通讯机构：
[Lv, Y ] C;Cent South Univ Forestry & Technol, Fac Forestry, Changsha 410004, Peoples R China.;Key Lab Natl Forestry & Grassland Adm Forest Resou, Changsha 410004, Peoples R China.;Cent South Univ Forestry & Technol, Res Ctr Forestry Remote Sensing & Informat Engn, Changsha 410004, Peoples R China.
关键词：
crown size;neighborhood effects;competition index;tree species diversity;tree growth
摘要：
Competition among trees for limited resources (e.g., sunlight, water, and nutrients) impacts their growth differently. Crown plays a crucial role in resource access for trees. However, uncertainties persist regarding crown size differences, tree growth, and tree competition levels between coniferous and broadleaf trees in mixed-age forests. We conducted a study on 3008 live trees across 28 plots in Hunan Province to measure individual crown size and tree growth increment. Introducing a new metric, the Crown Size Competition Index (CSCI), we assessed competition pressure among coniferous and broadleaf species in mixed-age forests. We examined the correlation between competition indices and tree growth increment while also investigating the influence of neighboring species diversity on tree competition. Our results revealed a significant negative correlation between the tree growth of Cunninghamia lanceolata (Lamb.) Hook.(CL) and Phoebe bournei (Hemsl.) Yang (PB) and the competition index. Increased competitive pressure on the focal tree corresponded to a decline in the growth of focal tree volume, with a more pronounced impact observed in PB compared to CL. The diversity of neighboring species contributed to variations in competition for the focal tree, with broadleaved species (PB) exerting a greater influence on the focal tree than coniferous species (CL). These findings underscore the competitive potential of PB in mature coniferous stands and advocate for the restoration of stratified mixes in CL broadleaf forests. Furthermore, our findings support the management strategies for the valuable tree species PB.
期刊：
FRONTIERS IN ECOLOGY AND EVOLUTION,2023年11:1085272 ISSN：2296-701X
通讯作者：
Li, JP
作者机构：
[Tang, Tao; Li, Jiping] Cent South Univ Forestry & Technol, Fac Forestry, Changsha, Peoples R China.;[Tang, Tao; Li, Jiping] Cent South Univ Forestry & Technol, Key Lab State Forestry Adm Forest Resources Manage, Changsha, Peoples R China.;[Tang, Tao; Li, Jiping] Cent South Univ Forestry & Technol, Key Lab Forestry Remote Sensing Based Big Data & E, Changsha, Peoples R China.;[Tang, Tao; Li, Jiping] Cent South Univ Forestry & Technol, Res Ctr Forest Remote Sensing & Informat Engn, Changsha, Peoples R China.;[Velazquez, Javier] Univ Catolica Avila, Dept Environm & Agroforestry, Avila, Spain.
通讯机构：
[Li, JP ] ;Cent South Univ Forestry & Technol, Fac Forestry, Changsha, Peoples R China.;Cent South Univ Forestry & Technol, Key Lab State Forestry Adm Forest Resources Manage, Changsha, Peoples R China.;Cent South Univ Forestry & Technol, Key Lab Forestry Remote Sensing Based Big Data & E, Changsha, Peoples R China.;Cent South Univ Forestry & Technol, Res Ctr Forest Remote Sensing & Informat Engn, Changsha, Peoples R China.
