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Automated extraction and validation of Stone Pine(Pinus pinea L.)trees from UAV-based digital surface models
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作者 Asli Ozdarici-Ok Ali Ozgun Ok +1 位作者 Mustafa Zeybek Ayhan Atesoglu 《Geo-Spatial Information Science》 CSCD 2024年第1期142-162,共21页
Stone Pine(Pinus pinea L.)is currently the pine species with the highest commercial value with edible seeds.In this respect,this study introduces a new methodology for extracting Stone Pine trees from Digital Surface ... Stone Pine(Pinus pinea L.)is currently the pine species with the highest commercial value with edible seeds.In this respect,this study introduces a new methodology for extracting Stone Pine trees from Digital Surface Models(DSMs)generated through an Unmanned Aerial Vehicle(UAV)mission.We developed a novel enhanced probability map of local maxima that facilitates the computation of the orientation symmetry by means of new probabilistic local minima information.Four test sites are used to evaluate our automated framework within one of the most important Stone Pine forest areas in Antalya,Turkey.A Hand-held Mobile Laser Scanner(HMLS)was utilized to collect the reference point cloud dataset.Our findings confirm that the proposed methodology,which uses a single DSM as an input,secures overall pixel-based and object-based F1-scores of 88.3%and 97.7%,respectively.The overall median Euclidean distance revealed between the automatically extracted stem locations and the manually extracted ones is computed to be 36 cm(less than 4 pixels),demonstrating the effectiveness and robustness of the proposed methodology.Finally,the comparison with the state-of-the-art reveals that the outcomes of the proposed methodology outperform the results of six previous studies in this context. 展开更多
关键词 Stone pine trees Pinus pinea Digital Surface Model(DSM) Unmanned Aerial Vehicle(UAV) enhanced local maxima probabilistic local minima
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STUDY ON THE TREE GROWTH, ARCHITECTURE AND STAND STRUCTURE OF KOREAN PINE PLANTATION
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作者 葛剑平 李传荣 +1 位作者 李平 李景文 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1995年第3期84-88,共5页
The artificial pure and mixed Korean pine (Pinus koraiensis) forests were investigated at Dailing Forestry Bureau in Xiaoxing'an mountains from 1990 to 1992. Depending on the distance between the samplings of Kore... The artificial pure and mixed Korean pine (Pinus koraiensis) forests were investigated at Dailing Forestry Bureau in Xiaoxing'an mountains from 1990 to 1992. Depending on the distance between the samplings of Korean pine and their neighbor trees, the neighbor tree height, the size of neighbor tree canopy, and dimension of neighbor tree. The forest structure was classified into three types: (1) prowth of a tree in the light (open), (2) Growth of a tree in the canopy gap (Gap), (3)Growth of a tree under broad-leaved tree canopy. The frequeney, height, and age of stem divergence of Korean pine tree were investigated by sampling trees. The temporal and spatial model of the tree growth was applied on basis of the height of stem divergence, ratio of height and DBH, and character of tree stem.The morphology and growth character of Korean pine trees during different development stage were forecasted. 展开更多
关键词 Korean pine plantation tree growth model Stand structure
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日本松干蚧的六种寄主松树次生代谢酚类和挥发物成分分析
