combating desertification in northwestern China. However, different genetic sources of Salix psammophila exhibit significant variations in their effectiveness for windbreak and sand stabilization. Therefore, it is essential to establish a rapid and reliable method for identifying different Salix psammophila varieties. Visible and near-infrared (Vis-NIR) spectroscopy is currently a reliable non-destructive solution for origin traceability. This study introduced a novel feature selection strategy, called qualitative percentile weighted sampling (QPWS), based on the principle of the long tail effect for Vis-NIR spectroscopy. The core idea of QPWS combines weighted sampling and percentage wavelength selection to identify key wavelengths. By employing a multi-threaded parallel execution of multiple QPWS instances, we aimed to search for the optimal feature bands to address the instability issues that can arise during the feature selection process. To address the problem of reduced prediction performance in one-dimensional convolutional neural network (1D-CNN) models after feature selection, we have introduced convolutional autoencoders (CAEs) to reduce the dimensions of wavelengths that are discarded during feature selection. Subsequently, these reduced dimensions are fused with the selected wavelengths, thereby enhancing the model’s performance. With our completed model, we selected outstanding models for model fusion and established a decision system for Salix psammophila. It is worth noting that all 1D-CNN models in this study were developed using Bayesian optimization methods. In comparison with principal component analysis (PCA) and full spectrum methods, QPWS exhibits superior predictive performance in the field of machine learning. In the realm of deep learning, the fusion of data combining QPWS with CAE demonstrated even greater potential with an improvement of average accuracy of approximately 2.13% when compared to QPWS alone and a 228% increase in operational speed compared to a model with full spectra. These results indicated that the combination of CAE with QPWS can be an effective tool for identifying the origin of Salix psammophila.
{"title":"QPWS Feature Selection and CAE Fusion of Visible/Near-Infrared Spectroscopy Data for the Identification of Salix psammophila Origin","authors":"Yicheng Ma, Ying Li, Xinkai Peng, Congyu Chen, Hengkai Li, Xinping Wang, Weilong Wang, Xiaozhen Lan, Jixuan Wang, Zhiyong Pei","doi":"10.3390/f15010006","DOIUrl":"https://doi.org/10.3390/f15010006","url":null,"abstract":"Salix psammophila, classified under the Salicaceae family, is a deciduous, densely branched, and erect shrub. As a leading pioneer tree species in windbreak and sand stabilization, it has played a crucial role in combating desertification in northwestern China. However, different genetic sources of Salix psammophila exhibit significant variations in their effectiveness for windbreak and sand stabilization. Therefore, it is essential to establish a rapid and reliable method for identifying different Salix psammophila varieties. Visible and near-infrared (Vis-NIR) spectroscopy is currently a reliable non-destructive solution for origin traceability. This study introduced a novel feature selection strategy, called qualitative percentile weighted sampling (QPWS), based on the principle of the long tail effect for Vis-NIR spectroscopy. The core idea of QPWS combines weighted sampling and percentage wavelength selection to identify key wavelengths. By employing a multi-threaded parallel execution of multiple QPWS instances, we aimed to search for the optimal feature bands to address the instability issues that can arise during the feature selection process. To address the problem of reduced prediction performance in one-dimensional convolutional neural network (1D-CNN) models after feature selection, we have introduced convolutional autoencoders (CAEs) to reduce the dimensions of wavelengths that are discarded during feature selection. Subsequently, these reduced dimensions are fused with the selected wavelengths, thereby enhancing the model’s performance. With our completed model, we selected outstanding models for model fusion and established a decision system for Salix psammophila. It is worth noting that all 1D-CNN models in this study were developed using Bayesian optimization methods. In comparison with principal component analysis (PCA) and full spectrum methods, QPWS exhibits superior predictive performance in the field of machine learning. In the realm of deep learning, the fusion of data combining QPWS with CAE demonstrated even greater potential with an improvement of average accuracy of approximately 2.13% when compared to QPWS alone and a 228% increase in operational speed compared to a model with full spectra. These results indicated that the combination of CAE with QPWS can be an effective tool for identifying the origin of Salix psammophila.","PeriodicalId":12339,"journal":{"name":"Forests","volume":" 2","pages":""},"PeriodicalIF":2.9,"publicationDate":"2023-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138960720","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}
