Subjects: Library Science，Information Science >> Information Science submitted time 2023-04-01 Cooperative journals: 《图书情报工作》
Abstract： [Purpose/significance] Since the 21st century, the proportion of databases in the procurement resources of university libraries has been increasing, and foreign language databases have been an important source of electronic resources. At the same time, facing the strict requirements of various supervision and auditing work, the staff also encountered many problems in the process of purchasing and constructing foreign language database resources. Taking Fudan University Library as an example, through the analysis and research on the resource ordering and usage condition of the four foreign language databases of Elsevier SD, Wiley, Springer and Taylor-ST ordered by Fudan University Library, it provides ideas and references for the decision-making of foreign language database construction in university libraries.[Method/process] Based on the statistical data of the four foreign language databases, this paper classified and summarized the overview of the collection resources, the guarantee overview of the double-class discipline construction, the annual utilization status and the annual high-cited non-collection journals. From these four analysis perspectives, the data was coded based on the grounded theory, and then combined with specific data to obtain a comprehensive usage table of foreign language databases, and the gray relational analysis method was used to calculate and evaluate the influence of each indicator.[Result/conclusion] Through calculations, this paper identifies the five most critical annual downloads, citations, publications, total number of periodicals in the collection, and the proportion of core periodicals that affect the use of the foreign language databases in Fudan University Library. From three perspectives of bibliometrics of academic achievements, literature measurement and resource guarantee, this paper provides optimization suggestions for the construction of foreign language databases in Chinese university libraries, and provides methodological reference and key targets, basis and ideas for subsequent research on the construction of information resources in other universities.
Subjects: Biology >> Botany >> Plant ecology, plant geography submitted time 2016-05-03
Abstract： Aims Sparse Ulmus pumila forest is an intrazonal vegetation in Onqin Daga Sandy Land, Populus simonii has been widely planted for windbreak and sand dune stabilization. Our objective was to compare the differences in carbon (C) density of these two forests and their relationships with stand age. Methods We measured the C content of tree organs (leaf, twig, stem, and root), herb layers(above ground vegetation and below ground root) and soil layers (up to 100 cm) in sparse Ulmus pumila forests and Populus simonii plantations of different stand ages, and then computed C density and their proportions in total ecosystem carbon density. In addition, we illustrated the variation of tree layer, soil layer and total ecosystem carbon density with stand age, and then estimated the C sequestration rates for these two ecosystems by the space-for-time substitution approach. Important findings The average C contents of tree layer and soil layer for sparse Ulmus pumila forests were lower than those for Populus simonii plantations. The total C density of sparse Ulmus pumila forests was half of that of Populus simonii plantations. The carbon density of soil and tree layers accounted for more than 98% of ecosystem C density in both two forests. Irrespective of forest type, the C density ratios of soil to vegetation decreased with stand age. This ratio was 1.66 for sparse Ulmus pumila forests and 1.87 for Populus simonii plantations, respectively when they were over-matured. The C density of tree layer, soil layer, and total ecosystem in both forests increased along forest development. There were significant linear positive correlations between tree layer’s C density and stand age in both forests and between the total ecosystem C density of Sparse Ulmus pumila forests and stand age. The C sequestration rate of tree layer was 5-fold higher in Populus simonii plantation than in sparse Ulmus pumila forest. The C sequestration rate of ecosystem was 0.81 Mg C hm–2 a–1 for sparse Ulmus pumila forest and 5.35 Mg C hm–2 a–1 for Populus simonii plantation. These findings have implications for C stock estimation of sandy land forest ecosystems and policy-making of ecological restoration and C sink enhancement in the studied area.