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作者 王孟筱 张新慰 +7 位作者 任广娟 王静 李洋 曲永赟 马安宝 石磊 段贝宁 武海卫 《应用昆虫学报》 北大核心 2025年第4期989-1000,共12页
【目的】日本松干蚧Matsucoccus matsumurae作为外来入侵害虫,对松林的健康和生态安全构成了严重威胁。本研究旨在探索日本松干蚧不同抗性寄主次生代谢和挥发性物质差异,为今后探索化学生态诱导、寻找环境友好型杀虫剂、开发影响昆虫行... 【目的】日本松干蚧Matsucoccus matsumurae作为外来入侵害虫,对松林的健康和生态安全构成了严重威胁。本研究旨在探索日本松干蚧不同抗性寄主次生代谢和挥发性物质差异,为今后探索化学生态诱导、寻找环境友好型杀虫剂、开发影响昆虫行为的化学信息物质等防控日本松干蚧的应用提供理论依据。【方法】本研究通过靶向代谢物检测和动态顶空进样GC/MS法对6种松树易被日本松干蚧寄生部位的非挥发性次生代谢酚类和挥发性次生代谢有机物的种类和含量进行研究分析。【结果】易被日本松干蚧寄生部位的枝条树皮内的单宁和酚酸,尤其是儿茶素和表儿茶素与树种抗性呈正相关;抗性树种樟子松Pinus sylvestris特有且相对含量大的挥发性有机物有(+)-柠檬烯、莰烯、3-蒈烯和γ-杜松烯,感性树种赤松P. densiflora中相对含量较大的有月桂烯和水芹烯。【结论】儿茶素和表儿茶素可作为判断日本松干蚧抗性树种的指示性指标。(+)-柠檬烯、莰烯、3-蒈烯、γ-杜松烯、月桂烯和水芹烯等不同抗性树种的特异性挥发物是对日本松干蚧具有驱避或引诱效果的化合物。 展开更多
关键词 日本松干蚧 松树 次生代谢物 酚类 挥发物
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基于改进YOLOv5的自然场景下异常变色松树检测方法 被引量:1
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作者 梁青芳 梁超琼 +4 位作者 郭晖 谢毓芬 黄昱 龙韶博 陈鹏 《农业工程学报》 北大核心 2025年第5期165-174,共10页
针对林区松材线虫病异常变色松树零星病枝难以识别、漏检率高、检测速度慢等问题,该研究提出一种基于自适应多尺度特征融合的轻量化目标检测方法。首先,将YOLOv5s的Backbone部分替换为EfficientNetv2-S以压缩模型参数量和计算复杂度,其... 针对林区松材线虫病异常变色松树零星病枝难以识别、漏检率高、检测速度慢等问题,该研究提出一种基于自适应多尺度特征融合的轻量化目标检测方法。首先,将YOLOv5s的Backbone部分替换为EfficientNetv2-S以压缩模型参数量和计算复杂度,其次,添加CBAM(convolution block attention module)注意力模块加强网络对目标病害的关注度,然后,引入加权双向多尺度特征融合网络(bidirectional feature pyramid network,BiFPN)增强不同尺度特征图之间的融合程度,最后采用SIoU(shape intersection over union)损失函数提升模型收敛速度与回归精度。结果显示,改进算法在建模区的精确率、召回率和mAP0.5(IoU阈值为0.5时的平均精度均值)分别达到了92.95%、94.88%和94.21%,比原模型分别提高4.31、5.60和5.13个百分点,参数量、计算量分别为原YOLOv5s的77.07%和35.81%,实现了模型的轻量化;改进模型的帧率和权重文件分别为136.05帧/s和11.90 MB。在未建模区域8、9号样地中变色松树的精确率分别为92.70%、92.60%,枯死松树分别为93.94%、96.83%。在8号样地中枯死松树的召回率达到95.88%。该检测方法适用于自然场景下异常变色松树的快速准确检测,对提高松材线虫病防控智能化水平具有重要现实意义。 展开更多
关键词 松树 图像识别 YOLOv5 EfficientNetv2 CBAM BiFPN 目标检测
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无人机在庐山市枯死松树秋季普查中的应用
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作者 王俞明 周继军 王清 《湖南林业科技》 2025年第2期82-86,共5页
为了掌握庐山市枯死松树发生情况,本次秋季普查应用机动性多旋翼无人机搭载高分辨率专业相机拍摄正射影像图,结合人工核查等技术,对庐山市内15038.53hm^(2)松林进行了全覆盖普查,并利用ArcGIS 10.8、奥维地图等软件标记枯死木坐标点。... 为了掌握庐山市枯死松树发生情况,本次秋季普查应用机动性多旋翼无人机搭载高分辨率专业相机拍摄正射影像图,结合人工核查等技术,对庐山市内15038.53hm^(2)松林进行了全覆盖普查,并利用ArcGIS 10.8、奥维地图等软件标记枯死木坐标点。结果显示:枯死松树发生面积为4078.79hm^(2),同比减少33.25%;小班数量为508个,同比减少34.87%;共标记枯死松树105334株,同比减少49.20%。无人机在本次普查中应用价值巨大,无人机的应用使普查工作更加安全、高效、准确,可以为下一步松材线虫病除治工作的开展提供重要帮助。 展开更多
关键词 庐山市 枯死松树 无人机 秋季普查 松材线虫病
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广东森林松类下木碳含量和热值特征
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作者 张红爱 杨加志 +5 位作者 丁胜 汪求来 黄宁辉 苏晨辉 陈盼 杨志刚 《林业与环境科学》 2025年第2期72-76,共5页
为准确估测森林碳储量和碳汇能力、以及下木的生物质利用提供基本信息,研究采用湿烧法对湛江市廉江市和河源市龙川县松林样地的松类下木(简称松类下木)进行碳含率测定,同时采用氧弹燃烧法对其相应的热值进行了分析。结果显示,龙川县松... 为准确估测森林碳储量和碳汇能力、以及下木的生物质利用提供基本信息,研究采用湿烧法对湛江市廉江市和河源市龙川县松林样地的松类下木(简称松类下木)进行碳含率测定,同时采用氧弹燃烧法对其相应的热值进行了分析。结果显示,龙川县松类下木的碳含率(514.62 g·kg^(-1))显著高于廉江市(497.69 g·kg^(-1))(P<0.05),树干、树根和整株碳含率在不同地域间存在显著差异(P<0.05),树枝、树叶的碳含率差异不显著;不同地域、径阶的松类下木的热值特征差异不显著,树叶的热值最高,树根最低;松类下木的碳含率和热值之间相关性不显著。径阶对热值没有显著影响,可能处于幼龄期的树木尚未完成生理成熟过程,其径向生长与热量转化效率尚未形成显著梯度;是否亚热带比热带更利于松类下木将太阳能转化成化学能,有待于进一步研究。 展开更多
关键词 下木 松类 碳含率 热值
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吉林省汪清林业局国家红松、云杉良种基地建设现状及发展建议
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作者 费晓光 吴蕴洋 +3 位作者 王大宁 李鹏 邵慧忱 程彬 《吉林林业科技》 2025年第2期43-44,48,共3页
本文介绍了吉林省汪清林业局国家红松、云杉林木良种基地的建设现状,针对存在的问题对今后的发展方向提出了建议,为良种基地科学管理和持续发展提供理论和技术支撑,以满足新时期林业发展对林木良种的需求。
关键词 林木良种基地 红松 云杉 建设现状 建议
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基于时间序列的云南松树皮捕食线虫真菌资源调查
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作者 周发平 杨耀权 +2 位作者 张发 佘容 杨晓燕 《四川林业科技》 2025年第1期71-77,共7页