R. Cerc Korošec, Boštjan Žener, N. Čelan Korošin, M. Humar, Davor Kržišnik, G. Rep, Urška Lavrenčič Štangar
When wood is thermally modified, several chemical reactions take place that change the chemical and physical properties of the wood. These changes correlate with the degree of modification, which is mostly a function of the temperature and duration of modification, and consequently with the mass loss during this process. There is a lack of standardised quality control to verify the degree of heat treatment of wood and thus its quality. One of the possible methods to check the degree of thermal modification of a particular type of wood is thermogravimetry (TG). It is based on the assumption that processes that did not take place during thermal modification continue when the TG experiment is carried out. In this method, calibration curves have to be established based on TG measurements of standard samples that have been thermally modified at different temperatures and whose mass loss during modification is known. The calibration curves show the mass loss during the TG measurement as a function of the mass loss during the previous thermal modification. The course of thermal decomposition during the TG measurements is influenced by many parameters, such as the mass of the sample, the heating rate, the atmosphere in which the measurement takes place, and the shape of the crucible in which the sample is placed. In this paper, the influence of these parameters on the calibration curves was investigated. We have focused on oak wood. The best parameters result in a calibration curve with the largest correlation coefficient R2 and the highest slope of the line k. On this basis, we can determine the mass loss during the thermal modification of unknown samples of the same wood species under the same measurement conditions.
{"title":"Searching for Optimal Measurement Parameters by Thermogravimetry for Determining the Degree of Modification of Thermally Modified Wood","authors":"R. Cerc Korošec, Boštjan Žener, N. Čelan Korošin, M. Humar, Davor Kržišnik, G. Rep, Urška Lavrenčič Štangar","doi":"10.3390/f15010008","DOIUrl":"https://doi.org/10.3390/f15010008","url":null,"abstract":"When wood is thermally modified, several chemical reactions take place that change the chemical and physical properties of the wood. These changes correlate with the degree of modification, which is mostly a function of the temperature and duration of modification, and consequently with the mass loss during this process. There is a lack of standardised quality control to verify the degree of heat treatment of wood and thus its quality. One of the possible methods to check the degree of thermal modification of a particular type of wood is thermogravimetry (TG). It is based on the assumption that processes that did not take place during thermal modification continue when the TG experiment is carried out. In this method, calibration curves have to be established based on TG measurements of standard samples that have been thermally modified at different temperatures and whose mass loss during modification is known. The calibration curves show the mass loss during the TG measurement as a function of the mass loss during the previous thermal modification. The course of thermal decomposition during the TG measurements is influenced by many parameters, such as the mass of the sample, the heating rate, the atmosphere in which the measurement takes place, and the shape of the crucible in which the sample is placed. In this paper, the influence of these parameters on the calibration curves was investigated. We have focused on oak wood. The best parameters result in a calibration curve with the largest correlation coefficient R2 and the highest slope of the line k. On this basis, we can determine the mass loss during the thermal modification of unknown samples of the same wood species under the same measurement conditions.","PeriodicalId":12339,"journal":{"name":"Forests","volume":" 5","pages":""},"PeriodicalIF":2.9,"publicationDate":"2023-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138962451","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}
N. Shephard, Lana L. Narine, Yucheng Peng, Adam Maggard
There are two errors related to units in the original manuscript [...]
原稿中有两处与单位有关的错误[......]
