Arbor Layer Research Articles

Tree biomass distribution patterns with a forest succession in subtropical China

AbstractTo better understand the effect of forest succession on biomass sequestration, we investigated biomass stock and allocation of evergreen broadleaf forest, a major zonal forest type in subtropical China. To analyze the biomass patterns and dynamics with forest succession, three forest types, pine (Pinus massoniana Lamb.) forest (PF), pine and broadleaf mixed forest (MF) and evergreen broadleaf forest (BF), were selected and their tree biomasses were investigated. The results showed that the biomass of the arbor layer was the highest in BF, which was 292.51 t/hm2, followed by MF and PF with 206.87 and 171.76 t/hm2, respectively. It indicated that tree biomass increased with the forest succession. The biomass patterns in arbor layer were similar during the forest succession, in which the biomass of trunks accounted for the largest proportion in the total biomass decreased with the forest succession, but the proportion of the biomass of roots increased with the forest succession. The biomass of the diameter class above 20 cm in PF, MF and BF contributed to a large proportion of the total biomass. With the succession, the increase of tree species diversity has a positive effect on the increase of tree biomass. Our results indicated that forest succession can sequestrate biomass carbon and alleviate the global climate change.

Karren Habitat as the Key in Influencing Plant Distribution and Species Diversity in Shilin Geopark, Southwest China

Karst rocky desertification (KRD) is one of the biggest challenges in the karst ecological restoration of Southwest China, and a thorough understanding of the plant community characteristics in various karren habitats provides a basis for mitigating KRD and restoring the degraded ecosystem. To improve our knowledge of the detailed characteristics and impact mechanisms of karren habitats on the species distribution and species diversity patterns of woody and herbaceous plants to benefit sustainable management and planting design for revegetation establishment in the karst region, a field investigation was carried out in the natural restoration vegetation of Shilin Geopark. The results indicated that karren habitats apparently determine the species diversity and composition. At the arbor layer, the habitat with the highest α diversity was solution corridor (SC), and at the shrub layer, grikes (GR) were the karren habitats with the most diverse communities. At the herb layer, solution rock debris (SRD) showed the highest richness of herbaceous species. The karren habitat features and topographic factors significantly influence plant α diversity and distribution. Soil area (SA) and canopy density (CD) were the dominant factors influencing plant diversity at the arbor, shrub and herb layers, soil thickness (ST) was significantly effective at the arbor and herb layers. Karren habitat height (KHH), litter thickness (LT), and slope gradient (SG) were significantly influential at the herb layer. The impacts of the karren habitat width (KHW), slope aspect (SAS), and SG on woody species distribution were significant. Knowledge obtained from this study will be helpful guidance for future sustainable restored vegetation design and management with high biodiversity and regional characteristics in the karst area of Southwest China and other fragile karst ecosystems in the world.

Variation in Near-Surface Airborne Bacterial Communities among Five Forest Types

Airborne bacteria play important roles in air pollution, human health and biogeochemical cycles. However, their spatial variation and determinant factors in forest environments are poorly understood. In this study, we selected five forest types in the Liuxihe National Park, South China, to analyze how near-surface bacterial community structure is related to the forest community structure and soil physicochemical properties. The results indicated that the dominant communities were mainly constituted by seven bacterial genera of the phyla Proteobacteria (49.7%–55.4%) and Firmicutes (44.2%–49.8%), including Exiguobacterium (42.0%–46.4%), Citrobacter (20.7%–25.8%), Acinetobacter (20.1%–22.1%), and Pseudomonas (7.8%–8.9%) etc. However, differences in the composition and diversity of the airborne bacterial communities were evident among the five forests, especially with respect to the dominant taxa. The relative abundance of Enterococcus and Bacillus in coniferous and broad-leaved mixed forest (MF), broad-leaved mixed forest (BF), and pure Cunninghamia lanceolata forest (CL) was significantly higher than that of the other forests, while the relative abundance of Citrobacter was significantly lower. The relative abundance of Citrobacter, Acinetobacter, and Pseudomonas in Proteobacteria were significantly negatively correlated with plant diversity and acid phosphatase activity but positively correlated with soil pH and soil available potassium. Contrastingly, the correlation between the relative abundance of most genera of Firmicutes and the above environmental factors is just the opposite of that for Proteobacteria. We provide direct evidence that native plant communities in the middle stage of succession, compared to planted forests and forest open space, generally had higher airborne bacterial diversity. Airborne bacterial diversity showed a significantly positive correlation with plant diversity (p < 0.05). Over all, soil pH, soil available potassium, and soil available phosphorus contributed to a high rate of the diversity of the airborne bacterial community in near-surface, followed by the plant diversity of the arbor layer and the near-surface air temperature. These results extended our understanding of the ecological patterns of airborne bacteria in forest ecosystems.