Peer Review Status:
Awaiting Review
Subjects: Biology >> Botany >> Applied botany submitted time 2023-12-24 Cooperative journals: 《广西植物》
LUO Yahuang
MA Liangliang
GAO Lianming
WANG Xinjie
ZHAO Wei
YANG Xingliang
MA Shaobin
SHI Xiaochun
LIU Jie
Abstract： A better understanding of the spatiotemporal dynamics of species composition and biodiversity provides significant insights into the distribution patterns of biodiversity and the prediction of biodiversity fate in a global change context. However, how species and phylogenetic diversity change along elevational gradient with temporal scale in mountain ecosystems is largely unknown. In this study, we used census data (2004, 2008 and 2013) of an elevational transect (elevational range 960-2 878 m) covering eastern and western slopes of Gaoligong Mountains, SW China, to investigate the spatiotemporal dynamics of forest arbor layer (DBH≥5 cm) species diversity and phylogenetic diversity. The results were as follows: (1) Species diversity was humpshaped along the elevational gradient, while the phylogenetic diversity increased with increasing elevation. Clustering phylogenetic structure was observed at low elevations, and overdispersed or random structure was detected at high elevations. (2) Overall, temporal species and phylogenetic beta diversity analysis showed no significant difference among these three investigation time points. However, we found a higher clustering of phylogenetic structure along the temporal scale. (3) Spatial beta diversity showed that there was a significant loss of species at low elevations (960-1 381 m) on the eastern slope, where the vegetation has been disturbed or completely converted into farmland. The main lost species including Terminalia chebula, Quercus acutissima,Pistacia weinmanniifolia, Hovenia acerba and Ilex wattii. In contrast, the change in the western slope is mild at low elevations, only observing species abundance increasing, which include Cyclobalanopsis oxyodon, Symplocos chinensis, and Taiwania cryptomerioides. Therefore, we speculate that the change in species and phylogenetic diversity of the arbor layer of subtropical evergreen broadleaf forest may be related to succession process and climatic change in middle and high elevations, while the communities at low elevations were seriously impacted by human activities in the Gaoligong Mountains. The results will deepen the understanding of the mechanisms of plant community dynamics in the Gaoligong Mountains and provide new insights to guide precise conservation strategies in the region.
Subjects: Biology >> Botany >> Plant ecology, plant geography submitted time 2016-05-03
Abstract： Aims Forest carbon storage in Inner Mongolia plays a significant role in national terrestrial carbon budget due to its largest forest area in China. Our objectives were to estimate the carbon storage in the forest ecosystems in Inner Mongolia, and to reveal its spatial pattern. Methods In the study, field survey and sampling were conducted at 137 sites, which were nearly evenly distributed in most forest types in the study region. At each site, the ecosystem carbon density at each site was estimated thorough sampling and measuring pools of soil (0–100 cm) and vegetation, including biomass of tree, grass, shrub, and litter. Regional carbon storage was further calculated with the estimated carbon density for each forest type. Important findings Carbon storage of vegetation layer in forests in Inner Mongolia was 787.8 Tg C, with the biomass of tree, litter, herbaceous and shrub account for 93.5%, 3.0%, 2.7% and 0.8%, respectively. Carbon density of vegetation layer was 40.4 t?hm–2, with 35.6 t?hm–2 in trees, 2.9 t?hm–2 in litter, 1.2 t?hm–2 in herbaceous and 0.6 t?hm–2 in shrubs. In comparison, carbon storage of soil layer in forests in Inner Mongolia was 2449.6 Tg C, with 79.8% distributed in the first 30 cm. Carbon density of soil layer was 144.4 t?hm–2. Carbon storage of forest ecosystem in Inner Mongolia was 3237.4 Tg C, with vegetation and soil accounting for 24.3% and 75.7%, respectively. Carbon density of forest ecosystem in Inner Mongolia was 184.5 t?hm–2. Carbon density of soil layer was positively correlated with that of vegetation layer. Spatially, both carbon storage and carbon density were higher in the eastern area, where the climate is more humid. Forest reserve construction and artificial afforestation can significantly improve the capacity of regional carbon sink.
Peer Review Status:Awaiting Review
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