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1

Numerical analysis of consolidation settlement and creep deformation of artifical island revetment structure in a large-scale marine reclamation land project

100%
Zhao J., Zhou T., Wang G.-X.
Polish Maritime Research
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2015
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tom 22
|
nr Special Issue S1
In order to analyze the influential factors of soft foundation settlement in a marine reclamation land project, the consolidation settlement and pore pressure dissipation of the entire area are numerically simulated using Soft-SoilCreep Model, in which the PLAXIS finite element software for professional geotechnical engineering is applied and empirical data of Japanese Kansai’s airport project are used. Moreover, the figures of settlement and pore pressure results in the different basic period are drawn, and the corresponding analysis conclusions are ob-tained based on the comparison among the results from the computational parameters of depth. In addition,, the influence rules of various parameters on settlement results is concluded through running the parameter sensitivity analysis in Soft-Soil-Creep Model, and the experience and conclusions can be for reference in the design and con-struction of similar large-scale marine reclamation land project. Also the empirical value method of the creep index has not been applied widely. Further research needs to be done
2

Age-related relationship between annual productivity and body size of trees: testing the metabolic theory

100%
Cheng D. L., Wang G.-X., Zhong Q.-L.
Polish Journal of Ecology
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2009
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tom 57
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nr 3
441-449
Metabolic theory of ecology predicts a 3/4 power relationship between annual productivity PT and body size MT (i.e., P ∞ M3/4), which has important implications to estimates of carbon fluxes, ecosystem health, global carbon budgets, and a variety of other phenomena. To test this prediction, we examined a large dataset for Chinese forests. Such dataset covers six major forest biomes and a total of 17 forest types grown across a range of annual temperature (–6.6 to 25.2ºC), mean annual rainfall (27 to 2989 mm), elevation (10 to 4240 m a.s.l.), and stand age (3 to 350 yrs.). Reduced major axis (RMA) regression analyses were used to compare the PT versus MT scaling exponents and normalization constants (i.e., slopes and Y-intercepts of log-log linear relationships, respectively). Comparisons were made for ten different age-sequences (stand age ranges from 20 to 200 yrs). When stand age was less than 100 yrs, relationship of PT versus MT had similar scaling exponents (αRMA » 1.0), while the Y-intercepts decreased systematically. When stand age exceeded 140 yrs, scaling exponents decreased (αRMA <0.86). Both the aboveground annual productivity and aboveground body size per individual tree (PA and MA, respectively) showed the same behavior. We therefore conclude that the relationship of PT versus MT systematically declined with the stand age, and was inconsistent with the predictions of metabolic theory
3

Invariant allometric relationship between above- and below-ground biomass along a moisture gradient in North - West China

88%
Cheng D. L., Wang G.-X., Tang Q.-L., Li T., Zhong Q.-L.
Polish Journal of Ecology
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2009
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tom 57
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nr 4
669-675
Biomass allocation pattern is an important plant characteristic which influences how plants respond to abiotic and biotic heterogeneity. Prior studies indicate that above-ground biomass scales nearly isometrically with respect to below-ground biomass regardless of environment or phyletic affinity. However, such rule has been mostly tested with data on trees and usually without drought stress. Given the importance of this predicted relationship, it should be evaluated for a wider range of species and environmental conditions. Variations of the above- and belowground biomass (MA and MR, respectively) were determined from five sites in north-west China, which compose a natural moisture gradient (aridity index ranging from 0.95 to 1.98). Model Type II regression protocols were used to compare the numerical values of MA vs MR scaling exponents (i.e. slopes of log-log linear relationships). The resulting five scaling exponents were indistinguishable and had a similar, nearly isometric slope (i.e. MA ∞ MR ͌ ¹‧⁰). Significant variation was observed in the Y-intercepts of the five regression curves, because of the absolute differences in MA or MR. These results support prior allometric theory, which reveals an isometric relationship between above- and below-ground biomass, and may provide a suitable method to estimate the regional below-ground biomass based on the direct aboveground measurements.
4

Isometric scaling relationship between leaf number and size within current-year shoots of woody species across contrasting habitats

88%
Li T., Deng J.-M., Wang G.-X., Cheng D.-L., YU Z.-L.
Polish Journal of Ecology
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2009
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tom 57
|
nr 4
659-667
The scaling relationship between the number and size of plant’s components has been observed traditionally as reflective of a trade-off in resource allocation over ontogeny. The recent finding of a negative isometric leaf size/number trade-off across 24 deciduous woody species extends knowledge of such trade-offs to current-year shoots. Before generally accepted, this isometry has to be consistent across more datasets that represent diverse habitats. We tested this scaling relationship using 12 deciduous shrub species from the western Gobi Desert and 56 woody species from the northeastern temperate zone of China. Our results showed that leaf number per stem mass of current-year shoots scaled approximately isometrically with individual leaf mass within and across habitats, which, combined with the independence of total leaf mass and individual leaf mass, supports isometric scaling for shoot-scale leaf deployment. However, the intercepts of these relationships decreased significantly along the environmental gradients, suggesting that habitats could place a constraint on the total leaf number that can be supported by a given size shoot. Convergence towards higher leaf number and smaller leaf size for some desert species suggests important adaptive implications for photosynthetic carbon gain and reproductive growth.
5

Plants interactions between Suaeda salsa individuals are mediated by salinity stress

76%
Zhang H., Li J.-N., Wang G.-X., Dai X.-F., Qiu M.-Q., Zheng K.-F.
Acta Physiologiae Plantarum
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2008
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tom 30
|
nr 1
To test how plants interactions change with environmental stress, neighbors removal experiments in Suaeda salsa communities of beach were conducted in Hangzhou bay Zhejiang Province, China. Results showed that there is a significant shift from positive interaction in high salinity stress to negative interaction in low salinity stress. Removal experiments also clarified the role of phenotype response in linking plants interactions and environmental stress. Under low salinity stress, biomass, stem length, root length, leaf area, and photosynthesis rate, water-use efficiency of neighbors removal plants were higher than those of control plants, while leaf water content of neighbors removal plants were lower than those of control plants. Under high salinity stress, biomass, stem length, root length, leaf area, and photosynthesis rate, leaf water content of neighbors removal plants were lower than those of control plants, while water-use efficiency of neighbors removal plants were higher than those of control plants. It can be concluded that S. salsa interactions were mediated by salinity stress through morphological and physiological plasticity.
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