Study on the Coupling Relationship Between Arbor Layer Structure and Shrub Layer Diversity of Chinese Pine Plantation Forests

Study on the Coupling Relationship Between Arbor Layer Structure and Shrub Layer Diversity of Chinese Pine Plantation Forests

Effects of retention density on growth, biomass, and economic benefit of Cunninghamia lanceolata plantation

We examined the effects of retention density on plant DBH (diameter at breast height), height, volume growth, stand biomass, and stand economic benefit of Cunninghamia lanceolata plantation by Pingxiang, Guangxi Province. Four treatments of different retention density were set up a 14-year middle-aged Cunninghamia lanceolata plantation, 500, 750 and 1000 trees·hm-2, with stand without thinning as the control (1500 trees·hm-2). Results showed that DBH (20.55 cm), increment in height (15.70 m), and large-diameter timber volume (18.31 m3·hm-2) of the C. lanceolata plantation were the highest in 500 trees·hm-2 treatment. The volume of living trees was the highest in the control (199.63 m3·hm-2), which was significantly higher than that in 500 and 750 trees·hm-2. The biomass of arbor layer and ecosystem, as well as the economic benefit differed significantly across the treatments, with arborous biomass (90.72 t·hm-2), ecosystem biomass (94.97 t·hm-2), and economic benefit (1.184×105 yuan·hm-2) of 1000 trees·hm-2 treatment being significantly higher than others. Reducing stand retention density increased the DBH, plant height, timber diameter, proportion of large diameter timber, average volume and biomass of single timber, but it did not enhance the volume of living trees. The retention density of 1000 trees·hm-2 was the optimum for middle-aged C. lanceolata plantation. Compared with the control, it significantly increased the total stand volume, arbor biomass, ecosystem biomass, and economic benefit by 2.3%, 5.7%, 4.7%, and 5.8%, respectively.

珍稀濒危树种陆均松天然种群结构与空间分布格局

PDF HTML阅读 XML下载 导出引用 引用提醒 珍稀濒危树种陆均松天然种群结构与空间分布格局 DOI: 10.5846/stxb201905090948 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 中央级公益性科研院所基本科研业务费专项资金（CAFBB2017ZB004） Natural population structure and spatial distribution pattern of rare and endangered species Dacrydium pectinatum Author: Affiliation: Fund Project: Study on the Monitoring and Exhaustion Mechanism of Dacrydium Pierrei Resources 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:为研究陆均松（Dacrydium pectinatum）种群生存现状及分布格局，对BWL、DLS、JFL 三种不同分布区域的陆均松天然种群进行了调查，分析了其天然群落乔木层物种多样性及优势种组成、龄级结构及分布格局三个方面的空间异质性，结果表明：（1）三种陆均松天然群落乔木层物种丰富度及多样性指数均较高，基本表现为BWL>JFL>DLS，且远高于中高纬度温带及亚热带森林群落；群落内多为小密度种群，少有占绝对优势地位的树种，符合热带山地雨林物种组成的一般规律。（2）龄级结构有所差异，BWL和JFL种群呈衰退趋势，共同特点是幼年树数量较少，成年和老年树比例较高；DLS种群幼年树数量在所有个体中比例最高，属于增长型种群。（3）BWL和DLS种群整体呈聚集分布，幼年至老年阶段由聚集分布转变为均匀分布，JFL种群整体及不同发育阶段均呈均匀分布状态；聚集强度表现为DLS > BWL > JFL，幼年树 > 成年树 > 老年树。陆均松是热带山地雨林的关键种和建群种，对研究海南热带雨林的起源及其区系特征具有重要意义，针对其生存现状，可根据实际情况，利用人工辅助措施如开辟林窗、合理疏伐等方式进行保护及更新复壮。 Abstract:In order to study the survival status and distribution pattern of Dacrydium pectinatum population, we investigated three different distribution areas, namely BWL, DLS, and JFL in Hainan Island. The spatial heterogeneity in three aspects of the species diversity and dominant species composition of the natural community arbor layer, age structure, and distribution pattern was analyzed. The results showed that (1) the arbor layer species abundance and diversity index of the three D. pectinatum natural community were higher as a whole, which followed the order of BWL > JFL > DLS, and much higher than those of the mid-high latitude temperate zone and subtropical forest community. The populations in the community were mostly small-density populations, and there were few absolutely dominant species, which is consistent with the general rule of species composition of tropical mountain rainforests. (2) The age structure of these three populations had its own characteristics. BWL and JFL showed a recession trend. The common feature was that the number of Juvenile tree was small, and the proportion of adult trees and elderly trees was high. The number of Juvenile tree in DLS was the most for all individuals and belonged to the growth population. (3) The overall state of the D. pectinatum population of BWL and JFL was aggregate clustered distribution. The juvenile tree stage was also a clustered distribution, but in the elderly tree stage, it changed from clustered distribution to uniform distribution. The JFL D. pectinatum population showed a uniform distribution throughout all individuals and different developmental stages. Their aggregation intensity was expressed as DLS > BWL > JFL and juvenile > adult > elderly. D. pectinatum is a key species of tropical mountain rainforests, which is of great significance for studying the origin and flora characteristics of Hainan tropical rainforest. For its current survival status, we can use manual auxiliary measures such as opening forest windows and rational thinning to protect and rejuvenate D. pectinatum population based on the actual situation. 参考文献 相似文献 引证文献

