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Journal of Forestry Research 2017年第5期28卷 1007-1018页

作者： Do-Hyun Kim Sung-Jun Na Sea-Hyun Kim Ewane Basil Ewane Dae-Bong Kang Do-Hyung Lee Department of Forest Resources Yeungnam University Department of Forest Genetic Resources National Institute of Forest Science

We estimated the growth volume of artificially reforested pinus densiflora in a post-fire area on three different contour conditions by comparing and analyzing the vertical and horizontal distributions of below-ground roots on each contour. The main roots at the south-facing slope (SS) developed in a long and straight form, and those on the north-facing slope (NS) in a twisted form. The side roots developed more than the main roots on the Ridge. The depth of taproots decreased in the following order: SS?>?NS?>?Ridge. The roots on the SS developed in a pile-form root structure whereas those in the Ridge and NS developed concentrically near the root collar. The amount of root development decreased in the following order: SS?>?NS?>?Ridge. The ratio of fine roots from the whole-root development decreased in the following order: Ridge?>?SS?>?NS. These results can guide considerations of growth differences according to the planting contour conditions for future establishment of P. densiflora artificial plantations.

关键词： pinus densiflora Growth characteristics Contour conditions Post-fire plantation Wildfire Restoration Soil depth

Decomposition dynamics and ecological stoichiometry of Quercus acutissima and pinus densiflora litter in the Grain to Green Program Area of northern China

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Journal of Forestry Research 2020年第5期31卷 1613-1623页

作者： Jianni Sun Peng Gao Haidong Xu Cheng Li Xiang Niu Forestry College Mountain Tai Forest Ecosystem Research Station of State Forestry AdministrationShandong Provincial Key Laboratory of Soil Erosion and Ecological RestorationShandong Agricultural UniversityTai’an 271018ShandongPeople’s Republic of China Research Institute of Forest Ecology Environment and ProtectionChinese Academy of ForestryBeijing Collaborative Innovation Center for Eco-Environmental Improvement With Forestry and Fruit TreesBeijing 100091People’s Republic of China

Litter decomposition and ecological stoichiometry of nutrient release is an important part of material cycling and energy flow in forest ecosystems.In a study of the ecological stoichiometry and nutrient release during litter decomposition in a pine–oak forest ecosystem of the Grain to Green Program(GTGP)area of northern China,a typical pine and oak species(PDS:pinus densiflora Sieb.,QAC:Quercus acutissima Carr.)were selected in the Taiyi Mountain study area.The ecological stoichiometry characteristics of carbon(C),nitrogen(N)and phosphorus(P)and litter decomposition dynamics were studied by field sampling and quantitative analyses.The results showed the following.(1)The decomposition dynamics of both litters was slow-fast-slow.The most important climatic factor affecting the litter decomposition rate from May to October was precipitation and temperature from November to April of the following year.(2)Throughout the 300-day study,in both litters,C of the two litters was released,N first accumulated and was then released,and P exhibited a release-accumulate-release pattern.(3)C:P was significantly higher than C:N and N:P(p<0.05);the C:N of PSD litter was higher than that of QAC(p<0.05),but the N:P of QAC litter was higher than that of PSD litter(p<0.05).The C:N of both litters was very high in the study area,indicating that the nutrient release ability during litter decomposition in the two typical pine–oak forest ecosystems was relatively weak;therefore,more attention should be paid to nitrogen-fixing species and mixed forests in the GTGP area of northern China.