{"title":"Correction: Shephard et al. Climate Smart Forestry in the Southern United States. Forests 2022, 13, 1460","authors":"N. Shephard, Lana L. Narine, Yucheng Peng, Adam Maggard","doi":"10.3390/f14122462","DOIUrl":"https://doi.org/10.3390/f14122462","url":null,"abstract":"There are two errors related to units in the original manuscript [...]","PeriodicalId":12339,"journal":{"name":"Forests","volume":"26 30","pages":""},"PeriodicalIF":2.9,"publicationDate":"2023-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138965824","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}
Xiushan Leng, Di Kong, Zhiwen Gao, Kai Wang, Yu Zhang, Chunyu Li, Hong Liang
The recuperation factors (negative air ion concentration, airborne particulate matter, human comfort index, and acoustic environment index) of coastal green spaces have significant health effects. Most current studies focus on the distribution pattern of single recuperation factors in the forest environment; however, the comprehensive health effects of coastal green spaces are still unknown. To address this, we analyzed the distribution patterns of single and comprehensive health factors in different landscape configurations, landscape compositions, and coastal distances by principal component analysis and systematic clustering. The results show that: (1) coniferous and broadleaf mixed forests exhibit higher integrated health benefits than other landscape compositions; (2) closed and partially closed landscape configurations exhibit enhanced potential for promoting health benefits as opposed to partially open and open spaces; (3) a coastal distance of 150–300 m offers the strongest comprehensive health benefits. These findings collectively suggest that the increased cultivation of closed and partially closed mixed coniferous and broadleaf forest species at a distance of 150–300 m could effectively provide higher comprehensive health effects. Our study complements the ecosystem service of coastal green areas, especially in coastal health ecological services, providing support for coastal rehabilitation landscape planning; and can help to guide tourists in scheduling coastal health activities scientifically.
{"title":"Study on the Comprehensive Health Effects of Coastal Green Areas in Qingdao City, China","authors":"Xiushan Leng, Di Kong, Zhiwen Gao, Kai Wang, Yu Zhang, Chunyu Li, Hong Liang","doi":"10.3390/f14122463","DOIUrl":"https://doi.org/10.3390/f14122463","url":null,"abstract":"The recuperation factors (negative air ion concentration, airborne particulate matter, human comfort index, and acoustic environment index) of coastal green spaces have significant health effects. Most current studies focus on the distribution pattern of single recuperation factors in the forest environment; however, the comprehensive health effects of coastal green spaces are still unknown. To address this, we analyzed the distribution patterns of single and comprehensive health factors in different landscape configurations, landscape compositions, and coastal distances by principal component analysis and systematic clustering. The results show that: (1) coniferous and broadleaf mixed forests exhibit higher integrated health benefits than other landscape compositions; (2) closed and partially closed landscape configurations exhibit enhanced potential for promoting health benefits as opposed to partially open and open spaces; (3) a coastal distance of 150–300 m offers the strongest comprehensive health benefits. These findings collectively suggest that the increased cultivation of closed and partially closed mixed coniferous and broadleaf forest species at a distance of 150–300 m could effectively provide higher comprehensive health effects. Our study complements the ecosystem service of coastal green areas, especially in coastal health ecological services, providing support for coastal rehabilitation landscape planning; and can help to guide tourists in scheduling coastal health activities scientifically.","PeriodicalId":12339,"journal":{"name":"Forests","volume":"11 6","pages":""},"PeriodicalIF":2.9,"publicationDate":"2023-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138995382","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}
Vladislav Soukhovolsky, A. Kovalev, O. Tarasova, Yulia Ivanova
During the growth of a forest insect outbreak epicenter, there are processes that involve the formation and expansion of the primary epicenter of forest damage, as well as secondary epicenters—both connected and unconnected to the primary one. This study characterizes outbreak epicenters in terms of their fractal dimensions and “viscous finger” parameters at the epicenter boundary, highlighting their significance in the context of forest insect management. Local outbreak epicenters were found to be characterized by fractal dimension D = 1.4–1.5, and the boundaries of the epicenters were described using the “viscous finger” model. Proposed models were constructed and validated using remote sensing data obtained from MODIS and Sentinel-2 satellites at epicenter sites and boundaries during the outbreak of the Siberian silk moth Dendrolimus sibiricus Tschetverikov from 2014 to 2020 in the Krasnoyarsk region of Russia. The study revealed that the frequency of the mode spectrum of one-stage spatial series of “viscous fingers” corresponds with the data on the development of the outbreak foci area.
