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1

Response of leaf functional traits of Cerasus yedoensis (Mats.) Yü li to serious insect attack

100%
Wang C., Liu J., Xiao H., Du D.
Polish Journal of Environmental Studies
|
2016
|
tom 25
|
nr 1
The morphological features of plants, such as leaf functional traits, are adaptations that enable them to live under different environmental conditions. Thus, leaf functional traits can provide a link between various environmental factors and leaf functions. This study aims to gain insights into the differences in leaf functional traits between healthy (no insect attack) and damaged (serious insect attack) Cerasus yedoensis Yü li. Petiole diameter, leaf length, leaf thickness, ratio of leaf length to petiole length, leaf shape index, and single leaf wet and dry weight of damaged leaves were significantly higher than those of healthy leaves, but lower for leaf moisture and specific leaf area (SLA). Plasticity indices of petiole diameter, petiole length, leaf length, leaf width, and leaf shape index of healthy leaves were higher than those of damaged leaes, but contrary for the plasticity indices of the ratio of leaf length to petiole length, leaf moisture, and SLA of healthy leaves. SLA was positively correlated with leaf moisture but negatively correlated with petiole diameter, leaf length, leaf thickness, ratio of leaf legth to petiole length, leaf shape index, and single leaf wet and dry weight. After serious insect attack, damaged C. yedoensis contained increased quantities of material investment per unit area to exhibit a more efficient anti-herbivore defense; thus, leaf moisture and SLA were decreased, but leaf thickness, and single leaf wet and dry weight were increased. Meanwhile, damaged leaves also were more slender and invested more biomass to the lamina than to the petiole.
2

Anatomical structure of the coracohumeral ligament and its effect on shoulder joint stability

88%
Sun C., Zhong B., Pan Z., Du D., Min X.
Folia Morphologica
|
2017
|
tom 76
|
nr 4
Background: In this study, coracohumeral ligament (CHL) specimens were carefully dissected to observe its length, width, thickness and tension at different positions of the shoulder joint, thereby elucidating its effects on shoulder joint stability. Materials and methods: Fresh frozen shoulder joints from 40 normal adult cadaveric specimens were dissected to reveal the CHL. With the shoulder joints placed at different positions, the length of the CHL and the width and thickness of the middle part of the ligament were measured. The changes in tension of the CHL were also observed. When the shoulder joint maintained the neutral position, the length of the CHL was 52.23 ± 1.02 mm and the width and thickness of the middle part of the ligament were 15.95 ± 0.59 mm and 1.46 ± 0.06 mm, respectively. Results: When the shoulder joint moved from the neutral position to 90° external rotation, from the neutral position to 30° adduction or from the neutral position to 30° flexion/extension or when the shoulder joint is pulled down with a 5 kg weight, the CHL was elongated and thinned, maintaining a strained state. When the shoulder joint moved from the neutral position to 90° internal rotation, from the neutral position to 90° abduction or from the neutral position to 30° flexion/ extension, the CHL was shortened and thickened, maintaining a relaxed state. Conclusions: The CHL may limit the external rotation, adduction and downward movement of the shoulder joint and the process from the neutral position to the 30° flexion/extension, maintaining shoulder joint stability. (Folia Morphol 2017; 76, 4: 720–729)
3

Nitrogen deposition influences the allelopathic effect of an invasive plant on the reproduction of a native plant: Solidago canadensis versus Pterocypsela laciniata

88%
Wang C., Liu J., Xiao H., Zhou J., Du D.
Polish Journal of Ecology
|
2017
|
tom 65
|
nr 1
This study aims to gain insights into the allelopathic effects (by using leaf extracts) of the notorious invasive Solidago canadensis L. on seed germination of the associated Pterocypsela laciniata (Houtt.) C. Shih under different nitrogen (N) forms added: inorganic (NO3--N and NH4 -N), organic (urea-N), and mixed N (a mixture of the three N forms at 1:1:1 ratio). Among the two used concentrations of S. canadensis leaf extracts the higher exhibited inhibitory allelopathic effects on seedling height and biomass, germination potential, germination index, and vigor index of P. laciniata. N demonstrated positive effects on seed germination of P. laciniata. The effects of mixed and organic N on the seedling biomass of P. laciniata were more pronounced than those of inorganic N and control treatment. The vigor index of P. laciniata under mixed N was significantly higher than those under single N form and control treatment. Thus, organic and mixed N showed higher ecological effects on seed germination of P. laciniata than inorganic and single N form. All N forms could alleviate the inhibitory allelopathic effects of S. canadensis on seed germination of P. laciniata. Overall, the inhibitory allelopathic impact of S. canadensis on seed germination of native species may be attenuated under increased and diverse N deposition, thus it could prevent its further invasion.
4

Insights into the effects of simulated nitrogen deposition on leaf functional traits of Rhus typhina

88%
Wang C., Xiao H., Liu J., Zhou J., Du D.
Polish Journal of Environmental Studies
|
2016
|
tom 25
|
nr 3
The effects of anthropogenic nitrogen (N) deposition on successful plant invaders, particularly potential effects on their leaf functional traits, have stimulated considerable research interest. This study aims to gain insights into the leaf functional traits of the controversial invader Rhus typhina in the presence of a gradient of simulated N deposition (control, 0 g L⁻¹; low N, 5 g L⁻¹; medium N, 10 g L⁻¹; and high N, 25 g L⁻¹). Soil pH is decreased under the growth of R. typhina. The soil acidifi cation mediated by R. typhina may be due to the positive effects of R. typhina on soil ammonium concentration and negative effects on soil nitrate concentration. Soil pH decreased under N fertilization due to the release of free H+ via the nitrification process. Leaf width, leaf chlorophyll and N concentrations, SLA, and single leaf wet weight of R. typhina increased in the presence of all N fertilizers; medium N and high N fertilization also increased leaf length and leaf thickness of R. typhina due to the fertilizing effects of the addition of exogenous N on R. typhina growth. Thus, R. typhina leaves may possess higher resource capture ability as well as higher relative growth rate by reducing material investment per unit area under exogenous N fertilization. Meanwhile, medium N fertilization exerts stronger fertilizing effects on leaf length, leaf width, leaf chlorophyll and N concentrations, single leaf wet weight, and leaf thickness of R. typhina than those of high N fertilization. This is possibly because excess N fertilization could drive some unexpected reverse phenomena on leaf growth of R. typhina. Thus, leaf growth of R. typhina may be presumably attenuated with increasing amounts of anthropogenic N deposited into ecosystems in the future, and thereby pose pronounced effects on its subsequent further invasion.
5

Effects of Solidago canadensis invasion and climate warming on soil net N mineralization

64%
Ren G., He M., Li G., Anandkumar A., Dai Z., Zou C. B., Hu Z., Ran Q., Du D.
Polish Journal of Environmental Studies
|
2020
|
tom 29
|
nr 5
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