川西米亚罗自然保护区森林地上碳储量遥感估算

PDF HTML阅读 XML下载 导出引用 引用提醒 川西米亚罗自然保护区森林地上碳储量遥感估算 DOI: 10.5846/stxb201807281610 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 四川省科技厅应用基础项目（2017JY0155）；四川省中医药管理局重大专项（2018PC005） Estimation of forest aboveground carbon storage in Sichuan Miyaluo Nature Reserve based on remote sensing Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:研究米亚罗自然保护区的森林地上碳储量，有利于掌握高山峡谷区森林植被碳储量的分布特点，对区域森林资源的有效科学管理和维护森林生态环境具有重要意义。通过对保护区内的7个主要树种分别构建模型来初步估测森林地上碳储量，利用实地调查的样地数据与同期Landsat 8遥感卫星影像，得到波段信息、植被指数、主成分分析、纹理特征、地形因子、植被生长六大类共80个因子，用以构建乔木层不同树种地上碳储量的多元线性逐步回归模型，而灌木层的碳储量则由生物量密度法估算得出。研究结果表明：①模型预测值与实测值相关系数在0.675-0.775之间，精度较高，预测结果可靠；②米亚罗自然保护区森林地上碳储量为5.861 Tg，其中乔木层5.632 Tg，灌木层0.229 Tg。云冷杉林是研究区分布最广的林分类型，其碳储量为5.098 Tg，占森林地上碳储量总量的86.98%，在维持区域碳平衡方面发挥着重要作用。③研究区森林平均碳密度为53.138 t/hm2，其中冷杉的碳密度最高，达到74.467 t/hm2。④区域内森林地上碳储量以杂谷脑河流域及支流为中心，以一定缓冲距离呈树枝状发散分布，海拔3000-4000 m区域的森林植被碳储量最大，且阴坡的碳储量明显高于阳坡。 Abstract:The Miyaluo Nature Reserve is an important carbon sequestration region in Western Sichuan. Study of aboveground forest carbon storage in Miyaluo Nature Reserve is necessary for elucidating the distribution characteristics of forest vegetation carbon storage in alpine gorge areas. Furthermore, it is of great significance to the scientific management of forest resources and the maintenance of forest ecological environments in the nature reserves. In this study, carbon storage models were established for seven main tree species to estimate the carbon storage on forest land. Firstly, 897 samples were obtained from a field survey, and sample biomass and carbon storage were calculated based on the volume-derived biomass method. Secondly, Landsat 8 satellite remote sensing data were used to obtain image characteristics of forest vegetation. Thirdly, combined with forest survey data, 80 factors were determined that were classified into six categories (band information, vegetation index, principal component analysis, texture features, topographic factors, and vegetation growth). Moreover, the correlation between these factors and the biomass of different tree species was analyzed, according to the order of Pearson's correlation coefficient, the significant correlation factors were then introduced into the multiple linear stepwise regression equation as independent variables, and the estimation models of aboveground carbon storage of different tree species in the tree layer were established. Finally, the aboveground carbon storage of the arbor layer was calculated by the estimation model, and the carbon storage in the shrub layer was calculated using the average biomass density method. The results showed that ① the accuracy of models for carbon storage estimation was within the margin of error, and the correlation coefficient between the measured value and the predicted value of the model was 0.675-0.775. ② The total carbon storage in the forest in the Miyaluo Nature Reserve was 5.861 Tg, of which the aboveground carbon storage in the arbor layer was 5.632 Tg, and the carbon storage in the shrub layer was 0.229 Tg. The order of the aboveground carbon storage of the prominent species was Abies faberi > Picea asperata > Tsuga chinensis > Larix gmelimi > Quercus acutissima > Betula chinensis > Pinus tabulaeformis > Pinus armandi; The total carbon storage of fir trees was 5.098 Tg, accounting for 86.98% of the aboveground carbon storage in the study area. The spruce-fir forest was the most widely distributed forest type in the Miyaluo Nature Reserve, and it played an important role in maintaining the carbon balance. ③ The average carbon density in the forest in Miyaluo Nature Reserve was 53.138 t/hm2, and the carbon density of Chinese fir species was higher than the average. The carbon density of fir was much higher than that of other tree species and was 74.467 t/hm2. ④ The spatial distribution characteristics of aboveground forest carbon storage in the study area were obtained by overlapping the Digital Elevation Model (DEM) with carbon storage. Taking the Zagunao River and its tributaries as the center, the carbon storage spatial distribution data were extended to the surrounding area by a given buffer distance in the whole region, similar to arborization. The largest area of forest vegetation carbon storage was distributed in regions with elevation of 3000-4000 m. The aboveground carbon storage on shady slopes was higher than that on sunny slopes. 参考文献 相似文献 引证文献