摘要：
<jats:p>The reduction and fragmentation of forests due to human activities are two primary factors that have led to forest biodiversity losses. The lack of forest continuation may prevent organisms from escaping areas that are no longer habitable due to altered environmental conditions and the reduction in size of habitat regions. Therefore, protecting and promoting forest connectivity has become one of the important objectives of forest management. The forests were regarded as independent elements, and the connectivity of the forest itself was directly evaluated in previous studies. However, this approach ignores the maintenance of forest connectivity, while requiring the participation of other landscape elements. In this study, we indirectly determine the forest priority by evaluating the landscape priority by integrating analysis with the habitat suitability (HS) model, MSPA and and <jats:inline-formula><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" id="im1"><mml:mrow><mml:mi>B</mml:mi><mml:msubsup><mml:mi>C</mml:mi><mml:mtext>k</mml:mtext><mml:mrow><mml:mi>P</mml:mi><mml:mi>C</mml:mi></mml:mrow></mml:msubsup></mml:mrow></mml:math></jats:inline-formula> and <jats:inline-formula><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" id="im2"><mml:mrow><mml:mtext>d</mml:mtext><mml:mi>P</mml:mi><mml:msub><mml:mi>C</mml:mi><mml:mi>k</mml:mi></mml:msub></mml:mrow></mml:math></jats:inline-formula> index. We studied the wild boar (<jats:italic>Sus scrofa</jats:italic>) habitats in and around Hupingshan and Houhe National Nature Reserves to illustrate the indirect evaluation method of forest priority. The results showed that forests with high priority, medium priority, low priority, and non-priority comprised 596, 64, 58 and 105 km<jats:sup>2</jats:sup>, respectively, accounting for the 41.2, 2.7, 3.0, and 11.9% of the total forest area. Our research revealed that evaluating the forest priority by analysing the landscape priority was an effective method for forest priority identification, and this strategy can be used to other regions or species for the goal of identifying the forest priority for biodiversity conservation.</jats:p>
作者机构：
[Wang, Yiru; Tang, Tao; Liu, Zhaohua; Li, Jiping] Cent South Univ Forestry & Technol, Fac Forestry, Changsha 410004, Peoples R China.;[Wang, Yiru; Tang, Tao; Liu, Zhaohua; Li, Jiping] Key Lab State Forestry Adm Forest Resources Manage, Changsha 410004, Peoples R China.;[Wang, Yiru; Tang, Tao; Liu, Zhaohua; Li, Jiping] Cent South Univ Forestry & Technol, Res Ctr Forest Remote Sensing & Informat Engn, Changsha 410004, Peoples R China.
通讯机构：
[Tao Tang; Jiping Li] A;Authors to whom correspondence should be addressed.<&wdkj&>Research Centre of Forest Remote Sensing and Information Engineering, Central South University of Forestry and Technology, Changsha 410004, China<&wdkj&>Key Laboratory of State Forestry Administration on Forest Resources Management and Monitoring in Southern Area, Changsha 410004, China<&wdkj&>Faculty of Forestry, Central South University of Forestry and Technology, Changsha 410004, China
关键词：
stand structure;site conditions;forest functions;structural equation model;Cunninghamia lanceolata;Phoebe bournei
摘要：
Forest stand structure (the characteristics and interrelationships of live trees) and site conditions (the physical and environmental characteristics of a specific location) have been linked to forest regeneration, nutrient cycling, wildlife habitat, and climate regulation. While the effects of stand structure (i.e., spatial and non-spatial) and site conditions on the single function of Cunninghamia lanceolata and Phoebe bournei (CLPB) mixed forest have been studied in previous studies, the relative importance of stand structure and site conditions in terms of productivity, species diversity, and carbon sequestration remains unresolved. In this study, a structural equation model (SEM) was adopted to analyze the relative importance of stand structure and site conditions for the forest productivity, species diversity, and carbon sequestration of CLPB mixed forest in Jindong Forestry in Hunan Province. Our research demonstrates that site conditions have a greater influence on forest functions than stand structure, and that non-spatial structures have a greater overall impact on forest functions than spatial structures. Specifically, the intensity of the influence of site conditions and non-spatial structure on functions is greatest for productivity, followed by carbon sequestration and species diversity. In contrast, the intensity of the influence of spatial structure on functions is greatest for carbon sequestration, followed by species diversity and productivity. These findings provide valuable insights for the management of CLPB mixed forest in Jindong Forestry and have significant reference value for the close-to-natural forest management (CTNFM) of pure Cunninghamia lanceolata forests.
作者机构：
[Xie, Zhengchang; Cao, Xiaoyu; Zhao, Wenfei; Li, Jiping; Sun, Yaping] Cent South Univ Forestry & Technol, Fac Forestry, Changsha 410004, Peoples R China.;[Cao, Xiaoyu; Li, Jiping] Key Lab State Forestry Adm Forest Resources Manage, Changsha 410004, Peoples R China.;[Peng, Yuanying] Lewis Univ, Coll Arts & Sci, Romeoville, IL 60446 USA.