松材线虫病是目前严重威胁全球森林生态系统、传染性极强的松树虫害,筛选高效生防菌株是全世界共同面临的、亟待解决的问题。研究于2023年3月~2024年2月,选取云南大理苍山国家自然保护区的5棵健康云南松进行捕食线虫真菌(nematode-trapp... 松材线虫病是目前严重威胁全球森林生态系统、传染性极强的松树虫害,筛选高效生防菌株是全世界共同面临的、亟待解决的问题。研究于2023年3月~2024年2月,选取云南大理苍山国家自然保护区的5棵健康云南松进行捕食线虫真菌(nematode-trapping fungi,NTF)资源监测。对松树树皮样品进行采集,于实验室内培养、分离纯化NTF,结合形态和分子技术鉴定物种,分析不同高度上(80<高度≤200 cm)、中(20<高度≤80 cm)和下部(0≤高度≤20 cm)树干上NTF群落的时空动态变化。结果显示,松树树皮上存在NTF,Dactylellina属真菌为优势类群,Dactylellina ellipspspora为优势物种(6.07%);在2023年3月检出物种数最多(4种);在2024年2月菌株数最多(11株);NTF检出物种数和菌株数存在时空动态变化。松树土著NTF可作为松材线虫病的高效生防菌株筛选的理想对象。 展开更多
关键词 松材线虫病 树栖捕食线虫真菌 亚隔指孢属Dactylellina 生物防治 生态安全
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基于改进NanoDet-Plus网络的树木小目标病虫害识别
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作者 赵小平 董众祥 +2 位作者 冯瑾霞 闫学龙 胡晶洁 《湖北农业科学》 2025年第2期192-196,共5页
为提高对树木小目标病虫害识别精度,提出一种基于改进NanoDet-Plus网络的小目标病虫害识别方法。为增强对小目标特征的提取能力,通过注意力机制对NanoDet-Plus网络的主干网络进行改进,利用改进NanoDet-Plus网络对松树疫区松材线虫病进... 为提高对树木小目标病虫害识别精度,提出一种基于改进NanoDet-Plus网络的小目标病虫害识别方法。为增强对小目标特征的提取能力,通过注意力机制对NanoDet-Plus网络的主干网络进行改进,利用改进NanoDet-Plus网络对松树疫区松材线虫病进行识别。结果表明,在IOU为0.55时,改进NanoDetPlus网络识别的平均精度达94.51%;在IOU为0.80时,改进NanoDet-Plus网络识别的平均精度为66.57%;在IOU为0.55~0.95时,改进NanoDet-Plus网络识别的平均精度为60.05%。改进NanoDet-Plus网络识别的平均精度均明显高于传统的Faster R-CNN网络、YOLO v6s网络、NanoDet网络、NanoDetPlus网络,且在定位精度和稳定性上的表现最好。由此得出,改进NanoDet-Plus网络具有较好的识别性能,可用于林业病虫害检测,提高防治效率。 展开更多
关键词 改进NanoDet-Plus网络 树木 松材线虫病 小目标 病虫害 识别
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名贵树种白皮松的特质和应用研究
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作者 雷永兴 《林业科技情报》 2025年第1期29-31,共3页
白皮松是松树树种中最具有特质的树种,白皮松在我国有着上千年的栽培历史。白皮松外观呈现翠绿鲜嫩,斑驳的灰绿色在光影的影响之下犹如白龙鳞片,给人一种独特的意境之美,具有重要的观赏价值。分析白皮松的特质以及应用,具有一定的实践... 白皮松是松树树种中最具有特质的树种,白皮松在我国有着上千年的栽培历史。白皮松外观呈现翠绿鲜嫩,斑驳的灰绿色在光影的影响之下犹如白龙鳞片,给人一种独特的意境之美,具有重要的观赏价值。分析白皮松的特质以及应用,具有一定的实践价值。基于此,文章以千阳县国有唐家山林场为例,基于探究臭氧浓度升高状态之下白皮松的生理响应机制,实现对白皮松样的特质评价,为白皮松在城市绿化领域中应用提供了技术支持,以供参考。 展开更多
关键词 名贵树种 白皮松 特质 应用研究
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RADIAL GROWTH OF HUASHAN PINE AND ITS RESPONSE TO CLIMATE 被引量:7
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作者 Shao Xuemei, Wu Xiangding(Institute of Geography, CAS, Beijing 100101 People’s Republic of China)Xi’an Laboratory of Loess and Quaternary Geology, CAS,xi’an 710061 People’s Republic of China) 《Journal of Geographical Sciences》 SCIE CSCD 1994年第Z2期88-102,共15页
Huashan pine (Finus armandii Franch) is a poential species for dendroclimatic study. Ring-width cores were sampled for four stands of two sites from the eastern extreme of the Qinling Mountains. The ring-width chronol... Huashan pine (Finus armandii Franch) is a poential species for dendroclimatic study. Ring-width cores were sampled for four stands of two sites from the eastern extreme of the Qinling Mountains. The ring-width chronologies developed in this study cover a maximum Period from A.D. 1359 t0 1992 and show high common chronology variance over the common period 1911-1960.All the chronologies are significantly correlated with all others, and the degree of correlation appears related to tree age. Response function analyses reveal that from 41 to 75 Percent of chronology variance can be accounted for by monthly mean air temperature and monthly total precipitation. A sufficiently strong correlation of ringwidth index with May and June rainfall and June temperature exists, implying soil moisture to be a limiting factor for Huashan pine growth. The association displayed by response diagrams between narrow rings, low precipitation, and high temperature during spring and early summer indicates a promising potential of ring widths for reconstruction of spring drought for the study area. 展开更多
关键词 tree-ring chronology DENDROCLIMATOLOGY Huashan pine climate-growth relationships