The Impact of Near Natural Forest Management on the Carbon Stock and Sequestration Potential of Pinus massoniana (Lamb.) and Cunninghamia lanceolata (Lamb.) Hook. Plantations

Quantifying the impact of forest management on carbon (C) stock is important for evaluating and enhancing the ability of plantations to mitigate climate change. Near natural forest management (NNFM) through species enrichment planting in single species plantations, structural adjustment, and understory protection is widely used in plantation management. However, its long-term effect on forest ecosystem C stock remains unclear. We therefore selected two typical coniferous plantations in southwest China, Pinus massoniana (Lamb.) and Cunninghamia lanceolate (Lamb.) Hook., to explore the effects of long-term NNFM on ecosystem C storage. The C content and stock of different components in the pure plantations of P. massoniana (PCK) and C. lanceolata (CCK), and their corresponding near natural managed forests (PCN and CCN, respectively), were investigated during eight years of NNFM beginning in 2008. In 2016, there was no change in the vegetation C content, while soil C content in the 0–20 cm and 20–40 cm layers significantly increased, compared to the pure forests. In the P. massoniana and C. lanceolata plantations, NNFM increased the ecosystem C stock by 31.8% and 24.3%, respectively. Overall, the total C stock of soil and arborous layer accounted for 98.2%–99.4% of the whole ecosystem C stock. The increase in the biomass of the retained and underplanted trees led to a greater increase in the arborous C stock in the near natural forests than in the controls. The NNFM exhibited an increasingly positive correlation with the ecosystem C stock over time. Long-term NNFM enhances ecosystem C sequestration by increasing tree growth rate at individual and stand scales, as well as by likely changing the litter decomposition rate resulting from shifts in species composition and stand density. These results indicated that NNFM plays a positive role in achieving multi-objective silviculture and climate change mitigation.

Multifactor relationships between stand structure and soil and water conservation functions of Robinia pseudoacacia L. in the Loess Region.

Ninety-six sample plots were established for a tree census to explore the multifactor relationships between the soil and water conservation functions and the stand structure in a typical black locust (Robinia pseudoacacia L.) plantation in the Caijiachuan watershed of the Loess Plateau, Western Shanxi Province, China. Based on the observational and experimental data, a topography-structure-function model was built using a structural equation modeling (SEM) approach. The latent variables were the topographical factors, horizontal structure, vertical structure, soil and water conservation, and sediment reduction. The results indicated that the horizontal structure of the Robinia pseudoacacia L. forest was the most obvious latent variable, which was expressed in the path coefficient (pc = 0.85) corresponding to the sediment reduction; the stand density and tree competition index were the major drivers of the structure, with path coefficients of −0.96 and −0.92 and influence coefficients of −0.997 and −0.998. These factors are easily regulated. Among these factors the stand density of the arbor layer is recommended to be kept stable within the range from 1600 to 1700 trees/hm2. These relationships showed that reducing the tree competition index and changing the microtopography could effectively enhance the soil and water conservation functions in this ecologically significant loess area.