在森林昆虫暴发震源的生长过程中,会有森林损害的主震源以及次震源(与主震源有联系或无联系)的形成和扩展过程。本研究从震中边界的分形维度和 "粘性手指 "参数方面描述了疫情震中的特征,强调了它们在森林昆虫管理方面的意义。研究发现,局部疫情震中的分形维数 D = 1.4-1.5,震中边界采用 "粘性指 "模型进行描述。在俄罗斯克拉斯诺亚尔斯克地区 2014-2020 年西伯利亚蚕蛾 Dendrolimus sibiricus Tschetverikov 爆发期间,利用 MODIS 和 Sentinel-2 卫星获取的震源点和震源边界遥感数据,构建并验证了拟议模型。研究发现,"粘性手指 "单级空间序列的模态频谱频率与疫情病灶区的发展数据相吻合。
{"title":"Forest Insect Outbreak Dynamics: Fractal Properties, Viscous Fingers, and Holographic Principle","authors":"Vladislav Soukhovolsky, A. Kovalev, O. Tarasova, Yulia Ivanova","doi":"10.3390/f14122459","DOIUrl":"https://doi.org/10.3390/f14122459","url":null,"abstract":"During the growth of a forest insect outbreak epicenter, there are processes that involve the formation and expansion of the primary epicenter of forest damage, as well as secondary epicenters—both connected and unconnected to the primary one. This study characterizes outbreak epicenters in terms of their fractal dimensions and “viscous finger” parameters at the epicenter boundary, highlighting their significance in the context of forest insect management. Local outbreak epicenters were found to be characterized by fractal dimension D = 1.4–1.5, and the boundaries of the epicenters were described using the “viscous finger” model. Proposed models were constructed and validated using remote sensing data obtained from MODIS and Sentinel-2 satellites at epicenter sites and boundaries during the outbreak of the Siberian silk moth Dendrolimus sibiricus Tschetverikov from 2014 to 2020 in the Krasnoyarsk region of Russia. The study revealed that the frequency of the mode spectrum of one-stage spatial series of “viscous fingers” corresponds with the data on the development of the outbreak foci area.","PeriodicalId":12339,"journal":{"name":"Forests","volume":" 92","pages":""},"PeriodicalIF":2.9,"publicationDate":"2023-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138995183","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}
In this work, a series of laboratory surface fire experiments were performed over a pine needle fuel bed to investigate the effectiveness of a firebreak and the behaviors of a surface fire across a firebreak. Seven wind velocities of 0~3.0 m/s and six firebreak widths of 10~35 cm are varied. The behaviors of a surface fire across the firebreak, the heat flux received by fuel surface and fuel temperature before and after the firebreak are analyzed and compared simultaneously. The main conclusions are as follows: the behaviors of a surface fire spreading across a firebreak under different wind velocities are classified into three categories—no ignition, ignition by flame contact and ignition by spot fires. When the wind velocity is not more than 1.0 m/s, the surface fire cannot successfully cross the firebreak; as wind velocity changes from 1.5 m/s to 2.5 m/s, the fuel after the firebreak can be ignited by flame contact for relatively narrow firebreak conditions; when the wind velocity increases to 3.0 m/s, the burning fuel can be blown away along the fuel bed, and the fuel behind the firebreak will be ignited by spot fire. A linear relationship between the threshold of firebreak width and the fireline intensity is obtained, and the linear fitting coefficient in this paper is larger than the results reported by Wilson (0.36). For no ignition conditions, the fuel temperature and the heat flux received by the fuel after firebreak are significantly lower than those before the firebreak, whereas their variations over time are similar to those before the firebreak for ignition conditions. Moreover, for no ignition conditions, the maximum fuel temperature and the heat flux after the firebreak increase with wind velocity, but decrease with firebreak width. Additionally, when the fuel temperature (253 °C) and the heat flux received by the fuel considering the radiation and convection (43 kW/m2) after firebreak exceed a threshold value, the surface fire can successfully cross the firebreak.