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Temporal changes in nitrogen acquisition of Japanese black pine(Pinus thunbergii) associated with black locust(Robinia pseudoacacia) 被引量:2
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作者 M.L.Lopez C. C.Mizota +2 位作者 Y.Nobori T.Sasaki T.Yamanaka 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第3期585-589,共5页
The alien woody legume, black locust (Robinia pseudoaca-cia), has invaded Japanese black pine (Pinus thunbergii) forests located in Japan’s coastal plain and hill regions where gaps are formed in pine forests aft... The alien woody legume, black locust (Robinia pseudoaca-cia), has invaded Japanese black pine (Pinus thunbergii) forests located in Japan’s coastal plain and hill regions where gaps are formed in pine forests after nematode infestation. Nitrogen fixation by legumes acceler-ates N cycling in forest ecosystems. We studied temporal change in the annual tree-ring resolution N stable isotope composition (δ15N, a per mil deviation of δ15N/14N ratio, relative to atmospheric N2δ15N=0‰) at two natural locations of Japanese black pine forest with black locust that differed in the time since black locust establishment (Shohnai in north-east and Kita-Kyushu in southwest Japan). Analyzed tree-rings covered the period from 1990/1992 to 2009. N acquisition by Japanese black pine from black locust N input to the soil was evidenced by temporal shifting of N stable isotope composition on the annual pine tree rings. With pro-gressive development of the forest stand,δ15N values of earlier tree-ringsδ15N of -5‰) from black pine associated with black locust shifted to-wards values similar to those of black locustδ15N values nearly to-1‰), which suggests acquisition of N by N2 fixation (Shohnai site). In con-trast, in a forest where black locust had settled for two or three genera-tions, in a black pine stand (Kita-Kyushu site), longer periods of N en-richment in the soil were reflected in the elevated tree-ringδ15N values of newly established black pine trees. Based on tree-ringδ15N data from the Shohnai site, we determined that about 10 years after black locust establishment, soil N had already been enriched by black locust N, this, in turn, contributed to N fertilization of surrounding trees in mixed stands. 展开更多
关键词 δ15N natural abundance Japanese black pine black locust nitrogen acquisition tree-RING
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Estimating Pinus palustris tree diameter and stem volume from tree height,crown area and stand-level parameters 被引量:15
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作者 C.A.Gonzalez-Benecke Salvador A.Gezan +3 位作者 Lisa J.Samuelson Wendell P.Cropper Daniel J.Leduc Timothy A.Martin 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第1期43-52,共10页
Accurate and efficient estimation of forest growth and live biomass is a critical element in assessing potential responses to forest management and environmental change. The objective of this study was to develop mode... Accurate and efficient estimation of forest growth and live biomass is a critical element in assessing potential responses to forest management and environmental change. The objective of this study was to develop models to predict longleaf pine tree diameter at breast height (dbh) and merchantable stem volume (V) using data obtained from field measurements. We used longleaf pine tree data from 3,376 planted trees on 127 permanent plots located in the U.S. Gulf Coastal Plain region to fit equations to predict dbh and V as functions of tree height (H) and crown area (CA). Prediction of dbh as a function of H improved when CA was added as an additional independent variable. Similarly, predic- tions of V based on H improved when CA was included. Incorporation of additional stand variables such as age, site index, dominant height, and stand density were also evaluated but resulted in only small improvements in model performance. For model testing we used data from planted and naturally-regenerated trees located inside and outside the geographic area used for model fitting. Our results suggest that the models are a robust alternative for dbh and V estimations when H and CA are known on planted stands with potential for naturally-regenerated stands, across a wide range of ages. We discuss the importance of these models for use with metrics derived from remote sensing data. 展开更多
关键词 Longleaf pine diameter-height relationships crown area individual-tree stem volume growth and yield modeling
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STUDY OF STRUCTURE AND DYNAMICS OF KOREAN PINE FOREST IN THE XIAOXING′AN MOUNTAINS
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作者 葛剑平 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1994年第4期1-5,共5页
The thesis for the Doctorate consist of two parts. The first is to study on structure, dynamics and tree growth of natural Korean pine forest. The second is to research for tree architecture, growth and stand structur... The thesis for the Doctorate consist of two parts. The first is to study on structure, dynamics and tree growth of natural Korean pine forest. The second is to research for tree architecture, growth and stand structure of artificial Korean pine (Pinus koraienstj) forcsts.The thesis comparcs the stand structure, process of regeneratio n, and various tree growth patterns between natural forests and artificial forests. Its purpose is to give a basis for forest management and silviculture. The study was carried out in Liangshui Experimental Forest Farm, which is located in the southern Xiaoxing’an Mountains. 展开更多
关键词 KOREAN pine FOREST tree GROWTH Structure Dynamics
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Life under Supernovae. Story of the Cordillera Pine Forest
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作者 Alexey Ju. Retejum 《Open Journal of Geology》 2019年第8期395-403,共9页
The article presents the first direct evidence of the influence of supernova flashes on the biosphere. Geochemistry and paleontology have not yet provided convincing data on the life response to disasters in the Milky... The article presents the first direct evidence of the influence of supernova flashes on the biosphere. Geochemistry and paleontology have not yet provided convincing data on the life response to disasters in the Milky Way Galaxy. This gap was eliminated through tree ring analysis of bristlecone pine from the Cordilleras responded to seven supernova outbursts in 185-1604 AD. The author used the superposed epoch method to process data at the 11 longest dendrochronologies, based on the results of measurement of annual growth of about 300 trees. The main finding is the growth depression in high-mountain population caused by supernova outbursts lasted for 20 - 30 years after the event. Moreover, in most cases, drastic growth reduction occurred one year prior to the event. In some cases, the annual tree ring increment exceeded the normal range many years after the event, and, consequently, it could be concluded that plant response was associated with the ozone layer depletion. 展开更多
关键词 SUPERNOVA Bristlecone pine trees CORDILLERA Plant Response OZONE Layer Depletion