Numerical analysis of inter-specific relationships in Arbor layer of Pinus syluestriformis community in Changbai Mountain area, China

Pinus syluestriformis is a rare and endemic tree species in Changbai Mountain, China’s national first-class protected plant. In recent years, with the increase in population and environmental damage, the number is becoming less and reaching the edge of extinction. The interspecific association characteristics of dominant species in Arbor layer of Pinus syluestriformis community were analyzed by using 2×2 contingency table, variance analysis, association coefficient, chi-square test, and Spearman rank correlation test. The results showed that: (1)The overall relevance showed negative correlation. Both AC and PCC were used to describe the degree of association between species, and they had high similarities. In the pure forest, Pinus syluestriformis and the main arbor species were positively correlated, but did not reach a significant level.In the scattered forest, the correlations between Pinus syluestriformis and the main arbor species were positively correlated with only Acer barbinerve, Albizia kalkora, and Tilia amurensis, and negatively correlated with other species. (2)In the pure forest, Spearman rank correlation analysis showed 72 pairs were positively correlated. In the scattered forest, 14 dominant species with high important values in the community were selected for analysis. Spearman rank correlation coefficient reflected that 23 pairs were positively correlated. (3) The results of the tests are positive and negative correlation ratio <1, which reflected the unstable early succession stage of plant community. The community was susceptible to the interference of external factors and succeeded.

Ecosystem Carbon Allocation of a Temperate Mixed Forest and a Subtropical Evergreen Forest in China

Ecosystem carbon allocation can indicate ecosystem carbon cycling visually through its quantification within different carbon pools and carbon exchange. Using the ecological inventory and eddy covariance measurement applied to both a mature temperate mixed forest in Changbai Mountain (CBM) and a mature subtropical evergreen forest in Dinghu Mountain (DHM), we partitioned the ecosystem carbon pool and carbon exchange into different components, determined the allocation and analyzed relationships within those components. Generally, the total carbon stock of CBM was slightly higher than that of DHM due to a higher carbon stock in the arbor layer at CBM. It was interesting that the proportions of carbon stock in vegetation, soil and litter were similar for the two mature forests. The ratio of vegetation carbon pool to soil carbon stock was 1.5 at CBM and 1.3 at DHM. However, more carbon was allocated to the trunk and root from the vegetation carbon pool at CBM, while more carbon was allocated to foliage and branches at DHM. Moreover, 77% of soil carbon storage was limited to the surface soil layer (0-20 cm), while there was still plentiful carbon stored in the deeper soil layers at DHM. The root/shoot ratios were 0.30 and 0.25 for CBM and DHM, respectively. The rates of net ecosystem productivity (NPP) to gross ecosystem productivity (GPP) were 0.76 and 0.58, and the ratios of ecosystem respiration (Re) to GPP were 0.98 and 0.87 for CBM and DHM, respectively. The net ecosystem carbon exchange/productivity (NEP) was 0.24 t C ha–1 yr–1 for CBM and 3.38 t C ha–1 yr–1 for DHM. Due to the common seasonal and inter-annual variations of ecosystem carbon exchange resulting from the influence of environmental factors, it was necessary to use the long record dataset to evaluate the ecosystem sink capacity.

Distribution characteristics and factors influencing the ecosystem in western Hubei

Western Hubei is the most concentrated area of forest resources in Hubei Province, and the knowledge of the distribution characteristics of ecosystem carbon density is important to understand the regional characteristics of carbon density and its mechanism of formation. Carbon density and factors influencing different layers in the ecosystem were studied by using field data. The average carbon density of ecosystems in western Hubei was 159.05t/hm2; the carbon density of different forest types in descending order was Abies fargesii forests (362.25t/hm2), mixed broadleaf-conifer forests (154.13t/hm2), broad-leaved forests (146.09t/hm2), and coniferous forests (135.76t/hm2), and ecosystem carbon density increased with increasing age. The carbon density of the arborous layer, shrub layer, and soil layer of A. fargesii forests was significant higher than that of the other forests (P<0.05), indicating the carbon storage per unit area of A. fargesii forests, which grow at higher elevations, was the greatest. The carbon density in arborous layers of broad-leaved forests, mixed broadleaf-conifer forests, and coniferous forests was 39.29t/hm2, 48.99t/hm2, and 48.39t/hm2, respectively. Those of the soil layer were 102.96t/hm2, 100.97t/hm2, and 82.37t/hm2, respectively, and there were no significant differences among them. Among the three forest types, carbon density in the litter layer was greater than that of the shrub layer, which indicated the litter layer plays an important role in carbon storage. The carbon density of mixed broadleaf-conifer forests was greatest, excluding A. fargesii forests, in medium (58.71t/hm2) and mature forests (79.66t/hm2). Thus, the carbon sink of mixed broadleaf-conifer forests had more potential than the others at the medium and mature forest stage. The soil layer carbon density in different forests constituted 60.67—70.48% of the entire ecosystem, and was 1.70—2.62 times greater than that of the arborous layer. There are many factors influencing ecosystem carbon density, which result from the interaction of environmental and topographical factors. The main explanatory variables of carbon density of the region were altitude, precipitation, and canopy density. The vegetation and soil layer carbon density increased as altitude increased, and the rate of change for every vertical 100m was 1.3t/hm2 and 1.9t/hm2, respectively (P<0.05). Although the annual average precipitation only affected the carbon density of the vegetation, it increased to 4t/hm2 (P<0.01) when average precipitation was >100mm.