这项工作在松针燃料层上进行了一系列实验室地表火实验,以研究防火带的有效性和地表火穿过防火带的行为。实验采用了 0~3.0 m/s 的七种风速和 10~35 cm 的六种防火带宽度。同时分析比较了地表火穿越防火带的行为、燃料表面接收的热通量以及防火带前后的燃料温度。主要结论如下:地表火在不同风速下穿过防火带的行为分为三类--无引燃、火焰接触引燃和点火引燃。当风速不大于 1.0 m/s 时,地表火无法成功穿越防火线;当风速从 1.5 m/s 变为 2.5 m/s 时,在防火线相对较窄的条件下,防火线后的燃料可以通过火焰接触点燃;当风速增加到 3.0 m/s 时,燃烧的燃料可以沿着燃料层被吹走,防火线后的燃料将被点燃。防火带宽度临界值与火线强度之间呈线性关系,本文的线性拟合系数大于 Wilson 报告的结果(0.36)。在无着火条件下,防火带后的燃料温度和燃料接收的热通量明显低于防火带前,而在有着火条件下,它们随时间的变化与防火带前相似。此外,在无着火条件下,防火带后燃料的最高温度和热通量随风速的增加而增加,但随防火带宽度的增加而减少。此外,当防火带后的燃料温度(253 °C)和燃料接收的辐射与对流热通量(43 kW/m2)超过临界值时,地表火可以成功穿越防火带。
{"title":"Experimental Analysis on the Behaviors of a Laboratory Surface Fire Spreading across a Firebreak with Different Winds","authors":"Hanwen Guo, Zhengyuan Yang, Ziqun Ye, Dong Xiang, Yunji Gao, Yuchun Zhang","doi":"10.3390/f14122455","DOIUrl":"https://doi.org/10.3390/f14122455","url":null,"abstract":"In this work, a series of laboratory surface fire experiments were performed over a pine needle fuel bed to investigate the effectiveness of a firebreak and the behaviors of a surface fire across a firebreak. Seven wind velocities of 0~3.0 m/s and six firebreak widths of 10~35 cm are varied. The behaviors of a surface fire across the firebreak, the heat flux received by fuel surface and fuel temperature before and after the firebreak are analyzed and compared simultaneously. The main conclusions are as follows: the behaviors of a surface fire spreading across a firebreak under different wind velocities are classified into three categories—no ignition, ignition by flame contact and ignition by spot fires. When the wind velocity is not more than 1.0 m/s, the surface fire cannot successfully cross the firebreak; as wind velocity changes from 1.5 m/s to 2.5 m/s, the fuel after the firebreak can be ignited by flame contact for relatively narrow firebreak conditions; when the wind velocity increases to 3.0 m/s, the burning fuel can be blown away along the fuel bed, and the fuel behind the firebreak will be ignited by spot fire. A linear relationship between the threshold of firebreak width and the fireline intensity is obtained, and the linear fitting coefficient in this paper is larger than the results reported by Wilson (0.36). For no ignition conditions, the fuel temperature and the heat flux received by the fuel after firebreak are significantly lower than those before the firebreak, whereas their variations over time are similar to those before the firebreak for ignition conditions. Moreover, for no ignition conditions, the maximum fuel temperature and the heat flux after the firebreak increase with wind velocity, but decrease with firebreak width. Additionally, when the fuel temperature (253 °C) and the heat flux received by the fuel considering the radiation and convection (43 kW/m2) after firebreak exceed a threshold value, the surface fire can successfully cross the firebreak.","PeriodicalId":12339,"journal":{"name":"Forests","volume":"1 11","pages":""},"PeriodicalIF":2.9,"publicationDate":"2023-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138966483","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}
Global change in the climate is affecting tree/forest growth. There have been many studies that analyzed climate effects on tree growth. Results presented in these studies showed that the climate had both positive and negative effects on tree growth. The nature (positive/negative) and magnitude of the effects and the climate variables affecting growth depended on tree species. Climate-sensitive diameter growth models are not available for white pine (Pinus strobus L.) and white spruce (Picea glauca (Moench) Voss) plantations. These models are needed to project forest growth and yield and develop forest management plans. Therefore, diameter growth models were developed for white pine and white spruce plantations by incorporating climate variables. Four hundred white pine and white spruce trees (200 per species) were sampled from 80 (40 per species) even-aged monospecific plantations (five trees per plantation) across Ontario, Canada. Diameter–age pairs were obtained from these trees using stem analysis. A nonlinear mixed-effects modeling approach was used to develop diameter growth models. To make the models climate sensitive, model parameters were expressed in term of climate