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2018年3—4月份,在广西南丹县地理位置毗邻、立地条件相似的区域,以9、17、25、37年生秃杉(Taiwania flousiana)林为研究对象,在不同林龄的秃杉人工林中分别设置3个样地(20 m×30 m),测定样地林冠郁闭度、林分密度,林木胸径、树高、冠幅、枝下高等;在每个林龄阶段样地外选择3株平均木并伐倒,分别测定树叶、树枝、干皮、干材、根系鲜质量,并按灌木层、草本层、凋落物层测定生物...
以关帝山华北落叶松林为研究对象,采用典型抽样方法,调查其林分密度、平均树高、平均胸径、平均冠幅、平均林龄和平均枝下高6个林分因子和林下草本层物种多样性指数,探究林分因子对林下草本物种多样性指数和林分结构的影响。结果显示:(1)除林分密度、平均冠幅和平均胸径外,其他林分因子都有显著性差异;林分密度的变异程度最高,平均林龄变异程度最低。(2)4种草本多样性指数在各样地之间均存在显著性差异,其中物种丰富...
以广西高峰林场的10、12、18和51 a灰木莲人工林为研究对象,对比分析土壤中微量元素Fe、Mn、Cu、Zn、B、Al在不同林龄林分中的含量差异及其与土壤有机质、pH值及物理性质之间的相关性,为评价灰木莲人工林的土壤改良效果及养分管理提供依据。结果显示:(1)林龄变化对土壤微量元素含量特征存在显著影响(P《0.05),其中土壤微量元素Fe、Mn、Cu、Zn含量均随着林分年龄的增加而显著增加,有效...
云南省热带作物科学研究所技术：生态胶园创建技术（图）
云南省热作所 生态胶园 创建技术
2023/11/23
技术概述：针对目前橡胶树种植业经济收益较低、生态功能较弱、抗风险能力较差的现状，按照生态学和经济学原理，从植胶区自然环境特点出发，通过改善胶园种植结构，改变传统的单一作物（植物）种植模式和改进现有胶园管理措施，构建以橡胶树为主的复合农林生态系统，建设生态胶园，增加胶园的生物多样性，提升胶园生态功能和经济功能，实现胶园的可持续健康发展。
Ecological Potential of Mediterranean Habitats for Black Pine (Pinus nigra J.F. Arnold) in Croatia
reforestation succession forest vegetation pine plantations karst
2023/11/22
This study outlines research performed on experimental plots established in forest plantations and in natural black pine forests. The objective of the study was to determine the habitat factors that h...
Integrated Harvesting of Medium Rotation Hybrid Poplar Plantations: Systems Compared
mass handling WTH CTL Integrated Harvesting MRC ex-arable land
2023/11/22
In this study, the authors provide a direct comparison made between whole tree-harvesting (WTH) and cut-to length (CTL) methods, which was conducted in two sites in the Slovak Republic and applied to ...
Soil Organic Nitrogen Components and N?Cycling Enzyme Activities Following Vegetation Restoration of Cropland in Danxia Degraded Region
reforestation succession forest vegetation pine plantations karst
2023/11/22
This study outlines research performed on experimental plots established in forest plantations and in natural black pine forests. The objective of the study was to determine the habitat factors that h...
CO2 Emissions Accounting and Carbon Peak Prediction of China’s Papermaking Industry
paper and paper products LCA CO2 emissions carbon peaking
2023/11/22
China has been the world’s largest producer and consumer of paper products. In the context of the “carbon peaking and carbon neutrality goals”, China’s papermaking industry which is traditionally a hi...
Differential Response of Soil Respiration and Total Belowground Carbon Allocation to Simulated Nitrogen and Phosphorus Deposition in Moso Bamboo Forests
N and P deposition autotrophic respiration heterotrophic respiration net ecosystem production root carbon-use efficiency
2023/11/22
Elevated nitrogen (N) and phosphorus (P) depositions have greatly affected belowground carbon processes in forest ecosystems. However, open questions still remained on the effects of N and P depositio...
Trade-Offs and Synergies between Plant Species Diversity and Water Retention Capacity of Pinus massoniana Plantation Community in Danjiangkou Reservoir Area
Pinus massoniana plantation plant species diversity trade-off synergistic ecosystem service Danjiangkou reservoir area
2023/11/22
In order to quantify the plant species diversity characteristics of Pinus massoniana plantations with different stand densities in the Danjiangkou reservoir area of Hubei Province and the relationship...
Effect of Species Composition on Growth and Yield in Mixed Beech–Coniferous Stands
mixed stand soil trophicity mean height dominant height species composition mean annual volume increment
2023/11/22
Research Highlights: In mixed stands, competitive and supportive relationships occur between trees, illustrated by their dendrometric characteristics. Background and Objectives: We investigated the ef...
Error Analysis on the Five Stand Biomass Growth Estimation Methods for a Sub-Alpine Natural Pine Forest in Yunnan, Southwestern China
above-ground biomass biomass growth error analysis Pinus densata forests
2023/11/22
Forest biomass measurement or estimation is critical for forest monitoring at the stand scale, but errors among different estimations in stand investigation are unclear. Thus, the Pinus densata natura...
A Comparison of Soil C, N, and P Stoichiometry Characteristics under Different Thinning Intensities in a Subtropical Moso bamboo (Phyllostachys edulis) Forest of China
thinning intensity carbon ecological stoichiometry Moso bamboo (Phyllostachys edulis) forest soil nutrient stocks soil fertility
2023/11/22
Land management using suitable thinning intensities can promote the yield of Moso bamboo (Phyllostachys edulis) forests and alter the nutrient content and stoichiometric characteristics within the soi...
Abnormal Litter Induced by Typhoon Disturbances Had Higher Rates of Mass Loss and Carbon Release than Physiological Litter in Coastal Subtropical Urban Forest Ecosystems
abnormal litter carbon cycle coastal urban forest litter decomposition physiological litter tropical cyclones
2023/11/22
The decomposition of abnormal litter caused by extreme weather events might play an increasingly important role in carbon and nutrient cycling in forest ecosystems under climate change scenarios, whic...
Modeling Tree Growth Responses to Climate Change: A Case Study in Natural Deciduous Mountain Forests
biotic and abiotic factors climate change Hyrcanian Forest machine learning RCP scenarios
2023/11/22
Climate change has significant effects on forest ecosystems around the world. Since tree diameter increment determines forest volume increment and ultimately forest production, an accurate estimate of...