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Effect of thinning intensity on tree growth and temporal variation of seed and cone production in a Pinus koraiensis plantation
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作者 Thanh Tuan Nguyen Dinh Tien Tai +2 位作者 Peng Zhang Muhammad Razaq Hai-Long Shen 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第3期835-845,共11页
Thinning of Korean pine (Pinus koraiensis Sieb. et Zucc.) is used to facilitate timber and cone production. The present study in Northeast China investigated the effects of thinning intensity on individual tree growth... Thinning of Korean pine (Pinus koraiensis Sieb. et Zucc.) is used to facilitate timber and cone production. The present study in Northeast China investigated the effects of thinning intensity on individual tree growth, temporal variation in cone yield, and seed quality in Korean pine plantation. In 2005, five thinning intensity levels (none, extreme, heavy, moderate and light) were set in 15 permanent plots in a 32-year-old Korean pine plantation at Mengjiagang Forest Farm, Jiamusi City, Heilongjiang Province. We recorded tree growth and seed cone production from 2013 to 2016, i.e., from 8 to 11 years after thinning. Except for height growth, thinning increased tree growth (diameter at breast height and crown size) and improved cone yield. The extreme thinning treatment (to 300 trees per hectare) resulted in the largest tree diameter, tree volume, crown size and 4-year cone production per tree. The highest cone yield per tree in the mast year (2014) was observed when stands were thinned to 500 trees per hectare (heavy thinning). Although the best cone and seed quality and the largest cone and seed mass per tree were recorded in the heavily thinned stand, no significant differences were found between heavy and moderate thinning stands (750 trees per hectare). At the stand level, the moderately thinned stand had the highest basal area, stock volume and seed cone production per stand. Our results suggest that thinning to 750 trees per hectare will improve timber and cone productivity in 40-year-old P. koraiensis stands. 展开更多
关键词 Korean pine Thinning intensity SEED YIELD tree GROWTH Temporal VARIATION in CONE YIELD
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Ponderosa Pine Family Growth Comparisons in the Central Great Plains of Kansas
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作者 Wayne A. Geye Keith D. Lynch 《Open Journal of Forestry》 2011年第2期27-30,共4页
Ponderosa pine (Pinus ponderosa Laws.) has been planted widely in the Great Plains. Recommendations based on a 1968 study were to use material from south central South Dakota and north central Nebraska. A second test ... Ponderosa pine (Pinus ponderosa Laws.) has been planted widely in the Great Plains. Recommendations based on a 1968 study were to use material from south central South Dakota and north central Nebraska. A second test to further delineate seed sources (provenance/families) in this region was established in 1986. This paper reports results for survival, height, diameter, and D2H measurements in Kansas at 15 years. Results identify a wide range of suitable families within the Great Plains region.A majority of the tested sources performed well especially those from central Nebraska. Those sources from eastern Montana and western Nebraska performed poorly where environmental or geographic conditions were the poorest, thus verifying the original recommendations. 展开更多
关键词 PONDEROSA pine PINUS PONDEROSA PROVENANCE Seed Sources tree Selection GROWTH Characteristics.
