scholarly journals Some Characteristics of Bacteria Isolated from the Ectomycorrhiza of Chinese Pine Inoculated with Cenococcum graniforme.

1998 ◽  
Vol 13 (1) ◽  
pp. 17-21
Author(s):  
WU BINGYUN ◽  
ICHIO NIOH
Forests ◽  
2019 ◽  
Vol 10 (9) ◽  
pp. 752
Author(s):  
Liu ◽  
Bao ◽  
Bao

Chinese pine (Pinus tabulaeformis Carr.) plays an important role in maintaining ecosystem health and stability in western Liaoning Province and the southern Horqin sand land, Northeast China, with benefits including sand fixation and soil erosion. In the context of climate change, developing a better understanding of the relationship between climate factors and growth rates of this species will be extremely valuable in guiding management activities and meeting regional conservation objectives. Here, the results based on two groups of tree-ring samples show that the radial growth of Chinese pine is controlled primarily by water conditions. The longer chronology had the highest correlation coefficient with the January–September mean self-calibrating Palmer Drought Severity Index (scPDSI); therefore, drought variability was reconstructed for the period 1859–2014. Statistical analysis showed that our model explained 41.9% of the variance in radial growth during the 1951–2014 calibration period. Extreme dry and wet events, defined as the criteria of one standard deviation less or greater than the mean value, accounted for 19.9% and 18.6% of the 156-year climate record, respectively. During the past century, the regional hydroclimate experienced significant long-term fluctuations. The dry periods occurred from the early-1900s–1930s and 1980s–2000s, and the wet periods occurred from the 1940s–1970s. The drought reconstruction was consistent with the decreasing trend of the East Asian summer monsoon since the late 1970s. The reconstructed temporal patterns in hydroclimate in western Liaoning were closely related to the large-scale climate drivers in the North Pacific and the tropical equatorial Pacific. The teleconnections were confirmed by spatial correlations between the reconstructed sequence and sea surface temperature (SST) in the North Pacific, as well as the correlations with the Pacific Decadal Oscillation (PDO) and El Niño Southern Oscillation (ENSO) indices. Aerosols played an important role in affecting drought variations over the past several decades. Moisture stress caused by global warming and interdecadal changes in the PDO will have long-term effects on the growth of pines in the study area in the future.


Nematology ◽  
2020 ◽  
Vol 22 (8) ◽  
pp. 843-853
Author(s):  
Jianfeng Gu ◽  
Munawar Maria ◽  
Yiwu Fang ◽  
Xianfeng Chen ◽  
Lele Liu

Summary Laimaphelenchus spiflatus n. sp. isolated from declining Chinese pine, Pinus tabuliformis, is described and illustrated. The new species can be characterised by its relatively long body size of 1150 ± 108 (976-1437) μm for females and 1092 ± 78.6 (905-1235) μm for males, lateral field with four lines, females with a long vulval flap, and tail conoid, slightly ventrally curved and ending in a stalk having 8-12 projections when observed with SEM. Males are common, with 27.3 (23.4-28.8) μm long spicules having blunt (not well-developed) condylus and rostrum and truncate simple distal tip, and four caudal papillae. By having a vulval flap, four lateral lines and tail end with a stalk (without four tubercles), the new species comes close to L. preissii, L. simlaensis, and L. unituberculus, but can be differentiated from them by morphological characters and morphometric data. In phylogenetic analyses using near full length 18S and D2-D3 expansion segments of 28S rDNA, Laimaphelenchus spiflatus n. sp. appeared as an independent lineage separated from the other Laimaphelenchus spp. that are currently sequenced for their aforementioned genomic regions.


PROTOPLASMA ◽  
2005 ◽  
Vol 225 (1-2) ◽  
pp. 5-14 ◽  
Author(s):  
Fengli Guo ◽  
Shi-Yi Hu ◽  
Zongfei Yuan ◽  
Sze-Yong Zee ◽  
Yuzhen Han

Forests ◽  
2018 ◽  
Vol 9 (11) ◽  
pp. 680 ◽  
Author(s):  
Xuan Yu ◽  
Lin Yang ◽  
Shixuan Fei ◽  
Zitong Ma ◽  
Ruqian Hao ◽  
...  