通讯机构：
[Xiaoyu Cao; Yuanying Peng] A;Authors to whom correspondence should be addressed.<&wdkj&>College of Arts and Sciences, Lewis University, Romeoville, IL 60446, USA<&wdkj&>Authors to whom correspondence should be addressed.<&wdkj&>Key Laboratory of State Forestry Administration on Forest Resources Management and Monitoring in Southern Area, Changsha 410004, China<&wdkj&>Faculty of Forestry, Central South University of Forestry and Technology, Changsha 410004, China
关键词：
age groups;soil depth;Chinese fir plantation;model;soil nutrients;soil fertility index
摘要：
Understanding nutrient quantity and quality in forest soils is important for sustainable management of forest resources and maintaining forest ecosystem services. In this study, six soil nutrient indicators, including soil organic matter (SOM), total nitrogen (TN), total phosphorus (TP), available nitrogen (AN), available phosphorus (AP), and available potassium (AK) were measured in five different aged stands of Chinese fir forests in subtropical China. A structural equation model (SEM) was developed based on these soil nutrients indicators in order to better evaluate the soil fertility index (SFI) in these studied forests. The results show that soil nutrient contents changed with the soil depth in different age groups. The SOM decreased in a specific order: over mature > mature > near mature > middle > young stands. The TN content of the soil gradually decreased with increased soil depth throughout all age groups. The SEM indicated that the TN had the highest weight of 0.4154, while the TP had the lowest weight at 0.1991 for estimating the SFI. The weights of other indicators (AN, SOM, AP, and AK) ranged 0.2138-0.3855 in our study. The established SEM satisfied the fitness reference values and was able to accurately describe the forest soil nutrient status through the SFI. The overall SFI values were significantly higher in over mature stands than in young-aged stands and in topsoil than in deeper soil in all examined forests. Soil TN, AP, and AK were the most important nutrient indicators to the evaluation of the SFI in the study sites. The results confirmed that the SEM was suitable to estimate the weights of the SFI and better describe the soil nutrient status in forests. Our research provides an innovative approach to assess a soil nutrient status and soil fertility and provides a scientific basis for accurate implementation of soil nutrient assessment in forest ecosystems.
作者机构：
[Wang, Yiru; Cao, Xiaoyu; Lv, Y; Lv, Yong; Liu, Zhaohua; Li, Jiping] Cent South Univ Forestry & Technol, Fac Forestry, Changsha 410004, Peoples R China.;[Wang, Yiru; Cao, Xiaoyu; Lv, Y; Lv, Yong; Liu, Zhaohua; Li, Jiping] Key Lab State Forestry Adm Forest Resources Manage, Changsha 410004, Peoples R China.;[Wang, Yiru; Cao, Xiaoyu; Lv, Y; Lv, Yong; Liu, Zhaohua; Li, Jiping] Cent South Univ Forestry & Technol, Res Ctr Forest Remote Sensing & Informat Engn, Changsha 410004, Peoples R China.;[Liu, Zhaohua] Key Lab Forestry Remote Sensing Based Big Data & E, Changsha 410004, Peoples R China.
通讯机构：
[Lv, Y ] C;Cent South Univ Forestry & Technol, Fac Forestry, Changsha 410004, Peoples R China.;Key Lab State Forestry Adm Forest Resources Manage, Changsha 410004, Peoples R China.;Cent South Univ Forestry & Technol, Res Ctr Forest Remote Sensing & Informat Engn, Changsha 410004, Peoples R China.
