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Nutrient Uptake and Allocation by Plants in Recent Mounds Created by Subterranean Rodent, Plateau Zokor Eospalax baileyi

Wu R., Wei X., Liu K., Zhong M., Liu Y., Pan D., Shao X.

Polish Journal of Ecology

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2017

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Vol. 65, nr 1

132--143

EN

To understand the nutrient absorption and adaptability of plant species that initially colonize mounds and the influences of the plateau zokor on the diversity of the plant community after 4 years' period, a series of experiments was conducted in an alpine meadow on the Qinghai-Tibetan Plateau. The contents of C and N and the flow of N in pioneer species were measured and tracked using the 15N isotope tracer method, and the species diversity on 4-year-old mounds was investigated. The results showed that (1) plateau zokors could influence the plant species on the mounds by creating gaps in the grassland; (2) Elymus nutans and Elsholtzia feddei, with high rates and efficiencies of nutrient absorption and transportation, were more competitive on the newly formed mounds than other species; (3) Elymus nutans played a dominant role in the plant community of the mounds; and (4) plateau zokors did not change the plant diversity after 4 years' period. These findings indicated that species colonizing the mounds experienced a process of competition when gaps were created by the rodents, that species with greater capabilities for resource acquisition and utilization had stronger competitiveness and vice versa, and that after a few years, the plant diversity on the mounds was almost similar to that of the undisturbed grassland.

2

Leaf morphology shift of three dominant species along altitudinal gradient in an alpine meadow of the Quinghai â Tibetan Plateau

Zhong M., Wang J., Liu K., Wu R., Liu Y., Wei X., Pan D., Shao X.

Polish Journal of Ecology

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2014

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Vol. 62, nr 4

639--648

EN

It has been observed that leaf morphology shift within species is linked to climate change, but there are few studies on the effects of altitude change on leaf morphology of species. We hypothesized that similar to climate change, a morphological shift within species would occur over time under different growing altitudes. In this study, we evaluated three dominant grass species: Elymus nutans Griseb., Kobresia capillifolia Clarke., Carex moorcroftii Boott., taking advantage of the altitudinal variations (3000-4000 a.s.l.) on the Qinghai-Tibetan Plateau. Our study showed that almost all leaf traits of these three species had significant differences (P <0.05) across an altitudinal gradient. Different species responded differently to altitude change. Leaf thickness (LT) of the three species increased with increase in altitude. Leaf area (LA) of E. nutans and C. moorcroftii decreased with increasing altitude, but that of K. capillifolia increased. There was no obvious linear effect on leaf dry matter content (LDMC) and specific leaf area (SLA) of these three species. LDMC of E. nutans and C. moorcroftii showed a trend of increase, while that of K. capillifolia decreased. SLA of E. nutans and K. capillifolia showed a trend of increase, but that of C. moorcroftii decreased with increase in altitude. In addition, soil pH (pH) and air temperature (AT) decreased with increase in altitude. However, other soil and climate factors increased as altitude increased. The finding of this work is that leaf morphology shift within species happens under altitude change to adapt to specific environment.

3

A new composite, Co-Sn metal oxide anode for lithium ion batteries

Huang F., Lu X. Z., Zhang Y. F., Luo X. Y., Yu C., Wu R.

Materials Science Poland

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2009

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Vol. 27, No. 1

239--248

EN

The structural and morphological evolution of cobalt-tin (Co-Sn) metal composite oxides, synthesized by the decomposition of CoSn(OH)6 precursor at various temperatures, were investigated by X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM). The precursor was also studied by thermal analysis (TG/DTA). The electrochemical performance of nanosized Co-Sn composite metal oxides was investigated to evaluate their suitability for use as anode materials for Li ion batteries. The results revealed that the samples heat-treated at low temperatures consisted of amorphous CoSnO3, and the samples heat-treated at high temperatures comprised crystalline Co2SnO4 and SnO2. The charge capacity and cyclability were sensitive to the structure and composition of the electrode active materials. The samples heat-treated in the phase transition temperature range exhibited relatively worse electrochemical properties.

4

Ewolucja optyczna systemów transportowych

Bonenfant P., Manchester J., Varma E., Wu R.

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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1998

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nr 4

265-271

PL

Omówiono perspektywy rozwoju warstwy optycznej sieci transportowych. Przedstawiono powstające elementy sieci optycznych; ich zastosowanie i podstawowe cechy funkcjonalne. Podano stan prac standaryzacyjnych dotyczących sieci optycznych.

EN

The article describes the perspectives of optical layer development in the transport networks. The employment and basic functional feaures of the developing optical network elements have been presented. Standarisation status of optical networks has been provided.