Gaps by thinning can have different microclimatic environments compared to surrounding areas, depending on the size of the gap. In addition, gaps can play important roles in biological dynamics, nutrient cycling, and seedling regeneration. The impacts of gap size on soil microbial communities and enzyme activities in different soil layers in Chinese pine plantations are not well understood. Here, we created gaps of 45 m2 (small, G1), 100 m2 (medium, G2), and 190 m2 (large, G3) by thinning unhealthy trees in an aged (i.e., 50 years old) monoculture Chinese pine plantation in 2010. Soil samples were collected in 2015. The total, bacterial, Gram-positive (G+), and Gram-negative (G−) phospholipid fatty acid (PLFA) profiles were highest in medium gaps in both the organic and mineral layers. These indicesdecreased sharply as gap size increased to 190 m2, and each of the detected enzyme activities demonstrated the same trend. Under all the gap size managements, abundances of microbial PLFAs and enzyme activities in the organic layers were higher than in the mineral layers. The soil layer was found to have a stronger influence on soil microbial communities than gap size. Redundancy analysis (RDA) based on the three systems with different gap sizes showed that undergrowth coverage, diversity, soil total nitrogen (TN), total organic carbon (TOC), and available phosphorus (AT) significantly affected soil microbial communities. Our findings highlighted that the effect of gap size on soil microenvironment is valuable information for assessing soil fertility. Medium gaps (i.e., 100 m2) have higher microbial PLFAs, enzyme activity, and soil nutrient availability. These medium gaps are considered favorable for soil microbial communities and fertility studied in a Chinese pine plantation managed on the Loess Plateau.


Forests ◽  
2019 ◽  
Vol 10 (9) ◽  
pp. 781 ◽  
Author(s):  
Boheng Wang ◽  
Yuankun Bu ◽  
Yanjie Li ◽  
Weizhong Li ◽  
Pengxiang Zhao ◽  
...  

Shrub layer diversity is an essential component of the forest ecosystem diversity, that contributes significantly to structuring the community and maintaining diversity, especially in plantation forests. In previous studies, researchers have reported the strong relationship among various factors (i.e., soil composition, mean annual temperature, etc.) and shrub diversity. However, how these factors jointly influence shrub diversity and which factors could be considered the key factors is still unknown. In this study, we attempted to quantify the effect among environmental factors, soil factors and forest stand factors on shrub diversity. Twenty-seven variables were selected from 57 Chinese pine plantation plots in Huanglong Mountain, Yanan City, Shaanxi Province, China. The path models showed that latent variable of soil properties is the main effective factor of latent variable of shrub diversity (directly effect, path coefficient = 0.344) and the latent variable of site conditions is another effective factor of latent variable of shrub diversity (indirectly effect, path coefficient = 0.177); Besides, the latent variable of site conditions and forest properties directly affect the latent variable of soil properties (path coefficient = 0.514 and 0.326, respectively). Among the latent variable of soil properties, soil water content (SWC) has the biggest weight of 0.666, which indicated the most significant contribution of SWC to latent variables of shrub diversity. Total nitrogen, weighted 0.375, and total phosphorus, weighted 0.308, are also important factors and make a similar contribution to latent variable of shrub diversity. Soil organic matter (SOM) has a minimal impact (lowest weight, 0.059); among the objective variables of site condition, altitude contributes the most and is followed by litter thickness, weighted at 0.722 and 0.448, respectively. Furthermore, among all the variables affecting the latent variable of forest properties, forest age is recognized as the maximum impactor of soil property change, which weighted −0.941; and is followed by forest stock volume and diameter at breast height (DBH), weighted 0.795 and 0.788, respectively. The crowding index (C) has the lowest weight (−0.235) and demonstrated that spatial distribution and crowding of trees have minimal impact on the latent variable of Soil properties. diversity Overall, our study provides new insights into quantifying the relationships among different driving factors that potentially play a significant role in determining shrub layer diversity within the plantation forest.


Mycologia ◽  
1970 ◽  
Vol 62 (3) ◽  
pp. 585-585 ◽  
Author(s):  
V. Mejstřík

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