太行山东坡不同林龄杏树林碳储量及其分配特征

PDF HTML阅读 XML下载 导出引用 引用提醒 太行山东坡不同林龄杏树林碳储量及其分配特征 DOI: 10.5846/stxb201803290634 作者: 作者单位: 河北省科学院地理科学研究所,河北省科学院地理科学研究所,河北省科学院,河北省科学院地理科学研究所,河北省科学院地理科学研究所,中国科学院遗传与发育生物学研究所农业资源研究中心,河北省科学院地理科学研究所,河北省科学院地理科学研究所 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目（3150048）；河北省科学院科技攻关项目（18111）；河北省青年拔尖人才项目；河北省科学院青年拔尖人才项目 Carbon storage and its allocation pattern in Armeniaca vulgaris plantations at different ages on the eastern slope of Taihang Mountain Author: Affiliation: Institute of Geographical Sciences,Hebei Academy of Sciences,Institute of Geographical Sciences,Hebei Academy of Sciences,Hebei Academy of Sciences,Institute of Geographical Sciences,Hebei Academy of Sciences,Institute of Geographical Sciences,Hebei Academy of Sciences,Center for Agricultural Resources Research,Institute of Genetics and Developmental Biology,Chinese Academy of Sciences,Institute of Geographical Sciences,Hebei Academy of Sciences,Institute of Geographical Sciences,Hebei Academy of Sciences Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:在生物量调查的基础上，对太行山东坡4、8、12年生和16年生杏树林生态系统碳储量及其分配特征进行了研究。结果表明：杏树各器官碳含量在447.3-488.1 g/kg；树干碳含量随林龄的增长而显著降低（P < 0.05），不同林龄间树根、树枝和树叶碳含量无显著差异；土壤层（0-100 cm）碳含量随林龄的增长而增大；随土层深度的增加而降低。林龄对杏树林乔木层、土壤层和生态系统碳储量均有显著影响。4、8、12年生和16年生杏树林生态系统碳储量分别为27.810、72.647、82.450 Mg/hm2和102.336 Mg/hm2；土壤层碳储量占总碳储量的90.1%-99.6%，且主要集中于0-40 cm。乔木层碳储量分配随着林龄的增长而增加，土壤碳储量分配则减小。结果揭示了土壤层是杏树林生态系统的主要碳库；杏树人工林生态系统在生长过程中能显著地积累有机碳。研究结果可为经济林经营管理及碳汇功能评价提供参考。 Abstract:Carbon storage and its allocation of 4-, 8-, 12-, and 16-year-old Armeniaca vulgaris plantation ecosystems on the eastern slope of Taihang Mountain were studied based on a biomass survey. The results showed that the carbon contents in different organs of apricots ranged from to 447.3 to 488.1 g/kg. The carbon content of stems decreased significantly with stand age, whereas no significant differences in carbon content were observed among the roots, branches, and leaves of the apricot plantations with different ages. The carbon content in the soil layer (0-100 cm) increased significantly with increasing stand age, but decreased with increasing soil depth (P < 0.05). The carbon storage in the arbor layer, soil layer, and whole ecosystem of the apricot plantations was obviously age dependent. The values of total carbon storage in the 4-, 8-, 12-, and 16-year-old apricot plantation ecosystems were 27.810, 72.647, 82.450 Mg/hm2 and 102.336 Mg/hm2, respectively. The carbon storage in the soil layer accounted for >90.1%of the carbon storage in the apricot plantation ecosystem, which was accumulated at higher levels in the 0-40 cm soil layer. The carbon storage and distribution patterns in the apricot plantations varied obviously with the stand age. In addition, carbon storage allocation increased in the arbor layer but decreased in the soil layer with increasing stand age. Our results suggested that the soil layer was the major carbon pool, and also impliedthat the plantation ecosystems at these stand ages could accumulate organic carbon continuously. Quantifying carbon storage and distribution patterns of apricot plantationscould help design sustainable forest management strategies for achieving its potential in mitigating climate change. 参考文献 相似文献 引证文献

