[Water sources of and in the Tianshan Mountains in summer].

Water use patterns of trees and shrubs in the coniferous forest remain unclear, due to a lack of quantitative analysis on water use dynamics. In this study, the xylem water hydrogen and oxygen stable isotope compositions of and the companion shrub species were measured to detect their water sources. The IsoSource model was used to analyze the relative contribution of each potential water source for both species during summer.

Highly Efficient and Low Cost SPEEK/TiO₂ Nanocomposite Membrane for Vanadium Redox Flow Battery.

In this work, a sulfonated poly(ether ether ketone)/titanium oxide composite membrane (SPEEK/TiO₂) was prepared by solution casting method. The TiO₂ nanoparticles in the polymer matrix not only improved the vanadium ion selectivity of SPEEK/TiO₂, but also enhanced the mechanical stability of this membrane by forming hydrogen bonds with SPEEK. Based on the SPEEK/TiO₂ composite membrane, vanadium redox flow battery (VRB) exhibited ultrahigh coulombic efficiency (over 99.

Effects of Simulated Nitrogen Deposition on Soil Respiration in a Populus euphratica Community in the Ebinur Lake Area, a Desert Ecosystem of Northwestern China.

One of the primary limiting factors for biological activities in desert ecosystems is nitrogen (N). This study therefore examined the effects of N and investigated the responses of an arid ecosystem to global change. We selected the typical desert plant Populus euphratica in a desert ecosystem in the Ebinur Lake area to evaluate the effects of N deposition on desert soil respiration.

[Spatial distribution pattern of Picea schrenkiana var. tianshanica population and its relationships with topographic factors in middle part of Tianshan Mountain].

By the method of point pattern analysis, this paper studied the spatial distribution patterns of different age class individuals in the Picea schrenkiana var. tianshanica forest in middle part of Tianshan Mountain and the influence of topographic factors on the distribution patterns. It was observed that the density of different age class individuals in the forest decreased with the increasing DBH of the individuals, and except old trees which presented a random distribution at the scale of 0-12 m, the saplings and the small, medium, and big trees were in aggregative distribution at all scales.

[Markov process of vegetation cover change in arid area of northwest China based on FVC index].

Based on the fractional vegetation cover (FVC) data of 1982-2000 NOAA/AVHRR (National Oceanic and Atmospheric Administration/ the Advanced Very High Resolution Radiometer) images, the whole arid area of Northwest China was divided into three sub-areas, and then, the vegetation cover in each sub-area was classified by altitude. Furthermore, the Markov process of vegetation cover change was analyzed and tested through calculating the limit probability of any two years and the continuous and interval mean transition matrixes of vegetation cover change with 8 km x 8 km spatial resolution. By this method, the Markov process of vegetation cover change and its indicative significance were approached.