variables. Inclusion of climate variables significantly improved model fit statistics and predictive accuracy. For evaluation, diameters (inside bark) at breast height were estimated for three geographic locations (east, west, and south) across Ontario for an 80-year growth period (2021–2100) under three climate change (emissions) scenarios (representative concentration pathway or RCP 2.6, 4.5, and 8.5 watts m−2). For both species, the overall climate effects were negative. For white spruce, the maximum pronounced difference in projected diameters after the 80-year growth period was in the west. At this location, compared to the no climate change scenario, projected spruce diameters under RCPs 2.6 and 8.5 were thinner by 4.64 (15.99%) and 3.72 (12.80%) cm, respectively. For white pine, the maximum difference was in the south. Compared to the no climate change scenario, projected pine diameters at age 80 under RCPs 2.6 and 8.5 at this location were narrower by 4.54 (13.99%) and 7.60 (23.43%) cm, respectively. For both species, climate effects on diameter growth were less evident at other locations. If the values of climate variables are unavailable, models fitted without climate variables can be used to estimate these diameters for both species.
{"title":"Climate-Sensitive Diameter Growth Models for White Spruce and White Pine Plantations","authors":"Mahadev Sharma","doi":"10.3390/f14122457","DOIUrl":"https://doi.org/10.3390/f14122457","url":null,"abstract":"Global change in the climate is affecting tree/forest growth. There have been many studies that analyzed climate effects on tree growth. Results presented in these studies showed that the climate had both positive and negative effects on tree growth. The nature (positive/negative) and magnitude of the effects and the climate variables affecting growth depended on tree species. Climate-sensitive diameter growth models are not available for white pine (Pinus strobus L.) and white spruce (Picea glauca (Moench) Voss) plantations. These models are needed to project forest growth and yield and develop forest management plans. Therefore, diameter growth models were developed for white pine and white spruce plantations by incorporating climate variables. Four hundred white pine and white spruce trees (200 per species) were sampled from 80 (40 per species) even-aged monospecific plantations (five trees per plantation) across Ontario, Canada. Diameter–age pairs were obtained from these trees using stem analysis. A nonlinear mixed-effects modeling approach was used to develop diameter growth models. To make the models climate sensitive, model parameters were expressed in term of climate variables. Inclusion of climate variables significantly improved model fit statistics and predictive accuracy. For evaluation, diameters (inside bark) at breast height were estimated for three geographic locations (east, west, and south) across Ontario for an 80-year growth period (2021–2100) under three climate change (emissions) scenarios (representative concentration pathway or RCP 2.6, 4.5, and 8.5 watts m−2). For both species, the overall climate effects were negative. For white spruce, the maximum pronounced difference in projected diameters after the 80-year growth period was in the west. At this location, compared to the no climate change scenario, projected spruce diameters under RCPs 2.6 and 8.5 were thinner by 4.64 (15.99%) and 3.72 (12.80%) cm, respectively. For white pine, the maximum difference was in the south. Compared to the no climate change scenario, projected pine diameters at age 80 under RCPs 2.6 and 8.5 at this location were narrower by 4.54 (13.99%) and 7.60 (23.43%) cm, respectively. For both species, climate effects on diameter growth were less evident at other locations. If the values of climate variables are unavailable, models fitted without climate variables can be used to estimate these diameters for both species.","PeriodicalId":12339,"journal":{"name":"Forests","volume":"7 20","pages":""},"PeriodicalIF":2.9,"publicationDate":"2023-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138966556","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}