海拔梯度对祁连山青海云杉林乔木层和土壤层碳密度的影响

海拔梯度对祁连山青海云杉林乔木层和土壤层碳密度的影响

Characteristics of Carbon Storage and Density in Different Layers of Forest Ecosystems

Characteristics of carbon storage and density in different layers of forest ecosystems should be studied comprehensively and in more detail. Using forest inventory data in combination with field survey data, we explored the characteristics of carbon storage and density in different layers of forest ecosystems in Liaoning Province of China. Results showed that total carbon storage was 813.034 Tg C. The carbon storage of soil layer accounted for 81.0% of the total storage with 658.783 Tg C, followed by those of arbor, litter and shrub layers with 128.403 Tg C (15.8%), 22.723 Tg C (2.8%) and 3.125 Tg C (0.4%), respectively. The average carbon density for the forest ecosystems were 183.571 Mg C ha–1, with soil layer (148.744 Mg C ha–1) being the highest one, followed by arbor layer (28.992 Mg C ha–1), litter layer (5.131 Mg C ha–1) and shrub-grass layer (0.706 Mg C ha–1). Carbon storage in different forest ecosystems varied from 1.595 to 319.161 Tg C, while C density ranged from 165.067 to 235.947Mg C ha–1, with the highest and lowest values being observed in soil layer and shrub-grass layers, respectively, implying that soil is the main body of forest carbon storage. Young-aged forests accounted for a greater proportion of forests in the Province than forests in other age classes; and proper management of forests could increase the carbon sequestration in the forest ecosystems. The comparison with previous estimations of carbon storage for forest ecosystem implied that methods and data used for forest carbon storage estimation affected the results of estimates obviously.

2011-2016年武夷山甜槠常绿阔叶林乔木层群落动态

2011-2016年武夷山甜槠常绿阔叶林乔木层群落动态

Addition effects of co-expansion of two bamboos on plant diversity in broad-leaved forests

The effects of Phyllostachys edulis and Oligostachyum oedogonatum expansion on species diversity of broad-leaved forests were investigated in Wuyishan National Nature Reserve, Jiangxi Province, China. Ph. edulis and/or O. oedogonatum expansion changed community structure and species composition. The co expansion of the two bamboos in high intensity (Ph. edulis was 30-50 ind·100 m-2, O. oedogonatum was 300-500 ind·100 m-2) changed the density ratio of arbor and shrub from 2:8 to 1:9, and density ratio of bamboo and tree from 0:10 to 9:1. The main effects of Ph. edulis and O. oedogonatum on the species diversity were significant. Ph. edulis mainly influe-nced arbor layer, while O. oedogonatum influenced shrub layer more, and the interaction effect of two bamboos was not remarkable. There existed addition effects between Ph. edulis and O. oedogonatum on species diversity. The co-occurrence of two bamboos in high intensity decreased the Shannon index of community by 91.3%. Ph. edulis and O. oedogonatum did not compete obviously unless in high density. It was addition effect rather than interaction effect that changed the community structure and reduced species diversity when broad leaved forest suffered invasion by Ph. edulis and O. oedogonatum.

Plant community characteristics and their relationships with soil properties in a karst region of southwest China

In this study, we analyzed plant community characteristics and the relationship between plant and soil properties based on forest successional stages in depressions between karst hills. The secondary forests showed the maximum number of species, genera, and families with important values >5 and the highest species diversity, and primary forest was the optimal community structure. The arboreal layer played a dominant role in determining fragile karst ecosystem status, followed by shrubs, Al2O3, and Fe2O3. A close relationship existed between species diversity and soil organic C, total N, total P, Fe2O3, MnO, microbial biomass C, and microbial biomass P. Plant characteristics could be explained by the soil nutrient factors (21.6%), soil microbes (17.1%), soil mineral components (10.2%), and interactions among these variables (29.3%).

