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Detection of SNPs based on DNA specific-locus amplified fragment sequencing in Chinese fir (Cunninghamia lanceolata (Lamb.) Hook)

100%

Su Y. , Hu D. , Zheng H.

Dendrobiology

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2016

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tom 76

EN

Compared to angiosperms, conifers represent more complex genomes with larger giga-genome size. To detect large-scale single nucleotide polymorphisms (SNPs), whole genome sequencing of a conifer population is still unaffordable. In this work, we report the use of DNA specific-locus amplified fragment sequencing (SLAF-seq) for large-scale SNP detection in Chinese fir (Cunninghamia lanceolata (Lamb.) Hook), an ecological and economic important conifer in China. SLAF libraries of 18 parent clones of a Chinese fir 2.5 generation seed orchard were sequenced and a total of 117,924 SLAFs were developed. We detected 147,376 SNPs from these SLAFs; 146,231 of them represented simple nucleotide change in A/G, C/T, A/C, A/T, C/G or G/T. The most frequent SNPs occurred in C/T (34.3%), while the majority of SNPs (68.2%) belonged to transition events (A/G and C/T). Notably, all the sequenced samples had high portion (78.2–80.9%) of common SNPs indicating that the Chinese fir genomes tended to change its nucleotides at common loci. 48,406 informative SNPs were then successfully utilized to genotype the tested samples (n = 18) followed by a phylogenetic tree to clarify their genetic relationship. Furthermore, a set of very high linkage disequilibrium (0.51–1.00) were identified from these informative SNPs. In brief, our work demonstrated that SLAF-seq is an alternative and cost-effectively high-throughput approach for large-scale SNP exploitation in Chinese fir. While the obtained SNPs offer useful marker resource for further genetic and genomic studies and will be helpful for Chinese fir breeding programs.

2

Biomass partition and carbon storage of Cunninghamia lanceolata chronosequence plantations in Dabie Mountains in East China

84%

Xie X. , Cui J. , Shi W. , Liu X. , Tao X. , Wang Q. , Xu X. N.

Dendrobiology

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2016

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tom 76

EN

The quantification of biomass carbon pools is important for understanding carbon cycling in forest ecosystems. This study was designed to reveal the effects of stand age on biomass partitioning and carbon storage of Chinese fir plantation stands in Dabie Mountains of Anhui, East China. A total of six even-aged Chinese fir plantation stands along an age-sequence from 10 to 50 years were selected. To quantify the biomass of different tree components, 18 trees with diameter at breast height (D1.3) from 6.5 to 35.2 cm were harvested from the different aged stands. Biomasses of understory vegetation, forest floor and standing dead trees were also investigated. Total biomass carbon storages ranged from 57.6 to 211.4 Mg ha–1 in the different aged stands. Tree layer comprised from 93.7% to 96.4% of the total biomass C pools in the different aged stands. The C pools of the necromass were from 1.8 to 6.2 Mg ha–1. Stand age had a significant effect on tree biomass partitioning, with an increase in proportion of root biomass. The root/shoot ratios were from 0.187 to 0.312, which was significantly positively correlated to stand age. The existing plantation stands are still developing and have somewhat high rate of biomass and carbon accumulations beyond the normal rotation period (usually 25–30 years) even over an age of 50 years. Appropriate prolongation of the rotation period of Chinese fir plantation will be effective in maintaining long-term productivity and providing large carbon sink. The measurements provide valuable data for modelling productivity of Chinese fir plantation forest.

3

Quantification of individual tree competition index taking Chinese-fir plantations in subtropical low hilly area as an example

84%

Zhang Y. , Deng X. , Huang Y. , Li Y. , Xiang W. , Yan W.

Polish Journal of Ecology

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2019

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tom 67

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nr 1

EN

Competition among trees is a fundamental interaction process within plant community, which is the theoretical basis of thinning. Plant competitive intensity is generally measured using a competition index (CI) that can be classified into two major categories: distance-independent and distance-dependent. The current study used Cunninghamia lanceolata (Lamb.) Hook as the test subject and used Hegyi's CI (distance-dependent), to quantify individual CI and their relationship with tree diameter at breast height (DBH). Five different criteria were used to select potential competitors for the calculation of CI. Seven basic linear and nonlinear mathematical functions were used to test and quantify the relationships between DBH of the target tree and the individual CI. Results showed that individual CI was negatively correlated with target tree DBH: as DBH increased, competition intensity weakened. The adjusted R² with five different criteria of selection competitors simulated by seven functions ranged from 0.30 to 0.82. Considering the root mean square error (RMSE), P-value, and adjusted-R², our results suggested that the best model to simulate the relationship between individual CI and focal tree DBH was power function (CI = 43.98 × DBH⁻¹‧⁰⁸, adjusted R² = 0.81) and with the Voronoi diagram method as the criteria for selecting competitors. These results can demonstrate a clearer understanding of the spatial structure of forests, and can be used to guide the selection of thinning trees in the process of thinning practice.

4

Elevation distribution of fine root biomass and soil organic carbon storage of mature Chinese fir (Cunninghamia lanceolata) plantations in East China

84%

Wang Q. , Teng Z. , Wang J. , Xie X. , Xu X.

Polish Journal of Ecology

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2020

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tom 68

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nr 1

5

Elevation Distribution of Fine Root Biomass and Soil Organic Carbon Storage of Mature Chinese Fir (Cunninghamia lanceolata) Plantations in East China

67%

Wang Q. , Teng Z. , Wang J. , Xie X. , Xu X.

Polish Journal of Ecology

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2020

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tom Vol. 68, nr 1

84--93

EN

Fine roots play an important role in productivity and dynamics of carbon and nutrient in forest ecosystems. The objective of this study is to reveal the elevational distribution patterns of fine-root (≤ 2 mm in diameter) biomass and its carbon and nitrogen stoichiometry, and the relationship between fine-root biomass and soil organic carbon storage in mature Chinese fir (Cunninghamia lanceolata) plantations (40-45 year old) in Mt. Dabie, eastern China. A field survey was conducted at five different sites along an elevation gradient from 360 m to 1200 m a.s.l. At each site, the sampling stands had similar density (from 1039 to 1238 stems ha–1) with three replicates. The fine-root biomass was ranged from 264.3 to 331.9 g m–2, with marginal significant correlation to elevation (P = 0.052). However, fine-root necromass was significantly decreased with elevation (P = 0.010). The C:N ratios ranged from 52.9 to 56.4 for living fine-roots and from 47.3 to 51.2 for dead ones, and showed an increasing trend over elevation gradient. Soil organic carbon (SOC) storages in the surface 50-cm soil layer ranged from 59.7 to 97.9 Mg ha–1 and significantly increased with elevation (P < 0.001). Positive correlations were observed between fine-root biomass and SOC density across this elevation gradient. These results indicate that fine-root turnover might be an important regulation of SOC in the Chinese fir plantation.