Evaluating the long-term urban forest ecological environmental quality (EEQ) and analyzing the drivers of its spatiotemporal changes can provide a scientific basis for making long-term urban forest planning decisions. Taking into account the characteristics of urban forest parks with low area proportions of construction land and bare land, high vegetation coverage, and serious forest disturbances, we constructed a modified urban forest park EEQ evaluation index based on a remote sensing ecological index named MRSEI, which is composed of the Landsat enhanced vegetation index (EVI), wetness, land surface temperature (LST), and forest disturbance index (FDI). We selected the Nanjing Zijin Mountain National Forest Park as the study area, used landsat time series stack (LTSS) remote sensing images from 1990 to 2020 as the main data source, and adopted the suggested modified MRSEI, the Theil-Sen median method, and the Hurst index to evaluate the EEQ to analyze its spatiotemporal variations and its driving factors in the study area. The main research results were as follows: (1) the EEQ of Zijin Mountain showed an up-and-down, overall slowly increasing trend from 1990 to 2020, while the spatial auto-correlation coefficient showed an overall decreasing trend; (2) the area percentage of the EEQ-persistent region accounted for 78.69%, and the anti-sustainable region accounted for 21.31%; (3) the spatial centers of the EEQ in the study area were mainly concentrated on the middle and upper part of the southern slope of Zijin Mountain, moving southward from 1990 to 2020; (4) the analysis of drivers showed that climate factors, forest landscape structure, forest disturbances, and forest growth conditions were the main driving factors affecting the EEQ in the study area. These results provide a research framework for the analysis of EEQ changes over a long-term period in the urban forest parks of China.
{"title":"Analysis of Eco-Environmental Quality of an Urban Forest Park Using LTSS and Modified RSEI from 1990 to 2020—A Case Study of Zijin Mountain National Forest Park, Nanjing, China","authors":"Fang Ren, Jiaoyang Xu, Yi Wu, Tao Li, Mingyang Li","doi":"10.3390/f14122458","DOIUrl":"https://doi.org/10.3390/f14122458","url":null,"abstract":"Evaluating the long-term urban forest ecological environmental quality (EEQ) and analyzing the drivers of its spatiotemporal changes can provide a scientific basis for making long-term urban forest planning decisions. Taking into account the characteristics of urban forest parks with low area proportions of construction land and bare land, high vegetation coverage, and serious forest disturbances, we constructed a modified urban forest park EEQ evaluation index based on a remote sensing ecological index named MRSEI, which is composed of the Landsat enhanced vegetation index (EVI), wetness, land surface temperature (LST), and forest disturbance index (FDI). We selected the Nanjing Zijin Mountain National Forest Park as the study area, used landsat time series stack (LTSS) remote sensing images from 1990 to 2020 as the main data source, and adopted the suggested modified MRSEI, the Theil-Sen median method, and the Hurst index to evaluate the EEQ to analyze its spatiotemporal variations and its driving factors in the study area. The main research results were as follows: (1) the EEQ of Zijin Mountain showed an up-and-down, overall slowly increasing trend from 1990 to 2020, while the spatial auto-correlation coefficient showed an overall decreasing trend; (2) the area percentage of the EEQ-persistent region accounted for 78.69%, and the anti-sustainable region accounted for 21.31%; (3) the spatial centers of the EEQ in the study area were mainly concentrated on the middle and upper part of the southern slope of Zijin Mountain, moving southward from 1990 to 2020; (4) the analysis of drivers showed that climate factors, forest landscape structure, forest disturbances, and forest growth conditions were the main driving factors affecting the EEQ in the study area. These results provide a research framework for the analysis of EEQ changes over a long-term period in the urban forest parks of China.","PeriodicalId":12339,"journal":{"name":"Forests","volume":"339 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2023-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138966623","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}