Stratification of the ant species (Hymenoptera, Formicidae) in the urban broadleaf woodlands of the city of Kiev

Investigations were carried out in June–August 2012 and 2013 in broadleaf forests and planted stands of the northern red oak Quercus rubra in Kiev. The ant visitation rates of 3–6 most abundant plant species within each vegetation layer were analyzed. In all, 16 species of ants were found in the broadleaf forest (Quercus robur + Acer spp. + Carpinus betulus), with the dominance of three species: Formica rufa, Lasius fuliginosus, and L. emarginatus. Eight ant species occurred in Q. rubra stands with the undergrowth of Acer campestre and A. platanoides; the dominant species were Lasius fuliginosus and L. emarginatus. The northern red oak stands with conspecific undergrowth had only four ant species with no dominants among them. Plants with the highest ant visitation rates in the herbage layer of the broadleaf forest were the invasive Impatiens parviflora and the native Aegopodium podagraria. Ants were rare or absent on the remaining herbs: Impatiens noli-tangere, Carex sylvatica, Stellaria holostea, and Galium odoratum. The herbage layer was mostly visited by influents, the dominants being represented only by Lasius emarginatus. Within the shrub layer, ants most frequently visited the undergrowth of the maple Acer platanoides, often harboring colonies of the aphid Periphyllus lyropictus; the highest visitation rates were recorded in the dominants L. emarginatus and L. fuliginosus. The arboreal layer had the highest visitation rate and was most often visited by the dominants Lasius fuliginosus, L. emarginatus, and F. rufa. The common oak Q. robur was the most visited tree in broadleaf forests. In addition to providing ants with food (colonies of the aphids Lachnus roboris and Stomaphis quercus, and also phytophagous insects and other invertebrates), these trees were used for nesting by the dominants L. fuliginosus and L. emarginatus. The presence of aphid colonies was also typical of ripe trees and undergrowth of the maple A. platanoides, the second-visited tree in broadleaf forests. The common hornbeam Carpinus betulus was the least frequently visited, though some ant species, usually L. emarginatus, nested in the trunks and branches of old trees. The vertical distribution of ants in broadleaf forests and red oak stands formed two clusters: the influents occupied the lower (herbage and shrub) vegetation layers, while the subdominants and dominants occupied the upper (shrub and arboreal) ones. The smallest number of ant species (1 or 2) in all the vegetation layers was recorded in the areas with F. rufa; areas with L. fuliginosus had twice as many species; the greatest numbers of ant species were found in the areas with L. emarginatus and in those without dominants. This pattern may result from different territoriality of the dominants: the strongest in F. rufa (defending the whole territory) and the weaker in the other two species (defending only a part of the territory). Plants of all the vegetation layers varied in their attractiveness to ants. As a result, the layers had a mosaic structure in their vertical (between-layer) and horizontal (between different plant species within one layer) arrangement. From 60 to 100% of plants of certain species were visited by ants while plants of other species were not visited at all. The main reason for visiting plants by ants was the presence of aphid colonies.

Phytosociology as a tool for forest restoration: a study case in the extreme South of Atlantic Forest Biome

The biodiversity loss, due to anthropic activities, has generated the necessity of studies that enable the ecosystem conservation. Nevertheless, the majority of studies restrict themselves to the floristic composition and phytosociological structure from determined pre-established diameter, neglecting attributes of the species, such as its (their) niche (s) of occurrence in the forest, thus, making it difficult to identify potential species for restoration. In this way, the present study aimed to evaluate the structure of a forest fragment in the extreme South of Atlantic Forest Biome, through identification of species in the different layers. There were used 18 parcels of 10 m × 20 m, distributed systematically, where the vegetation was evaluated in four size classes. The characterization of the structure of the arboreal-shrub of the forest was performed by the data comparison of the floristic composition and phytosociological structure. In the fragment of forest studied, there were sampled a total of 2.176 individuals. The floristic composition of the area includes 74 species, belonging to 58 genera and 28 botanical families. We observed differences in relation of richness and diversity of species among the analyzed layers, the intermediate layer presented the lowest richness of species, being the pioneers and initial secondaries the least representatives. Trichilia claussenii, Sorocea bonplandii, Actinostemon concolor, Apuleia leiocarpa and Nectandra megapotamica were the most abundant species and well distributed in the different size classes, and they can be used in the enrichment of areas in process of restoration in the scope of the Deciduous Seasonal Forest in the extreme South of Atlantic Forest Biome. Ocotea puberula, Allophylus edulis, Cedrela fissillis and Machaerium paraguariense formed a group of species with expressive representativeness in the arboreal layer, thus they can be used in the moment of planting as species to the fast covering of the area.