关键词：
stand spatial structure;tree size;multivariate distribution;cunninghamia lanceolata;phoebe bournei;structure optimization
摘要：
<jats:p>The spatial structure of forest stands significantly influences inter-tree competition and the overall stability of the stand’s ecological dynamics, and a profound understanding of forest stand spatial structure is essential for both effective forest management and ecological research. Previous studies on spatial structure have primarily employed single variables, offering only one-dimensional structural insights and lacking the capacity to interpret multidimensional information. In light of these limitations, our study introduces a novel approach founded on a six-variable distribution, aimed at conducting a comprehensive analysis and interpretation of the spatial attributes of forest stands. Diverging from conventional univariate or bivariate methods, the hexi-variate approach simultaneously considers six variables, facilitating a more intricate exploration of the intricate interrelationships within forest ecosystems from six distinct dimensions. We conducted an in-depth analysis of the spatial structural attributes within the forest stand, encompassing factors such as species diversity, size variation, spatial distribution patterns, openness, vertical stratification, and stand competition. To capture a comprehensive view of the trees’ spatial information, we employed the hexadecimal distribution method, effectively quantifying their characteristics across six dimensions. Our study unveiled a significant correlation between spatial structure and stand growth, establishing a connection by integrating the spatial structure with key structural features relevant to tree size. The outcomes of this study shed light on the effectiveness and superiority of the six-element distribution method when it comes to the analysis of forest structural characteristics. Our approach offers valuable insights into the optimization of forest management strategies, encompassing selective harvesting and biodiversity conservation, thereby establishing a solid footing for sustainable forest management practices.</jats:p>
作者机构：
[Wang, Danmei; Tang, Tao; Li, Jiping] Cent South Univ Forestry & Technol, Fac Forestry, Changsha 410004, Peoples R China.
通讯机构：
Faculty of Forestry, Central South University of Forestry and Technology, Changsha, China
关键词：
Close-to-nature management;Objective forest shape;Optimal stand density;Phoebe bournei plantation;Sustainable forest management;Target tree density
期刊：
Science of The Total Environment,2021年774:145067 ISSN：0048-9697
通讯作者：
Li, Jiping(lijiping1602@163.com)
作者机构：
[Tang, Tao; Li, Jiping; Sun, Hua] Cent South Univ Forestry & Technol, Fac Forestry, 498 Southern Shaoshan Rd, Changsha 410004, Hunan, Peoples R China.;[Tang, Tao; Li, Jiping; Sun, Hua] State Forestry Adm Forest Resources Management &, Key Lab, Changsha 410004, Peoples R China.;[Sun, Hua] Key Lab Forestry Remote Sensing Based Big Data &, Changsha 410004, Peoples R China.;[Sun, Hua] Cent South Univ Forestry & Technol, Res Ctr Forest Remote Sensing & Informat Engn, Changsha 410004, Peoples R China.;[Deng, Chao] Forestry Bur Changde City Hunan Prov, Changde 415099, Peoples R China.
通讯机构：
[Jiping Li] F;Faculty of Forestry, Central South University of Forestry and Technology, Changsha 410004, Hunan Province, China<&wdkj&>Key Laboratory of State Forestry Administration on Forest Resources Management and Monitoring in Southern Area, Changsha 410004, China
摘要：
The decline and fragmentation of habitats areas are two main factors that lead to the reduction of biodiversity in landscape ecosystems. As a kind of large carnivores, South China tiger (Panthera tigris amoyensis) is one of the most endangered tiger subspecies and considered to be extinct in the wild. The Chinese government has intended to release a certain number of tigers into two of their historically habitats areas, Hupingshan-Houhe national nature reserves (NNR) in central-south China that provides suitable habitats for P. tigris. Because wild boar (Sus scrofa) is a prey of P. tigris, spatially characterizing the populations of the prey and its habitats is critical for the success of habituating the tigers to the areas. Although there has been effort made to protect the habitats of wild boar, there have been no report that deal with investigation and analysis of the habitat suitability and potential forwild boar, especially in terms of landscape connectivity. Herewe present the novel integration of the habitat suitability index (HSI) and graph-based network to identify the priority areas for wild boar dispersal in and around the NNR. In addition, a novel method to identify the proper connectivity distance to avoid excessive connectivity when the field data are essentially non-existent. Results showed that in summer andwinter, the potential habitat areas were 6848-10,245 and 5984-10,152km(2), respectively. The total area of the priority patches was 1590 km(2), approximately occupying 16% of the suitable habitat area. Our study indicated that the novel integration of the HSI and network analysis led to an effective approach to spatially characterize priority patches to support decision-making for landscape planning. The results shown here also have implications for future efforts for habituating large carnivores into their historical habitat regions. (c) 2021 Elsevier B.V. All rights reserved.
作者机构：
[委霞; 赵文菲; 曹小玉; 李际平] College Forestry, Central South University of Forestry and Technology, Key Laboratory of State Forestry and Grassland Administration on Forest Resources Management and Monitoring in Southern Area, Changsha, 410004, China