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Simulation of the biomass dynamics of Masson pine forest under different management
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作者 ZHANG Gui-lian WANG Kai-yun +1 位作者 LIU Xin-wei PENG Shao-lin 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第4期305-311,共7页
TREE submodel affiliated with TREEDYN was used to simulate biomass dynamics of Masson pine (Pinus massoniana) forest under different managements (including thinning, clear cutting, combining thinning with clear cut... TREE submodel affiliated with TREEDYN was used to simulate biomass dynamics of Masson pine (Pinus massoniana) forest under different managements (including thinning, clear cutting, combining thinning with clear cutting). The purpose was to represent biomass dynamics involved in its development, which can provide scientific arguments for management of Masson pine forest. The results showed the scenario that 10% or 20% of biomass of the previous year was thinned every five years from 15 to 40 years made total biomass of pine forest increase slowly and it took more time to reach a mature community; If clear cutting and thinning were combined, the case C (clear cutting at 20 years of forest age, thinning 50% of remaining biomass at 30 years of forest age, and thinning 50% of remaining biomass again at 40 years of forest age) was the best scenario which can accelerate speed of development of Masson pine forest and gained better economic values. 展开更多
关键词 tree submodel BIOMASS Rate of nitrogen uptake Dinghushan Masson pine forest
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阔叶红松林林木与林分生长对采伐干扰的响应 被引量:5
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作者 岳庆敏 何怀江 +2 位作者 张春雨 赵秀海 郝珉辉 《生态学报》 CAS CSCD 北大核心 2024年第5期2019-2028,共10页
提升森林质量、修复生态功能是东北阔叶红松林生态修复的核心,而阐明林木与林分生长对采伐干扰的响应机理是其中的关键。森林对采伐干扰的响应会受到空间尺度、时间尺度以及干扰程度等因素的综合影响。以往的研究侧重于比较不同采伐处... 提升森林质量、修复生态功能是东北阔叶红松林生态修复的核心,而阐明林木与林分生长对采伐干扰的响应机理是其中的关键。森林对采伐干扰的响应会受到空间尺度、时间尺度以及干扰程度等因素的综合影响。以往的研究侧重于比较不同采伐处理下林木生长的相对大小,而忽视了不同恢复时间下,林木和林分生长随干扰程度的变化。以吉林蛟河阔叶红松林采伐样地为对象,基于连续四次样地调查数据(2011、2013、2015、2018年),分别探讨了林木和林分生长在不同恢复阶段对不同程度采伐干扰的响应,并通过构建分段模型确定采伐干扰阈值。结果显示:林木和林分生长对采伐干扰的响应并不一致,采伐促进了林木生长,并且林木生长量随采伐强度的升高而升高;采伐降低了林分生产力,林分生产力随采伐强度的升高而降低。林木和林分生长对采伐干扰的响应存在时滞效应:林木和林分生长在采伐后两年内并无显著变化,而在采伐三年后才发生明显变化。此外,分段模型的结果显示:当保留木断面积为21.6 m^(2)/hm^(2)时,林分生产力最高,表明通过密度调整使阔叶红松林胸高断面积维持在21.6 m^(2)/hm^(2)附近,可使林分处于较高的生产力水平、促进森林恢复。研究结果能够为制定科学的阔叶红松林生态修复策略提供技术支撑。 展开更多
关键词 阔叶红松林 采伐干扰 林木生长 林分生产力 采伐强度
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树干注药技术的基本原理与应用 被引量:5
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作者 李东振 马健 +3 位作者 马帅 理永霞 杨灿 张星耀 《中国森林病虫》 北大核心 2024年第4期28-35,共8页
树干注药技术具有施用精准、药物利用率高、接触风险低和环境污染少等优点。当喷洒和灌根施药等手段难以发挥作用或对环境造成污染时,树干注药是更为合适的手段,其开发和应用已引起国内外广泛关注。概述树干注药技术的树木生理学原理和... 树干注药技术具有施用精准、药物利用率高、接触风险低和环境污染少等优点。当喷洒和灌根施药等手段难以发挥作用或对环境造成污染时,树干注药是更为合适的手段,其开发和应用已引起国内外广泛关注。概述树干注药技术的树木生理学原理和影响树干注药的因素,系统介绍国内外无压力注射、打孔压力注射和微孔压力注射的技术设备和特点,以及树干注药技术在防治松材线虫病等病虫害中的应用,旨在为树干注药技术的发展和优化提供参考。 展开更多
关键词 松材线虫病 树干注药 森林保护 树木健康
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