关键词： Decomposition dynamics Ecological stoichiometry Litter pinus densiflora Quercus acutissima Grain to Green Program(GTGP)

Effect of stand density and humus removal on regeneration of pinus densiflora seedlings in a mixed conifer and broad-leaved forest

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Forestry Studies in China 2012年第2期14卷 85-91页

作者： WUChu-ping MakotoAND0 ZHANGJun SHENAi．hua YUANWei-gao ZHUJin—ru JIANGB0 ZhejiangForestryAcademy Hangzhou310023PR．China FieldScienceEducationandResearchCenter KyotoUniversityKitashirakawa—oiwakeKyoto6068502Japan

We studied the impact of stand density and forest floor humus removal on regeneration ofpinus densiflora in a mixed co- nifer and broad-leaved forest on the Daimonji-Yama Mountain, Kyoto, Japan. Three levels of stand density were set, i.e., a clear-cut site, a heavily thinned site and a lightly thinned site. In each density treatment, comparisons were carried out between humus removal （A0-free） and humus intact （A0-intact） subplots. We counted the emergence of sown pine seeds and measured survival and growth of pine seedlings over the next four years. In addition, light conditions and the recovery of understory were monitored. Results show that thinning intensity and humus removal promoted the establishment and growth of seedlings. One exception, however, was that seedling growth was minimal in the heavily thinned A0-intact subplots. This was due to a strong response of understory vegetation growth on the treatment combination, which hindered the pine seedling growth. Furthermore, we found that the canopy openness measured at 1.3-m height remained at least 35% for the heavily thinned site in 2008. The results suggest that the removal of the A0 layer after heavy thinning is the most effective and labor-saving operation for P. densifiora regeneration.

关键词： pinus densiflora regeneration understory vegetation thinning forest operation

Study on the Practical and Ideal Mature Age of pinus densiflora

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Agricultural Biotechnology 2020年第1期9卷 67-69页

作者： Aidong WANG Fengzhen WANG Dongmei YUE Jing ZHANG Dequan ZHANG Lingfei YU Qing ZHAO Shandong Forestry Monitoring and Planning Institute

This study was conducted on the analytic tree and got the fitting empirical equation of tree growth, in which the tree growth rate was used as the variable and time as the independent variable. The arithmetical operation to the function got the mature age of tree growth, and the practical and ideal mature ages of pinus densiflora were 58 and 123.5 a, respectively. In addition, the application research direction and matters needing attention were proposed.

关键词： pinus densiflora Mature age Empirical equation Analytic tree

北方砂石山2种常见灌木对刺槐、赤松纯林生长胁迫性

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林业科技通讯 2023年第4期 86-90页

作者：孔令雷马胜国徐军杨从从赵冬曲阜市自然资源和规划局山东曲阜273100 山东省林业保护和发展服务中心曲阜市气象局

为研究北方砂石山构树(Broussonetia papyrifera)、黄荆(Vitex negundo)与刺槐(Robinia pseudoacacia)、赤松(pinus densiflora)纯林共生期间的种间制约关系,探索对刺槐过熟林更新、赤松林复壮的最佳方法,选取了曲阜市国有石门寺林场有... 详细信息

为研究北方砂石山构树(Broussonetia papyrifera)、黄荆(Vitex negundo)与刺槐(Robinia pseudoacacia)、赤松(pinus densiflora)纯林共生期间的种间制约关系,探索对刺槐过熟林更新、赤松林复壮的最佳方法,选取了曲阜市国有石门寺林场有代表性的刺槐、赤松纯林为研究对象。研究结果表明,49年树龄刺槐、赤松林截至2020年,活立木保有量分别为28株/667m^(2)、40株/667m^(2),死亡率为2000年活立木保有量的74.5%、38.5%,同比增长36%、7.7%,通过样本相关系数的计算公式得出,构树、黄荆与刺槐、赤松纯林树高、冠幅生长量成显著负相关关系。2000年林分出现“天窗”后,通过天然下种林下植物群落逐渐形成,由于构树、黄荆极强的适应性对刺槐、赤松生长形成了很强的胁迫性,加剧了乔灌种间土壤水分恶性竞争,进一步加快了刺槐、赤松死亡速度。

关键词：北方砂石山刺槐 Robinia pseudoacacia 赤松 pinus densiflora 乔灌共生生长胁迫

Pathogenicity of aseptic Bursaphelenchus xylophilus

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Pathogenicity of aseptic Bursaphelenchus xylophilus